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Huang DD, Hu Q, He X, Huang RJ, Ding X, Ma Y, Feng X, Jing S, Li Y, Lu J, Gao Y, Chang Y, Shi X, Qian C, Yan C, Lou S, Wang H, Huang C. Obscured Contribution of Oxygenated Intermediate-Volatility Organic Compounds to Secondary Organic Aerosol Formation from Gasoline Vehicle Emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 38829825 DOI: 10.1021/acs.est.3c08536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
Secondary organic aerosol (SOA) formation from gasoline vehicles spanning a wide range of emission types was investigated using an oxidation flow reactor (OFR) by conducting chassis dynamometer tests. Aided by advanced mass spectrometric techniques, SOA precursors, including volatile organic compounds (VOCs) and intermediate/semivolatile organic compounds (I/SVOCs), were comprehensively characterized. The reconstructed SOA produced from the speciated VOCs and I/SVOCs can explain 69% of the SOA measured downstream of an OFR upon 0.5-3 days' OH exposure. While VOCs can only explain 10% of total SOA production, the contribution from I/SVOCs is 59%, with oxygenated I/SVOCs (O-I/SVOCs) taking up 20% of that contribution. O-I/SVOCs (e.g., benzylic or aliphatic aldehydes and ketones), as an obscured source, account for 16% of total nonmethane organic gas (NMOG) emission. More importantly, with the improvement in emission standards, the NMOG is effectively mitigated by 35% from China 4 to China 6, which is predominantly attributed to the decrease of VOCs. Real-time measurements of different NMOG components as well as SOA production further reveal that the current emission control measures, such as advances in engine and three-way catalytic converter (TWC) techniques, are effective in reducing the "light" SOA precursors (i.e., single-ring aromatics) but not for the I/SVOC emissions. Our results also highlight greater effects of O-I/SVOCs to SOA formation than previously observed and the urgent need for further investigation into their origins, i.e., incomplete combustion, lubricating oil, etc., which requires improvements in real-time molecular-level characterization of I/SVOC molecules and in turn will benefit the future design of control measures.
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Affiliation(s)
- Dan Dan Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Qingyao Hu
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Xiao He
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518000, China
| | - Ru-Jin Huang
- State Key Laboratory of Loess and Quaternary Geology, Center for Excellence in Quaternary Science and Global Change, Institute of Earth and Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Xiang Ding
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yingge Ma
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Xinwei Feng
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Sheng'ao Jing
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yingjie Li
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Jun Lu
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yaqin Gao
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Yunhua Chang
- KLME & CIC-FEMD, Yale-NUIST Center on Atmospheric Environment, Nanjing University of Information Science & Technology, Nanjing 210044, China
| | - Xu Shi
- Shanghai Motor Vehicle Inspection Certification & Tech Innovation Center Co., Ltd., Shanghai 201805, China
| | - Chunlei Qian
- Shanghai Motor Vehicle Inspection Certification & Tech Innovation Center Co., Ltd., Shanghai 201805, China
| | - Chao Yan
- Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki 00014, Finland
- Joint International Research Laboratory of Atmospheric and Earth System Research, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
| | - Shengrong Lou
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Hongli Wang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Cheng Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
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Zhang X, He X, Cao Y, Chen T, Zheng X, Zhang S, Wu Y. Comprehensive characterization of speciated volatile organic compounds (VOCs), gas-phase and particle-phase intermediate- and semi-volatile volatility organic compounds (I/S-VOCs) from Chinese diesel trucks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168950. [PMID: 38043810 DOI: 10.1016/j.scitotenv.2023.168950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/13/2023] [Accepted: 11/25/2023] [Indexed: 12/05/2023]
Abstract
We established the comprehensive emission profiles of organic compounds for typical Chinese diesel trucks. The profiles cover the entire volatility range, including speciated volatile organic compounds (VOCs), intermediate-volatility organic compounds (IVOCs), and semi-volatile organic compounds (SVOCs). The VOCs and I/SVOCs were analyzed by one-dimensional gas chromatography quadrupole mass spectrometry (GC qMS) and two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-ToF-MS) separately. The impacts of starting mode and aftertreatment technology on the VOC, gaseous and particulate I/SVOC emissions, and the gas-particle partitioning were investigated. The emission factor (EF) of gas phase I/SVOCs was approximately 10 times higher than that of particle phase I/SVOCs and the chemical compositions and volatility distributions varied greatly. VOC, IVOC, and SVOC emissions significantly decreased when vehicles were equipped with advanced aftertreatment technologies. Diesel particulate filters (DPF) can remove >71 % VOC, 74 % gaseous, and 88 % particulate I/SVOCs, many of which are significant secondary organic aerosol (SOA) precursors. The chemical compositions and volatility distributions of the gaseous I/SVOCs and unburned diesel fuel were similar, revealing that diesel fuel is the main origin of the gaseous I/SVOCs. The I/SVOC emission profiles covering the whole volatility range, i.e., log10C* = -3 to 10 (C*: effective saturation concentration, μg m-3) were established.
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Affiliation(s)
- Xiao Zhang
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China
| | - Xiao He
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yihuan Cao
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China
| | - Ting Chen
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Xuan Zheng
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Shaojun Zhang
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China; Beijing Laboratory of Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, China.
| | - Ye Wu
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China; Beijing Laboratory of Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, China
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3
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Cui M, Xu Y, Liu Z, Zhang Y, Zhang F, Yan C, Chen Y. Characteristics of intermediate volatility organic compounds emitted from inland vessels with different influential factors and implication of reduction emissions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166868. [PMID: 37678527 DOI: 10.1016/j.scitotenv.2023.166868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 08/23/2023] [Accepted: 09/04/2023] [Indexed: 09/09/2023]
Abstract
Ships could emit an abundance intermediate volatility organic compounds (IVOCs). In recent years, many studies on the emission characteristics of IVOCs have focused on the burning of heavy fuel oil by ocean-going ships; however, few have focused on inland vessels which have a more significant impact on air quality and human health owing to their closer proximity to cities than ocean-going ships. In this study, the IVOC emission factors (EFIVOCs) of three inland vessels were determined using a dilution sampling system considering different influencing factors (ship age and operating conditions). The results showed that the EFIVOCs values ranged from 869.9 to 7607 mg/kg fuel, with an average of 4128 ± 2703 mg/kg fuel. In addition, the age of the vessel was found to have a dramatic effect on emissions with the average EFIVOCs of inland vessels aged >10 years was 4300 ± 4319, 5769, and 6484 ± 1586 mg/kg fuel under cruising, idling, and maneuvering conditions, respectively, while that of vessels <10 years old was 1180 ± 328.3 mg/kg fuel when maneuvering. The percentages of emission factors for unresolved complex mixture (UCM), normal alkanes (n-alkanes), branched alkanes (b-alkanes), and polycyclic aromatic hydrocarbons (PAHs) from inland vessels were 82.1 ± 2.6 %, 5.2 ± 0.9 %, 10.6 ± 2.0 % and 2.0 ± 0.6 % of the total IVOCs, respectively. The secondary organic aerosols (SOA) production of inland vessels was estimated to be 1212 ± 801.7 mg/kg fuel, which was substantially higher than those of diesel vehicles, non-road construction machinery, and gasoline vehicles reported by other researches. Moreover, based on the ship movement and measured EFIVOCs data, the IVOCs emission inventory of inland vessels in Jiangsu Province and China in 2016 was 4.2 ± 2.8 and 32.0 ± 21.0 Gg respectively, which was comparable to those from diesel vehicle emissions.
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Affiliation(s)
- Min Cui
- College of Environmental Science and Engineering, Yangzhou University, Yangzhou 225009, PR China.
| | - Yuanyuan Xu
- College of Environmental Science and Engineering, Yangzhou University, Yangzhou 225009, PR China
| | - Zeyu Liu
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Yishun Zhang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Fan Zhang
- School of Geographic Sciences, East China Normal University, Shanghai 200241, PR China
| | - Caiqing Yan
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Yingjun Chen
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP(3)), Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China.
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Murphy BN, Sonntag D, Seltzer KM, Pye HOT, Allen C, Murray E, Toro C, Gentner DR, Huang C, Jathar S, Li L, May AA, Robinson AL. Reactive organic carbon air emissions from mobile sources in the United States. ATMOSPHERIC CHEMISTRY AND PHYSICS 2023; 23:13469-13483. [PMID: 38516559 PMCID: PMC10953806 DOI: 10.5194/acp-23-13469-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Mobile sources are responsible for a substantial controllable portion of the reactive organic carbon (ROC) emitted to the atmosphere, especially in urban environments of the United States. We update existing methods for calculating mobile source organic particle and vapor emissions in the United States with over a decade of laboratory data that parameterize the volatility and organic aerosol (OA) potential of emissions from on-road vehicles, nonroad engines, aircraft, marine vessels, and locomotives. We find that existing emission factor information from Teflon filters combined with quartz filters collapses into simple relationships and can be used to reconstruct the complete volatility distribution of ROC emissions. This new approach consists of source-specific filter artifact corrections and state-of-the-science speciation including explicit intermediate-volatility organic compounds (IVOCs), yielding the first bottom-up volatility-resolved inventory of US mobile source emissions. Using the Community Multiscale Air Quality model, we estimate mobile sources account for 20 %-25 % of the IVOC concentrations and 4.4 %-21.4 % of ambient OA. The updated emissions and air quality model reduce biases in predicting fine-particle organic carbon in winter, spring, and autumn throughout the United States (4.3 %-11.3 % reduction in normalized bias). We identify key uncertain parameters that align with current state-of-the-art research measurement challenges.
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Affiliation(s)
- Benjamin N. Murphy
- Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, United States
| | - Darrell Sonntag
- Department of Civil and Construction Engineering, Brigham Young University, Provo, UT 84602, United States
| | - Karl M. Seltzer
- Office of Air Quality Planning and Standards, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, United States
| | - Havala O. T. Pye
- Center for Environmental Measurement and Modeling, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, United States
| | - Christine Allen
- General Dynamics Information Technology, 79 T.W. Alexander Drive, Research Triangle Park, NC 27709, United States
| | - Evan Murray
- Office of Transportation and Air Quality, U.S. Environmental Protection Agency, Ann Arbor, MI 48105, United States
| | - Claudia Toro
- Office of Transportation and Air Quality, U.S. Environmental Protection Agency, Ann Arbor, MI 48105, United States
| | - Drew R. Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, United States
| | - Cheng Huang
- State Environmental Protection Key Laboratory of Cause and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai, 200233, China
| | - Shantanu Jathar
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO 80523, United States
| | - Li Li
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT 06511, United States
| | - Andrew A. May
- Department of Civil, Environmental and Geodetic Engineering, The Ohio State University, Columbus, OH 43210, United States
| | - Allen L. Robinson
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA15213, United States
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Chen P, Wang Z, Zhang Y, Guo T, Li Y, Hopke PK, Li X. Volatility distribution of primary organic aerosol emissions from household crop waste combustion in China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 323:121353. [PMID: 36842623 DOI: 10.1016/j.envpol.2023.121353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/21/2023] [Accepted: 02/23/2023] [Indexed: 06/18/2023]
Abstract
Biomass-burning emissions are a significant source of primary organic aerosol (POA). Volatility is one of the most important physical properties of organic aerosol (OA). Dilution and thermodenuder (TD) measurements were used to investigate the volatility of POA from household crop waste combustion in China. Between 10% and 30% of the POA desorbed when diluted from 20:1 to 120:1, while 10%-40% of POA evaporated in the TD when heated to 150 °C. Thus, a considerable proportion of the POA emissions were volatile. A dynamic mass transfer model was applied to derived volatility distributions of POA based on TD data. A best fit volatility distributions for POA and associated mass accommodation coefficients (α), and the enthalpy of vaporization (ΔHvap) were presented. The emissions factors and volatility distribution of POA emission from household crop waste combustion in this study can be used to improve emission inventories and simulate gas-particle partitioning of organic aerosol in chemical transport models.
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Affiliation(s)
- Peng Chen
- School of Space and Environment, Beihang University, Beijing, 100191, China
| | - Zihao Wang
- School of Space and Environment, Beihang University, Beijing, 100191, China
| | - Yangmei Zhang
- State Key Laboratory of Severe Weather/Key Laboratory of Atmospheric Chemistry of China Meteorological Administration, Chinese Academy of Meteorological Sciences, Beijing, 100081, China
| | - Tailun Guo
- School of Space and Environment, Beihang University, Beijing, 100191, China
| | - Youxuan Li
- School of Space and Environment, Beihang University, Beijing, 100191, China
| | - Philip K Hopke
- Department of Public Health Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY, 14642, USA; Institute for a Sustainable Environemnt, Clarkson University, Potsdam, NY, 13699, USA
| | - Xinghua Li
- School of Space and Environment, Beihang University, Beijing, 100191, China.
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Shen X, Che H, Lv T, Wu B, Cao X, Li X, Zhang H, Hao X, Zhou Q, Yao Z. Real-world emission characteristics of semivolatile/intermediate-volatility organic compounds originating from nonroad construction machinery in the working process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159970. [PMID: 36347292 DOI: 10.1016/j.scitotenv.2022.159970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 10/26/2022] [Accepted: 11/01/2022] [Indexed: 06/16/2023]
Abstract
Detailed emission characterization of semivolatile/intermediate-volatility organic compounds (S/IVOCs) originating from nonroad construction machines (NRCMs) remains lacking in China. Twenty-one NRCMs were evaluated with a portable emission measurement system in the working process. Gas phase S/IVOCs were collected by Tenax TA tubes and analyzed via thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). Particle phase S/IVOCs were collected by quartz filters and analyzed via GC-MS. The average emission factors (EFs) for fuel-based total (gas + particle phase) IVOCs and SVOCs of the assessed NRCMs were 221.45 ± 194.60 and 11.68 ± 10.67 mg/kg fuel, respectively. Compared to excavators, the average IVOC and SVOC EFs of loaders were 1.32 and 1.55 times higher, respectively. Compared to the working mode, the average IVOC EFs under the moving mode (only moving forward or backward) were 1.28 times higher. The IVOC and SVOC EFs for excavators decreased by 69.06% and 38.37%, respectively, from China II to China III. These results demonstrate the effectiveness of emission control regulations. In regard to individual NRCMs, excavators and loaders were affected differently by emission standards. The volatility distribution demonstrated that IVOCs and SVOCs were dominated by gas- and particle-phase compounds, respectively. The mode of operation also affected S/IVOC gas-particle partitioning. Combined with previous studies, the mechanical type significantly affected the volatility distribution of IVOCs. IVOCs from higher volatile fuels are more distributed in the high-volatility interval. The total secondary organic aerosol (SOA) production potential was 104.36 ± 79.67 mg/kg fuel, which originated from VOCs (19.98%), IVOCs (73.87%), and SVOCs (6.15%). IVOCs were a larger SOA precursor than VOCs and SVOCs. In addition, normal (n-) alkanes were suitably correlated with IVOCs, which may represent a backup solution to quantify IVOC EFs. This work provides experimental data support for the refinement of the emission characteristics and emission inventories of S/IVOCs originating from NRCMs.
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Affiliation(s)
- Xianbao Shen
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Hongqian Che
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Tiantian Lv
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Bobo Wu
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Xinyue Cao
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Xin Li
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Hanyu Zhang
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Xuewei Hao
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Qi Zhou
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Zhiliang Yao
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China.
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He X, Zheng X, You Y, Zhang S, Zhao B, Wang X, Huang G, Chen T, Cao Y, He L, Chang X, Wang S, Wu Y. Comprehensive chemical characterization of gaseous I/SVOC emissions from heavy-duty diesel vehicles using two-dimensional gas chromatography time-of-flight mass spectrometry. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 305:119284. [PMID: 35436508 DOI: 10.1016/j.envpol.2022.119284] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 03/10/2022] [Accepted: 04/07/2022] [Indexed: 06/14/2023]
Abstract
Intermediate-volatility and semi-volatile organic compounds (I/SVOCs) are key precursors of secondary organic aerosol (SOA). However, the comprehensive characterization of I/SVOCs has long been an analytical challenge. Here, we develop a novel method of speciating and quantifying I/SVOCs using two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-ToF-MS) by constructing class-screening programs based on their characteristic fragments and mass spectrum patterns. Using this new approach, we then present a comprehensive analysis of gaseous I/SVOC emissions from heavy-duty diesel vehicles (HDDVs). Over three-thousand compounds are identified and classified into twenty-one categories. The dominant compound groups of I/SVCOs emitted by HDDVs are alkanes (including normal and branched alkanes, 37-66%), benzylic alcohols (7-20%), alkenes (3-11%), cycloalkanes (3-9%), and benzylic ketones (1-4%). Oxygenated I/SVOCs (O-I/SVOCs, e.g., benzylic alcohols and ketones) are first quantified and account for >20% of the total I/SVOC mass. Advanced aftertreatment devices largely reduce the total I/SVOC emissions but increase the proportion of O-I/SVOCs. With the speciation data, we successfully map the I/SVOCs into the two-dimensional volatility basis set space, which facilitates a better estimation of SOA. As aging time goes by, approximate 45% difference between the two scenarios after seven-day aging is observed, which confirms the significant impact of speciated I/SVOC emission data on SOA prediction.
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Affiliation(s)
- Xiao He
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Xuan Zheng
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
| | - Yan You
- National Observation and Research Station of Coastal Ecological Environments in Macao, Macao Environmental Research Institute, Macau University of Science and Technology, Macao SAR 999078, China
| | - Shaojun Zhang
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Bin Zhao
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China
| | - Xuan Wang
- School of Energy and Environment, City University of Hong Kong, Hong Kong SAR, China
| | - Guanghan Huang
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China
| | - Ting Chen
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China
| | - Yihuan Cao
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China
| | - Liqiang He
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China
| | - Xing Chang
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Shuxiao Wang
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Ye Wu
- School of Environment, State Key Joint Laboratory of Environment Simulation and Pollution Control, Tsinghua University, Beijing 100084, China; Beijing Laboratory of Environmental Frontiers Technologies, Beijing 100084, China
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8
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Yao B, Ma A, Feng R, Shen X, Zhang M, Yao Y. A Deep Learning Framework About Traffic Flow Forecasting for Urban Traffic Emission Monitoring System. Front Public Health 2022; 9:804298. [PMID: 35155353 PMCID: PMC8825479 DOI: 10.3389/fpubh.2021.804298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 12/10/2021] [Indexed: 11/13/2022] Open
Abstract
As urban traffic pollution continues to increase, there is an urgent need to build traffic emission monitoring and forecasting system for the urban traffic construction. The traffic emission monitoring and forecasting system's core is the prediction of traffic emission's evolution. And the traffic flow prediction on the urban road network contributes greatly to the prediction of traffic emission's evolution. Due to the complex non-Euclidean topological structure of traffic networks and dynamic heterogeneous spatial-temporal correlations of traffic conditions, it is difficult to obtain satisfactory prediction results with less computation cost. To figure these issues out, a novel deep learning traffic flow forecasting framework is proposed in this paper, termed as Ensemble Attention based Graph Time Convolutional Networks (EAGTCN). More specifically, each component of our model contains two major blocks: (1) the global spatial patterns are captured by the spatial blocks which are fused by the Graph Convolution Network (GCN) and spatial ensemble attention layer; (2) the temporal patterns are captured by the temporal blocks which are composed by the Time Convolution Net (TCN) and temporal ensemble attention layers. Experiments on two real-world datasets demonstrate that our model obtains more accurate prediction results than the state-of-the-art baselines at less computation expense especially in the long-term prediction situation.
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Affiliation(s)
- Baozhen Yao
- State Key Laboratory of Structural Analysis for Industrial Equipment, School of Automotive Engineering, Dalian University of Technology, Dalian, China
| | - Ankun Ma
- State Key Laboratory of Structural Analysis for Industrial Equipment, School of Automotive Engineering, Dalian University of Technology, Dalian, China
| | - Rui Feng
- State Key Laboratory of Structural Analysis for Industrial Equipment, School of Automotive Engineering, Dalian University of Technology, Dalian, China
| | | | - Mingheng Zhang
- State Key Laboratory of Structural Analysis for Industrial Equipment, School of Automotive Engineering, Dalian University of Technology, Dalian, China
| | - Yansheng Yao
- School of Mechanical and Electrical Engineering, Anhui Jianzhu University, Hefei, China
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9
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Bessagnet B, Allemand N, Putaud JP, Couvidat F, André JM, Simpson D, Pisoni E, Murphy BN, Thunis P. Emissions of Carbonaceous Particulate Matter and Ultrafine Particles from Vehicles—A Scientific Review in a Cross-Cutting Context of Air Pollution and Climate Change. APPLIED SCIENCES-BASEL 2022; 12:1-52. [PMID: 35529678 PMCID: PMC9067409 DOI: 10.3390/app12073623] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Airborne particulate matter (PM) is a pollutant of concern not only because of its adverse effects on human health but also on visibility and the radiative budget of the atmosphere. PM can be considered as a sum of solid/liquid species covering a wide range of particle sizes with diverse chemical composition. Organic aerosols may be emitted (primary organic aerosols, POA), or formed in the atmosphere following reaction of volatile organic compounds (secondary organic aerosols, SOA), but some of these compounds may partition between the gas and aerosol phases depending upon ambient conditions. This review focuses on carbonaceous PM and gaseous precursors emitted by road traffic, including ultrafine particles (UFP) and polycyclic aromatic hydrocarbons (PAHs) that are clearly linked to the evolution and formation of carbonaceous species. Clearly, the solid fraction of PM has been reduced during the last two decades, with the implementation of after-treatment systems abating approximately 99% of primary solid particle mass concentrations. However, the role of brown carbon and its radiative effect on climate and the generation of ultrafine particles by nucleation of organic vapour during the dilution of the exhaust remain unclear phenomena and will need further investigation. The increasing role of gasoline vehicles on carbonaceous particle emissions and formation is also highlighted, particularly through the chemical and thermodynamic evolution of organic gases and their propensity to produce particles. The remaining carbon-containing particles from brakes, tyres and road wear will still be a problem even in a future of full electrification of the vehicle fleet. Some key conclusions and recommendations are also proposed to support the decision makers in view of the next regulations on vehicle emissions worldwide.
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Affiliation(s)
- Bertrand Bessagnet
- Joint Research Centre, European Commission, 21027 Ispra, Italy
- Correspondence: or
| | | | | | - Florian Couvidat
- INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte, France
| | | | - David Simpson
- EMEP MSC-W, Norwegian Meteorological Institute, 0313 Oslo, Norway
- Department Space, Earth & Environment, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden
| | - Enrico Pisoni
- Joint Research Centre, European Commission, 21027 Ispra, Italy
| | - Benjamin N. Murphy
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, Durham, NC 27711, USA
| | - Philippe Thunis
- Joint Research Centre, European Commission, 21027 Ispra, Italy
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10
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Ling Z, Wu L, Wang Y, Shao M, Wang X, Huang W. Roles of semivolatile and intermediate-volatility organic compounds in secondary organic aerosol formation and its implication: A review. J Environ Sci (China) 2022; 114:259-285. [PMID: 35459491 DOI: 10.1016/j.jes.2021.08.055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 08/31/2021] [Accepted: 08/31/2021] [Indexed: 06/14/2023]
Abstract
Secondary organic aerosol (SOA) is a very important component of fine particulate matter (PM2.5) in the atmosphere. However, the simulations of SOA, which could help to elucidate the detailed mechanism of SOA formation and quantify the roles of various precursors, remains unsatisfactory, as SOA levels are frequently underestimated. It has been found that the performance of SOA formation models can be significantly improved by incorporating the emission and evolution of semivolatile and intermediate-volatility organic compounds (S/IVOCs). In order to explore the roles of S/IVOCs in SOA formation, this study reviews some simulation models which could consider S/IVOCs for SOA formation as well as the development of emission inventories of S/IVOCs and S/IVOC modules for SOA formation. In addition, the future research directions for simulations of the effect of S/IVOCs on SOA formation are suggested.
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Affiliation(s)
- Zhenhao Ling
- School of Atmospheric Sciences, Sun Yat-sen University, Key Laboratory of Tropical Atmosphere-Ocean System, Ministry of Education, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Liqing Wu
- School of Atmospheric Sciences, Sun Yat-sen University, Key Laboratory of Tropical Atmosphere-Ocean System, Ministry of Education, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
| | - Yonghong Wang
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Min Shao
- Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Institute for Environmental and Climate Research, Jinan University, Guangzhou 510632, China
| | - Xuemei Wang
- Guangdong-Hongkong-Macau Joint Laboratory of Collaborative Innovation for Environmental Quality, Institute for Environmental and Climate Research, Jinan University, Guangzhou 510632, China.
| | - Weiwen Huang
- School of Atmospheric Sciences, Sun Yat-sen University, Key Laboratory of Tropical Atmosphere-Ocean System, Ministry of Education, and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 519082, China
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11
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Wong YK, Huang XHH, Cheng YY, Yu JZ. Estimating primary vehicular emission contributions to PM 2.5 using the Chemical Mass Balance model: Accounting for gas-particle partitioning of organic aerosols and oxidation degradation of hopanes. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 291:118131. [PMID: 34530241 DOI: 10.1016/j.envpol.2021.118131] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/25/2021] [Accepted: 09/06/2021] [Indexed: 06/13/2023]
Abstract
Particulate matter emitted from vehicles (PMvehicle) represents a major air pollution source in urban areas. Ambient measurements of hopanes and elemental carbon have traditionally been coupled with the Chemical Mass Balance (CMB) model to quantify the contributions to fine PM from diesel and gasoline vehicular emissions (VE). The organic carbon part of PMvehicle, however, undergoes gas-particle partitioning and oxidation degradation as VE move from exhaust pipe to receptor sites. This creates an issue of deviation from mass conservation in the utility of CMB. The impact of this issue on quantifying PMvehicle has remained largely uncharacterized. In this study, we incorporate in CMB the gas-particle partitioning of VE organic aerosols and hopane oxidation, which is equivalent to adopting dynamic VE source profiles. The modified version of CMB is applied to quantify primary PMvehicle contributions at a roadside and a general urban site in Hong Kong. For the roadside site, the modified CMB reports predominant PMvehicle by diesel VE, a result consistent with previous studies. For the general urban site, the apportioned gasoline contribution by the modified CMB is tripled (0.8 ± 0.5 vs. 2.7 ± 2.1 μg/m3) while the diesel contribution is reduced by one third (1.7 ± 1.2 vs. 1.1 ± 1.2 μg/m3), producing a gasoline-diesel split significantly different from that by traditional CMB (1:2 vs. 5:2). Our work strongly indicates that a static representation of VE source profiles in CMB modeling would create flawed PMvehicle estimation and demonstrates the necessity of considering gas-particle partitioning of organic aerosol and hopane oxidation degradation.
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Affiliation(s)
- Yee Ka Wong
- Division of Environment & Sustainability, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong
| | - X H Hilda Huang
- Division of Environment & Sustainability, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Yuk Ying Cheng
- Department of Chemistry, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jian Zhen Yu
- Division of Environment & Sustainability, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong; Department of Chemistry, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong.
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12
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Shen X, Hao J, Kong L, Shi Y, Cao X, Shi J, Yao Z, Li X, Wu B, Xu Y, He K. Variation characteristics of fine particulate matter and its components in diesel vehicle emission plumes. J Environ Sci (China) 2021; 107:138-149. [PMID: 34412776 DOI: 10.1016/j.jes.2021.01.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 01/31/2021] [Accepted: 01/31/2021] [Indexed: 06/13/2023]
Abstract
A rapid reaction occurs near the exhaust nozzle when vehicle emissions contact the air. Twenty diesel vehicles were studied using a new multipoint sampling system that is suitable for studying the exhaust plume near the exhaust nozzle. The variation characteristics of fine particle matter (PM2.5) and its components in diesel vehicle exhaust plumes were analyzed. The PM2.5 emissions gradually increased with increasing distance from the nozzle in the plume. Elemental carbon emissions remained basically unchanged, organic carbon and total carbon (TC) increased with increasing distance. The concentrations of SO42-, NO3- and NH4+ (SNA) directly emitted by the vehicles were very low but increased rapidly in the exhaust plume. The selective catalytic reduction (SCR) reduced 42.7% TC, 40% NO3- emissions, but increased 104% SO42- and 36% NH4+ emissions, respectively. In summary, the SCR reduced 29% primary PM2.5 emissions for the tested diesel vehicles. The NH4NO3 particle formation maybe more important in the plume, and there maybe other forms of formation of NH4+ (eg. NH4Cl). The generation of secondary organic carbon (SOC) plays a leading role in the generation of secondary PM2.5. The SCR enhanced the formation of SOC and SNA in the plume, but comprehensive analysis shows that the SCR more enhanced the SNA formation in the plume, which is mainly new particles formation process. The inconsistency between secondary organic aerosol (SOA) and primary organic aerosol definitions is one of the important reasons for the difference between SOA simulation and observation.
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Affiliation(s)
- Xianbao Shen
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Jiateng Hao
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Lei Kong
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Yue Shi
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Xinyue Cao
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Jiacheng Shi
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Zhiliang Yao
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China.
| | - Xin Li
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Bobo Wu
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Yiming Xu
- State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China; Key Laboratory of Cleaner Production and Integrated Resource Utilization of China National Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Kebin He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China; State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
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13
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Hao Y, Deng S, Qiu Z, Lu Z, Song H, Yang N. Chemical characterization of PM 2.5 emitted from China IV and China V light-duty vehicles in China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 783:147101. [PMID: 34088135 DOI: 10.1016/j.scitotenv.2021.147101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 04/07/2021] [Accepted: 04/08/2021] [Indexed: 06/12/2023]
Abstract
This study reported the emission factors (EFs) and detailed chemical compositions of PM2.5 collected from China IV and China V light-duty vehicles (LDVs) through dynamometer test. The China IV LDVs containing 4 gasoline vehicles (GVs) and 4 natural gas vehicles (NGVs) had port fuel injection (PFI) engines, while the China V LDVs included 2 GVs with PFI engines and 2 GVs with gasoline direct injection (GDI) engines. The average EFs of PM2.5 were 1.90 ± 0.70 mg km-1, 1.44 ± 0.29 mg km-1, and 0.56 ± 0.05 mg km-1 for China IV GVs, China IV NGVs, and China V GVs, respectively. PM2.5 profiles of LDVs were characterized by abundant carbon species (60.59-68.58%) with low amounts of water soluble ions (WSIs, 6.96-16.37%) and elements (5.20-7.53%). In general, the EFs of PM2.5 constituents including organic carbon (OC), elemental carbon (EC), WSIs, and elements were reduced obviously by strengthening emission standards from China IV to China V. While the contributions of most WSIs and elements to PM2.5 increased as vehicle technology improved. Furthermore, the EFs of PM2.5 components from China IV LDVs also decreased when shifting fuels from gasoline to natural gas. While the fractions of OC, WSIs and most elements in PM2.5 increased due to the highest reduction rate of EC mass. For China V LDVs, GDI vehicles emitted less OC but more EC compared to PFI vehicles, and the EFs of most WSIs and elements also increased. Overall, GDI vehicles exhibited lower fractions OC and WSIs but higher contents of EC and elements in PM2.5. Besides, PM2.5 and its chemical species were heavily dependent on vehicle's driving patterns. The average EFs of PM2.5 components under aggressive driving pattern increased significantly compared to those under moderate driving pattern.
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Affiliation(s)
- Yanzhao Hao
- School of Automobile, Chang'an University, Xi'an 710064, China.
| | - Shunxi Deng
- School of Water and Environment, Chang'an University, Xi'an 710064, China; Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an 710064, China
| | - Zhaowen Qiu
- School of Automobile, Chang'an University, Xi'an 710064, China
| | - Zhenzhen Lu
- School of Water and Environment, Chang'an University, Xi'an 710064, China; Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an 710064, China
| | - Hui Song
- School of Civil Engineering, Chang'an University, Xi'an 710064, China
| | - Naiwang Yang
- Xi'an Environmental Protection Bureau, Xi'an 710054, China
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14
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Liu Y, Li Y, Yuan Z, Wang H, Sha Q, Lou S, Liu Y, Hao Y, Duan L, Ye P, Zheng J, Yuan B, Shao M. Identification of two main origins of intermediate-volatility organic compound emissions from vehicles in China through two-phase simultaneous characterization. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 281:117020. [PMID: 33813191 DOI: 10.1016/j.envpol.2021.117020] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 03/20/2021] [Accepted: 03/23/2021] [Indexed: 06/12/2023]
Abstract
Intermediate-volatility organic compounds (IVOCs) emitted from vehicles are generally in the gas phase but may partly partition into particle phase when measured under ambient temperature. To have a complete and accurate picture of IVOC emissions from vehicles, gas- and particle-phase IVOCs from a fleet of gasoline and diesel vehicles were simultaneously characterized by dynamometer testing in Guangzhou, China. The total IVOC emission factors of the diesel vehicles were approximately 16 times those of the gasoline vehicles, and IVOCs were mainly concentrated in the particle phase in the form of the unresolved complex mixture (UCM). The chemical compositions and volatility distributions of the gas-phase IVOCs differed much between gasoline and diesel vehicles, but were similar to those of their respective fuel content. This indicated that vehicle fuel is the main origin for the gas-phase IVOC emissions from vehicles. In comparison, the chemical compositions of the particle-phase IVOCs from gasoline and diesel vehicles were similar and close to lubricating oil content, implying that lubricating oil plays an important role in contributing to particle-phase IVOCs. The highest IVOC fraction in the particle phase occurred from B16-B18 volatility bins, overall accounting for more than half of the particle-phase IVOCs for both the gasoline and diesel vehicles. A conceptual model was developed to articulate the distributions of lubricating oil contents and their evaporation and nucleation/adsorption capabilities in the different volatility bins. The IVOCs-produced secondary organic aerosol (SOA) were 1.4-2.6 and 3.9-11.7 times POAs emitted from the gasoline and diesel vehicles, respectively. The tightening of emission standards had not effectively reduced IVOC emissions and the SOA production until the implementation of China VI emission standard. This underscores the importance of accelerating the promotion of the latest emission standard to alleviate pollution from vehicles in China.
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Affiliation(s)
- Yuanxiang Liu
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China
| | - Yingjie Li
- State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai, 200233, China
| | - Zibing Yuan
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China.
| | - Hongli Wang
- State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai, 200233, China.
| | - Qing'e Sha
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, 511443, China
| | - Shengrong Lou
- State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai, 200233, China
| | - Yuehui Liu
- State Environmental Protection Key Laboratory of the Cause and Prevention of Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai, 200233, China
| | - Yuqi Hao
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China
| | - Lejun Duan
- School of Environment and Energy, South China University of Technology, Guangzhou, 510006, China
| | - Penglin Ye
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, China
| | - Junyu Zheng
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, 511443, China
| | - Bin Yuan
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, 511443, China
| | - Min Shao
- Institute for Environmental and Climate Research, Jinan University, Guangzhou, 511443, China
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15
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Fujitani Y, Sato K, Tanabe K, Takahashi K, Hoshi J, Wang X, Chow JC, Watson JG. Volatility Distribution of Organic Compounds in Sewage Incineration Emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14235-14245. [PMID: 33108869 DOI: 10.1021/acs.est.0c04534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Intermediate volatility and semivolatile organic compounds (IVOC/SVOC) are important precursors of secondary organic aerosol (SOA) while SVOC is an important contributor to primary organic aerosol (POA). However, combustion emissions data for volatility classes are limited. This study reports the gas and particle emissions that were sampled with various dilution factors from a sewage sludge incinerator burning fuel oil. Volatility distributions were determined using measurements from online mass spectrometry and offline organic compound analyses. In the low volatility organic compound (LVOC) to IVOC range, volatility bins with organic saturation concentrations of 10-100 μg m-3 were most abundant, which was due to organic acids generated from sludge burning. Organic aerosol (OA) emission factors (EFOA) increased 1.4 times after cooling to ambient temperatures in comparison to those of the samples from the hot stack. Upon further isothermal dilution at 25 °C, the EFOA decreased while organic gas phase EFs increased with increasing dilution. Phase partitioning in volatility bins with saturation concentrations of 10-100 μg m-3 was sensitive to isothermal dilution that influenced the EFs. Therefore, gas- and particle-phase measurements alone cannot constrain EFs for these volatility classes. Low dilution factors may overestimate the particle phase and underestimate the gas phase EFs compared with real-world emission conditions.
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Affiliation(s)
- Yuji Fujitani
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
| | - Kei Sato
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
| | - Kiyoshi Tanabe
- National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-8506, Japan
| | | | - Junya Hoshi
- Tokyo Metropolitan Research Institute for Environmental Protection, Tokyo 136-0075, Japan
| | - Xiaoliang Wang
- Division of Atmospheric Sciences, Desert Research Institute, Reno, Nevada 89512, United States
| | - Judith C Chow
- Division of Atmospheric Sciences, Desert Research Institute, Reno, Nevada 89512, United States
| | - John G Watson
- Division of Atmospheric Sciences, Desert Research Institute, Reno, Nevada 89512, United States
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16
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Xu R, Alam MS, Stark C, Harrison RM. Behaviour of traffic emitted semi-volatile and intermediate volatility organic compounds within the urban atmosphere. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137470. [PMID: 32325566 DOI: 10.1016/j.scitotenv.2020.137470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/23/2020] [Accepted: 02/19/2020] [Indexed: 06/11/2023]
Abstract
Particulate matter originated from traffic has attracted major interest over the last few years. The semi-volatile organic component of the particles may evaporate with dispersion away from the emission source, creating vapour which may oxidise to form secondary organic aerosol. Air samples were collected from a street canyon, the adjacent park and an urban background site during the winter-spring period in central London, UK. Emissions of semi-volatile organic compounds (SVOCs) and intermediate volatility organic compounds (IVOCs) ranging from C10 to C36 in both the gas phase and particle phase were measured by using thermal desorption coupled to comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry (TD-GC × GC-ToF-MS). Main compound groups identified and quantified were grouped alkanes (n-alkanes and branched alkanes), monocyclic alkanes, bicyclic alkanes and monocyclic aromatics. The carbon preference index (CPI) of n-alkanes was estimated to distinguish the emission sources. Pearson correlations between I/SVOCs and traffic tracers (black carbon, NOx and benzene) in different locations were compared to analyse the influence of this emission source. The results indicate that while the major emission source at the roadside site is traffic, the lower correlations at background sites are indicative of other source contributions and/or differential reactivity of compounds. Gas-particle phase partitioning of n-alkanes is evaluated and compared between sites. The potential influence of gas phase I/SVOCs upon OH reactivity and secondary organic aerosol (SOA) formation is estimated and found to be relatively small.
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Affiliation(s)
- Ruixin Xu
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Mohammed S Alam
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Christopher Stark
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Roy M Harrison
- Division of Environmental Health and Risk Management, School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
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17
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Lu Q, Murphy BN, Qin M, Adams PJ, Zhao Y, Pye HOT, Efstathiou C, Allen C, Robinson AL. Simulation of organic aerosol formation during the CalNex study: updated mobile emissions and secondary organic aerosol parameterization for intermediate-volatility organic compounds. ATMOSPHERIC CHEMISTRY AND PHYSICS 2020; 20:4313-4332. [PMID: 32461753 PMCID: PMC7252505 DOI: 10.5194/acp-20-4313-2020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We describe simulations using an updated version of the Community Multiscale Air Quality model version 5.3 (CMAQ v5.3) to investigate the contribution of intermediate-volatility organic compounds (IVOCs) to secondary organic aerosol (SOA) formation in southern California during the CalNex study. We first derive a model-ready parameterization for SOA formation from IVOC emissions from mobile sources. To account for SOA formation from both diesel and gasoline sources, the parameterization has six lumped precursor species that resolve both volatility and molecular structure (aromatic versus aliphatic). We also implement new mobile-source emission profiles that quantify all IVOCs based on direct measurements. The profiles have been released in SPECIATE 5.0. By incorporating both comprehensive mobile-source emission profiles for semivolatile organic compounds (SVOCs) and IVOCs and experimentally constrained SOA yields, this CMAQ configuration best represents the contribution of mobile sources to urban and regional ambient organic aerosol (OA). In the Los Angeles region, gasoline sources emit 4 times more non-methane organic gases (NMOGs) than diesel sources, but diesel emits roughly 3 times more IVOCs on an absolute basis. The revised model predicts all mobile sources (including on- and off-road gasoline, aircraft, and on- and off-road diesel) contribute ~ 1 μgm-3 to the daily peak SOA concentration in Pasadena. This represents a ~ 70% increase in predicted daily peak SOA formation compared to the base version of CMAQ. Therefore, IVOCs in mobile-source emissions contribute almost as much SOA as traditional precursors such as single-ring aromatics. However, accounting for these emissions in CMAQ does not reproduce measurements of either ambient SOA or IVOCs. To investigate the potential contribution of other IVOC sources, we performed two exploratory simulations with varying amounts of IVOC emissions from nonmobile sources. To close the mass balance of primary hydrocarbon IVOCs, IVOCs would need to account for 12% of NMOG emissions from nonmobile sources (or equivalently 30.7 t d-1 in the Los Angeles-Pasadena region), a value that is well within the reported range of IVOC content from volatile chemical products. To close the SOA mass balance and also explain the mildly oxygenated IVOCs in Pasadena, an additional 14.8% of nonmobile-source NMOG emissions would need to be IVOCs (assuming SOA yields from the mobile IVOCs apply to nonmobile IVOCs). However, an IVOC-to-NMOG ratio of 26.8% (or equivalently 68.5 t d-1 in the Los Angeles-Pasadena region) for nonmobile sources is likely unrealistically high. Our results highlight the important contribution of IVOCs to SOA production in the Los Angeles region but underscore that other uncertainties must be addressed (multigenerational aging, aqueous chemistry and vapor wall losses) to close the SOA mass balance. This research also highlights the effectiveness of regulations to reduce mobile-source emissions, which have in turn increased the relative importance of other sources, such as volatile chemical products.
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Affiliation(s)
- Quanyang Lu
- Center of Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
- Oak Ridge Institute for Science and Education (ORISE) Research Participation Program at the Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Benjamin N Murphy
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Momei Qin
- Oak Ridge Institute for Science and Education (ORISE) Research Participation Program at the Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Peter J Adams
- Center of Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Yunliang Zhao
- Center of Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Havala O T Pye
- Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Christos Efstathiou
- General Dynamics Information Technology Research Triangle Park, North Carolina, USA
| | - Chris Allen
- General Dynamics Information Technology Research Triangle Park, North Carolina, USA
| | - Allen L Robinson
- Center of Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, USA
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18
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Seasonal and Long-Term Trend of on-Road Gasoline and Diesel Vehicle Emission Factors Measured in Traffic Tunnels. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10072458] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Emissions of gaseous and particulate pollutants from on-road gasoline and diesel vehicles were measured in a traffic tunnel under real-world driving conditions. Emission factors were attributed to gasoline and diesel vehicles using linear regression against the fraction of fuel consumed by diesel vehicles (% fuelD). We measured 67% higher NOx emissions from gasoline vehicles in winter than in spring (2 versus 1.2 g NO2 kg fuel−1). Emissions of CO, NOx, and particulate matter from diesel vehicles all showed impacts of recent policy changes to reduce emissions from this source. Comparison of our measurements to those of a previous study ~10 years prior in a nearby traffic tunnel on the same highway showed that emission factors for both gasoline and diesel vehicles have fallen by 50–70%. To further confirm this long-term trend, we summarized emission factors measured in previous tunnel studies in the U.S. since the 1990s. More restrictive emission standards are effective at reducing emissions from both diesel and gasoline vehicles, and decreases in observed emissions can be mapped to specific vehicle control policies. The trend of diesel-to-gasoline emission factor ratios revealed changes in the relative importance of vehicle types, though fuel-specific emission factors of NOx and elemental carbon (EC) are still substantially larger (~5–10 times) for diesel vehicles than gasoline vehicles.
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19
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Pirhadi M, Mousavi A, Taghvaee S, Shafer MM, Sioutas C. Semi-volatile components of PM 2.5 in an urban environment: volatility profiles and associated oxidative potential. ATMOSPHERIC ENVIRONMENT (OXFORD, ENGLAND : 1994) 2020; 223:117197. [PMID: 32577088 PMCID: PMC7311065 DOI: 10.1016/j.atmosenv.2019.117197] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The volatility profiles of PM2.5 semi-volatile compounds and relationships to the oxidative potential of urban airborne particles were investigated in central Los Angeles, CA. Ambient and thermodenuded fine (PM2.5) particles were collected during both warm and cold seasons by employing the Versatile Aerosol Concentration Enrichment System (VACES) combined with a thermodenuder. When operated at 50 °C and 100 °C, the VACES/thermodenuder system removed about 50% and 75% of the PM2.5 volume concentration, respectively. Most of the quantified PM2.5 semi-volatile species including organic carbon (OC), water soluble organic carbon (WSOC), polycyclic aromatic hydrocarbons (PAHs), organic acids, n-alkanes, and levoglucosan, as well as inorganic ions (i.e., nitrate, sulfate, and ammonium) exhibited concentration losses in the ranges of 40-66% and 67-92%, respectively, as the thermodenuder temperature increased to 50 °C and 100 °C. Species in the PM2.5 such as elemental carbon (EC) and inorganic elements (including trace metals) were minimally impacted by the heating process - thus can be considered refractory. On average, nearly half of the PM2.5 oxidative potential (as measured by the dichlorodihydrofluorescein (DCFH) alveolar macrophage in vitro assay) was associated with the semi-volatile species removed by heating the aerosols to only 50 °C, highlighting the importance of this quite volatile compartment to the ambient PM2.5 toxicity. The fraction of PM2.5 oxidative potential lost upon heating the aerosols to 100 °C further increased to around 75-85%. Furthermore, we document statistically significant correlations between the PM2.5 oxidative potential and different semi-volatile organic compounds originating from primary and secondary sources, including OC (Rwarm, and Rcold) (0.86, and 0.74), WSOC (0.60, and 0.98), PAHs (0.88, and 0.76), organic acids (0.76, and 0.88), and n-alkanes (0.67, and 0.83) in warm and cold seasons, respectively, while a strong correlation between oxidative potential and levoglucosan, a tracer of biomass burning, was observed only during the cold season (Rcold=0.81).
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Affiliation(s)
- Milad Pirhadi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Amirhosein Mousavi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Sina Taghvaee
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Martin M. Shafer
- University of Wisconsin-Madison, Wisconsin State Laboratory of Hygiene, Madison, WI, USA
| | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
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20
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Hao Y, Gao C, Deng S, Yuan M, Song W, Lu Z, Qiu Z. Chemical characterisation of PM 2.5 emitted from motor vehicles powered by diesel, gasoline, natural gas and methanol fuel. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 674:128-139. [PMID: 31004890 DOI: 10.1016/j.scitotenv.2019.03.410] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 03/25/2019] [Accepted: 03/25/2019] [Indexed: 06/09/2023]
Abstract
Vehicle emissions are affected by factors such as vehicle type, fuel quality, and engine repair. Therefore, mobile source profiles should be established based on a characteristic fleet for a specific region. This study characterised the chemical composition of PM2.5 emitted from motor vehicles that are commonly used in Xi'an through dynamometer tests. The tested fleet included light duty diesel vehicles (LDDVs; eight sample sets), heavy duty diesel vehicles (HDDVs; six sample sets), light duty gasoline vehicles (LDGVs; eight sample sets), one natural gas vehicle (NGV; four sample sets) and one methanol vehicle (MV; two sample sets). Similarities and differences among the source profiles were compared and evaluated. Overall, carbon species (13.14-59.11%) were the major components of PM2.5 for each type of vehicle, and the content of organic carbon (OC) was generally higher than that of elemental carbon (EC). Moreover, NO3- (18.577-220.062 mg·g-1) was the dominant water-soluble ion and the Ca2+ (2.429-17.209 mg·g-1) and Na+ (1.966-20.798 mg·g-1) contents in PM2.5 were high. In terms of elements, the PM2.5 emitted from various types of vehicles consisted of abundant Al (2.183-94.949 mg·g-1), Fe (0.567-12.297 mg·g-1), and Zn (0.659-5.195 mg·g-11). In addition, the PM2.5 profiles were significantly affected by fuel type. In general, emissions from the LDGVs and NGV exhibited higher contents of OC (477.0-479.1 mg·g-1). The greatest fractions of water-soluble ions (32.94%) and total elements (11.74%) were observed in emissions from the NGV and MV, respectively. For the same type of vehicle, the OC/EC ratio was possibly dependent on the emission standards. The PM2.5 emitted from the LDDVs with stricter emission standards exhibited higher OC/EC ratios, whereas the OC/EC ratios displayed a decreasing trend for the LDGVs under more stringent emission standards.
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Affiliation(s)
- Yanzhao Hao
- School of Automobile, Chang'an University, Xi'an 710064, China
| | - Chanjuan Gao
- College of Resources and Environmental Engineering, Jilin Institute of Chemical Technology, Jilin 132022, China; Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an 710064, China
| | - Shunxi Deng
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an 710064, China; School of Environmental Science and Engineering, Chang'an University, Xi'an 710064, China.
| | - Min Yuan
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an 710064, China; School of Environmental Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Wenbin Song
- Xi'an Environmental Protection Bureau, Xi'an 710054, China
| | - Zhenzhen Lu
- Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Chang'an University, Xi'an 710064, China; School of Environmental Science and Engineering, Chang'an University, Xi'an 710064, China
| | - Zhaowen Qiu
- School of Automobile, Chang'an University, Xi'an 710064, China
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21
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Sharma N, Vanderheyden C, Klunder K, Henry CS, Volckens J, Jathar SH. Emerging investigator series: oxidative potential of diesel exhaust particles: role of fuel, engine load, and emissions control. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2019; 21:819-830. [PMID: 30977477 DOI: 10.1039/c8em00571k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Exposure to diesel exhaust particles (DEP) has been linked to adverse human health outcomes. DEPs are reactive and can directly or indirectly lead to oxidative stress, which promotes inflammation in the body. The oxidative potential (OP) of DEPs is not well understood, particularly for combustion with alternative fuels, under different engine loads, and in combination with modern emissions control devices. In this study, we measured the OP of DEPs using a dithiothreitol assay (OP-DTT) from a modern-day non-road diesel engine for two different fuels (conventional diesel and soy-based biodiesel), two different engine loads (idle and 50% load), and with and without an emissions control system. The OP-DTT of DEPs was sensitive to the fuel used and the presence of an emissions control system but not to the engine load. On average, the use of biodiesel resulted in factor of ∼6 reduction in OP-DTT normalized to the DEP mass and a factor of ∼12 reduction in OP-DTT normalized to the fuel consumed. The use of the emissions control, on average, resulted in a factor of ∼6 reduction in OP-DTT normalized to the DEP mass and a three order of magnitude decrease in OP-DTT normalized to the fuel consumed. When studied in conjunction with the DEP composition, the OP-DTT seemed to correlate most strongly with elemental carbon (EC), followed by semi-volatile organic vapors. Assays performed on DEPs where EC was deliberately filtered out suggested that the species responsible for the OP-DTT might be correlated with EC but would need to be water soluble (e.g., quinones). The semi-volatile organic vapors accounted for more than a quarter of the OP-DTT of DEPs collected on the quartz filters. Finally, sensitivity studies performed with a different filter membrane (i.e., Teflon®) and solvent (i.e., dichloromethane) tended to increase the OP-DTT value. OP-DTT is emerging as an important metric for studying the adverse effects of DEPs and PM2.5 on human health; results of this work help define the sources and components of diesel PM2.5 that contribute to OP-DTT.
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Affiliation(s)
- Naman Sharma
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, USA.
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22
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Quantifying Urban Spatial Variations of Anthropogenic VOC Concentrations and Source Contributions with a Mobile Sampling Platform. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16091632. [PMID: 31083299 PMCID: PMC6539943 DOI: 10.3390/ijerph16091632] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 05/01/2019] [Accepted: 05/08/2019] [Indexed: 12/11/2022]
Abstract
Volatile organic compounds (VOCs) are important atmospheric constituents because they contribute to formation of ozone and secondary aerosols, and because some VOCs are toxic air pollutants. We measured concentrations of a suite of anthropogenic VOCs during summer and winter at 70 locations representing different microenvironments around Pittsburgh, PA. The sampling sites were classified both by land use (e.g., high versus low traffic) and grouped based on geographic similarity and proximity. There was roughly a factor of two variation in both total VOC and single-ring aromatic VOC concentrations across the site groups. Concentrations were roughly 25% higher in winter than summer. Source apportionment with positive matrix factorization reveals that the major VOC sources are gasoline vehicles, solvent evaporation, diesel vehicles, and two factors attributed to industrial emissions. While we expected to observe significant spatial variability in the source impacts across the sampling domain, we instead found that source impacts were relatively homogeneous.
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23
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Liu T, Zhou L, Liu Q, Lee BP, Yao D, Lu H, Lyu X, Guo H, Chan CK. Secondary Organic Aerosol Formation from Urban Roadside Air in Hong Kong. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:3001-3009. [PMID: 30790521 DOI: 10.1021/acs.est.8b06587] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Motor vehicle emissions are an important but poorly constrained source of secondary organic aerosol (SOA). Here, we investigated in situ SOA formation from urban roadside air in Hong Kong during winter time using an oxidation flow reactor (OFR), with equivalent atmospheric oxidation ranging from several hours to several days. The campaign-average mass enhancement of OA, nitrate, sulfate, and ammonium upon OFR aging was 7.0, 7.2, 0.8, and 2.6 μg m-3, respectively. To investigate the sources of SOA formation potential, we performed multilinear regression analysis between measured peak SOA concentrations from OFR and the concentrations of toluene that represent motor vehicle emissions and cooking OA from positive matrix factorization (PMF) analysis of ambient OA. Traffic-related SOA precursors contributed 92.3%, 92.4%, and 83.1% to the total SOA formation potential during morning rush hours, noon and early afternoon, and evening meal time, respectively. The SOA production factor (PF) was approximately 5.2 times of primary OA (POA) emission factor (EF) and the secondary particulate matter (PM) PF was approximately 2.6 times of primary particles EF. This study highlights the potential benefit of reducing secondary PM production from motor vehicle emissions in mitigating PM pollutions.
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Affiliation(s)
- Tengyu Liu
- School of Energy and Environment , City University of Hong Kong , Hong Kong , China
| | - Liyuan Zhou
- School of Energy and Environment , City University of Hong Kong , Hong Kong , China
| | - Qianyun Liu
- Division of Environment and Sustainability , Hong Kong University of Science and Technology , Hong Kong , China
| | - Berto P Lee
- School of Energy and Environment , City University of Hong Kong , Hong Kong , China
| | - Dawen Yao
- Department of Civil and Environmental Engineering , The Hong Kong Polytechnic University , Hong Kong , China
| | - Haoxian Lu
- Department of Civil and Environmental Engineering , The Hong Kong Polytechnic University , Hong Kong , China
| | - Xiaopu Lyu
- Department of Civil and Environmental Engineering , The Hong Kong Polytechnic University , Hong Kong , China
| | - Hai Guo
- Department of Civil and Environmental Engineering , The Hong Kong Polytechnic University , Hong Kong , China
| | - Chak K Chan
- School of Energy and Environment , City University of Hong Kong , Hong Kong , China
- City University of Hong Kong Shenzhen Research Institute , Shenzhen 518057 , China
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24
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Liu JM, Du ZY, Gordon M, Liang LL, Ma YL, Zheng M, Cheng Y, He KB. The characteristics of carbonaceous aerosol in Beijing during a season of transition. CHEMOSPHERE 2018; 212:1010-1019. [PMID: 30286530 DOI: 10.1016/j.chemosphere.2018.08.151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/29/2018] [Accepted: 08/29/2018] [Indexed: 06/08/2023]
Abstract
Carbonaceous aerosol was measured during fall of 2010 in Beijing. Daily variation of organic carbon (OC) was found to coincide with that of relative humidity (RH), and the OC to elemental carbon (EC) ratios were more than doubled during the more humid periods (RH above 0.75) compared to other conditions. This large increase in OC/EC could not be explained by the variations of primary biomass burning emissions but was accompanied by a five-fold increase in the sulfate to EC ratio. It was then inferred that secondary organic aerosol (SOA) formation was enhanced under the more humid conditions, presumably through aqueous-phase processes. This enhanced SOA formation might be partially associated with particles externally mixed with black carbon, as indicated by the RH-dependent relationships between aerosol optical attenuation and EC loading. In addition, organic aerosols exhibited different properties between the more humid and the other periods, such that they were less volatile and charred more significantly during thermal-optical analysis in the former case. These differences coincided with the evidence of enhanced SOA formation under the more humid conditions. This study highlights the necessity of incorporating aqueous-phase chemistry into air quality models for SOA.
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Affiliation(s)
- Jiu-Meng Liu
- School of Environment, Harbin Institute of Technology, Harbin, China
| | - Zhen-Yu Du
- National Research Center for Environmental Analysis and Measurement, Beijing, China
| | - Mark Gordon
- Department of Earth and Space Science and Engineering, York University, Toronto, Ontario, Canada
| | - Lin-Lin Liang
- State Key Laboratory of Severe Weather and Key Laboratory for Atmospheric Chemistry of CMA, Chinese Academy of Meteorological Sciences, Beijing, China
| | - Yong-Liang Ma
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China
| | - Mei Zheng
- College of Environmental Sciences and Engineering, Peking University, Beijing, China
| | - Yuan Cheng
- School of Environment, Harbin Institute of Technology, Harbin, China.
| | - Ke-Bin He
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing, China
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25
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Xue J, Li Y, Peppers J, Wan C, Kado NY, Green PG, Young TM, Kleeman MJ. Ultrafine Particle Emissions from Natural Gas, Biogas, and Biomethane Combustion. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:13619-13628. [PMID: 30296061 DOI: 10.1021/acs.est.8b04170] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Biogas and biomethane (=purified biogas) are major renewable fuels that play a pivotal role in the evolving global energy economy. Here, we measure ultrafine particle (UFP; Dp (particle diameter) < 100 nm) emissions from the combustion of biomethane and biogas produced from five different representative sources: two food waste digesters, two dairy waste digesters, and one landfill. Combustion exhaust for each of these sources is measured from one or more representative sectors including electricity generation, motor vehicles, and household use. Results show that UFP emissions are similar when using biomethane and natural gas with similar sulfur and siloxane content. Approximately 70% of UFPs emitted from water heaters and cooking stoves were semivolatile, but 30% of the UFPs were nonvolatile and did not evaporate even under extremely high dilution conditions. Photochemical aging of biomethane combustion exhaust and natural gas combustion exhaust produced similar amounts of secondary organic aerosol (SOA) formation. The results of the current study suggest that widespread adoption of biogas and biomethane as a substitute for natural gas will not significantly increase ambient concentrations of primary and secondary UFPs if advanced combustion technology is used and the sulfur and siloxane content is similar for biogas/biomethane and natural gas.
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Affiliation(s)
- Jian Xue
- Department of Civil and Environmental Engineering , University of California-Davis , Davis , California 95616 , United States
| | - Yin Li
- Department of Civil and Environmental Engineering , University of California-Davis , Davis , California 95616 , United States
| | - Joshua Peppers
- Department of Civil and Environmental Engineering , University of California-Davis , Davis , California 95616 , United States
| | - Chao Wan
- Atmospheric Science Graduate Group , University of California-Davis , Davis , California 95616 , United States
| | - Norman Y Kado
- Department of Environmental Toxicology , University of California-Davis , Davis , California 95616 , United States
| | - Peter G Green
- Department of Civil and Environmental Engineering , University of California-Davis , Davis , California 95616 , United States
| | - Thomas M Young
- Department of Civil and Environmental Engineering , University of California-Davis , Davis , California 95616 , United States
| | - Michael J Kleeman
- Department of Civil and Environmental Engineering , University of California-Davis , Davis , California 95616 , United States
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26
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Morino Y, Chatani S, Tanabe K, Fujitani Y, Morikawa T, Takahashi K, Sato K, Sugata S. Contributions of Condensable Particulate Matter to Atmospheric Organic Aerosol over Japan. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:8456-8466. [PMID: 29973047 DOI: 10.1021/acs.est.8b01285] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Because emission rates of particulate matter (PM) from stationary combustion sources have been measured without dilution or cooling in Japan, condensable PM has not been included in Japanese emission inventories. In this study, we modified an emission inventory to include condensable PM from stationary combustion sources based on the recent emission surveys using a dilution method. As a result, emission rates of organic aerosol (OA) increased by a factor of 7 over Japan. Stationary combustion sources in the industrial and energy sectors became the largest contributors to OA emissions over Japan in the revised estimates (filterable-plus-condensable PM), while road transport and biomass burning were the dominant OA sources in the previous estimate (filterable PM). These results indicate that condensable PM from large combustion sources makes critical contributions to total PM2.5 emissions. Simulated contributions of condensable PM from combustion sources to atmospheric OA drastically increased around urban and industrial areas, including the Kanto region, where OA concentrations increased by factors of 2.5-6.1. Consideration of condensable PM from stationary combustion sources improved model estimates of OA in winter but caused overestimation of OA concentrations in summer. Contributions of primary and secondary OA should be further evaluated by comparing with organic tracer measurements.
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Affiliation(s)
- Yu Morino
- National Institute for Environmental Studies , 16-2, Onogawa , Tsukuba , Ibaraki 305-8506 , Japan
| | - Satoru Chatani
- National Institute for Environmental Studies , 16-2, Onogawa , Tsukuba , Ibaraki 305-8506 , Japan
| | - Kiyoshi Tanabe
- National Institute for Environmental Studies , 16-2, Onogawa , Tsukuba , Ibaraki 305-8506 , Japan
| | - Yuji Fujitani
- National Institute for Environmental Studies , 16-2, Onogawa , Tsukuba , Ibaraki 305-8506 , Japan
| | - Tazuko Morikawa
- Japan Automobile Research Institute , 2530 Karima , Tsukuba , Ibaraki 305-0822 , Japan
| | - Katsuyuki Takahashi
- Japan Environmental Sanitation Center , 10-6 Yotsuyakami-Cho , Kawasaki , Kanagawa 210-0828 , Japan
| | - Kei Sato
- National Institute for Environmental Studies , 16-2, Onogawa , Tsukuba , Ibaraki 305-8506 , Japan
| | - Seiji Sugata
- National Institute for Environmental Studies , 16-2, Onogawa , Tsukuba , Ibaraki 305-8506 , Japan
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McDonald BC, de Gouw JA, Gilman JB, Jathar SH, Akherati A, Cappa CD, Jimenez JL, Lee-Taylor J, Hayes PL, McKeen SA, Cui YY, Kim SW, Gentner DR, Isaacman-VanWertz G, Goldstein AH, Harley RA, Frost GJ, Roberts JM, Ryerson TB, Trainer M. Volatile chemical products emerging as largest petrochemical source of urban organic emissions. Science 2018; 359:760-764. [PMID: 29449485 DOI: 10.1126/science.aaq0524] [Citation(s) in RCA: 329] [Impact Index Per Article: 54.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/22/2017] [Indexed: 11/02/2022]
Abstract
A gap in emission inventories of urban volatile organic compound (VOC) sources, which contribute to regional ozone and aerosol burdens, has increased as transportation emissions in the United States and Europe have declined rapidly. A detailed mass balance demonstrates that the use of volatile chemical products (VCPs)-including pesticides, coatings, printing inks, adhesives, cleaning agents, and personal care products-now constitutes half of fossil fuel VOC emissions in industrialized cities. The high fraction of VCP emissions is consistent with observed urban outdoor and indoor air measurements. We show that human exposure to carbonaceous aerosols of fossil origin is transitioning away from transportation-related sources and toward VCPs. Existing U.S. regulations on VCPs emphasize mitigating ozone and air toxics, but they currently exempt many chemicals that lead to secondary organic aerosols.
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Affiliation(s)
- Brian C McDonald
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA. .,Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Joost A de Gouw
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Jessica B Gilman
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Shantanu H Jathar
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Ali Akherati
- Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, USA
| | - Christopher D Cappa
- Department of Civil and Environmental Engineering, University of California, Davis, CA, USA
| | - Jose L Jimenez
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO, USA
| | - Julia Lee-Taylor
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,National Center for Atmospheric Research, Boulder, CO, USA
| | - Patrick L Hayes
- Department of Chemistry, Université de Montréal, Montréal, Quebec, Canada
| | - Stuart A McKeen
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Yu Yan Cui
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Si-Wan Kim
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA.,Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Drew R Gentner
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA.,School of Forestry and Environmental Studies, Yale University, New Haven, CT, USA
| | - Gabriel Isaacman-VanWertz
- Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Allen H Goldstein
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, USA.,Department of Civil and Environmental Engineering, University of California, Berkeley, CA, USA
| | - Robert A Harley
- Department of Civil and Environmental Engineering, University of California, Berkeley, CA, USA
| | - Gregory J Frost
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - James M Roberts
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Thomas B Ryerson
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
| | - Michael Trainer
- Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA
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28
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Li HZ, Dallmann TR, Li X, Gu P, Presto AA. Urban Organic Aerosol Exposure: Spatial Variations in Composition and Source Impacts. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:415-426. [PMID: 29227637 DOI: 10.1021/acs.est.7b03674] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We conducted a mobile sampling campaign in a historically industrialized terrain (Pittsburgh, PA) targeting spatial heterogeneity of organic aerosol. Thirty-six sampling sites were chosen based on stratification of traffic, industrial source density, and elevation. We collected organic carbon (OC) on quartz filters, quantified different OC components with thermal-optical analysis, and grouped them based on volatility in decreasing order (OC1, OC2, OC3, OC4, and pyrolyzed carbon (PC)). We compared our ambient OC concentrations (both gas and particle phase) to similar measurements from vehicle dynamometer tests, cooking emissions, biomass burning emissions, and a highway traffic tunnel. OC2 and OC3 loading on ambient filters showed a strong correlation with primary emissions while OC4 and PC were more spatially homogeneous. While we tested our hypothesis of OC2 and OC3 as markers of fresh source exposure for Pittsburgh, the relationship seemed to hold at a national level. Land use regression (LUR) models were developed for the OC fractions, and models had an average R2 of 0.64 (SD = 0.09). The paper demonstrates that OC2 and OC3 can be useful markers for fresh emissions, OC4 is a secondary OC indicator, and PC represents both biomass burning and secondary aerosol. People with higher OC exposure are likely inhaling more fresh OC2 and OC3, since secondary OC4 and PC varies much less drastically in space or with local primary sources.
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Affiliation(s)
- Hugh Z Li
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Timothy R Dallmann
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Xiang Li
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Peishi Gu
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Albert A Presto
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
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Hays MD, Preston W, George BJ, George IJ, Snow R, Faircloth J, Long T, Baldauf RW, McDonald J. Temperature and Driving Cycle Significantly Affect Carbonaceous Gas and Particle Matter Emissions from Diesel Trucks. ENERGY & FUELS : AN AMERICAN CHEMICAL SOCIETY JOURNAL 2017; 31:10.1021/acs.energyfuels.7b01446. [PMID: 32461712 PMCID: PMC7252512 DOI: 10.1021/acs.energyfuels.7b01446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The present study examines the effects of fuel [an ultralow sulfur diesel (ULSD) versus a 20% v/v soy-based biodiesel-80% v/v petroleum blend (B20)], temperature, load, vehicle, driving cycle, and active regeneration technology on gas- and particle-phase carbon emissions from light and medium heavy-duty diesel vehicles (L/MHDDV). The study is performed using chassis dynamometer facilities that support low-temperature operation (-6.7 °C versus 21.7 °C) and heavy loads up to 12 000 kg. Organic and elemental carbon (OC-EC) composition of aerosol particles is determined using a thermal-optical technique. Gas- and particle-phase semivolatile organic compound (SVOC) emissions collected using traditional filter and polyurethane foam sampling media are analyzed using advanced gas chromatograpy/mass spectrometry methods. Study-wide OC and EC emissions are 0.735 and 0.733 mg/km, on average. The emissions factors for diesel vehicles vary widely, and use of a catalyzed diesel particle filter (CDPF) device generally mutes the carbon particle emissions in the exhaust, which contains ~90% w/w gas-phase matter. Interestingly, replacing ULSD with B20 did not significantly influence SVOC emissions, for which sums range from 0.030 to 9.4 mg/km for the L/MHDDVs. However, both low temperature and vehicle cold-starts significantly increase SVOCs in the exhaust. Real-time particle measurements indicate vehicle regeneration technology did influence emissions, although regeneration effects went unresolved using bulk chemistry techniques. A multistudy comparison of the toxic particle-phase polycyclic aromatic hydrocarbons (PAHs; molecular weight (MW) ≥ 252 amu) in diesel exhaust indicates emission factors that span up to 8 orders of magnitude over the past several decades. This study observes conditions under which PAH compounds with MW ≥ 252 amu appear in diesel particles downstream of the CDPF and can even reach low-end concentrations reported earlier for much larger HDDVs with poorly controlled exhaust streams. This rare observation suggests that analysis of PAHs in particles emitted from modern L/MHDDVs may be more complex than recognized previously.
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Affiliation(s)
- Michael D Hays
- Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - William Preston
- Consolidated Safety Services Inc., 1910 Sedwick Road, Durham, North Carolina 27713, United States
| | - Barbara J George
- Office of Research and Development, National Health and Environmental Effects Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Ingrid J George
- Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Richard Snow
- Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - James Faircloth
- Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Thomas Long
- Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Richard W Baldauf
- Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
| | - Joseph McDonald
- Office of Research and Development, National Risk Management Research Laboratory, United States Environmental Protection Agency, Research Triangle Park, North Carolina 27711, United States
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30
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Characterizing particulate polycyclic aromatic hydrocarbon emissions from diesel vehicles using a portable emissions measurement system. Sci Rep 2017; 7:10058. [PMID: 28855647 PMCID: PMC5577249 DOI: 10.1038/s41598-017-09822-w] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 07/31/2017] [Indexed: 11/30/2022] Open
Abstract
Particulate polycyclic aromatic hydrocarbons (p-PAHs) emitted from diesel vehicles are of concern because of their significant health impacts. Laboratory tests, road tunnel and roadside experiments have been conducted to measure p-PAH emissions. While providing valuable information, these methods have limited capabilities of characterizing p-PAH emissions either from individual vehicles or under real-world conditions. We employed a portable emissions measurement (PEMS) to measure real-world emission factors of priority p-PAHs for diesel vehicles representative of an array of emission control technologies. The results indicated over 80% reduction in p-PAH emission factors comparing the China V and China II emission standard groups (113 μg kg−1 vs. 733 μg kg−1). The toxicity abatement in terms of Benzo[a]pyrene equivalent emissions was substantial because of the large reductions in highly toxic components. By assessing real traffic conditions, the p-PAH emission factors on freeways were lower than on local roads by 52% ± 24%. A significant correlation (R2~0.85) between the p-PAH and black carbon emissions was identified with a mass ratio of approximately 1/2000. A literature review indicated that diesel p-PAH emission factors varied widely by engine technology, measurement methods and conditions, and the molecular diagnostic ratio method for source apportionment should be used with great caution.
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Martin N, Lombard M, Jensen KR, Kelley P, Pratt T, Traviss N. Effect of biodiesel fuel on "real-world", nonroad heavy duty diesel engine particulate matter emissions, composition and cytotoxicity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 586:409-418. [PMID: 28236480 PMCID: PMC7372720 DOI: 10.1016/j.scitotenv.2016.12.041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 11/23/2016] [Accepted: 12/05/2016] [Indexed: 05/15/2023]
Abstract
Biodiesel is regarded by many as a "greener" alternative fuel to petroleum diesel with potentially lower health risk. However, recent studies examining biodiesel particulate matter (PM) characteristics and health effects are contradictive, and typically utilize PM generated by passenger car engines in laboratory settings. There is a critical need to analyze diesel and biodiesel PM generated in a "real-world" setting where heavy duty-diesel (HDD) engines and commercially purchased fuel are utilized. This study compares the mass concentrations, chemical composition and cytotoxicity of real-world PM from combustion of both petroleum diesel and a waste grease 20% biodiesel blend (B20) at a community recycling center operating HDD nonroad equipment. PM was analyzed for metals, elemental/organic carbon (EC/OC), polycyclic aromatic hydrocarbons (PAHs), and nitro-polycyclic aromatic hydrocarbons (N-PAHs). Cytotoxicity in a human lung epithelial cell line (BEAS-2B) following 24h exposure to the real-world particles was also evaluated. On average, higher concentrations for both EC and OC were measured in diesel PM. B20 PM contained significantly higher levels of Cu and Mo whereas diesel PM contained significantly higher concentrations of Pb. Principal component analysis determined Mo, Cu, and Ni were the metals with the greatest loading factor, suggesting a unique pattern related to the B20 fuel source. Total PAH concentration during diesel fuel use was 1.9 times higher than during B20 operations; however, total N-PAH concentration was 3.3 times higher during B20 use. Diesel PM cytotoxicity was 8.5 times higher than B20 PM (p<0.05) in a BEAS-2B cell line. This study contributes novel data on real-world, nonroad engine sources of metals, PAH and N-PAH species, comparing tailpipe PM vs. PM collected inside the equipment cabin. Results suggest PM generated from burning petroleum diesel in nonroad engines may be more harmful to human health, but the links between exposure, composition and toxicity are not straightforward.
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Affiliation(s)
- Nathan Martin
- Department of Environmental Studies, Keene State College, Keene, NH, 03431, United States
| | - Melissa Lombard
- Department of Earth Sciences, University of New Hampshire, Durham, NH 03824, United States
| | - Kirk R Jensen
- Department of Chemistry and Geochemistry, Colorado School of Mines, Golden, CO, 80401, United States
| | - Patrick Kelley
- Department of Environmental Studies, Keene State College, Keene, NH, 03431, United States
| | - Tara Pratt
- Department of Environmental Studies, Keene State College, Keene, NH, 03431, United States
| | - Nora Traviss
- Department of Environmental Studies, Keene State College, Keene, NH, 03431, United States.
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Habib G. Chemical and optical properties of PM 2.5 from on-road operation of light duty vehicles in Delhi city. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 586:900-916. [PMID: 28238373 DOI: 10.1016/j.scitotenv.2017.02.070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Revised: 01/26/2017] [Accepted: 02/08/2017] [Indexed: 06/06/2023]
Abstract
This study reports emission factors of PM2.5, elemental carbon (EC), organic carbon (OC), ions, trace elements and mass absorption cross-sections (MAC) of aerosol emitted from the on-road operation of light duty vehicles of different vintages. A portable dilution system was used to achieve complete quenching of aerosol at near ambient condition. The particles were collected on the filters and analyzed for chemical and light absorbing properties of aerosol. The diesel-powered passenger cars emitted higher PM2.5 (56-356mgkm-1) with a large fraction of EC (37-65%), while emissions from gasoline (46-78mgkm-1), and CNG vehicles (33-34mgkm-1) were low and contained low EC (5-15%) and remarkably high OC (46-91%). The MAC of aerosols for diesel vehicles (32-208m2g-1 of PM2.5) were well explained by EC content (31-62%) and showed similarity with MAC values reported for wood fuel combustion in cooking stoves indicating the two sources cannot be resolved on the basis of light absorption properties in source apportionment studies. Ionic contributions to PM2.5 were highest for 4W-gasoline (11-19%) compared to 4W-diesel (7-11%), and CNG (9-10%). The abundance of ions such as Na+, Ca2+, SO42-, NO3-, and NH4+ could be due to use of lubricant oil and abrasive nature of engine of old vehicles. Trace elements (Al, Fe, Zn, Pb, and Cu) emitted from after-treatment devices, additives in lube oil, and wearing of engine components, were found to be 2-14%, 3-8% and 11-12% of total PM2.5 for 4W of diesel, gasoline, and CNG respectively. This study indicates that aerosol emissions from on-road vehicles show a strong dependency on vehicle maintenance, engine type and after-treatment techniques.
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Jathar SH, Woody M, Pye HOT, Baker KR, Robinson AL. Chemical transport model simulations of organic aerosol in southern California: model evaluation and gasoline and diesel source contributions. ATMOSPHERIC CHEMISTRY AND PHYSICS 2017; 17:4305-4318. [PMID: 30079083 PMCID: PMC6070158 DOI: 10.5194/acp-17-4305-2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Gasoline- and diesel-fueled engines are ubiquitous sources of air pollution in urban environments. They emit both primary particulate matter and precursor gases that react to form secondary particulate matter in the atmosphere. In this work, we updated the organic aerosol module and organic emissions inventory of a three-dimensional chemical transport model, the Community Multiscale Air Quality Model (CMAQ), using recent, experimentally derived inputs and parameterizations for mobile sources. The updated model included a revised volatile organic compound (VOC) speciation for mobile sources and secondary organic aerosol (SOA) formation from unspeciated intermediate volatility organic compounds (IVOCs). The updated model was used to simulate air quality in southern California during May and June 2010, when the California Research at the Nexus of Air Quality and Climate Change (CalNex) study was conducted. Compared to the Traditional version of CMAQ, which is commonly used for regulatory applications, the updated model did not significantly alter the predicted organic aerosol (OA) mass concentrations but did substantially improve predictions of OA sources and composition (e.g., POA-SOA split), as well as ambient IVOC concentrations. The updated model, despite substantial differences in emissions and chemistry, performed similar to a recently released research version of CMAQ (Woody et al., 2016) that did not include the updated VOC and IVOC emissions and SOA data. Mobile sources were predicted to contribute 30-40 % of the OA in southern California (half of which was SOA), making mobile sources the single largest source contributor to OA in southern California. The remainder of the OA was attributed to non-mobile anthropogenic sources (e.g., cooking, biomass burning) with biogenic sources contributing to less than 5 % to the total OA. Gasoline sources were predicted to contribute about 13 times more OA than diesel sources; this difference was driven by differences in SOA production. Model predictions highlighted the need to better constrain multi-generational oxidation reactions in chemical transport models.
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Affiliation(s)
- Shantanu H. Jathar
- Mechanical Engineering, Colorado State University, Fort Collins, CO 80525, USA
| | - Matthew Woody
- US Environmental Protection Agency, Research Triangle Park, NC 27711, USA
| | - Havala O. T. Pye
- US Environmental Protection Agency, Research Triangle Park, NC 27711, USA
| | - Kirk R. Baker
- US Environmental Protection Agency, Research Triangle Park, NC 27711, USA
| | - Allen L. Robinson
- Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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Murphy BN, Woody MC, Jimenez JL, Carlton AMG, Hayes PL, Liu S, Ng NL, Russell LM, Setyan A, Xu L, Young J, Zaveri RA, Zhang Q, Pye HOT. Semivolatile POA and parameterized total combustion SOA in CMAQv5.2: impacts on source strength and partitioning. ATMOSPHERIC CHEMISTRY AND PHYSICS 2017; 17:11107-11133. [PMID: 32038726 PMCID: PMC7006837 DOI: 10.5194/acp-17-11107-2017] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Mounting evidence from field and laboratory observations coupled with atmospheric model analyses shows that primary combustion emissions of organic compounds dynamically partition between the vapor and particulate phases, especially as near-source emissions dilute and cool to ambient conditions. The most recent version of the Community Multiscale Air Quality model version 5.2 (CMAQv5.2) accounts for the semivolatile partitioning and gas-phase aging of these primary organic aerosol (POA) compounds consistent with experimentally derived parameterizations. We also include a new surrogate species, potential secondary organic aerosol from combustion emissions (pcSOA), which provides a representation of the secondary organic aerosol (SOA) from anthropogenic combustion sources that could be missing from current chemical transport model predictions. The reasons for this missing mass likely include the following: (1) unspeciated semivolatile and intermediate volatility organic compound (SVOC and IVOC, respectively) emissions missing from current inventories, (2) multigenerational aging of organic vapor products from known SOA precursors (e.g., toluene, alkanes), (3) underestimation of SOA yields due to vapor wall losses in smog chamber experiments, and (4) reversible organic compounds-water interactions and/or aqueous-phase processing of known organic vapor emissions. CMAQ predicts the spatially averaged contribution of pcSOA to OA surface concentrations in the continental United States to be 38.6 and 23.6 % in the 2011 winter and summer, respectively. Whereas many past modeling studies focused on a particular measurement campaign, season, location, or model configuration, we endeavor to evaluate the model and important uncertain parameters with a comprehensive set of United States-based model runs using multiple horizontal scales (4 and 12 km), gas-phase chemical mechanisms, and seasons and years. The model with representation of semivolatile POA improves predictions of hourly OA observations over the traditional nonvolatile model at sites during field campaigns in southern California (CalNex, May-June 2010), northern California (CARES, June 2010), the southeast US (SOAS, June 2013; SEARCH, January and July, 2011). Model improvements manifest better correlations (e.g., the correlation coefficient at Pasadena at night increases from 0.38 to 0.62) and reductions in underprediction during the photochemically active afternoon period (e.g., bias at Pasadena from -5.62 to -2.42 μg m-3). Daily averaged predictions of observations at routine-monitoring networks from simulations over the continental US (CONUS) in 2011 show modest improvement during winter, with mean biases reducing from 1.14 to 0.73μg m-3, but less change in the summer when the decreases from POA evaporation were similar to the magnitude of added SOA mass. Because the model-performance improvement realized by including the relatively simple pcSOA approach is similar to that of more-complicated parameterizations of OA formation and aging, we recommend caution when applying these more-complicated approaches as they currently rely on numerous uncertain parameters. The pcSOA parameters optimized for performance at the southern and northern California sites lead to higher OA formation than is observed in the CONUS evaluation. This may be due to any of the following: variations in real pcSOA in different regions or time periods, too-high concentrations of other OA sources in the model that are important over the larger domain, or other model issues such as loss processes. This discrepancy is likely regionally and temporally dependent and driven by interferences from factors like varying emissions and chemical regimes.
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Affiliation(s)
- Benjamin N. Murphy
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Matthew C. Woody
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Jose L. Jimenez
- Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO, USA
| | - Ann Marie G. Carlton
- Department of Chemistry, University of California, Irvine, Irvine, CA 92697, USA
| | - Patrick L. Hayes
- Department of Chemistry, Université de Montréal, Montréal, QC, Canada
| | - Shang Liu
- School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Nga L. Ng
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Lynn M. Russell
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
| | - Ari Setyan
- EMPA, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Lu Xu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Jeff Young
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Rahul A. Zaveri
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Qi Zhang
- Department of Environmental Toxicology, University of California, Davis, Davis, CA, USA
| | - Havala O. T. Pye
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
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35
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Murphy BN, Woody MC, Jimenez JL, Carlton AMG, Hayes PL, Liu S, Ng NL, Russell LM, Setyan A, Xu L, Young J, Zaveri RA, Zhang Q, Pye HOT. Semivolatile POA and parameterized total combustion SOA in CMAQv5.2: impacts on source strength and partitioning. ATMOSPHERIC CHEMISTRY AND PHYSICS 2017. [PMID: 32038726 DOI: 10.5194/acp-2017-193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Mounting evidence from field and laboratory observations coupled with atmospheric model analyses shows that primary combustion emissions of organic compounds dynamically partition between the vapor and particulate phases, especially as near-source emissions dilute and cool to ambient conditions. The most recent version of the Community Multiscale Air Quality model version 5.2 (CMAQv5.2) accounts for the semivolatile partitioning and gas-phase aging of these primary organic aerosol (POA) compounds consistent with experimentally derived parameterizations. We also include a new surrogate species, potential secondary organic aerosol from combustion emissions (pcSOA), which provides a representation of the secondary organic aerosol (SOA) from anthropogenic combustion sources that could be missing from current chemical transport model predictions. The reasons for this missing mass likely include the following: (1) unspeciated semivolatile and intermediate volatility organic compound (SVOC and IVOC, respectively) emissions missing from current inventories, (2) multigenerational aging of organic vapor products from known SOA precursors (e.g., toluene, alkanes), (3) underestimation of SOA yields due to vapor wall losses in smog chamber experiments, and (4) reversible organic compounds-water interactions and/or aqueous-phase processing of known organic vapor emissions. CMAQ predicts the spatially averaged contribution of pcSOA to OA surface concentrations in the continental United States to be 38.6 and 23.6 % in the 2011 winter and summer, respectively. Whereas many past modeling studies focused on a particular measurement campaign, season, location, or model configuration, we endeavor to evaluate the model and important uncertain parameters with a comprehensive set of United States-based model runs using multiple horizontal scales (4 and 12 km), gas-phase chemical mechanisms, and seasons and years. The model with representation of semivolatile POA improves predictions of hourly OA observations over the traditional nonvolatile model at sites during field campaigns in southern California (CalNex, May-June 2010), northern California (CARES, June 2010), the southeast US (SOAS, June 2013; SEARCH, January and July, 2011). Model improvements manifest better correlations (e.g., the correlation coefficient at Pasadena at night increases from 0.38 to 0.62) and reductions in underprediction during the photochemically active afternoon period (e.g., bias at Pasadena from -5.62 to -2.42 μg m-3). Daily averaged predictions of observations at routine-monitoring networks from simulations over the continental US (CONUS) in 2011 show modest improvement during winter, with mean biases reducing from 1.14 to 0.73μg m-3, but less change in the summer when the decreases from POA evaporation were similar to the magnitude of added SOA mass. Because the model-performance improvement realized by including the relatively simple pcSOA approach is similar to that of more-complicated parameterizations of OA formation and aging, we recommend caution when applying these more-complicated approaches as they currently rely on numerous uncertain parameters. The pcSOA parameters optimized for performance at the southern and northern California sites lead to higher OA formation than is observed in the CONUS evaluation. This may be due to any of the following: variations in real pcSOA in different regions or time periods, too-high concentrations of other OA sources in the model that are important over the larger domain, or other model issues such as loss processes. This discrepancy is likely regionally and temporally dependent and driven by interferences from factors like varying emissions and chemical regimes.
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Affiliation(s)
- Benjamin N Murphy
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Matthew C Woody
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Jose L Jimenez
- Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder, Boulder, CO, USA
- Department of Chemistry and Biochemistry, University of Colorado Boulder, Boulder, CO, USA
| | - Ann Marie G Carlton
- Department of Chemistry, University of California, Irvine, Irvine, CA 92697, USA
| | - Patrick L Hayes
- Department of Chemistry, Université de Montréal, Montréal, QC, Canada
| | - Shang Liu
- School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui, China
| | - Nga L Ng
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA
| | - Lynn M Russell
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, USA
| | - Ari Setyan
- EMPA, Swiss Federal Laboratories for Materials Science and Technology, 8600 Dübendorf, Switzerland
| | - Lu Xu
- School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Jeff Young
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
| | - Rahul A Zaveri
- Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, USA
| | - Qi Zhang
- Department of Environmental Toxicology, University of California, Davis, Davis, CA, USA
| | - Havala O T Pye
- National Exposure Research Laboratory, US Environmental Protection Agency, Research Triangle Park, NC, USA
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36
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Li X, Dallmann TR, May AA, Tkacik DS, Lambe AT, Jayne JT, Croteau PL, Presto AA. Gas-Particle Partitioning of Vehicle Emitted Primary Organic Aerosol Measured in a Traffic Tunnel. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:12146-12155. [PMID: 27762132 DOI: 10.1021/acs.est.6b01666] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We measured the gas-particle partitioning of vehicle emitted primary organic aerosol (POA) in a traffic tunnel with three independent methods: artifact corrected bare-quartz filters, thermodenuder (TD) measurements, and thermal-desorption gas-chromatography mass-spectrometry (TD-GC-MS). Results from all methods consistently show that vehicle emitted POA measured in the traffic tunnel is semivolatile under a wide range of fleet compositions and ambient conditions. We compared the gas-particle partitioning of POA measured in both tunnel and dynamometer studies and found that volatility distributions measured in the traffic tunnel are similar to volatility distributions measured in the dynamometer studies, and predict similar gas-particle partitioning in the TD. These results suggest that the POA volatility distribution measured in the dynamometer studies can be applied to describe gas-particle partitioning of ambient POA emissions. The POA volatility distribution measured in the tunnel does not have significant diurnal or seasonal variations, which indicate that a single volatility distribution is adequate to describe the gas-particle partitioning of vehicle emitted POA in the urban environment.
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Affiliation(s)
- Xiang Li
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Timothy R Dallmann
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Andrew A May
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Daniel S Tkacik
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
- Department of Civil and Environmental Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Andrew T Lambe
- Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
| | - John T Jayne
- Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
| | - Philip L Croteau
- Aerodyne Research, Inc., Billerica, Massachusetts 01821, United States
| | - Albert A Presto
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
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37
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Zhao B, Wang S, Donahue NM, Jathar SH, Huang X, Wu W, Hao J, Robinson AL. Quantifying the effect of organic aerosol aging and intermediate-volatility emissions on regional-scale aerosol pollution in China. Sci Rep 2016; 6:28815. [PMID: 27350423 PMCID: PMC4923863 DOI: 10.1038/srep28815] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 06/08/2016] [Indexed: 12/03/2022] Open
Abstract
Secondary organic aerosol (SOA) is one of the least understood constituents of fine particles; current widely-used models cannot predict its loadings or oxidation state. Recent laboratory experiments demonstrated the importance of several new processes, including aging of SOA from traditional precursors, aging of primary organic aerosol (POA), and photo-oxidation of intermediate volatility organic compounds (IVOCs). However, evaluating the effect of these processes in the real atmosphere is challenging. Most models used in previous studies are over-simplified and some key reaction trajectories are not captured, and model parameters are usually phenomenological and lack experimental constraints. Here we comprehensively assess the effect of organic aerosol (OA) aging and intermediate-volatility emissions on regional-scale OA pollution with a state-of-the-art model framework and experimentally constrained parameters. We find that OA aging and intermediate-volatility emissions together increase OA and SOA concentrations in Eastern China by about 40% and a factor of 10, respectively, thereby improving model-measurement agreement significantly. POA and IVOCs both constitute over 40% of OA concentrations, and IVOCs constitute over half of SOA concentrations; this differs significantly from previous apportionment of SOA sources. This study facilitates an improved estimate of aerosol-induced climate and health impacts, and implies a shift from current fine-particle control policies.
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Affiliation(s)
- Bin Zhao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Shuxiao Wang
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.,State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Neil M Donahue
- Center for Atmospheric Particle Studies, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA
| | - Shantanu H Jathar
- Civil and Environmental Engineering, University of California, Davis, CA 95616, USA
| | - Xiaofeng Huang
- Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Wenjing Wu
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
| | - Jiming Hao
- State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.,State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
| | - Allen L Robinson
- Center for Atmospheric Particle Studies, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, PA 15213, USA
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Zhao Y, Nguyen NT, Presto AA, Hennigan CJ, May AA, Robinson AL. Intermediate Volatility Organic Compound Emissions from On-Road Gasoline Vehicles and Small Off-Road Gasoline Engines. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:4554-63. [PMID: 27023443 DOI: 10.1021/acs.est.5b06247] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Dynamometer experiments were conducted to characterize the intermediate volatility organic compound (IVOC) emissions from a fleet of on-road gasoline vehicles and small off-road gasoline engines. IVOCs were quantified through gas chromatography/mass spectrometry analysis of adsorbent samples collected from a constant volume sampler. The dominant fraction (>80%, on average) of IVOCs could not be resolved on a molecular level. These unspeciated IVOCs were quantified as two chemical classes (unspeciated branched alkanes and cyclic compounds) in 11 retention-time-based bins. IVOC emission factors (mg kg-fuel(-1)) from on-road vehicles varied widely from vehicle to vehicle, but showed a general trend of lower emissions for newer vehicles that met more stringent emission standards. IVOC emission factors for 2-stroke off-road engines were substantially higher than 4-stroke off-road engines and on-road vehicles. Despite large variations in the magnitude of emissions, the IVOC volatility distribution and chemical characteristics were consistent across all tests and IVOC emissions were strongly correlated with nonmethane hydrocarbons (NMHCs), primary organic aerosol and speciated IVOCs. Although IVOC emissions only correspond to approximately 4% of NMHC emissions from on-road vehicles over the cold-start unified cycle, they are estimated to produce as much or more SOA than single-ring aromatics. Our results clearly demonstrate that IVOCs from gasoline engines are an important class of SOA precursors and provide observational constraints on IVOC emission factors and chemical composition to facilitate their inclusion into atmospheric chemistry models.
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Affiliation(s)
- Yunliang Zhao
- Center for Atmospheric Particle Studies, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Ngoc T Nguyen
- Center for Atmospheric Particle Studies, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Albert A Presto
- Center for Atmospheric Particle Studies, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Christopher J Hennigan
- Center for Atmospheric Particle Studies, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Andrew A May
- Center for Atmospheric Particle Studies, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Allen L Robinson
- Center for Atmospheric Particle Studies, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
- Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
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Ye P, Ding X, Ye Q, Robinson ES, Donahue NM. Uptake of Semivolatile Secondary Organic Aerosol Formed from α-Pinene into Nonvolatile Polyethylene Glycol Probe Particles. J Phys Chem A 2016; 120:1459-67. [DOI: 10.1021/acs.jpca.5b07435] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Penglin Ye
- Center
for Atmospheric Particle Studies, Carnegie Mellon University, 5000
Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Xiang Ding
- Center
for Atmospheric Particle Studies, Carnegie Mellon University, 5000
Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
- State
Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Qing Ye
- Center
for Atmospheric Particle Studies, Carnegie Mellon University, 5000
Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Ellis S. Robinson
- Center
for Atmospheric Particle Studies, Carnegie Mellon University, 5000
Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Neil M. Donahue
- Center
for Atmospheric Particle Studies, Carnegie Mellon University, 5000
Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
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Zhao Y, Nguyen NT, Presto AA, Hennigan CJ, May AA, Robinson AL. Intermediate Volatility Organic Compound Emissions from On-Road Diesel Vehicles: Chemical Composition, Emission Factors, and Estimated Secondary Organic Aerosol Production. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:11516-11526. [PMID: 26322746 DOI: 10.1021/acs.est.5b02841] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Emissions of intermediate-volatility organic compounds (IVOCs) from five on-road diesel vehicles and one off-road diesel engine were characterized during dynamometer testing. The testing evaluated the effects of driving cycles, fuel composition and exhaust aftertreatment devices. On average, more than 90% of the IVOC emissions were not identified on a molecular basis, instead appearing as an unresolved complex mixture (UCM) during gas-chromatography mass-spectrometry analysis. Fuel-based emissions factors (EFs) of total IVOCs (speciated + unspeciated) depend strongly on aftertreatment technology and driving cycle. Total-IVOC emissions from vehicles equipped with catalyzed diesel particulate filters (DPF) are substantially lower (factor of 7 to 28, depending on driving cycle) than from vehicles without any exhaust aftertreatment. Total-IVOC emissions from creep and idle operations are substantially higher than emissions from high-speed operations. Although the magnitude of the total-IVOC emissions can vary widely, there is little variation in the IVOC composition across the set of tests. The new emissions data are combined with published yield data to investigate secondary organic aerosol (SOA) formation. SOA production from unspeciated IVOCs is estimated using surrogate compounds, which are assigned based on gas-chromatograph retention time and mass spectral signature of the IVOC UCM. IVOCs contribute the vast majority of the SOA formed from exhaust from on-road diesel vehicles. The estimated SOA production is greater than predictions by previous studies and substantially higher than primary organic aerosol. Catalyzed DPFs substantially reduce SOA formation potential of diesel exhaust, except at low speed operations.
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Affiliation(s)
- Yunliang Zhao
- Center for Atmospheric Particle Studies and ‡Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Ngoc T Nguyen
- Center for Atmospheric Particle Studies and ‡Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Albert A Presto
- Center for Atmospheric Particle Studies and ‡Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Christopher J Hennigan
- Center for Atmospheric Particle Studies and ‡Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Andrew A May
- Center for Atmospheric Particle Studies and ‡Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
| | - Allen L Robinson
- Center for Atmospheric Particle Studies and ‡Department of Mechanical Engineering, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States
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Zhang R, Wang G, Guo S, Zamora ML, Ying Q, Lin Y, Wang W, Hu M, Wang Y. Formation of urban fine particulate matter. Chem Rev 2015; 115:3803-55. [PMID: 25942499 DOI: 10.1021/acs.chemrev.5b00067] [Citation(s) in RCA: 471] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Renyi Zhang
- §State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China
| | | | - Song Guo
- §State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China
| | | | | | | | | | - Min Hu
- §State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China
| | - Yuan Wang
- #Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91125, United States
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McDonald BC, Goldstein AH, Harley RA. Long-term trends in California mobile source emissions and ambient concentrations of black carbon and organic aerosol. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:5178-88. [PMID: 25793355 DOI: 10.1021/es505912b] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A fuel-based approach is used to assess long-term trends (1970-2010) in mobile source emissions of black carbon (BC) and organic aerosol (OA, including both primary emissions and secondary formation). The main focus of this analysis is the Los Angeles Basin, where a long record of measurements is available to infer trends in ambient concentrations of BC and organic carbon (OC), with OC used here as a proxy for OA. Mobile source emissions and ambient concentrations have decreased similarly, reflecting the importance of on- and off-road engines as sources of BC and OA in urban areas. In 1970, the on-road sector accounted for ∼90% of total mobile source emissions of BC and OA (primary + secondary). Over time, as on-road engine emissions have been controlled, the relative importance of off-road sources has grown. By 2010, off-road engines were estimated to account for 37 ± 20% and 45 ± 16% of total mobile source contributions to BC and OA, respectively, in the Los Angeles area. This study highlights both the success of efforts to control on-road emission sources, and the importance of considering off-road engine and other VOC source contributions when assessing long-term emission and ambient air quality trends.
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Unspeciated organic emissions from combustion sources and their influence on the secondary organic aerosol budget in the United States. Proc Natl Acad Sci U S A 2014; 111:10473-8. [PMID: 25002466 DOI: 10.1073/pnas.1323740111] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Secondary organic aerosol (SOA) formed from the atmospheric oxidation of nonmethane organic gases (NMOG) is a major contributor to atmospheric aerosol mass. Emissions and smog chamber experiments were performed to investigate SOA formation from gasoline vehicles, diesel vehicles, and biomass burning. About 10-20% of NMOG emissions from these major combustion sources are not routinely speciated and therefore are currently misclassified in emission inventories and chemical transport models. The smog chamber data demonstrate that this misclassification biases model predictions of SOA production low because the unspeciated NMOG produce more SOA per unit mass than the speciated NMOG. We present new source-specific SOA yield parameterizations for these unspeciated emissions. These parameterizations and associated source profiles are designed for implementation in chemical transport models. Box model calculations using these new parameterizations predict that NMOG emissions from the top six combustion sources form 0.7 Tg y(-1) of first-generation SOA in the United States, almost 90% of which is from biomass burning and gasoline vehicles. About 85% of this SOA comes from unspeciated NMOG, demonstrating that chemical transport models need improved treatment of combustion emissions to accurately predict ambient SOA concentrations.
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Qiu C, Khalizov AF, Hogan B, Petersen EL, Zhang R. High sensitivity of diesel soot morphological and optical properties to combustion temperature in a shock tube. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:6444-6452. [PMID: 24803287 DOI: 10.1021/es405589d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Carbonaceous particles produced from combustion of fossil fuels have strong impacts on air quality and climate, yet quantitative relationships between particle characteristics and combustion conditions remain inadequately understood. We have used a shock tube to study the formation and properties of diesel combustion soot, including particle size distributions, effective density, elemental carbon (EC) mass fraction, mass-mobility scaling exponent, hygroscopicity, and light absorption and scattering. These properties are found to be strongly dependent on the combustion temperature and fuel equivalence ratio. Whereas combustion at higher temperatures (∼2000 K) yields fractal particles of a larger size and high EC content (90 wt %), at lower temperatures (∼1400 K) smaller particles of a higher organic content (up to 65 wt %) are produced. Single scattering albedo of soot particles depends largely on their organic content, increasing drastically from 0.3 to 0.8 when the particle EC mass fraction decreases from 0.9 to 0.3. The mass absorption cross-section of diesel soot increases with combustion temperature, being the highest for particles with a higher EC content. Our results reveal that combustion conditions, especially the temperature, may have significant impacts on the direct and indirect climate forcing of atmospheric soot aerosols.
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Affiliation(s)
- Chong Qiu
- Department of Chemistry & Industrial Hygiene, University of North Alabama , Florence, Alabama 35632-5049, United States
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Worton DR, Isaacman G, Gentner DR, Dallmann TR, Chan AWH, Ruehl C, Kirchstetter TW, Wilson KR, Harley RA, Goldstein AH. Lubricating oil dominates primary organic aerosol emissions from motor vehicles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:3698-3706. [PMID: 24621254 DOI: 10.1021/es405375j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Motor vehicles are major sources of primary organic aerosol (POA), which is a mixture of a large number of organic compounds that have not been comprehensively characterized. In this work, we apply a recently developed gas chromatography mass spectrometry approach utilizing "soft" vacuum ultraviolet photoionization to achieve unprecedented chemical characterization of motor vehicle POA emissions in a roadway tunnel with a mass closure of >60%. The observed POA was characterized by number of carbon atoms (NC), number of double bond equivalents (NDBE) and degree of molecular branching. Vehicular POA was observed to predominantly contain cycloalkanes with one or more rings and one or more branched alkyl side chains (≥80%) with low abundances of n-alkanes and aromatics (<5%), similar to "fresh" lubricating oil. The gas chromatography retention time data indicates that the cycloalkane ring structures are most likely dominated by cyclohexane and cyclopentane rings and not larger cycloalkanes. High molecular weight combustion byproducts, that is, alkenes, oxygenates, and aromatics, were not present in significant amounts. The observed carbon number and chemical composition of motor vehicle POA was consistent with lubricating oil being the dominant source from both gasoline and diesel-powered vehicles, with an additional smaller contribution from unburned diesel fuel and a negligible contribution from unburned gasoline.
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Affiliation(s)
- David R Worton
- Department of Environmental Science, Policy and Management, University of California , Berkeley, California 94720, United States
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Gordon TD, Tkacik DS, Presto AA, Zhang M, Jathar SH, Nguyen NT, Massetti J, Truong T, Cicero-Fernandez P, Maddox C, Rieger P, Chattopadhyay S, Maldonado H, Maricq MM, Robinson AL. Primary gas- and particle-phase emissions and secondary organic aerosol production from gasoline and diesel off-road engines. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:14137-46. [PMID: 24261886 DOI: 10.1021/es403556e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Dilution and smog chamber experiments were performed to characterize the primary emissions and secondary organic aerosol (SOA) formation from gasoline and diesel small off-road engines (SOREs). These engines are high emitters of primary gas- and particle-phase pollutants relative to their fuel consumption. Two- and 4-stroke gasoline SOREs emit much more (up to 3 orders of magnitude more) nonmethane organic gases (NMOGs), primary PM and organic carbon than newer on-road gasoline vehicles (per kg of fuel burned). The primary emissions from a diesel transportation refrigeration unit were similar to those of older, uncontrolled diesel engines used in on-road vehicles (e.g., premodel year 2007 heavy-duty diesel trucks). Two-strokes emitted the largest fractional (and absolute) amount of SOA precursors compared to diesel and 4-stroke gasoline SOREs; however, 35-80% of the NMOG emissions from the engines could not be speciated using traditional gas chromatography or high-performance liquid chromatography. After 3 h of photo-oxidation in a smog chamber, dilute emissions from both 2- and 4-stroke gasoline SOREs produced large amounts of semivolatile SOA. The effective SOA yield (defined as the ratio of SOA mass to estimated mass of reacted precursors) was 2-4% for 2- and 4-stroke SOREs, which is comparable to yields from dilute exhaust from older passenger cars and unburned gasoline. This suggests that much of the SOA production was due to unburned fuel and/or lubrication oil. The total PM contribution of different mobile source categories to the ambient PM burden was calculated by combining primary emission, SOA production and fuel consumption data. Relative to their fuel consumption, SOREs are disproportionately high total PM sources; however, the vastly greater fuel consumption of on-road vehicles renders them (on-road vehicles) the dominant mobile source of ambient PM in the Los Angeles area.
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Affiliation(s)
- Timothy D Gordon
- Center for Atmospheric Particle Studies, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
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