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Zhang W, Xing Y, Su W, Wang J, Jia H, Cui Y, Chen J, Zhang H. Degradation of o-dichlorobenzene by DBD-NTP co-modified titanium gel catalyst. J Environ Sci (China) 2024; 143:71-84. [PMID: 38644025 DOI: 10.1016/j.jes.2023.07.035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 04/23/2024]
Abstract
In order to study the degradation process of dioxins in industrial flue gas, the decomposition of o-dichlorobenzene (o-DCB) in a DBD plasma catalytic reactor was investigated. The results showed that an NTP-catalyzed system, especially using the CuMnTiOx catalyst, had better o-DCB degradation performance compared to plasma alone. The combination of the CuMnTiOx catalyst with NTP can achieve a degradation efficiency of up to 97.2% for o-DCB; the selectivity of CO and CO2 and the carbon balance were 40%, 45%, and 85%, respectively. The dielectric constant and electrical property results indicated that the surface discharge capacity of the catalysts played a major role in the degradation of o-DCB, and a higher dielectric constant could suppress the plasma expansion and enhance the duration of the plasma discharge per discharge cycle. According to the O1s XPS and O2-TPD results, the conversion of CO to CO2 follows the M-v-K mechanism; thus, the active species on the catalyst surface play an important role. Moreover, the CuMnTiOx and NTP mixed system exhibited excellent stability, which is probably because Cu doping improved the lifetime of the catalyst. This work can provide an experimental and theoretical basis for research in the degradation of o-DCB by plasma catalyst systems.
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Affiliation(s)
- Wenbo Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Yi Xing
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing 100083, China
| | - Wei Su
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China; Guangdong Province Engineering Laboratory for Air Pollution Control, Guangzhou 510530, China.
| | - Jiaqing Wang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Haoqi Jia
- College of Environmental and Resource Sciences, Shanxi University, Taiyuan 030006, China
| | - Yongkang Cui
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Jing Chen
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Hui Zhang
- Sinosteel Maanshan Mine Research Institute Co. Ltd., Anhui 243071, China
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Yang H, Chen A, Wang F, Lan T, Zhang J, Hu X, Shen Y, Cheng D, Zhang D. Phosphotungstic Acid as a Dechlorination Agent Collaborates with CeO 2 for Synergistic Catalytic Elimination of NO x and Chlorobenzene. Environ Sci Technol 2024; 58:7672-7682. [PMID: 38639327 DOI: 10.1021/acs.est.4c02246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
The development of efficient technologies for the synergistic catalytic elimination of NOx and chlorinated volatile organic compounds (CVOCs) remains challenging. Chlorine species from CVOCs are prone to catalyst poisoning, which increases the degradation temperature of CVOCs and fails to balance the selective catalytic reduction of NOx with the NH3 (NH3-SCR) performance. Herein, synergistic catalytic elimination of NOx and chlorobenzene has been originally demonstrated by using phosphotungstic acid (HPW) as a dechlorination agent to collaborate with CeO2. The conversion of chlorobenzene was over 80% at 270 °C, and the NOx conversion and N2 selectivity reached over 95% at 270-420 °C. HPW not only allowed chlorine species to leave as inorganic chlorine but also enhanced the Bro̷nsted acidity of CeO2. The NH4+ produced in the NH3-SCR process can effectively promote the dechlorination of chlorobenzene at low temperatures. HPW remained structurally stable in the synergistic reaction, resulting in good water resistance and long-term stability. This work provides a cheaper and more environmentally friendly strategy to address chlorine poisoning in the synergistic reaction and offers new guidance for multipollutant control.
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Affiliation(s)
- Huiqian Yang
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Aling Chen
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Fuli Wang
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Tianwei Lan
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Jin Zhang
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Xiaonan Hu
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Yongjie Shen
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Danhong Cheng
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
| | - Dengsong Zhang
- International Joint Laboratory of Catalytic Chemistry, State Key Laboratory of Advanced Special Steel, Innovation Institute of Carbon Neutrality, Research Center of Nano Science and Technology, Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China
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Lv X, Wu S, Shao S, Yan D, Xu W, Jia H, He H. Efficient Catalytic Elimination of Chlorobenzene Based on the Water Vapor-Promoting Effect within Mn-Based Catalysts: Activity Enhancement and Polychlorinated Byproduct Inhibition. Environ Sci Technol 2024; 58:3985-3996. [PMID: 38357760 DOI: 10.1021/acs.est.3c09020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2024]
Abstract
Achieving no or low polychlorinated byproduct selectivity is essential for the chlorinated volatile organic compounds (CVOCs) degradation, and the positive roles of water vapor may contribute to this goal. Herein, the oxidation behaviors of chlorobenzene over typical Mn-based catalysts (MnO2 and acid-modified MnO2) under dry and humid conditions were fully explored. The results showed that the presence of water vapor significantly facilitates the deep mineralization of chlorobenzene and restrains the formation of Cl2 and dichlorobenzene. This remarkable water vapor-promoting effect was conferred by the MnO2 substrate, which could suitably synergize with the postconstructed acidic sites, leading to good activity, stability, and desirable product distribution of acid-modified MnO2 catalysts under humid conditions. A series of experiments including isotope-traced (D2O and H218O) CB-TPO provided complete insights into the direct involvement of water molecules in chlorobenzene oxidation reaction and attributed the root cause of the water vapor-promoting effect to the proton-rich environment and highly reactive water-source oxygen species rather than to the commonly assumed cleaning effect or hydrogen proton transfer processes (generation of active OOH). This work demonstrates the application potential of Mn-based catalysts in CVOCs elimination under practical application conditions (containing water vapor) and provides the guidance for the development of superior industrial catalysts.
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Affiliation(s)
- Xuelong Lv
- Xiamen Key Laboratory of Materials for Gaseous Pollutant Control, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuaining Wu
- Xiamen Key Laboratory of Materials for Gaseous Pollutant Control, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Siting Shao
- Xiamen Key Laboratory of Materials for Gaseous Pollutant Control, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dongxu Yan
- Xiamen Key Laboratory of Materials for Gaseous Pollutant Control, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenjian Xu
- Xiamen Key Laboratory of Materials for Gaseous Pollutant Control, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hongpeng Jia
- Xiamen Key Laboratory of Materials for Gaseous Pollutant Control, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hong He
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- CAS Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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Long Y, Liu J, Chen M, Li R, Weng X, Wu Z. Catalytic destruction of chlorobenzene over K-OMS-2: Inhibition of high toxic byproducts via phosphate modification. J Environ Sci (China) 2023; 127:844-854. [PMID: 36522112 DOI: 10.1016/j.jes.2022.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 06/17/2023]
Abstract
In the process of catalytic destruction of chlorinated volatile organic compounds (CVOCs), the catalyst is prone to chlorine poisoning and produce polychlorinated byproducts with high toxicity and persistence, bringing great risk to atmospheric environment and human health. To solve these problems, this work applied phosphate to modify K-OMS-2 catalysts. The physicochemical properties of catalysts were determined by using X-ray powder diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), hydrogen temperature programmed reduction (H2-TPR), pyridine adsorption Fourier-transform infrared (Py-IR) and water temperature programmed desorption (H2O-TPD), and chlorobenzene was selected as a model pollutant to explore the catalytic performance and byproduct inhibition function of phosphating. Experimental results revealed that 1 wt.% phosphate modification yielded the best catalytic activity for chlorobenzene destruction, with the 90% conversion (T90) at approximately 247°C. The phosphating significantly decreased the types and yields of polychlorinated byproducts in effluent. After phosphating, we observed significant hydroxyl groups on catalyst surface, and the active center was transformed into Mn(IV)-O…H, which promoted the formation of HCl, and enhanced the dechlorination process. Furthermore, the enriched Lewis acid sites by phosphating profoundly enhanced the deep oxidation ability of the catalyst, which promoted a rapid oxidation of reaction intermediates, so as to reduce byproducts generation. This study provided an effective strategy for inhibiting the toxic byproducts for the catalytic destruction of chlorinated organics.
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Affiliation(s)
- Yunpeng Long
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jiajia Liu
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Meiling Chen
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Renna Li
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China.
| | - Xiaole Weng
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Engineering Research Center of Industrial Boiler and Furnace Flue Gas Pollution Control, Zhejiang University-Hangzhou Global Scientific and Technological Innovation Center, Hangzhou 311200, China.
| | - Zhongbiao Wu
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
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Tang H, Ma B, Bian Z, Wang H. Selective dechlorination degradation of chlorobenzenes by dual single-atomic Fe/Ni catalyst with M-N/M-O active sites synergistic. J Hazard Mater 2023; 443:130315. [PMID: 36368069 DOI: 10.1016/j.jhazmat.2022.130315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 10/25/2022] [Accepted: 11/01/2022] [Indexed: 06/16/2023]
Abstract
Removal and detoxification of chlorobenzenes have attracted public concern, multiple active sites single-atom Fe and single-atom Ni composite nitrogen-doped graphene (FeSA/CN/NiSA) cathode catalyst supplied generation and adsorption capacity of hydrogen and hydroxyl active species. M-O active sites coupled with M-N improved activity and stability of the catalyst, and decreased bond breaking energy barrier of C-Cl, FeSA/CN/NiSA-NiF cathode showed superior removal performance of chlorinated aromatic hydrocarbons (monochlorobenzene: 98.9%, dichlorobenzene: over 90.4%, trichlorobenzene: over 85.7%) and selectivity. Chlorobenzenes were dechlorinated under low stepwise voltage on the FeSA/CN/NiSA-NiF cathode. The efficiencies of stepwise dechlorination reactions of chlorobenzenes were all above 76%, Faradaic efficiencies were above 71.8%. The FeSA/CN/NiSA-NiF cathode was not sensitive to the molecular structure and has overcome the high energy barrier of chlorobenzenes molecular structure. The electrophilic attack of H*ads formed hyperconjugation bond weakened the possibility of the Cl atom forming a bond with the benzene ring, and was favorable for the Cl position to achieve single-electron transfer dechlorination. The selective stepwise dechlorination degradation of chlorobenzenes by FeSA/CN/NiSA-NiF cathode with multiple active sites demonstrated the advantaged performance of M-O and M-N active sites coupled synergistic in electrochemical reduction and degradation, providing a strategy for product-selective degradation of chlorinated aromatic hydrocarbons.
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Affiliation(s)
- Hanyu Tang
- College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Bei Ma
- College of Water Sciences, Beijing Normal University, Beijing 100875, PR China
| | - Zhaoyong Bian
- College of Water Sciences, Beijing Normal University, Beijing 100875, PR China.
| | - Hui Wang
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, PR China.
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Conte LO, Dominguez CM, Checa-Fernandez A, Santos A. Vis LED Photo-Fenton Degradation of 124-Trichlorobenzene at a Neutral pH Using Ferrioxalate as Catalyst. Int J Environ Res Public Health 2022; 19:9733. [PMID: 35955089 PMCID: PMC9367996 DOI: 10.3390/ijerph19159733] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/03/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
Chlorinated organic compounds (COCs) are among the more toxic organic compounds frequently found in soil and groundwater. Among these, toxic and low-degradable chlorobenzenes are commonly found in the environment. In this work, an innovative process using hydrogen peroxide as the oxidant, ferrioxalate as the catalyst and a visible light-emitting diode lamp (Vis LED) were applied to successfully oxidize 124-trichlorobenzene (124-TCB) in a saturated aqueous solution of 124-TCB (28 mg L-1) at a neutral pH. The influence of a hydrogen peroxide (HP) concentration (61.5-612 mg L-1), Fe3+ (Fe) dosage (3-10 mg L-1), and irradiation level (Rad) (I = 0.12 W cm-2 and I = 0.18 W cm-2) on 124-TCB conversion and dechlorination was studied. A D-Optimal experimental design combined with response surface methodology (RSM) was implemented to maximize the quality of the information obtained. The ANOVA test was used to assess the significance of the model and its coefficients. The maximum pollutant conversion at 180 min (98.50%) was obtained with Fe = 7 mg L-1, HP = 305 mg L-1, and I = 0.12 W cm-2. The effect of two inorganic anions usually presents in real groundwater (bicarbonate and chloride, 600 mg L-1 each) was investigated under those optimized operating conditions. A slight reduction in the 124-TCB conversion after 180 min of reaction was noticed in the presence of bicarbonate (8.31%) and chloride (7.85%). Toxicity was studied with Microtox® (Azur Environmental, Carlsbad, CA, USA) bioassay, and a remarkable toxicity decrease was found in the treated samples, with the inhibition proportional to the remaining 124-TCB concentration. That means that nontoxic byproducts are produced in agreement with the high dechlorination degrees noticed.
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Affiliation(s)
- Leandro O. Conte
- Chemical Engineering and Materials Department, Chemical Sciences Faculty, Complutense University of Madrid, 28040 Madrid, Spain
- Instituto de Desarrollo Tecnológico para la Industria Química (INTEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Universidad Nacional del Litoral (UNL), Santa Fe 3100, Argentina
| | - Carmen M. Dominguez
- Chemical Engineering and Materials Department, Chemical Sciences Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| | - Alicia Checa-Fernandez
- Chemical Engineering and Materials Department, Chemical Sciences Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| | - Aurora Santos
- Chemical Engineering and Materials Department, Chemical Sciences Faculty, Complutense University of Madrid, 28040 Madrid, Spain
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Han L, Wu W, Chen X, Chen M. Co-sorption/co-desorption mechanism of the mixed chlorobenzenes by fresh bulk and aged residual biochar. J Hazard Mater 2022; 429:128349. [PMID: 35101763 DOI: 10.1016/j.jhazmat.2022.128349] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 01/15/2022] [Accepted: 01/23/2022] [Indexed: 06/14/2023]
Abstract
Since little is known about the sorption/desorption behaviors of the mixed chlorobenzenes (CBs) on fresh and aged biochar, this study evaluated the co-sorption/co-desorption mechanism of the mixed monochlorobenzene (MCB), 1,2-dichlorobenzene (1,2-DCB) and 1,2,4-tirchlorobenzene (1,2,4-TCB) on the fresh bulk biochar derived from pinewood sawdust and corn straw under the heat treatment temperature (HTT) of 300 and 500 °C, and elucidated the aging-induced changes in the sorption/desorption of mixed CBs by biochar. The distinct sorption capacities of MCB< 1,2-DCB< 1,2,4-TCB were observed on all the tested biochar with the differences being further enhanced following the rise of HTT, as the main sorption mechanism was converted from phase partitioning to π-π interaction between graphitized biochar moieties and more hydrophobic aromatic chemicals. In comparison to the fresh biochar, the sorption suppression of the mixed CBs on the aged biochar was likely attributable to the reduction in accessibility to the aromatic carbon in biochar by introducing O-containing polar moieties on the biochar surfaces. Intriguingly, the kinetics of desorption was decreased with the aging of biochar may be caused by the increase in surface steric hindrance. These findings can provide new insights on understanding the co-sorption/co-desorption mechanism of the mixed CBs and help assess and manage the application of biochar on the treatment of contaminated soil and groundwater under field conditions.
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Affiliation(s)
- Lu Han
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Jiangsu Engineering Laboratory for Soil and Groundwater Remediation of Contaminated Sites, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Wenpei Wu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Jiangsu Engineering Laboratory for Soil and Groundwater Remediation of Contaminated Sites, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Xueyan Chen
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Jiangsu Engineering Laboratory for Soil and Groundwater Remediation of Contaminated Sites, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Mengfang Chen
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; Jiangsu Engineering Laboratory for Soil and Groundwater Remediation of Contaminated Sites, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
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Sun Y, Xu S, Bai B, Li L, Kang Y, Hu X, Liao Z, He C. Biotemplate Fabrication of Hollow Tubular Ce xSr 1-xTiO 3 with Regulable Surface Acidity and Oxygen Mobility for Efficient Destruction of Chlorobenzene: Intrinsic Synergy Effect and Reaction Mechanism. Environ Sci Technol 2022; 56:5796-5807. [PMID: 35321543 DOI: 10.1021/acs.est.2c00270] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Developing economic and applicable catalysts with elegant chlorine resistance and organic byproduct inhibition capability is of great significance for chlorinated volatile organic compounds (Cl-VOCs) eco-friendly purification. Here, ternary CexSr1-xTiO3 catalysts with tunable surface acidity and oxygen species mobility were creatively fabricated using the hollow tubular-structured fruit hair of Platanus (FHP; a widespread greenery waste) as the scaffolding biotemplate. It is shown that the oxygen vacancy (Ov) triggered by the presence of Ce can optimize the synergy between the Lewis acid sites (LAS) and Brønsted acid sites (BAS). High concentration of Ov and BAS promotes the C-Cl cleavage of chlorobenzene (CB) and accelerates the desorption of Cl• radicals as inorganic chlorine. Simultaneously, the strong electron transfer within Ti-Ce-Sr linkage increases the acidity of LAS, resulting in the superior reducibility of Ce0.4Sr0.6TiO3 and facilitating the deep oxidation of dechlorination intermediates. Additionally, the spatial confinement of the tubular structure remarkably accelerates the CB flow rate and reduces the residence time of byproducts over the prepared catalysts. Owing to these, CB can be efficiently destructed over Ce0.4Sr0.6TiO3 with selectivity of CO2 and inorganic chlorine dramatically enhanced, respectively, approximately 16 and 21 times at 275 °C compared to those of pure SrTiO3. The present work provides a feasible and promising strategy for engineering efficient catalysts for heterogeneous thermocatalytic reactions for industrial-scale Cl-CVOC destruction.
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Affiliation(s)
- Yukun Sun
- Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, School of Water and Environment, Chang'an University, Xi'an 710064, P. R. China
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, P. R. China
| | - Shuai Xu
- Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, School of Water and Environment, Chang'an University, Xi'an 710064, P. R. China
| | - Bo Bai
- Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, School of Water and Environment, Chang'an University, Xi'an 710064, P. R. China
| | - Lu Li
- Center of Nanomaterials for Renewable Energy, State Key Laboratory of Electrical Insulation and Power Equipment, School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, P. R. China
| | - Yu Kang
- Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, School of Water and Environment, Chang'an University, Xi'an 710064, P. R. China
| | - Xingquan Hu
- Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, School of Water and Environment, Chang'an University, Xi'an 710064, P. R. China
| | - Zehuihuang Liao
- Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region, Ministry of Education, School of Water and Environment, Chang'an University, Xi'an 710064, P. R. China
| | - Chi He
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, P. R. China
- National Engineering Laboratory for VOCs Pollution Control Material & Technology, University of Chinese Academy of Sciences, Beijing 101408, P. R. China
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Jin Q, Xu M, Lu Y, Yang B, Ji W, Xue Z, Dai Y, Wang Y, Shen Y, Xu H. Simultaneous catalytic removal of NO, mercury and chlorobenzene over WCeMnOx/TiO2-ZrO2: Performance study of microscopic morphology and phase composition. Chemosphere 2022; 295:133794. [PMID: 35124088 DOI: 10.1016/j.chemosphere.2022.133794] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 01/06/2022] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
Nitrogen oxides, mercury and chlorobenzene are important air pollutants emitted by waste incineration and other industries. Coordinated control of multiple pollutants has become an important technology for air pollution control. Through solid-phase structure control, the catalytic performance of the WCeMnOx/TiO2-ZrO2 catalyst for simultaneous catalytic removal of NO, mercury and simultaneous removal of NO and chlorobenzene were improved. MnWO4 improved the solid acidity of the catalyst and improved the catalytic activity at high temperature. The formation of Ce0·75Zr0·25O2, Ce2WO6, Ce2Zr2O7 and Ce2Ti2O7 improved the catalytic activity at low temperature. The presence of TiOSO4 would affect the valence of metal ions and the reduction of chemisorbed oxygen, thereby reducing the catalytic activity at low temperature. Within the same size range of nanoparticles, cyclic nanoparticles exposed more active sites due to their hollow structure, and their catalytic performance was better than spherical nanoparticles. The thickness of the circular nanoparticles of WCM/TZ-14 catalyst was about 14 nm, and the diameter was about 40 nm Ce0.75Zr0.25O2 and MnWO4 were also present in the phase composition. Therefore, it exhibited the best performance for simultaneous catalytic removal of NO, mercury and simultaneous removal of NO and chlorobenzene. The coincidence temperature window was 347-516 °C. Finally, WCM/TZ-14 catalyst followed both E-R and L-H mechanisms in the NH3-SCR reaction.
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Affiliation(s)
- Qijie Jin
- School of Environmental Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China; College of Materials Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China.
| | - Mutao Xu
- School of Environmental Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China
| | - Yao Lu
- School of Environmental Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China
| | - Bo Yang
- Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology (CICAEET), Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, PR China
| | - Wenyu Ji
- School of Environmental Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China
| | - Zhiwei Xue
- School of Chemistry and Chemical Engineering, Shandong University of Technology, Zibo, 255049, PR China
| | - Yi Dai
- School of Environmental Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China
| | - Yan Wang
- KAUST Catalysis Center (KCC), King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Yuesong Shen
- College of Materials Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China.
| | - Haitao Xu
- School of Environmental Science and Engineering, Nanjing Tech University, Nanjing, 210009, PR China.
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10
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Han MF, Wang C, Yang NY, Hu XR, Wang YC, Duan EH, Ren HW, Hsi HC, Deng JG. Performance enhancement of a biofilter with pH buffering and filter bed supporting material in removal of chlorobenzene. Chemosphere 2020; 251:126358. [PMID: 32155493 DOI: 10.1016/j.chemosphere.2020.126358] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 02/21/2020] [Accepted: 02/25/2020] [Indexed: 05/17/2023]
Abstract
Acidic substances, which produced during chlorinated volatile organic compounds, will corrode the commonly used packing materials, and then affect the removal performance of biofiltration. In this study, three biofilters with different filter bed structure were established to treat gaseous chlorobenzene. CaCO3 and 3D matrix material was added in filter bed as pH buffering material and filter bed supporting material, respectively. A comprehensive investigation of removal performance, biomass accumulation, microbial community, filter bed height, voidage, pressure drops, and specific surface area of the three biofilters was compared. The biofilter with CaCO3 and 3D matrix material addition presented stable removal performance and microbial community, and greater biomass density (209.9 kg biomass/m3 filter bed) and growth rate (0.033 d-1) were obtained by using logistic equation. After 200 days operation, the height, voidage, pressure drop, specific surface area of the filter bed consisted of perlite was 27.4 cm, 0.39, 32.8 Pa/m, 974,89 m2/m3, while those of the filter bed with CaCO3 addition was 28.2 cm, 0.43, 21.3 Pa/m, and 1021.03 m2/m3, and those of the filter bed with CaCO3 and 3D matrix material addition was 28.7 cm, 0.55, 17.4 Pa/m, and 1041.60 m2/m3. All the results verified the biofilter with CaCO3 and 3D matrix material addition is capable of sustaining the long-term performance of biofilters. CaCO3 could limit the changes of removal efficiency, microbial community and filter bed structure by buffering the pH variation. And 3D matrix material could maintain the filter bed structure by supporting the filter bed, regardless of the buffering effect.
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Affiliation(s)
- Meng-Fei Han
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin, 300072, China; School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, 050018, China
| | - Can Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin, 300072, China.
| | - Nan-Yang Yang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin, 300072, China
| | - Xu-Rui Hu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin, 300072, China; School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, 050018, China
| | - Yong-Chao Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin, 300072, China
| | - Er-Hong Duan
- School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, 050018, China
| | - Hong-Wei Ren
- School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang, Hebei, 050018, China.
| | - Hsing-Cheng Hsi
- Graduate Institute of Environmental Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Rd., Taipei, 106, Taiwan
| | - Ji-Guang Deng
- College of Environmental and Energy Engineering, Beijing University of Technology, Beijing, 100124, China
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11
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Li K, Yang B, Wang L. Performance evaluation of a biotrickling filter for the removal of gas-phase 1,2-dichlorobenzene: Influence of rhamnolipid and ferric ions. Chemosphere 2020; 250:126261. [PMID: 32109701 DOI: 10.1016/j.chemosphere.2020.126261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/12/2020] [Accepted: 02/15/2020] [Indexed: 06/10/2023]
Abstract
The aim of this study was to evaluate the influence of rhamnolipid (RL) and ferric ions on the performance of a biotrickling filter (BTF) for the removal of gas-phase 1,2-dichlorobenzene (o-DCB). A comprehensive investigation of microbial growth, pollutant solubility, extracellular polymeric substances (EPS) and enzymatic activity in o-DCB degradation by an isolated strain Bacillus cereus DL-1 with/without RL and Fe3+ were carried out using batch microcosm experiments. In addition, o-DCB removal performance, biofilm morphology, and microbial community structures in two identical lab-scale biotrickling filters (named BTF1 and BTF2) inoculated with strain DL-1 were studied. The batch microcosm experiments demonstrated that 120 mg L-1 RL and 4 mg L-1 Fe3+ could enhance the biodegradation of o-DCB, which may be due to promotion on bacterial growth, o-DCB solubilization, C12O enzyme activity, and polysaccharide (PS) and protein (PN) in EPS. Fourier transform infrared (FTIR) spectra indicated that the addition of RL with Fe3+ had notable effects on the functional groups of PS and PN in EPS. The experimental results in BTFs indicate that the removal efficiency of o-DCB decreased from 100% to 56.4% for BTF1, which was not fed with RL and Fe3+, and from 100% to 80.3% for BTF2, which was fed with RL and Fe3+, when the inlet loading rate increased from 4.88 to 102 g m-3 h-1 at an empty bed residence time of 60 s. In addition, the microbial adhesive strength and the microbial community structure were different among both BTFs, highlighting the positive effects of RL and Fe3+.
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Affiliation(s)
- Kang Li
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, PR China
| | - Bairen Yang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, PR China; School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng, Jiangsu, 224000, PR China
| | - Liping Wang
- School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, PR China; Engineering Research Center of Mine Ecological Construction, Ministry of Education, Xuzhou, Jiangsu, 221116, PR China.
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12
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Shang X, Yang L, Ouyang D, Zhang B, Zhang W, Gu M, Li J, Chen M, Huang L, Qian L. Enhanced removal of 1,2,4-trichlorobenzene by modified biochar supported nanoscale zero-valent iron and palladium. Chemosphere 2020; 249:126518. [PMID: 32213390 DOI: 10.1016/j.chemosphere.2020.126518] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 03/13/2020] [Accepted: 03/15/2020] [Indexed: 06/10/2023]
Abstract
Biochar pyrolysed at 300 °C, 500 °C, 700 °C was modified by hydrochloric acid (HCl), hydrofluoric acid (HF), sodium hydroxide (NaOH), hydrogen peroxide (H2O2), nitric acid (HNO3) and potassium permanganate (KMnO4), and subsequently evaluated for removal efficiency of 1,2,4-trichlorobenzene (1,2,4-TCB) by biochar supported nanoscale zero-valent iron (nZVI) and palladium (Pd) composites. Under the initial 1,2,4-TCB concentration of 10 mg L-1 and the solid-liquid ratio of 0.16 g L-1, the synthesized composites of nZVI-Pd with BC700 modified by HF (FBC700-nZVI-Pd) and nZVI-Pd with BC300 modified by NaOH (SBC300-nZVI-Pd) demonstrated significantly enhanced removal efficiencies for 1,2,4-TCB achieving 98.8% and 94.7% after 48 h, respectively. The physicochemical properties of biochar including specific surface area, aromaticity and hydrophobicity after the modification by HF and NaOH were improved. Increased the supporting sites for Fe/Pd nanoparticles and the contact between composites and 1,2,4-TCB were mainly responsible for enhanced removal efficiency for 1,2,4-TCB. Both the adsorption by biochar and reduction by Fe/Pd nanoparticles effectively contributed to the removal of 1,2,4-TCB. It is estimated that the proportion of reduction was about twice that of adsorption in the first 12 h, which produced 1,2-DCB, benzene and other degradation products. Therefore, biochar treated with HF and NaOH and supported Fe/Pd nanoparticles could be effective functional materials for remediation of groundwater contaminated by 1,2,4-TCB.
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Affiliation(s)
- Xiao Shang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China; School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, Shandong Province, China
| | - Lei Yang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Da Ouyang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China
| | - Bo Zhang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China; School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, Shandong Province, China
| | - Wenying Zhang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Mingyue Gu
- Nanjing Kaiye Environmental Technology Co Ltd, 8 Yuanhua Road, Innovation Building 106, Nanjing University Science Park, Nanjing, 210034, China
| | - Jing Li
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China; Nanjing Kaiye Environmental Technology Co Ltd, 8 Yuanhua Road, Innovation Building 106, Nanjing University Science Park, Nanjing, 210034, China
| | - Mengfang Chen
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Lihui Huang
- School of Environmental Science and Engineering, Shandong University, Qingdao, 266200, Shandong Province, China.
| | - Linbo Qian
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, Jiangsu Province, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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13
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Szopa C, Freissinet C, Glavin DP, Millan M, Buch A, Franz HB, Summons RE, Sumner DY, Sutter B, Eigenbrode JL, Williams RH, Navarro-González R, Guzman M, Malespin C, Teinturier S, Mahaffy PR, Cabane M. First Detections of Dichlorobenzene Isomers and Trichloromethylpropane from Organic Matter Indigenous to Mars Mudstone in Gale Crater, Mars: Results from the Sample Analysis at Mars Instrument Onboard the Curiosity Rover. Astrobiology 2020; 20:292-306. [PMID: 31880468 DOI: 10.1089/ast.2018.1908] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Chromatographic analysis of the Cumberland mudstone in Gale crater by the Sample Analysis at Mars (SAM) instrument revealed the detection of two to three isomers of dichlorobenzene. Their individual concentrations were estimated to be in the 0.5-17 ppbw range relative to the sample mass. We also report the first detection of trichloromethylpropane and the confirmation of the detection of chlorobenzene previously reported. Supporting laboratory experiments excluded the SAM internal background as the source of those compounds, thus confirming the organic carbon and chlorine of the newly detected chlorohydrocarbons are indigenous to the mudstone sample. Laboratory experiments also demonstrated that the chlorohydrocarbons were mainly produced from chemical reactions occurring in the SAM ovens between organic molecules and oxychlorines contained in the sample. The results we obtained show that meteoritic organics and tested chemical species (a polycyclic aromatic hydrocarbon, an amino acid, and a carboxylic acid) were plausible organic precursors of the chlorinated aromatic molecules detected with SAM, thus suggesting that they could be among the organic molecules present in the mudstone. Results from this study coupled with previously reported detections of chlorinated aromatics (<300 ppbw) indigenous to the same mudstone highlight that organics can be preserved from the harsh surface conditions even at shallow depth. The detection of new chlorohydrocarbons with SAM confirms that organic molecules should have been available in an environment favorable to life forms, strengthening the habitability aspect of Gale crater.
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Affiliation(s)
- Cyril Szopa
- LATMOS/IPSL, UVSQ Université Paris-Saclay, UPMC Univ. Paris 06, CNRS, Guyancourt, France
- Institut Universitaire de France, Paris, France
| | - Caroline Freissinet
- LATMOS/IPSL, UVSQ Université Paris-Saclay, UPMC Univ. Paris 06, CNRS, Guyancourt, France
| | - Daniel P Glavin
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Maeva Millan
- LATMOS/IPSL, UVSQ Université Paris-Saclay, UPMC Univ. Paris 06, CNRS, Guyancourt, France
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
- Department of Biology, Georgetown University, Washington, District of Columbia
| | - Arnaud Buch
- Laboratoire de Génie des Procédés et Matériaux (LGPM), EA 4038, Centrale-Supelec, Rue Joliot Curie, Gif-sur-Yvette, France
| | - Heather B Franz
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Roger E Summons
- Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Dawn Y Sumner
- Department of Earth and Planetary Sciences, University of California, Davis, California
| | - Brad Sutter
- Jacobs Technology, Inc., Johnson Space Center, National Aeronautics and Space Administration, Houston, Texas
| | - Jennifer L Eigenbrode
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Ross H Williams
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
- Department of Astronomy and CRESST II, University of Maryland, College Park, Maryland
| | - Rafael Navarro-González
- Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, Distrito Federal, México
| | - Melissa Guzman
- LATMOS/IPSL, UVSQ Université Paris-Saclay, UPMC Univ. Paris 06, CNRS, Guyancourt, France
| | - Charles Malespin
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Samuel Teinturier
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
- Universities Space Research Association, Goddard Earth Sciences Technology and Research Studies and Investigations, Greenbelt, Maryland
| | - Paul R Mahaffy
- Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland
| | - Michel Cabane
- LATMOS/IPSL, UVSQ Université Paris-Saclay, UPMC Univ. Paris 06, CNRS, Guyancourt, France
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14
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Palatucci ML, Waidner LA, Mack EE, Spain JC. Aerobic biodegradation of 2,3- and 3,4-dichloronitrobenzene. J Hazard Mater 2019; 378:120717. [PMID: 31203117 DOI: 10.1016/j.jhazmat.2019.05.110] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 05/24/2019] [Accepted: 05/30/2019] [Indexed: 06/09/2023]
Abstract
Dichloronitrobenzenes (DCNB) are intermediates in the production of dichloroanilines, which are key feedstocks for synthesis of diuron and other herbicides. Although DCNB is a major contaminant at certain chemical manufacturing sites, aerobic DCNB biodegradation is poorly understood and such sites have not been candidates for bioremediation. When a bench-scale aerobic fluidized- bed bioreactor was inoculated with samples from a DCNB contaminated site in Brazil 2,3-DCNB, 3,4-DCNB, 1,2-dichlorobenzene (o-DCB), and chlorobenzene (CB) were biodegraded simultaneously. Biodegradation of the mixture was complete even when the reactor was operated at high flow rates (1.6 h hydraulic residence time), and bacteria able to degrade the individual contaminants were isolated from the reactor by selective enrichment. The enrichments yielded 2 strains of bacteria able to degrade 3,4-DCNB and one able to degrade 2,3-DCNB. The isolates released nitrite during growth on the respective DCNB isomers under aerobic conditions. The draft genome sequence of Diaphorobacter sp. JS3050, which grew on 3,4-DCNB, revealed the presence of putative nitroarene dioxygenase genes, which is consistent with initial attack by a dioxygenase analogous to the initial steps in degradation of nitrobenzene and dinitrotoluenes. The results indicate clearly that the DCNB isomers are biodegradable under aerobic conditions and thus are candidates for natural attenuation/bioremediation.
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Affiliation(s)
- Mallory L Palatucci
- Center for Environmental Diagnostics & Bioremediation, University of West Florida, 11000 University Parkway, Pensacola, FL, 32514-5751, USA
| | - Lisa A Waidner
- Center for Environmental Diagnostics & Bioremediation, University of West Florida, 11000 University Parkway, Pensacola, FL, 32514-5751, USA
| | - E Erin Mack
- DuPont, Corporate Remediation Group, Chestnut Run Plaza 730/3170-6, P.O. Box 2915, 974 Centre Road, Wilmington, DE, 19805, USA
| | - Jim C Spain
- Center for Environmental Diagnostics & Bioremediation, University of West Florida, 11000 University Parkway, Pensacola, FL, 32514-5751, USA.
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15
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Dai S, Zheng Y, Zhao Y, Li Q, Niu D. Dechlorination and conversion mechanism of trichlorobenzene as a model compound of chlorine-containing wastes by different base-catalyzed combinations. Environ Sci Pollut Res Int 2019; 26:9480-9489. [PMID: 30726536 DOI: 10.1007/s11356-019-04221-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/10/2019] [Indexed: 06/09/2023]
Abstract
Chlorine-containing organic waste (COWs) is a big threat for the waste incineration because of the dioxin generation and equipment corrosion. Recently, dechlorination and detoxification of COWs is emergent in order to lower the environmental risk and treatment costs. In this study, base-catalyzed decomposition processes with different hydroxides, hydrogen donors, and catalysts were conducted for pre-treatment of COWs to reduce organic chlorine content, with the TCB as a model compound and industrial rectification residues for verification. Results showed that maximum chlorine retention efficiency (CRE) of four alkalis followed the order of KOH > NaOH-KOH > NaOH > Mg(OH)2, which were 98.3%, 93.4%, 97.2%, and 1.5%, respectively, and could be expressed as an apparent first-order reaction. The differences were resulted from the varying ionic potentials of the metal cations. Hydrogen donors (glycol, glycerol, paraffin oil, and PEG 200) acted as effective dechlorination regents follow the order of PEG > glycol > paraffin oil > glycerol. In addition, Fe, Ni, Cu, and activated carbon catalysts increased the CRE by 68.9% to 92.4%, 91.9%, 89.2%, and 73.3%, respectively. Residue analysis through X-ray diffraction and Fourier transform infrared spectroscopy revealed that KCl, sodium oxalate, and phenol were the main products and a plausible stepwise dechlorination pathway was proposed. The effectiveness of three optimized combinations including NaOH/PEG, KOH/PEG, and NaOH-KOH/PEG (with the Fe catalyst) was confirmed by using them for dechlorinating rectification residues, and they restrained 98.2%, 91.2%, and 94.6% of the chlorine, respectively. The organochlorine content decreased from 19.2 to 1.8% within 180 min, while inorganic chorine content increased from 1.5 to 18.9%, indicating the potential for COWs dechlorination.
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Affiliation(s)
- Shijin Dai
- College of Environmental Science and Engineering, Tongji University, Siping Rd. 1239, Shanghai, 200092, China
| | - Yilin Zheng
- College of Environmental Science and Engineering, Tongji University, Siping Rd. 1239, Shanghai, 200092, China
| | - Youcai Zhao
- College of Environmental Science and Engineering, Tongji University, Siping Rd. 1239, Shanghai, 200092, China
- Shanghai Institute of Pollution Control and Ecological Security, 1515 North Zhongshan Rd. (No. 2), Shanghai, 200092, China
| | - Qiang Li
- China Everbright Greentech Limited, Shenzhen, 518040, China
| | - Dongjie Niu
- College of Environmental Science and Engineering, Tongji University, Siping Rd. 1239, Shanghai, 200092, China.
- Shanghai Institute of Pollution Control and Ecological Security, 1515 North Zhongshan Rd. (No. 2), Shanghai, 200092, China.
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16
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Tong Z, Dong X, Yang S, Sun M, Gao T, Duan J, Cao H. Enantioselective effects of the chiral fungicide tetraconazole in wheat: Fungicidal activity and degradation behavior. Environ Pollut 2019; 247:1-8. [PMID: 30648617 DOI: 10.1016/j.envpol.2019.01.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 12/21/2018] [Accepted: 01/03/2019] [Indexed: 06/09/2023]
Abstract
Tetraconazole, a chiral triazole fungicide, is widely used for the prevention of plant disease in wheat fields. However, the chirality of pesticides like tetraconazole can cause diverse biological responses. Therefore, it is important that research is conducted to investigate the enantioselective effects of chiral enantiomers in this regard. The absolute configurations of two tetraconazole enantiomers were initially confirmed by ECD (Electrostatic circular dichroism). The bioassay test showed that the fungicidal activity of (R)-(+)-tetraconazole against two pathogens (R. cerealis and F. graminearum) was approximately 1.49-1.98 times greater than that for (S)-(-)- tetraconazole. Following recovery experiments, a modified QuEchERS (Quick, easy, cheap, effective, rugged, safe) method was established using UPLC-MS/MS (ultra-performance liquid chromatography tandem mass spectrometry). The mean recoveries from plant and soil sample ranged from 78.9% to 100.5% with intraday relative standard (RSDr) values of 0.8%-6.9% and interday relative standard (RSDR) values of 3.0%-5.2% respectively. The stereoselective degradation of tetraconazole in wheat meant that (S)-(-)-tetraconazole was more rapidly degraded than (R)-(+)-tetraconazole. Conversely, (R)-(+)-tetraconazole was preferentially degraded in wheat soil. These results will provide us with a greater understanding when assessing future environmental risk assessments and strategies that invoke pesticide reduction.
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Affiliation(s)
- Zhou Tong
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei, 230031, China
| | - Xu Dong
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei, 230031, China
| | - Shasha Yang
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei, 230031, China
| | - Mingna Sun
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei, 230031, China
| | - Tongchun Gao
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei, 230031, China
| | - Jinsheng Duan
- Institute of Plant Protection and Agro-Product Safety, Anhui Academy of Agricultural Sciences, Key Laboratory of Agro-Product Safety Risk Evaluation (Hefei), Ministry of Agriculture, Hefei, 230031, China.
| | - Haiqun Cao
- School of Plant Protection, Provincial Key Laboratory for Agri-Food Safety, Anhui Agricultural University, Hefei, 230036, China.
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17
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Nazari R, Rajić L, Ciblak A, Hernández S, Mousa IE, Zhou W, Bhattacharyya D, Alshawabkeh AN. Immobilized palladium-catalyzed electro-Fenton's degradation of chlorobenzene in groundwater. Chemosphere 2019; 216:556-563. [PMID: 30390586 PMCID: PMC6293191 DOI: 10.1016/j.chemosphere.2018.10.143] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 10/17/2018] [Accepted: 10/19/2018] [Indexed: 05/23/2023]
Abstract
This study investigates the effect of palladium (Pd) form on the electrochemical degradation of chlorobenzene in groundwater by palladium-catalyzed electro-Fenton (EF) reaction. In batch and flow-through column reactors, EF was initiated via in-situ electrochemical formation of hydrogen peroxide (H2O2) supported by Pd on alumina powder or by palladized polyacrylic acid (PAA) in a polyvinylidene fluoride (PVDF) membrane (Pd-PVDF/PAA). In a mixed batch reactor containing 10 mg L-1 Fe2+, 2 g L-1 of catalyst in powder form (1% Pd, 20 mg L-1 of Pd) and an initial pH of 3, chlorobenzene was degraded under 120 mA current following a first-order decay rate showing 96% removal within 60 min. Under the same conditions, a rotating Pd-PVDF/PAA disk produced 88% of chlorobenzene degradation. In the column experiment with automatic pH adjustment, 71% of chlorobenzene was removed within 120 min with 10 mg L-1 Fe2+, and 2 g L-1 catalyst in pellet form (0.5% Pd, 10 mg L-1 of Pd) under 60 mA. The EF reaction can be achieved under flow, without external pH adjustment and H2O2 addition, and can be applied for in-situ groundwater treatment. Furthermore, the rotating PVDF-PAA membrane with immobilized Pd-catalyst showed an effective and low maintenance option for employing Pd catalyst for water treatment.
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Affiliation(s)
- Roya Nazari
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, MA, 02115, USA
| | - Ljiljana Rajić
- Pioneer Valley Coral and Natural Science Institute, 1 Mill Valley Road, Hadley, MA, 01035, USA
| | - Ali Ciblak
- Geosyntec Consultants, 1255 Roberts Boulevard, suite 200, Kennesaw, GA, 30144, USA
| | - Sebastián Hernández
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY, 40506, USA
| | - Ibrahim E Mousa
- Department of Environmental Biotechnology, Genetic Engineering and Biotechnology Research Institute, University of Sadat City, Menoufia, 22857, Egypt
| | - Wei Zhou
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, MA, 02115, USA; Department of Energy Science and Engineering, Harbin Institute of Technology, Harbin, 150001, PR China
| | - Dibakar Bhattacharyya
- Department of Chemical and Materials Engineering, University of Kentucky, Lexington, KY, 40506, USA
| | - Akram N Alshawabkeh
- Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering, 360 Huntington Avenue, Boston, MA, 02115, USA.
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18
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Li Y, Yu G, Huang J, Wang B, Deng S, Wang Y. Catalytic decomposition of dioxins and other unintentional POPs in flue gas from a municipal waste incinerator (MWI) in China: a pilot testing. Environ Sci Pollut Res Int 2018; 25:31799-31804. [PMID: 27053043 DOI: 10.1007/s11356-016-6554-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/23/2016] [Indexed: 06/05/2023]
Abstract
Unintentionally produced persistent organic pollutants (UPOPs) include polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (dl-PCBs), pentachlorobenzene (PeCBz), and hexachlorobenzene (HxCBz). With the booming of municipal waste incinerators (MWIs) in China, the emission of UPOPs has generated great concern. As an alternative technology of dioxin control, catalytic decomposition has not been used in China, mainly due to the absence of national demonstration projects. Also, the simultaneous removal of various UPOPs has not been well investigated.In this study, a pilot-scale selective catalytic oxidative (SCO) system using a self-developed honeycomb catalyst was built and tested in a typical municipal waste incinerator (MWI) of China. The original concentration of PCDD/Fs in flue gas after the treatment of activated carbon injection (ACI) still exceeded the national emission standard (0.1 ng I-TEQ/Nm3), while the concentrations of PeCBz and HxCBz were one order of magnitude higher than that of PCDD/Fs. For the testing temperature varying from 300 to 200 °C, the removal efficiency of PCDD/Fs range from 39 to 95 %, followed by dl-PCBs with the range of 56-89 %. PeCBz and HxCBz were also removed, though their removal efficiencies were lower than those of PCDD/Fs and dl-PCBs. Both temperature and degree of chlorination influence the removal efficiencies.
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Affiliation(s)
- Yuancheng Li
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing, 100084, China
| | - Gang Yu
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing, 100084, China
| | - Jun Huang
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing, 100084, China.
| | - Bin Wang
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing, 100084, China
| | - Shubo Deng
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing, 100084, China
| | - Yujue Wang
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environment Simulation and Pollution Control (SKLESPC), Tsinghua University, Beijing, 100084, China
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19
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Smedes F. Silicone-water partition coefficients determined by cosolvent method for chlorinated pesticides, musks, organo phosphates, phthalates and more. Chemosphere 2018; 210:662-671. [PMID: 30031996 DOI: 10.1016/j.chemosphere.2018.07.054] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/06/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
To further support implementation of monitoring by passive sampling, robust sampler-water partition coefficients (Kpw) are required to convert data from passive sampler into aqueous phase concentrations. In this work silicone-water partition coefficients were determined for ∼80 hydrophobic organic contaminants using the cosolvent method. Partition coefficients (Kpm) were measured in pure water and water-methanol mixtures up to a methanol mole fraction of 0.3 (50% v/v). Subsequently, logKpw in pure water was determined as the intercept of linear regression of the logKpm with the corresponding methanol mole fractions. LogKpw were determined for phthalates, musks, organo phosphorus flame-retardants, chlorobenzenes, pesticides, some PCBs and a number of miscellaneous compounds. The median standard error and 95% confidence interval of the measured logKpw was 0.06 and 0.13, respectively. The overall relationship between Kpw and Kow seems insufficient to predict Kpw for unknown compounds. Prediction may work within a group of compounds with similar nature, e.g. homologues but HCH isomers having the same Kow exhibit Kpw ranging over an order of magnitude. Long alkyl-chain phthalates and tris(2-ethylhexyl) phosphate; all having a molecular volume >400 Å3, deviated the most from the Kpw-Kow relationship.
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Affiliation(s)
- Foppe Smedes
- Masaryk University, Faculty of Science, Research Centre for Toxic Compounds in the Environment (RECETOX), Kamenice 753/5, 625 00, Brno, Czech Republic; Deltares, PO. Box 85467, 3508 AL, Utrecht, the Netherlands.
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20
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Zhao X, Zeng X, Qin Y, Li X, Zhu T, Tang X. An experimental and theoretical study of the adsorption removal of toluene and chlorobenzene on coconut shell derived carbon. Chemosphere 2018; 206:285-292. [PMID: 29753291 DOI: 10.1016/j.chemosphere.2018.04.126] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 04/02/2018] [Accepted: 04/20/2018] [Indexed: 06/08/2023]
Abstract
The adsorption performance of toluene and chlorobenzene on prepared coconut shell derived carbon (CDC) is investigated and compared with commercial activated carbon (CAC) by experiment and theory calculation. Textural properties of prepared adsorbents are characterized by N2 adsorption, infrared spectra (FT-IR), Raman spectra and X-ray photoelectron spectra (XPS). Adsorption isotherms of toluene and chlorobenzene are obtained and fitted using structure optimizations, Grand Canonical Monte Carlo (GCMC) simulation and thermodynamic models. The results indicate that CDC shows better volatile organic compounds (VOCs) removal performance than CAC, and chlorobenzene is easily adsorbed than toluene. On the aspect of textural characteristics, CDC possesses more micropores ratio and narrower pore size distribution than CAC. Furthermore, amounts of electron-withdrawing carbonyl groups on the CAC surface reduce the electron density of adsorbents, thus weakening the interaction between VOCs and adsorbents. On the aspect of model fitting, the Yoon and Nelson (Y-N) and Dubinin-Astakhov (D-A) models can well describe the dynamic adsorption and the adsorption equilibrium of toluene and chlorobenzene on CDC respectively. It is believed that substituent groups of adsorbates, making the charge distribution deviate, lead to adsorption potentials of chlorobenzene larger than toluene. In general, both the pore structure and the surface property of adsorbents affect the VOCs adsorption behaviors on CDC.
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Affiliation(s)
- Xiaoyan Zhao
- School of Space and Environment, Beihang University, Beijing, 100191, PR China
| | - Xiaolan Zeng
- School of Space and Environment, Beihang University, Beijing, 100191, PR China
| | - Yu Qin
- School of Space and Environment, Beihang University, Beijing, 100191, PR China
| | - Xiang Li
- School of Space and Environment, Beihang University, Beijing, 100191, PR China.
| | - Tianle Zhu
- School of Space and Environment, Beihang University, Beijing, 100191, PR China
| | - Xiaolong Tang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China
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21
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Ren Z, Lu Y, Li Q, Sun Y, Wu C, Ding Q. Occurrence and characteristics of PCDD/Fs formed from Chlorobenzenes production in China. Chemosphere 2018; 205:267-274. [PMID: 29702346 DOI: 10.1016/j.chemosphere.2018.04.112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 04/17/2018] [Accepted: 04/18/2018] [Indexed: 06/08/2023]
Abstract
China had a large production capacity of chlorobenzenes. An extensive investigation was conducted to understand the occurrence and characteristics of PCDD/Fs from four chlorobenzene production plants. The concentrations of PCDD/Fs in mono-CB production and in a new di-CB production routine were revealed. Concentrations of PCDD/Fs in residues, byproducts, products and wastewater varied between 8.4*103-4.0*106 ng TEQ/kg, 1.5-5.0*104 ng TEQ/kg, ND∼0.12 ng TEQ/kg and 6.0*104-9.1*104 pg TEQ/L, respectively. OCDF, 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, and 2,3,7,8-TeCDF were the most abundant congeners of the 17 2,3,7,8-substituted PCDD/Fs. In most samples, PCDFs contributed more than 99% of the total TEQs of PCDD/Fs, in which 2,3,4,7,8-PeCDF was the dominating contributor. It is inferred PCDFs were mainly formed in the chlorination reactions. The emission factors were suggested and the amount of PCDD/Fs formed in CB production was estimated to be 450 g TEQ in 2012. Residue, byproduct and wastewater were potentially the main pathways of PCDD/Fs to the environmental releases.
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Affiliation(s)
- Zhiyuan Ren
- Foreign Economic Cooperation Office, Ministry of Environmental Protection, Beijing, PR China.
| | - Yong Lu
- CSD IDEA (Beijing) Environmental Test & Analysis Co. Ltd., Beijing, PR China
| | - Qiushuang Li
- Foreign Economic Cooperation Office, Ministry of Environmental Protection, Beijing, PR China
| | - Yangzhao Sun
- Foreign Economic Cooperation Office, Ministry of Environmental Protection, Beijing, PR China
| | - Changmin Wu
- CSD IDEA (Beijing) Environmental Test & Analysis Co. Ltd., Beijing, PR China
| | - Qiong Ding
- Foreign Economic Cooperation Office, Ministry of Environmental Protection, Beijing, PR China
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22
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Qiao W, Ye S, Wu J, Zhang M. Surfactant-Enhanced Electroosmotic Flushing in a Trichlorobenzene Contaminated Clayey Soil. Ground Water 2018; 56:673-679. [PMID: 29320601 DOI: 10.1111/gwat.12631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 12/01/2017] [Accepted: 12/11/2017] [Indexed: 06/07/2023]
Abstract
Remediation of the sites contaminated with organic contaminants, such as chlorobenzenes, remains a challenging issue. Electroosmotic flushing can be a promising approach which is based on mechanism of electrokinetic remediation for removal of organic contaminants from fluids in low-permeability soil. To select an optimum surfactant that can effectively enhance electroosmotic flushing, three common surfactants, Triton X-100 (EK2), Tween 80 (EK3), and a mixture of sodium dodecyl sulfate and Triton X-100 (EK4) buffered with Na2 HPO4 /NaH2 PO4 solution, were tested. The efficiency of each kind of surfactant was evaluated using a three-dimensional box filled with a clayey soil spiked with 1,2,4-trichlorobenzene, and compared with a test (EK1) without surfactant. The results demonstrated that the buffer solutions efficiently neutralized H+ and OH- produced by electrolysis. EK3 with Tween 80 added in the flushing solution reached the highest electroosmotic permeability of 10-4 cm2 /v/s and achieved a notably high cumulative electroosmotic flow (EOF) of 5067 mL within 6 d, which was 6.3, 3.4, and 4.2 times higher than that in EK1, EK2, and EK4, respectively. There were 420 mL more cumulative EOF obtained after 50 h of electrical application in EK4 than in EK2. The introduction of nonreactive ions can increase the current, thereby benefiting the EOF. Both the higher pH caused by the buffer and the application of nonionic surfactants can make the zeta potential more negative, thereby increasing the EOF. Tween 80 can be recommended as the best flushing solution for removing organic contaminants from sites when electrokinetic remediation is applied.
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Affiliation(s)
- Wenjing Qiao
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing, 210023, China
| | | | - Jichun Wu
- Key Laboratory of Surficial Geochemistry, Ministry of Education, School of Earth Sciences and Engineering, Nanjing University, Nanjing, 210023, China
| | - Ming Zhang
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8567, Japan
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23
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Passeport E, Zhang N, Wu L, Herrmann H, Sherwood Lollar B, Richnow HH. Aqueous photodegradation of substituted chlorobenzenes: Kinetics, carbon isotope fractionation, and reaction mechanisms. Water Res 2018; 135:95-103. [PMID: 29459118 DOI: 10.1016/j.watres.2018.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/03/2018] [Accepted: 02/05/2018] [Indexed: 06/08/2023]
Abstract
Substituted chlorobenzenes are the basic substructure of many surface water contaminants. In this study, the isotope fractionation and reaction mechanisms involved during the aqueous direct and indirect photodegradation of CH3-, Cl-, and NO2- substituted chlorobenzenes were investigated in laboratory experiments. Only 4-nitrochlorobenzene showed slow but isotopically fractionating direct photolysis. During indirect photodegradation using UV/H2O2-generated OH radicals, the pseudo first-order reaction rate constants increased in the order of the NO2- < Cl- < CH3- substituted chlorobenzenes. The most pronounced carbon enrichment factors were observed for nitrochlorobenzenes (up to -4.8 ± 0.5‰), whereas the lowest were for chlorotoluenes (≤-1.0 ± 0.1‰). As the substituents became more electron-withdrawing, the activation energy barrier increased, leading to slower reaction rates, and the transition state changed to a more symmetrical or less reactant-like structure, resulting in larger apparent kinetic isotope effects. The results suggest that the rate-determining step in the reaction with OH radicals was the addition of the electrophile to the benzene ring. Even though further research is needed to quantify isotope fractionation during other transformation processes, these results showed evidence that compound specific isotope analysis can be used as a diagnostic tool for the fate of substituted chlorobenzenes in water.
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Affiliation(s)
- Elodie Passeport
- Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, ON M5S 3B1, Canada.
| | - Ning Zhang
- Department of Isotope Biogeochemistry, Helmholtz Center for Environmental Research UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Langping Wu
- Department of Isotope Biogeochemistry, Helmholtz Center for Environmental Research UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Hartmut Herrmann
- TROPOS Leibniz Institute for Tropospheric Research, Atmospheric Chemistry Department (ACD), Permoserstrasse 15, 04318 Leipzig, Germany
| | - Barbara Sherwood Lollar
- Department of Earth Sciences, University of Toronto, 22 Russell Street, Toronto, ON M5S 3B1, Canada
| | - Hans-Hermann Richnow
- Department of Isotope Biogeochemistry, Helmholtz Center for Environmental Research UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
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24
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Wan XF, Guo C, Liu Y, Chai XS, Li Y, Chen G. Kinetic research on dechlorinating dichlorobenzene in aqueous system by nano-scale nickel/iron loaded with CMC/NFC hydrogel. Chemosphere 2018; 194:297-305. [PMID: 29216549 DOI: 10.1016/j.chemosphere.2017.11.142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 10/28/2017] [Accepted: 11/23/2017] [Indexed: 06/07/2023]
Abstract
In this study, we reported on the nano-scale nickel/iron particles loaded in carboxymethyl/nanofibrillated cellulose (CMC/NFC) hydrogel for the dechlorination of o-dichlorobenzene (DCB) in aqueous solution. The biodegradable hydrogel may provide an ideal supporting material for fastening the bimetallic nano-scale particles, which was examined and characterized by TEM, SEM-EDX, FT-IR and BET. The performance of the selected bimetallic particles was evaluated by conducting the dechlorination of DCB in the solution under different reaction conditions (e.g., pH, dosage of nickel/iron nanoparticles and temperature). The results showed that about 70% of DCB could be dechlorinated at 20 °C in 8 h, which indicated that the immobilized reactive material had a high reduction activity when Ni/Fe loading dosage in the hydrogel (18 wt%) was considered. Moreover, the reduction behavior agreed to the pseudo-first order reaction, in which the dechlorination rate was irrelative to the pH aqueous solution. A kinetic model for predicting the concentration of DCB during the reduction reaction was established based on the experimental data.
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Affiliation(s)
- Xiao-Fang Wan
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China.
| | - Congbao Guo
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
| | - Yu Liu
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
| | - Xin-Sheng Chai
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
| | - Youming Li
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
| | - Guangxue Chen
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, China
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25
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Bullot L, Vieira-Sellaï L, Chaplais G, Simon-Masseron A, Daou TJ, Patarin J, Fiani E. Adsorption of 1,2-dichlorobenzene and 1,2,4-trichlorobenzene in nano- and microsized crystals of MIL-101(Cr): static and dynamic gravimetric studies. Environ Sci Pollut Res Int 2017; 24:26562-26573. [PMID: 28952020 DOI: 10.1007/s11356-017-0242-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 09/19/2017] [Indexed: 06/07/2023]
Abstract
This work aims to highlight the promising adsorption capacity and kinetic of (poly)chlorobenzene pollutants in the hybrid MIL-101(Cr) type material for technological uses in industrial waste exhaust decontamination. The influence of the MIL-101(Cr) crystal size (nano- and microcrystals) on the adsorption behavior was studied in static and dynamic modes. For this purpose, crystals of MIL-101(Cr) in nano- and micrometric sizes were synthesized and fully characterized. Their sorption properties regarding 1,2-dichlorobenzene were examined using gravimetric method in dynamic (p/p° = 0.5) and static (p/p° = 1) modes at room temperature. 1,2,4-trichlorobenzene adsorption was only performed under static mode because of its too low vapor pressure. 1,2-dichlorobenzene and 1,2,4-trichlorobenzene were used to mimic 2,3-dichlorodibenzo-p-dioxin and 1,2,3,4-tetrachlorodibenzo-p-dioxin, respectively, and more largely dioxin compounds. Adsorptions of these probes were successfully carried out in nano- and microcrystals of MIL-101(Cr). Indeed, in static mode (p/p° = 1) and at room temperature, nanocrystals adsorb 2266 molecules of 1,2-dichlorobenzene and 2093 molecules of 1,2,4-trichlorobenzene per unit cell, whereas microcrystals adsorb 1871 molecules of 1,2-dichlorobenzene and 1631 molecules of 1,2,4-trichlorobenzene per unit cell. In dynamic mode, the 1,2-dichlorobenzene adsorbed amounts are substantially similar to those obtained in static mode. However, the adsorption kinetics are different because of a different scheme of diffusivity of the adsorbate between the two modes. To the best of our knowledge, these adsorption capacities of MIL-101(Cr) as adsorbent for polychlorobenzenes trapping have never been referenced. MIL-101(Cr) appears as a promising material for technological uses in industrial waste exhaust decontamination.
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Affiliation(s)
- Laetitia Bullot
- Université de Strasbourg (Unistra), Université de Haute Alsace (UHA), Axe Matériaux à Porosité Contrôlée (MPC), Institut de Science des Matériaux de Mulhouse (IS2M), UMR CNRS 7361, ENSCMu, 3 bis rue Alfred Werner, 68093, Mulhouse Cedex, France
- French Agency for Environment and Energy Management (ADEME), 20 avenue du Grésillé, BP 90406, 49004, Angers Cedex 01, France
| | - Ludivine Vieira-Sellaï
- Université de Strasbourg (Unistra), Université de Haute Alsace (UHA), Axe Matériaux à Porosité Contrôlée (MPC), Institut de Science des Matériaux de Mulhouse (IS2M), UMR CNRS 7361, ENSCMu, 3 bis rue Alfred Werner, 68093, Mulhouse Cedex, France
| | - Gérald Chaplais
- Université de Strasbourg (Unistra), Université de Haute Alsace (UHA), Axe Matériaux à Porosité Contrôlée (MPC), Institut de Science des Matériaux de Mulhouse (IS2M), UMR CNRS 7361, ENSCMu, 3 bis rue Alfred Werner, 68093, Mulhouse Cedex, France.
| | - Angélique Simon-Masseron
- Université de Strasbourg (Unistra), Université de Haute Alsace (UHA), Axe Matériaux à Porosité Contrôlée (MPC), Institut de Science des Matériaux de Mulhouse (IS2M), UMR CNRS 7361, ENSCMu, 3 bis rue Alfred Werner, 68093, Mulhouse Cedex, France
| | - Toufic Jean Daou
- Université de Strasbourg (Unistra), Université de Haute Alsace (UHA), Axe Matériaux à Porosité Contrôlée (MPC), Institut de Science des Matériaux de Mulhouse (IS2M), UMR CNRS 7361, ENSCMu, 3 bis rue Alfred Werner, 68093, Mulhouse Cedex, France
| | - Joël Patarin
- Université de Strasbourg (Unistra), Université de Haute Alsace (UHA), Axe Matériaux à Porosité Contrôlée (MPC), Institut de Science des Matériaux de Mulhouse (IS2M), UMR CNRS 7361, ENSCMu, 3 bis rue Alfred Werner, 68093, Mulhouse Cedex, France
| | - Emmanuel Fiani
- French Agency for Environment and Energy Management (ADEME), 20 avenue du Grésillé, BP 90406, 49004, Angers Cedex 01, France
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26
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Djohan D, Yu J, Connell D. Partition kinetics of chlorobenzenes in a sediment-water system. Chemosphere 2017; 186:938-947. [PMID: 28838040 DOI: 10.1016/j.chemosphere.2017.08.060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/05/2017] [Accepted: 08/12/2017] [Indexed: 06/07/2023]
Abstract
The partition kinetics of chlorobenzenes (CBs) in a sediment-water system were studied to provide a basis for understanding the compounds' behaviour in the natural aquatic environment. A series of chlorobenzenes (CBs) 1,4-dichlorobenzene (DCB), 1,3,5-trichlorobenzene (TCB), 1,2,4,5-tetrachlorobenzene (TeCB), pentachlorobenzene (QCB), and hexachlorobenzene (HCB) were spiked to the sediment, and the concentrations of CBs both in sediment and water were measured at six different mixing time periods (0.17, 1, 4, 12, 24 and 48 h). A partition kinetics model was developed to determine kinetics rate constants. Adsorption rate constants increased (DCB 15.3; HCB 26.3 L kg-1 h-1) while desorption rate constants decreased (DCB 0.41; HCB 0.01 h-1) with KOW values. The times to reach equilibrium in the system were between 6.7 h (HCB) and 14.3 h (TeCB), with no specific pattern related to the KOW values of CBs. The kinetics of CBs were fitted to a first-order kinetics with a single-compartment model. QSAR analysis showed strong linear relationships between kinetics rate constants and physicochemical properties.
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Affiliation(s)
- Djohan Djohan
- School of Environmental Biology, Duta Wacana Christian University, Yogyakarta, DIY 55224, Indonesia.
| | - Jimmy Yu
- School of Engineering, Griffith University, Brisbane, QLD 4111, Australia
| | - Des Connell
- School of Environment, Griffith University, Brisbane, QLD 4111, Australia
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27
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Ramadan A. Assessment of spatial variation of ambient volatile organic compound levels at a power station in Kuwait. J Air Waste Manag Assoc 2017; 67:1170-1179. [PMID: 27700694 DOI: 10.1080/10962247.2016.1241196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2016] [Accepted: 09/13/2016] [Indexed: 06/06/2023]
Abstract
UNLABELLED Twenty-four-hour integrated ambient air samples were collected in canisters at 10 locations within Kuwait's major power station: Doha West Power Station to assess the spatial distribution of volatile organic compounds (VOCs) within the perimeter of the station. A total of 30 samples, i.e., three samples per location, were collected during February and March. The samples were analyzed using a gas chromatography with flame ionization detection (GC-FID) system and following the U.S. EPA Method TO-14A with modification. The results reflected the emission activities on the site and the meteorological conditions during sampling. Generally speaking, there was a negative correlation between the ambient temperature and the VOC concentrations, which indicates the sources were local. The halogenated compounds formed the highest proportion (i.e. 50-75 %) of the total VOC concentrations at the ten locations. 1,2,4-Trichlorobenzene and Vinyl Chloride concentrations were the highest amongst the other halogenated compounds. The aromatic compounds formed the least proportion (i.e. 1-4%) of the total VOC levels at all locations with Toluene having the highest concentrations amongst the aromatic compounds at seven locations. Propene, which is a major constituent of the fuel used, was the highest amongst the aliphatic compounds. The findings of this study and other relevant work suggests the measured VOC levels were the highest over the year, nevertheless, further work is required to assess the precisely temporal variation of VOC due to change in meteorological conditions and the emission rates. IMPLICATIONS Assessment of VOC concentrations around a power plant in Kuwait during the peak season showed halogenated compounds to be the dominant group. The calculated indoor concentrations were lower than those reported in a residential area about 12 km away.
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Affiliation(s)
- Ashraf Ramadan
- a Environmental Pollution and Climate Program , Environment and Life Sciences Research Center, Kuwait Institute for Scientific Research , Safat , Kuwait
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28
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Pei G, Zhu Y, Cai X, Shi W, Li H. Surfactant flushing remediation of o-dichlorobenzene and p-dichlorobenzene contaminated soil. Chemosphere 2017; 185:1112-1121. [PMID: 28772354 DOI: 10.1016/j.chemosphere.2017.07.098] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/03/2017] [Accepted: 07/18/2017] [Indexed: 06/07/2023]
Abstract
Surfactant-enhanced remediation is used to treat dichlorobenzene (DCB) contaminated soil. In this study, soil column experiments were conducted to investigate the removal efficiencies of o-dichlorobenzene (o-DCB) and p-dichlorobenzene (p-DCB) from contaminated soil using micellar solutions of biosurfactants (saponin, alkyl polyglycoside) compare to a chemically synthetic surfactant (Tween 80). Leachate was collected and analyzed for o-DCB and p-DCB content. In addition, soil was analyzed to explore the effect of surfactants on soil enzyme activities. Results showed that the removal efficiency of o-DCB and p-DCB was highest for saponin followed by alkyl polyglycoside and Tween 80. The maximum o-DCB and p-DCB removal efficiencies of 76.34% and 80.43%, respectively, were achieved with 4 g L-1 saponin solution. However, an opposite result was observed in the cumulative mass of o-DCB and p-DCB in leachate. The cumulative extent of o-DCB and p-DCB removal by the biosurfactants saponin and alkyl polyglycoside was lower than that of the chemically synthetic surfactant Tween 80 in leachate. Soil was also analyzed to explore the effect of surfactants on soil enzyme activities. The results indicated that surfactants were potentially effective in facilitating soil enzyme activities. Thus, it was confirmed that the biosurfactants saponin and alkyl polyglycoside could be used for remediation of o-DCB and p-DCB contaminated soil.
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Affiliation(s)
- Guangpeng Pei
- School of Environment Science and Resources, Shanxi University, Taiyuan, Shanxi 030006, China; Institute of Resources and Environment Engineering, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Yuen Zhu
- School of Environment Science and Resources, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Xiatong Cai
- School of Environment Science and Resources, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Weiyu Shi
- Chongqing Key Laboratory of Karst Environment, School of Geographical Sciences, Southwest University, Chongqing 400715, China.
| | - Hua Li
- School of Environment Science and Resources, Shanxi University, Taiyuan, Shanxi 030006, China.
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Weng X, Sun P, Long Y, Meng Q, Wu Z. Catalytic Oxidation of Chlorobenzene over Mn xCe 1-xO 2/HZSM-5 Catalysts: A Study with Practical Implications. Environ Sci Technol 2017; 51:8057-8066. [PMID: 28614947 DOI: 10.1021/acs.est.6b06585] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Industrial-use catalysts usually encounter severe deactivation after long-term operation for catalytic oxidation of chlorinate volatile organic compounds (CVOCs), which becomes a "bottleneck" for large-scale application of catalytic combustion technology. In this work, typical acidic solid-supported catalysts of MnxCe1-xO2/HZSM-5 were investigated for the catalytic oxidation of chlorobenzene (CB). The activation energy (Ea), Brønsted and Lewis acidities, CB adsorption and activation behaviors, long-term stabilities, and surficial accumulation compounds (after aging) were studied using a range of analytical techniques, including XPS, H2-TPR, pyridine-IR, DRIFT, and O2-TP-Ms. Experimental results revealed that the Brønsted/Lewis (B/L) ratio of MnxCe1-xO2/HZSM-5 catalysts could be adjusted by ion exchange of H• (in HZSM-5) with Mnn+ (where the exchange with Ce4+ did not distinctly affect the acidity); the long-term aged catalysts could accumulate ca. 14 organic compounds at surface, including highly toxic tetrachloromethane, trichloroethylene, tetrachloroethylene, o-dichlorobenzene, etc.; high humid operational environment could ensure a stable performance for MnxCe1-xO2/HZSM-5 catalysts; this was due to the effective removal of Cl• and coke accumulations by H2O washing, and the distinct increase of Lewis acidity by the interaction of H2O with HZSM-5. This work gives an in-depth view into the CB oxidation over acidic solid-supported catalysts and could provide practical guidelines for the rational design of reliable catalysts for industrial applications.
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Affiliation(s)
- Xiaole Weng
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Natural Resources and Environmental Science, Zhejiang University , 310058 Hangzhou, P. R. China
- Zhejiang Provincial Engineering Research Centre of Industrial Boiler & Furnace Flue Gas Pollution Control, 388 Yuhangtang Road, 310058 Hangzhou, P. R. China
| | - Pengfei Sun
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Natural Resources and Environmental Science, Zhejiang University , 310058 Hangzhou, P. R. China
| | - Yu Long
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Natural Resources and Environmental Science, Zhejiang University , 310058 Hangzhou, P. R. China
| | - Qingjie Meng
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Natural Resources and Environmental Science, Zhejiang University , 310058 Hangzhou, P. R. China
| | - Zhongbiao Wu
- Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, College of Natural Resources and Environmental Science, Zhejiang University , 310058 Hangzhou, P. R. China
- Zhejiang Provincial Engineering Research Centre of Industrial Boiler & Furnace Flue Gas Pollution Control, 388 Yuhangtang Road, 310058 Hangzhou, P. R. China
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30
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Wang H, Yi S, Cao X, Fang Z, Li X. Reductive dechlorination of hexachlorobenzene subjected to several conditions in a bioelectrochemical system. Ecotoxicol Environ Saf 2017; 139:172-178. [PMID: 28135664 DOI: 10.1016/j.ecoenv.2017.01.039] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 01/04/2017] [Accepted: 01/22/2017] [Indexed: 06/06/2023]
Abstract
A microbial fuel cell (MFC) is a very promising way to remove organic pollutants. Hexachlorobenzene (HCB) is a widely used agricultural pesticide. In this study, single-chamber and membrane-less soil MFCs were constructed. The HCB was degraded to pentachlorobenzene (PeCB), tetrachlorobenzene (TeCB), and trichlorobenzene (TCB) in sequence by a reductive dechlorination process in soil MFCs. The influences of the external resistance, concentration of phosphate buffer, and electrode spacing in soil MFCs on the degradation rate and removal efficiency of HCB were analyzed. The results showed that the degradation rate and removal efficiency of HCB were increased when the external resistance decreased from 2000 to 20Ω, and also when the concentration of phosphate buffer increased. The anode area played a significant role in dechlorination of HCB. Altering the spacing of the reducing electrode resulted in a lower ohmic resistance in the soil MFCs. The ohmic resistance was negatively correlated with the removal efficiency and degradation rate (P<0.05). In conclusion, HCB removal efficiency could be enhanced by soil MFCs, the performance of which was improved by a decrease in external resistance and internal resistance, and an increase in phosphate buffer concentration, rather than just by shortening the electrode spacing.
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Affiliation(s)
- Hui Wang
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Shuyu Yi
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Xian Cao
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Zhou Fang
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
| | - Xianning Li
- School of Energy and Environment, Southeast University, Nanjing 210096, China.
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31
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Jiang L, Nie G, Zhu R, Wang J, Chen J, Mao Y, Cheng Z, Anderson WA. Efficient degradation of chlorobenzene in a non-thermal plasma catalytic reactor supported on CeO 2/HZSM-5 catalysts. J Environ Sci (China) 2017; 55:266-273. [PMID: 28477821 DOI: 10.1016/j.jes.2016.07.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 05/20/2016] [Accepted: 07/09/2016] [Indexed: 06/07/2023]
Abstract
Chlorobenzene removal was investigated in a non-thermal plasma reactor using CeO2/HZSM-5 catalysts. The performance of catalysts was evaluated in terms of removal and energy efficiency. The decomposition products of chlorobenzene were analyzed. The results show that CeO2/HZSM-5 exhibited a good catalytic activity, which resulted in enhancements of chlorobenzene removal, energy efficiency, and the formation of lower amounts of by-products. With regards to CO2 selectivity, the presence of catalysts favors the oxidation of by-products, leading to a higher CO2 selectivity. With respect to ozone, which is considered as an unavoidable by-product in air plasma reactors, a noticeable decrease in its concentration was observed in the presence of catalysts. Furthermore, the stability of the catalyst was investigated by analyzing the evolution of conversion in time. The experiment results indicated that CeO2/HZSM-5 catalysts have excellent stability: chlorobenzene conversion only decreased from 78% to 60% after 75hr, which means that the CeO2/HZSM-5 suffered a slight deactivation. Some organic compounds and chlorinated intermediates were adsorbed or deposited on the catalysts surface as shown by the results of Fourier Transform Infrared (FT-IR) spectroscopy, scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) analyses of the catalyst before and after the reaction, revealing the cause of catalyst deactivation.
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Affiliation(s)
- Liying Jiang
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
| | - Guofeng Nie
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Runye Zhu
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Jiade Wang
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Jianmeng Chen
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
| | - Yubo Mao
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Zhuowei Cheng
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Willam A Anderson
- Department of Chemical Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo N2L 3G1, Ontario, Canada
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Kovacevic G, Sabljic A. Atmospheric oxidation of halogenated aromatics: comparative analysis of reaction mechanisms and reaction kinetics. Environ Sci Process Impacts 2017; 19:357-369. [PMID: 28002503 DOI: 10.1039/c6em00577b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Atmospheric transport is the major route for global distribution of semi-volatile compounds such as halogenated aromatics as well as their major exposure route for humans. Their major atmospheric removal process is oxidation by hydroxyl radicals. There is very little information on the reaction mechanism or reaction-path dynamics of atmospheric degradation of halogenated benzenes. Furthermore, the measured reaction rate constants are missing for the range of environmentally relevant temperatures, i.e. 230-330 K. A series of recent theoretical studies have provided those valuable missing information for fluorobenzene, chlorobenzene, hexafluorobenzene and hexachlorobenzene. Their comparative analysis has provided additional and more general insight into the mechanism of those important tropospheric degradation processes as well as into the mobility, transport and atmospheric fate of halogenated aromatic systems. It was demonstrated for the first time that the addition of hydroxyl radicals to monohalogenated as well as to perhalogenated benzenes proceeds indirectly, via a prereaction complex and its formation and dynamics have been characterized including the respective transition-state. However, in fluorobenzene and chlorobenzene reactions hydroxyl radical hydrogen is pointing approximately to the center of the aromatic ring while in the case of hexafluorobenzene and hexachlorobenzene, unexpectedly, the oxygen is directed towards the center of the aromatic ring. The reliable rate constants are now available for all environmentally relevant temperatures for the tropospheric oxidation of fluorobenzene, chlorobenzene, hexafluorobenzene and hexachlorobenzene while pentachlorophenol, a well-known organic micropollutant, seems to be a major stable product of tropospheric oxidation of hexachlorobenzene. Their calculated tropospheric lifetimes show that fluorobenzene and chlorobenzene are easily removed from the atmosphere and do not have long-range transport potential while hexafluorobenzene seems to be a potential POP chemical and hexachlorobenzene is clearly a typical persistent organic pollutant.
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Affiliation(s)
- Goran Kovacevic
- Rudjer Boskovic Institute, Division of Physical Chemistry, POB 180, HR-10002 Zagreb, Republic of Croatia.
| | - Aleksandar Sabljic
- Rudjer Boskovic Institute, Division of Physical Chemistry, POB 180, HR-10002 Zagreb, Republic of Croatia.
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Raut SS, Kamble SP, Kulkarni PS. Efficacy of zero-valent copper (Cu(0)) nanoparticles and reducing agents for dechlorination of mono chloroaromatics. Chemosphere 2016; 159:359-366. [PMID: 27318451 DOI: 10.1016/j.chemosphere.2016.06.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 06/04/2016] [Accepted: 06/08/2016] [Indexed: 06/06/2023]
Abstract
The zero-valent copper (Cu(0)) nanoparticles were prepared by chemical reduction method. The morphology of nanoparticles was investigated by using X ray diffraction, scanning electron microscopy-energy dispersive X ray, UV-visible spectrophotometer and Brunauer-Emmett-Teller surface area analyser. The Cu(0) nanoparticles along with reducing agents, NaBH4/5% acidified alcohol were used for the dechlorination of chloroaromatics at room temperature. Chlorobenzene (Cl-B), chlorotoluene (Cl-T), chloropyridine (Cl-Py) and chlorobiphenyl (Cl-BPh) were selected as the contaminants. The effect of various operating parameters such as pH, concentration of the catalyst and reducing agent (NaBH4), and recycling of the catalyst on dechlorination were studied. Nearly complete dechlorination of all the chloroaromatics were achieved in the presence of Cu(0) nanoparticles (2.5 g L(-1)) and NaBH4 (1.0 g L(-1)) within 12 h. On the contrary, approximately 70% of dechlorination was observed in the presence of 5% acidified alcohol at similar experimental conditions. The dechlorination mechanism highlighted the importance of Cu(0) nanoparticles as a surface mediator. The kinetics of the dechlorination of chloroaromatics was investigated and compared with chloroaliphatics. The dechlorination rate differed from 0.23 h(-1) (Cl-B) to 0.15 h(-1) (Cl-BPh) in the presence of Cu(0) nanoparticles and NaBH4. The effectiveness of Cu(0) nanoparticles with NaBH4 (1 g L(-1)) and 5% acidified alcohol as electron donors were studied by oxidation-reduction potential and observed to be -1016 mV and -670 mV, respectively. Final products of the dechlorination were benzene, toluene, pyridine and biphenyl, as identified by gas chromatograph mass spectrometer and nuclear magnetic resonance spectroscopy.
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Affiliation(s)
- Sandesh S Raut
- Energy and Environment Laboratory, Department of Applied Chemistry, Defence Institute of Advanced Technology (DU), Ministry of Defence, Pune, 411 025, India
| | - Sanjay P Kamble
- Chemical Engineering and Process Development Division, CSIR-National Chemical Laboratory, Pune, 411 008, India
| | - Prashant S Kulkarni
- Energy and Environment Laboratory, Department of Applied Chemistry, Defence Institute of Advanced Technology (DU), Ministry of Defence, Pune, 411 025, India.
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Han L, Qian L, Yan J, Chen M. Contributions of different biomass components to the sorption of 1,2,4-trichlorobenzene under a series of pyrolytic temperatures. Chemosphere 2016; 156:262-271. [PMID: 27179244 DOI: 10.1016/j.chemosphere.2016.04.031] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 03/31/2016] [Accepted: 04/08/2016] [Indexed: 06/05/2023]
Abstract
In order to investigate contributions of cellulose (CEL), hemicellulose (HEM), lignin (LIG) to the sorption capacity of biochar derived from lignocellulose, the individual component and their artificially modeled biomass mixture (C-H-L) were pyrolyzed under oxygen-limited condition at various pyrolytic temperatures (i.e. 250, 350, 500, 700 °C). The characterization analysis of biochars and sorption batch experiments were carried out. Variations in physiochemical property of different component biochars resulted in discrepancies in their ability to function as sorbents to 1,2,4-trichlorobenzene (1,2,4-TCB). The maximum mass sorption capacity (Qfm) of 1,2,4-TCB was the greatest on CEL biochars ranging from 58.31 to 601.20 mg g(-1), and can be best explained by their huge surface area and micropore volume. Hydrophobic partitioning-sorption into 'soft' amorphous alkyl carbon may account for the second greatest Qfm (45.09-56.57 mg g(-1)) on HEM biochars under low pyrolytic temperatures (250-350 °C) with the lowest surface area. LIG biochars with more compact and smooth aromatic structure surface may undergo a surface monolayer specific adsorption. The Qfm (87.86-196.53 mg g(-1)) on C-H-L biochars were largely dependent on CEL and HEM components for their outstanding sorption capacity and higher content in biomass. Therefore, the results highlighted the importance of CEL and HEM components for 1,2,4-TCB sorption to biochar.
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Affiliation(s)
- Lu Han
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Linbo Qian
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Jingchun Yan
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Mengfang Chen
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
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Cheng Z, Gu Z, Chen J, Yu J, Zhou L. Synthesis, characterization, and photocatalytic activity of porous La-N-co-doped TiO2 nanotubes for gaseous chlorobenzene oxidation. J Environ Sci (China) 2016; 46:203-213. [PMID: 27521952 DOI: 10.1016/j.jes.2015.09.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 09/02/2015] [Accepted: 09/08/2015] [Indexed: 06/06/2023]
Abstract
The photocatalytic oxidation of gaseous chlorobenzene (CB) by the 365nm-induced photocatalyst La/N-TiO2, synthesized via a sol-gel and hydrothermal method, was evaluated. Response surface methodology (RSM) was used to model and optimize the conditions for synthesis of the photocatalyst. The optimal photocatalyst was 1.2La/0.5N-TiO2 (0.5) and the effects of La/N on crystalline structure, particle morphology, surface element content, and other structural characteristics were investigated by XRD (X-ray diffraction), TEM (Transmission Electron Microscopy), FTIR (Fourier transform infrared spectroscopy), UV-vis (Ultraviolet-visible spectroscopy), and BET (Brunauer Emmett Teller). Greater surface area and smaller particle size were produced with the co-doped TiO2 nanotubes than with reference TiO2. The removal of CB was effective when performed using the synthesized photocatalyst, though it was less efficient at higher initial CB concentrations. Various modified Langmuir-Hinshelwood kinetic models involving the adsorption of chlorobenzene and water on different active sites were evaluated. Fitting results suggested that competitive adsorption caused by water molecules could not be neglected, especially for environments with high relative humidity. The reaction intermediates found after GC-MS (Gas chromatography-mass spectrometry) analysis indicated that most were soluble, low-toxicity, or both. The results demonstrated that the prepared photocatalyst had high activity for VOC (volatile organic compounds) conversion and may be used as a pretreatment prior to biopurification.
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Affiliation(s)
- Zhuowei Cheng
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Zhiqi Gu
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Jianmeng Chen
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China.
| | - Jianming Yu
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
| | - Lingjun Zhou
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310014, China
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Zhang S, Lin D, Wu F. The effect of natural organic matter on bioaccumulation and toxicity of chlorobenzenes to green algae. J Hazard Mater 2016; 311:186-193. [PMID: 26989981 DOI: 10.1016/j.jhazmat.2016.03.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 02/29/2016] [Accepted: 03/05/2016] [Indexed: 06/05/2023]
Abstract
The effect of natural organic matter (NOM) on toxicity and bioavailability of hydrophobic organic contaminants (HOCs) to aquatic organisms has been investigated with conflicting results and undefined mechanisms, and few studies have been conducted on volatile HOCs. In this study, six volatile chlorobenzenes (CBs) with 1-6 chlorine substitutions were investigated for their bioaccumulation in an acute toxicity to a green alga (Chlorella pyrenoidosa) in the presence/absence of Suwannee River NOM (SRNOM). The fluorescence quenching efficiency of SRNOM increased as the number of chlorine substitutions of CBs increased. SRNOM increased the cell-surface hydrophobicity of algae and decreased the release rates of algae-accumulated CBs, thus increasing the concentration factor (CF) and accumulation of the CBs in the algae. SRNOM increased the toxicity of monochlorobenzene and 1,2-dichlorobenzene, decreased the toxicity of pentachlorobenzene and hexachlorobenzene, and had no significant effect on the toxicity of 1,2,3-trichlorobenzene and 1,2,3,4-tetrachlorobenzene. Relationships between the 96 h CF/IC50 (i.e., the CB concentration leading to a 50% algal growth reduction compared with the control) and physicochemical properties of CBs with/without SRNOM were established, providing reasonable explanations for the experimental results. These findings will help with the accurate assessment of ecological risks of organic pollutants in the presence of NOM.
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Affiliation(s)
- Shuai Zhang
- College of Environment, Hohai University, Nanjing 210098, China; Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
| | - Daohui Lin
- Department of Environmental Science, Zhejiang University, Hangzhou 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou 310058, China.
| | - Fengchang Wu
- College of Environment, Hohai University, Nanjing 210098, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
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Chen Y, Wu Q, Liu K. Dual degradation of gaseous 1,2-dichlorobenzene and PCDD/Fs using Ce doped VxOy/TiO2 immobilized on cordierite. Chemosphere 2016; 154:472-481. [PMID: 27085061 DOI: 10.1016/j.chemosphere.2016.04.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 03/05/2016] [Accepted: 04/04/2016] [Indexed: 06/05/2023]
Abstract
The photocatalytic film Ce doped VxOy/TiO2 was loaded on cordierite honeycomb (CHC), and this composite was prepared by sol-gel and dipping method, with Ce, oxides of V and TiO2 as dopant and key substances, respectively. Using gaseous 1,2-dichlorobenzene to replace dioxin as target pollutant, dual degradation experiments at 140-280 °C were carried out (thermal decomposition and photodegradation), and the effects of preparation conditions on catalytic activity were investigated: doping amount of Ce, dipping time in the gel, the concentration of ammonium metavanadate (NH4VO3) solution, dipping time in NH4VO3 solution, sintering temperature. The gaseous samples were taken before and after the reactor and analyzed by gas chromatography. According to the results, the optimal preparation conditions were determined, and the corresponding removal rate was above 95% after 90 min of degradation at 280 °C. The composite was examined by ultrasonic to analyze the adhesive strength between the film and CHC, and further characterized by XRD and SEM. Furthermore, flue gas from waste incinerator was chosen as target pollutant, which contained PCDD/Fs, the industrial sidestream degradation experiment was carried out and showed excellent removal efficiency of the composite, the removal rate of PCDD/Fs reached ca. 90% after 90 min of degradation.
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Affiliation(s)
- Yan Chen
- School of Materials and Metallurgy, Northeastern University, Shenyang 110819, PR China
| | - Qiong Wu
- School of Materials and Metallurgy, Northeastern University, Shenyang 110819, PR China
| | - Kuiren Liu
- School of Materials and Metallurgy, Northeastern University, Shenyang 110819, PR China.
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Yu Y, Jung HJ, Je M, Choi HC, Choi MY. Enhanced dechlorination of m-DCB using iron@graphite/palladium (Fe@C/Pd) nanoparticles produced by pulsed laser ablation in liquid. Chemosphere 2016; 155:250-256. [PMID: 27129061 DOI: 10.1016/j.chemosphere.2016.04.048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 04/12/2016] [Accepted: 04/13/2016] [Indexed: 06/05/2023]
Abstract
In this work, the zero valent Fe (ZVI) and graphite-encapsulated Fe (Fe@C) nanoparticles (NPs) were easily and selectively prepared by a pulsed laser ablation (PLA) method in an aqueous sodium borohydride solution and ascorbic acid dissolved in methanol, respectively. Here, the Fe@C NPs were uniquely synthesized by PLA in methanol, where the solvent is used as both a carbon source for the graphitic layers and solvent, which is very unique. Furthermore, Pd NPs were loaded onto the surface of the Fe@C NPs to prepare bimetallic (Fe@C/Pd) NPs for the enhancement of the degradation efficiency of m-dichlorobenzene (m-DCB). The morphology, crystallinity, and surface composition of the prepared NPs were carefully characterized by high-resolution transmission electron microscopy (HRTEM), energy dispersive x-ray spectrometer (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The degradation rate of m-DCB using single (Fe and Pd) or bimetallic (Fe/Pd and Fe@C/Pd) NPs were compared by using gas chromatography. Among these NPs produced in this work, the Fe@C/Pd NPs with 1.71 wt % of Pd showed an excellent dechlorination efficiency for m-DCB with 100% degradation within 75 min. The graphitic layer on the Fe NPs played as not only an oxidation resistant for the Fe NPs to surroundings, but also a supporter of the Pd NPs for the enhanced degradation efficiency of m-DCB.
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Affiliation(s)
- Yiseul Yu
- Department of Chemistry (BK21 PLUS) and Research Institute of Natural Science, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Hyeon Jin Jung
- Department of Chemistry (BK21 PLUS) and Research Institute of Natural Science, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Mingyu Je
- Department of Chemistry (BK21 PLUS) and Research Institute of Natural Science, Gyeongsang National University, Jinju, 660-701, Republic of Korea
| | - Hyun Chul Choi
- Department of Chemistry, Chonnam National University, Gwangju, 500-757, Republic of Korea.
| | - Myong Yong Choi
- Department of Chemistry (BK21 PLUS) and Research Institute of Natural Science, Gyeongsang National University, Jinju, 660-701, Republic of Korea.
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He F, Chen C, Liu S. Effect of Manganese Additive on the Improvement of Low-Temperature Catalytic Activity of VO(x)-WO(x)/TiO2 Nanoparticles for Chlorobenzene Combustion. J Nanosci Nanotechnol 2016; 16:6265-6270. [PMID: 27427700 DOI: 10.1166/jnn.2016.12103] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this study, V-W/TiO2, Mn-V-W/TiO2 and Mn-W/TiO2 nanoparticles were prepared by homogeneous precipitation method and investigated for the catalytic combustion of chlorobenzene (CB), which was used as a model compound of chlorinated volatile organic compounds (CVOCs). The samples were characterized by X-ray diffraction (XRD), nitrogen adsorption-desorption, transmission electron microscope (TEM) and hydrogen temperature-programed reduction (H2-TPR). The average size of the nanoparticles was -20 nm. Manganese species were evenly distributed on the surface of the V-W/TiO2 catalyst, and a small amount of manganese addition did not affect the crystal form, crystallinity and morphology of the V-W/TiO2 catalyst. In addition, low-temperature catalytic activity of V-W/TiO2 catalysts could be effectively improved. When the molar ratio of Mn/(Mn + V) was 0.25 or 0.4, the catalyst displayed the highest low-temperature activity. This was possibly due to Mn (VO3)x formed by the reaction of manganese and vanadium species. Meanwhile, we also found that the addition of oxalic acid was benefit to the improvement of the catalytic activities. When manganese content was high, such as Mn (0.75) VW/Ti, the catalyst activity declined seriously, and the reason was also discussed.
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Kang H, Ito E, Hayashi T, Hara M, Noh J. Effect of Solution Concentration on the Formation of Ordered Domains in Pentachlorobenzenethiol Self-Assembled Monolayers on Au(111). J Nanosci Nanotechnol 2016; 16:6360-6363. [PMID: 27427718 DOI: 10.1166/jnn.2016.12115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The surface structures of self-assembled monolayers (SAMs) formed by the adsorption of pentachlorobenzenethiol (PCBT) molecules on Au(111) as a function of solution concentration were examined by means of scanning tunneling microscopy (STM) to understand the effect of concentration on the formation of ordered domains. STM imaging revealed that PCBT SAMs formed in a 0.01 or 1 mM ethanol solution at room temperature for 20 min contained small ordered domains in the range of several to 20 nm2 and disordered phases, while PCBT SAMs formed in a 0.1 mM ethanol solution were composed of long-range ordered domains in the range of 20 to 50 nm2, which can be assigned as a (4 x √3)R45 degrees packing structure. Interestingly, the bright aggregated domains stacked by π-π interactions between PCBT rings were usually observed around boundary regions of ordered domains. In addition, X-ray photoelectron spectroscopy measurements revealed that ordered PCBT SAMs on Au(111) were formed via the chemical interactions between the sulfur atom of PCBT and gold surface. Our results obtained here will be very useful in understanding the formation and structure of PCBT SAMs on gold surfaces.
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Li Y, Guo Y, Zhu T, Ding S. Adsorption and desorption of SO2, NO and chlorobenzene on activated carbon. J Environ Sci (China) 2016; 43:128-135. [PMID: 27155417 DOI: 10.1016/j.jes.2015.08.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/23/2015] [Accepted: 08/26/2015] [Indexed: 05/12/2023]
Abstract
Activated carbon (AC) is very effective for multi-pollutant removal; however, the complicated components in flue gas can influence each other's adsorption. A series of adsorption experiments for multicomponents, including SO2, NO, chlorobenzene and H2O, on AC were performed in a fixed-bed reactor. For single-component adsorption, the adsorption amount for chlorobenzene was larger than for SO2 and NO on the AC. In the multi-component atmosphere, the adsorption amount decreased by 27.6% for chlorobenzene and decreased by 95.6% for NO, whereas it increased by a factor of two for SO2, demonstrating that a complex atmosphere is unfavorable for chlorobenzene adsorption and inhibits NO adsorption. In contrast, it is very beneficial for SO2 adsorption. The temperature-programmed desorption (TPD) results indicated that the binding strength between the gas adsorbates and the AC follows the order of SO2>chlorobenzene > NO. The adsorption amount is independent of the binding strength. The presence of H2O enhanced the component effects, while it weakened the binding force between the gas adsorbates and the AC. AC oxygen functional groups were analyzed using TPD and X-ray photoelectron spectroscopy (XPS) measurements. The results reveal the reason why the chlorobenzene adsorption is less affected by the presence of other components. Lactone groups partly transform into carbonyl and quinone groups after chlorobenzene desorption. The chlorobenzene adsorption increases the number of C=O groups, which explains the positive effect of chlorobenzene on SO2 adsorption and the strong NO adsorption.
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Affiliation(s)
- Yuran Li
- Beijing Engineering Research Center of Process Pollution Control, National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Yangyang Guo
- Beijing Engineering Research Center of Process Pollution Control, National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Tingyu Zhu
- Beijing Engineering Research Center of Process Pollution Control, National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
| | - Song Ding
- Beijing Engineering Research Center of Process Pollution Control, National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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Kauppila TJ, Haack A, Kroll K, Kersten H, Benter T. Nucleophilic Aromatic Substitution Between Halogenated Benzene Dopants and Nucleophiles in Atmospheric Pressure Photoionization. J Am Soc Mass Spectrom 2016; 27:422-431. [PMID: 26637323 DOI: 10.1007/s13361-015-1315-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 11/12/2015] [Accepted: 11/24/2015] [Indexed: 06/05/2023]
Abstract
In a preceding work with dopant assisted-atmospheric pressure photoionization (DA-APPI), an abundant ion at [M + 77](+) was observed in the spectra of pyridine and quinoline with chlorobenzene dopant. This contribution aims to reveal the identity and route of formation of this species, and to systematically investigate structurally related analytes and dopants. Compounds containing N-, O-, and S-lone pairs were investigated with APPI in the presence of fluoro-, chloro-, bromo-, and iodobenzene dopants. Computational calculations on a density functional theory (DFT) level were carried out to study the reaction mechanism for pyridine and the different halobenzenes. The experimental and computational results indicated that the [M + 77](+) ion was formed by nucleophilic aromatic ipso-substitution between the halobenzene radical cation and nucleophilic analytes. The reaction was most efficient for N-heteroaromatic compounds, and it was weakened by sterical effects and enhanced by resonance stabilization. The reaction was most efficient with chloro-, bromo-, and iodobenzenes, whereas with fluorobenzene the reaction was scarcely observed. The calculated Gibbs free energies for the reaction between pyridine and the halobenzenes were shown to increase in the order I < Br < Cl < F. The reaction was found endergonic for fluorobenzene due to the strong C-F bonding, and exergonic for the other halobenzenes. For fluoro- and chlorobenzenes the reaction was shown to proceed through an intermediate state corresponding to [M + dopant](+), which was highly stable for fluorobenzene. For the bulkier bromine and iodine, this intermediate did not exist, but the halogens were shown to detach already during the approach by the nucleophile.
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Affiliation(s)
- Tiina J Kauppila
- Faculty of Pharmacy, University of Helsinki, Helsinki, 00014, Finland.
| | - Alexander Haack
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Wuppertal, 42119, Germany
| | - Kai Kroll
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Wuppertal, 42119, Germany
| | - Hendrik Kersten
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Wuppertal, 42119, Germany
| | - Thorsten Benter
- Department of Physical and Theoretical Chemistry, University of Wuppertal, Wuppertal, 42119, Germany
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Wang QL, Huang QX, Wu HF, Lu SY, Wu HL, Li XD, Yan JH. Catalytic decomposition of gaseous 1,2-dichlorobenzene over CuOx/TiO₂ and CuOx/TiO₂-CNTs catalysts: Mechanism and PCDD/Fs formation. Chemosphere 2016; 144:2343-2350. [PMID: 26606189 DOI: 10.1016/j.chemosphere.2015.10.097] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 08/17/2015] [Accepted: 10/22/2015] [Indexed: 06/05/2023]
Abstract
Gaseous 1,2-dichlorobenzene (1,2-DCBz) was catalytically decomposed in a fixed-bed catalytic reactor using composite copper-based titanium oxide (CuOx/TiO2) catalysts with different copper ratios. Carbon nanotubes (CNTs) were introduced to produce novel CuOx/TiO2-CNTs catalysts by the sol-gel method. The catalytic performances of CuOx/TiO2 and CuOx/TiO2-CNTs on 1,2-DCBz oxidative destruction under different temperatures (150-350 °C) were experimentally examined and the correlation between catalyst structure and catalytic activity was characterized and the role of oxygen in catalytic reaction was discussed. Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) generation during 1,2-DCBz catalytic oxidation by CuOx/TiO2-CNTs composite catalyst was also examined. Results indicate that the 1,2-DCBz destruction/removal efficiencies of CuOx (4 wt%)/TiO2 catalyst at 150 °C and 350 °C with a GHSV of 3400 h(-1) are 59% and 94% respectively and low-temperature (150 °C) catalytic activity of CuOx/TiO2 on 1,2-DCBz oxidation can be improved from 59 to 77% when CNTs are introduced. Furthermore, oxygen either in catalyst or from reaction atmosphere is indispensible in reaction. The former is offered to activate and oxidize the 1,2-DCBz adsorbed on catalyst, thus can be generally consumed during reaction and the oxygen content in catalyst is observed lost from 39.9 to 35.0 wt% after reacting under inert atmosphere; the latter may replenish the vacancy in catalyst created by the consumed oxygen thus extends the catalyst life and raises the destruction/removal efficiency. The introduction of CNTs also increases the Cu(2+)/Cu(+) ratio, chemisorbed oxygen concentration and surface lattice oxygen binding energy which are closely related with catalytic activity. PCDD/Fs is confirmed to be formed when 1,2-DCBz catalytically oxidized by CuOx/TiO2-CNTs composite catalyst with sufficient oxygen (21%), proper temperature (350 °C) and high concentration of 1,2-DCBz feed (120 ppm).
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Affiliation(s)
- Qiu-lin Wang
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China; School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China
| | - Qun-xing Huang
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China.
| | - Hui-fan Wu
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
| | - Sheng-yong Lu
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
| | - Hai-long Wu
- Zhoushan Environmental Protection Bureau, Zhoushan 316000, China
| | - Xiao-dong Li
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
| | - Jian-hua Yan
- State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering of Zhejiang University, Hangzhou 310027, China
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Ungvarská Maľučká L, Vilková M, Kožíšek J, Imrich J. Strong deshielding in aromatic isoxazolines. Magn Reson Chem 2016; 54:17-27. [PMID: 26365723 DOI: 10.1002/mrc.4308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 07/01/2015] [Accepted: 07/06/2015] [Indexed: 06/05/2023]
Abstract
Very strong proton deshielding was found in di/tri-aromatic isoxazoline regioisomers prepared from acridin-4-yl dipolarophiles and stable benzonitrile oxides (BNO). Three alkenes, (acridin-4-yl)-CH=CH-R (R = COOCH3, Ph, and CONH2), reacted with three BNO dipoles (2,4,6-trimethoxy, 2,4,6-trimethyl, 2,6-dichloro) to give pairs of target isoxazolines with acridine bound to C-4 or C-5 carbon of the isoxazoline (denoted as 4-Acr or 5-Acr). Regioselectivity was dependent on both the dipolarophile and dipole character. The ester and amide dipolarophile displayed variable regioselectivity in cycloadditions whereas the styrene one afforded prevailing 4-Acr regioisomers. 2,4,6-Trimethoxy-BNO was most prone to form 5-Acr isoxazolines while mesitonitrile oxide gave major 4-Acr isoxazolines. Basic hydrolysis of the amide cycloadduct led to an unexpected isoxazolone product. The structure of the target compounds was studied by NMR, MS, and X-ray crystallography.
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Affiliation(s)
- Lucia Ungvarská Maľučká
- P. J. Šafárik University, Faculty of Science, Institute of Chemistry, NMR Laboratory, Moyzesova 11, 040 01, Košice, Slovakia
| | - Mária Vilková
- P. J. Šafárik University, Faculty of Science, Institute of Chemistry, NMR Laboratory, Moyzesova 11, 040 01, Košice, Slovakia
| | - Jozef Kožíšek
- Slovak Technical University, Faculty of Chemical and Food Technology, Department of Physical Chemistry, Radlinského 9, 812 37, Bratislava, Slovakia
| | - Ján Imrich
- P. J. Šafárik University, Faculty of Science, Institute of Chemistry, NMR Laboratory, Moyzesova 11, 040 01, Košice, Slovakia
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Cecilia JA, Infantes-Molina A, Rodríguez-Castellón E. Hydrodechlorination of polychlorinated molecules using transition metal phosphide catalysts. J Hazard Mater 2015; 296:112-119. [PMID: 25913677 DOI: 10.1016/j.jhazmat.2015.04.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 03/08/2015] [Accepted: 04/08/2015] [Indexed: 06/04/2023]
Abstract
Ni2P and CoP catalysts (5 wt.% of metal) supported on a commercial SiO2 were tested in the gas phase catalytic hydrodechlorination (HDCl) of mono (chlorobenzene-ClB) and polychlorobenzenes (PCBs) (1,2- dichlorobenzene (1,2-DClB), 1,3-dichlorobenzene (1,3-DClB), 1,4-dichlorobenzene (1,4-DClB), and 1,2,4-trichlorobenzene (1,2,4-TClB)) at atmospheric pressure. It was investigated how the number and position of chlorine atoms in the molecule influence the HDCl activity. The prepared catalysts were characterized by X-ray diffraction (XRD), CO chemisorption, N2 adsorption-desorption at -196°C, and X-ray photoelectron spectroscopy (XPS). Characterization results indicated better active phase dispersion and greater amount of P on the Ni2P catalyst surface. Catalytic results showed that the Ni2P was more active and stable in this type of reactions. The hydrodechlorination activity decreased by increasing the number of chlorine atoms in the molecule and chlorine substituents in close proximity. The observed trend in the HDCl activity was: ClB>1,4-DClB>1,3-DClB>1,2-DClB>1,2,4-TClB. The exception was the catalytic response after 24h on stream observed for the Ni2P in the HDCl reaction of 1,2,4-TClB, which was equal to that observed for the 1,4-DClB molecule, and also yielding benzene as the main reaction product.
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Affiliation(s)
- J A Cecilia
- Departamento de Química Inorgánica, Cristalografía y Mineralogía, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos, 29071 Málaga, Spain
| | - A Infantes-Molina
- Departamento de Química Inorgánica, Cristalografía y Mineralogía, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos, 29071 Málaga, Spain.
| | - E Rodríguez-Castellón
- Departamento de Química Inorgánica, Cristalografía y Mineralogía, Facultad de Ciencias, Universidad de Málaga, Campus de Teatinos, 29071 Málaga, Spain
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Chiou CT, Cheng J, Hung WN, Chen B, Lin TF. Resolution of Adsorption and Partition Components of Organic Compounds on Black Carbons. Environ Sci Technol 2015; 49:9116-9123. [PMID: 26114972 DOI: 10.1021/acs.est.5b01292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Black carbons (BCs) may sequester non-ionic organic compounds by adsorption and/or partition to varying extents. Up to now, no experimental method has been developed to accurately resolve the combined adsorption and partition capacity of a compound on a BC. In this study, a unique "adsorptive displacement method" is introduced to reliably resolve the adsorption and partition components for a solute-BC system. It estimates the solute adsorption on a BC by the use of an adsorptive displacer to displace the adsorbed target solute into the solution phase. The method is validated by tests with uses of activated carbon as the model carbonaceous adsorbent, soil organic matter as the model carbonaceous partition phase, o-xylene and 1,2,3-trichlorobenzene as the reference solutes, and p-nitrophenol as the adsorptive displacer. Thereafter, the adsorption-partition resolution was completed for the two solutes on selected model BCs: four biochars and two National Institute of Standards and Technology (NIST) standard soots (SRM-2975 and SRM-1650b). The adsorption and partition components resolved for selected solutes with given BCs and their dependences upon solute properties enable one to cross-check the sorption data of other solutes on the same BCs. The resolved components also provide a theoretical basis for exploring the potential modes and extents of different solute uptakes by given BCs in natural systems.
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Affiliation(s)
- Cary T Chiou
- †Department of Environmental Engineering and Sustainable Environment Research Center, National Cheng Kung University, Tainan 70701, Taiwan
- ‡United States Geological Survey, Denver Federal Center, Denver, Colorado 80225, United States
| | - Jianzhong Cheng
- §State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang, Guizhou 550081, People's Republic of China
| | - Wei-Nung Hung
- ∥Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu 30011, Taiwan
| | - Baoliang Chen
- ⊥Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang 310058, People's Republic of China
| | - Tsair-Fuh Lin
- †Department of Environmental Engineering and Sustainable Environment Research Center, National Cheng Kung University, Tainan 70701, Taiwan
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Abstract
A large industrial water resource recovery facility needed to significantly reduce the amount of 1,2-dichlorobenzene (ODCB) entering its biological treatment units. Numerous Advanced Oxidation Processes (AOPs) were considered based on literature and industry reports. Many AOPs appear to be incompatible with some of the native species present in groundwater or wastewater matrices. Iron, in particular, is often viewed as a nuisance increasing the complexity of the overall treatment scheme. The approach used in the current study was to incorporate the new AOP into the existing groundwater matrix and facilities as much as possible. To that end, native iron was exploited as the reaction catalyst, an acid was selected to fit with current macro nutrient needs of the biotreatment units, and the reactor was designed to require minimum modification of the existing facilities. The "green chemical" (Noyori, 2003) treatment process selected was demonstrated at full-scale, achieving good agreement with the results of prior laboratory studies. Up to eighty percent destruction of ODCB was demonstrated in a new pretreatment unit whose effluent fit seamlessly with the existing bioreactors.
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Affiliation(s)
- Mark D Richmond
- DuPont Chambers Works, Building 1244, Route 130, Deepwater, New Jersey, 08023, USA
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Netskina OV, Tayban ES, Moiseenko AP, Komova OV, Mukha SA, Simagina VI. Removal of 1,2-dichlorobenzene from water emulsion using adsorbent catalysts and its regeneration. J Hazard Mater 2015; 285:84-93. [PMID: 25497020 DOI: 10.1016/j.jhazmat.2014.10.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 09/27/2014] [Accepted: 10/04/2014] [Indexed: 06/04/2023]
Abstract
Purification of emulsions of 1,2-dichlorobenzene (1,2-DCB) by carbon-based adsorbent catalysts has been studied. The cycle of purification includes: (1) adsorption of 1,2-DCB from the aqueous phase and (II) reductive regeneration by hydrodechlorination of the adsorbed 1,2-DCB by molecular hydrogen in the liquid phase. 1,2-DCB adsorption from aqueous solutions has been found to proceed by the mechanism of volume filling of pores. The rate of hydrodechlorination was shown to correlate with the particle size of the active component: the finer the particles, the higher the activity of the adsorbent catalyst. Pd/FAS with an average Pd particle size of 2.8 nm was found to be the most efficient catalyst.
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Affiliation(s)
- O V Netskina
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia.
| | - E S Tayban
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| | - A P Moiseenko
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia; Department of Chemistry and Chemical Technology, Novosibirsk State Technical University, Pr. Karla Marksa 20, Novosibirsk 630092, Russia
| | - O V Komova
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| | - S A Mukha
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| | - V I Simagina
- Laboratory of Hydride Investigation, Boreskov Institute of Catalysis SB RAS, Pr. Akademika Lavrentieva 5, Novosibirsk 630090, Russia; Siberian Branch of the Russian Presidential Academy of National Economy and Public Administration, Nizhegorodskaya 6, Novosibirsk 630102, Russia
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Abd El-Kader FH, Hakeem NA, Elashmawi IS, Menazea AA. Synthesis and characterization of PVK/AgNPs nanocomposites prepared by laser ablation. Spectrochim Acta A Mol Biomol Spectrosc 2015; 138:331-339. [PMID: 25506650 DOI: 10.1016/j.saa.2014.11.083] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Revised: 11/09/2014] [Accepted: 11/23/2014] [Indexed: 06/04/2023]
Abstract
Nanocomposites of Poly (n-vinylcarbazole) PVK/Ag nanoparticles were prepared by laser ablation of a silver plate in aqueous solution of chlorobenzene. The influences of laser parameters such as; time of irradiation, source power and wavelength (photon energy) on structural, morphological and optical properties have been investigated using X-ray diffraction (XRD), Transmission electron microscopy (TEM), Ultraviolet-visible (UV-Vis) and Photoluminescence (PL). A correlation between the investigated properties has been discussed. XRD, TEM and PL indicated that the complexation between AgNPs and PVK in the composite system is possible. Only the reflection peak at 2θ=38° of AgNPs appeared in the composite nanoparticles while the other reflection peaks were destroyed. The nanoparticles shape and size distribution were evaluated from TEM images. TEM analysis revealed a lower average particle size at long laser irradiation time 40min and short laser wavelength 532nm together with high laser power 570mW. From UV-Visible spectra the values of absorption coefficient, absorption edge and energy tail were calculated. The reduction of band tail value with increasing the laser ablation parameters confirms the decrease of the disorder in such composite system. The PL and UV-Vis. spectra confirm that nanocomposite samples showed quantum confinement effect.
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Affiliation(s)
- F H Abd El-Kader
- Physics Department, Faculty of Science, Cairo University, Giza, Egypt
| | - N A Hakeem
- Spectroscopy Department, Physics Division, National Research Centre, Giza, Egypt
| | - I S Elashmawi
- Spectroscopy Department, Physics Division, National Research Centre, Giza, Egypt; Physics Department, Faculty of Science, Taibah University, Al-Ula, Madina, Saudi Arabia.
| | - A A Menazea
- Spectroscopy Department, Physics Division, National Research Centre, Giza, Egypt
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Jiang LY, Cao SL, Zhu RY, Chen JM, Su F. [Analysis of characteristics and products of chlorobenzene degradation with dielectric barrier discharge]. Huan Jing Ke Xue 2015; 36:831-838. [PMID: 25929048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
For non-biodegradable volatile organic compounds (VOCs) with low water solubility, the tradition biological method can not achieve a satisfactory removal efficiency, so development of high efficiency pre-treatment technology is a hot issue of research. In this experiment, using poor biodegradable chlorobenzene as the target pollutant and dielectric barrier discharge (DBD) non-thermal plasma as the pretreatment technology for biotrickling filter (BTF) , the effect of DBD on the degradation of chlorobenzene was studied by adjusting the technical parameters of DBD. The effects of the inlet concentration, residence time, humidity and peak voltage on decomposition efficiency were investigated and the decomposition products of chlorobenzene were analyzed. Experimental results showed that DBD could effectively remove waste gaseous chlorobenzene, the removal rate of chlorobenzene increased with the increasing peak voltage. When the peak voltage was ≥ 12kV, less effect of residence time on the degradation of chlorobenzene was found. The optimal humidity range of degradation chlorobenzene was 65% - 75%. Through the analysis of degradation products, the species and concentrations of degradation products increased with the increase of discharge voltage. The products were mainly consisted of organic acids and chlorinated hydrocarbons. The water solubility of degradation products was preferable. Furthermore, with the increase of discharge voltage, the biodegradability of degradation products became higher and higher and the biological toxicity was reduced. It had a promoting effect on the degradation of chlorobenzene when the voltage reached 20 kV. Meanwhile, the O3 concentration increased with the increasing discharge voltage and also enhanced with the rising humidity under the same voltage.
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