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Jin M, Sun M, Liu J, Dong C, Xue J. Influence of operating parameters on the yield of micro-plastics from plastics incineration. Sci Total Environ 2024; 912:169347. [PMID: 38104822 DOI: 10.1016/j.scitotenv.2023.169347] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Revised: 11/20/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
Plastics account for a large proportion of domestic waste. However, micro-plastics will be produced after the plastic is incinerated. The purpose of this study is to find out the change rule of micro-plastics produced during incineration under different conditions. Combining micro-FTIR and PCA algorithm is a good tool to identify the micro-plastics. The PE, PP and PVC micro-plastics are distinguished using PCA-FTIR spectra. The results show different incineration conditions significantly affect the output of micro-plastics. The yield of micro-plastics increases with increasing temperature for both PP and PVC. And the yield of micro-plastics decreases with the increase in flow rate. The maximum amount of micro-plastics is produced by PE, which is 6.62 × 103 after 1 g PE incineration. The yield of micro-plastics in the co-incineration of PE and PP, as well as PE and PVC, significantly increased to 1.42 and 1.89 times of the calculated values, respectively. The nano-particles are also observed. The FTIR and EDS results show that the nano-particles are the products of incineration of plastics, including partly CH bond and unburned carbon, tar and ash.
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Affiliation(s)
- Mingnuo Jin
- School of New Energy, North China Electric Power University, No.2 Beinong Road, Beijing 102206, PR China
| | - Mufei Sun
- School of New Energy, North China Electric Power University, No.2 Beinong Road, Beijing 102206, PR China
| | - Jingyi Liu
- School of New Energy, North China Electric Power University, No.2 Beinong Road, Beijing 102206, PR China
| | - Changqing Dong
- School of New Energy, North China Electric Power University, No.2 Beinong Road, Beijing 102206, PR China
| | - Junjie Xue
- School of New Energy, North China Electric Power University, No.2 Beinong Road, Beijing 102206, PR China.
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2
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Zhang W, Xue W, Zhang C, Xiao K. Towards long-term operation of flow-electrode capacitive deionization (FCDI): Optimization of operating parameters and regeneration of flow-electrode. Heliyon 2024; 10:e24940. [PMID: 38312617 PMCID: PMC10834994 DOI: 10.1016/j.heliyon.2024.e24940] [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] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 01/11/2024] [Accepted: 01/17/2024] [Indexed: 02/06/2024] Open
Abstract
This study systematically optimized the key operating parameters and interpreted their effecting mechanisms in a flow-electrode capacitive deionization (FCDI) system. The optimal voltage, activated carbon electrode content, electrolyte concentration, feedwater flowrate, and electrode flowrate for desalinating low salinity feedwater (1.0 g L-1 NaCl) were determined to be 1.8 V, 2.0 wt%, 10.0 g L-1, 80 mL min-1, and 60 mL min-1, respectively. The variations of the above parameters can affect the system conductivity, the thickness and stability of the electric double layers, and/or the degree of concentration polarization, thereby influencing the desalination performance. Moreover, a sensitivity analysis identified the operating voltage as the dominant parameter with the most significant influence on the FCDI system. Subsequently, a long-term operation was carried out under single-pass mode. The results showed that the lab-scale FCDI system was able to constantly maintain the desalination efficiency of 1.0 g L-1 feedwater (NaCl) at 40-60 % for multiple operating cycles. Over 99.8 % of electrode material regeneration and desalination efficiency recovery was able to be obtained during a 60-h operation, demonstrating that the FCDI system showed strong stability and long-term operation potential.
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Affiliation(s)
- Wanni Zhang
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani, 12120, Thailand
| | - Wenchao Xue
- Department of Energy, Environment and Climate Change, School of Environment, Resources and Development, Asian Institute of Technology, P.O. Box 4, Klong Luang, Pathumthani, 12120, Thailand
| | - Chunpeng Zhang
- Key Laboratory of Groundwater Resources and Environment (Ministry of Education), College of New Energy and Environment, Jilin University, Changchun, 130021, China
| | - Kang Xiao
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, China
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Dhara FT, Fayshal MA. Waste Sludge: Entirely Waste or a Sustainable Source of Biocrude? A Review. Appl Biochem Biotechnol 2024:10.1007/s12010-023-04846-7. [PMID: 38236434 DOI: 10.1007/s12010-023-04846-7] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2023] [Indexed: 01/19/2024]
Abstract
Biomass-derived biocrude is gaining greater recognition from people in general as an alternative fuel source to traditional fossil fuels. Worldwide, a great deal of research is being done to develop fuels made from sustainable biomass in order to replace the current conventional energy sources. Waste sludge has been thought of as a viable raw biomass source because of its accessibility, affordability, high lignin content, and higher heating value. Additionally, considering sludge contains a high proportion of moisture and water acts as a catalyst during the hydrothermal liquefaction (HTL) process, it is the best choice for thermochemical conversion. From the ultimate component value ranges obtained from elemental analysis, it can be demonstrated that the C, H, and higher heating value (HHV) of petrocrude are approximately 8.78%, 23.5%, and 10.66% higher than those of biofuel. According to the overall analysis, co-liquefaction of waste vegetable oil and swine manure can result in 87.97% bio-oil at 340 °C. The temperature, retention period, inclusion of catalysts, and use of solvents, however, can all affect this proportion. To support this illustration, it has been assessed from the study that municipal wet sewage sludge can produce an HHV of 28.52 MJ/kg when water is used as the solvent. However, 34.14 MJ/kg, or 16.5% more than the previous one, can be produced for the same amount of biomass, when the mixture of water and methanol serves as the solvents. This review article highlights an array of waste sludge categories, their chemical properties, and their conversion through the HTL process. It also features a Van Krevlen diagram with a graphical representation of essential operating parameters. This review research illustrates one of the best strategies for producing biofuel in which waste sludge can be used as raw material through the HTL conversion process, considering the prospective mass commercial production of biocrude oil.
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Affiliation(s)
- Farin Tasnuva Dhara
- Department of Civil Engineering, Khulna University of Engineering & Technology (KUET), Khulna, 9203, Bangladesh
| | - Md Atik Fayshal
- Department of Civil Engineering, Khulna University of Engineering & Technology (KUET), Khulna, 9203, Bangladesh.
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4
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Zhu S, Zhao B, Zhang H, Su Y. Biomass-based adsorbents for post-combustion CO 2 capture: Preparation, performances, modeling, and assessment. J Environ Manage 2023; 328:117020. [PMID: 36527800 DOI: 10.1016/j.jenvman.2022.117020] [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: 10/12/2022] [Revised: 11/24/2022] [Accepted: 12/10/2022] [Indexed: 06/17/2023]
Abstract
The adsorbents are critical carriers in the process of adsorption-based post-combustion CO2 capture. Biomass-based adsorbents (BAs) are considered to have great potential because of their high efficiency, low cost, and good sustainability. To understand the methods, theories, and technologies of BAs-based CO2 capture, this work analyzes their preparation and activation/modification, influencing factors, mechanisms, thermodynamics/kinetics, regeneration and cycle performances, and the pathway to application. It is found that BAs prepared by pyrolysis, chemical activation, and modification with dual heteroatoms are more conducive to improving adsorption sites. CO2 adsorption capacity positively correlates with elemental C and fixed carbon of feedstocks, but negatively with moisture. The BAs prepared at 550-600 °C have high performance. The specific surface area (SSA) increases as the preparation time increases by 9.4%-93.4%. The adsorption capacity is positively correlated to the SSA (R = 0.880) and microporous volume (R = 0.773). Moreover, it decreases linearly with increasing operating temperature with the slope of -0.6 mmol/(g·°C) but increases exponentially with increasing operating pressure and CO2 concentration with the power of 0.824. The adsorption process includes physical and/or physicochemical adsorption. Freundlich isotherm equation and pseudo-second-order model characterize the adsorption thermodynamics and kinetics more effectively with R2 = 0.985-1.000 and R2 = 0.894-1.000. The quantum chemistry indicates that most BAs modified with non-metallic belong to physisorption. The regeneration of BAs has low energy consumption (<3.44 MJ/kg CO2) and loss rate (<8%). Furthermore, the technical pathway is proposed for application. Finally, the challenges are also presented to facilitate the development of BAs-CO2 capture.
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Affiliation(s)
- Shaoliang Zhu
- School of Energy and Power Engineering, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai, 200093, China
| | - Bingtao Zhao
- School of Energy and Power Engineering, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai, 200093, China.
| | - Haonan Zhang
- School of Energy and Power Engineering, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai, 200093, China
| | - Yaxin Su
- School of Environmental Science and Engineering, Donghua University, 2999 North Renmin Road, Shanghai, 201620, China
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Li C, de Melo Costa Serge N, Nogueira RFP, Chiron S, Goetz V. Peroxydisulfate activation by CuO pellets in a fixed-bed column, operating mode and assessments for antibiotics degradation and urban wastewater disinfection. Environ Sci Pollut Res Int 2022; 29:71709-71720. [PMID: 35599288 DOI: 10.1007/s11356-022-20847-1] [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: 01/31/2022] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
A fixed-bed column packed with copper oxide pellets (FBC-CuO) combined with peroxydisulfate (PDS) as a primary oxidant was assessed as an option for simultaneously wastewater decontamination (antibiotics) and disinfection (bacteria, viruses, and protozoa). Preliminary to these experiments, phenol was used as the target molecule to investigate the working mode of FBC-CuO under various operating conditions, such as varying flow rates, initial persulfate, and phenol concentrations. Then, the removal of a mix of five representative antibiotics (amoxicillin (AMX), cefalexin (CFX), ofloxacin (OFL), sulfamethoxazole (SMX), and clarithromycin (CLA)) in secondary treated urban wastewater (STWW) was evaluated. AMX, CFX, and OFL were effectively removed by simply flowing through the FBC-CuO, and the addition of PDS (500 µM) systematically enhanced the degradation of all targeted antibiotics, which is also the necessary condition for the removal of SMX and CLA. Urban wastewater disinfection was evaluated by monitoring targeted pathogens originally in the STWW. A significant reduction of Escherichia coli, Enterococcus, F-specific RNA bacteriophages was observed after the treatment by FBC-CuO with 500 µM PDS. X-ray diffraction measurement and scanning electron microscopy performed on CuO pellets before and after treatment confirmed that the structure of the catalyst was preserved without any phase segregation. Finally, quantification of Cu(II) at the outlet of FBC-CuO indicate a non-negligible but limited released. All these results underline the potential of the FBC-CuO combined with PDS at the field scale for the degradation of micropollutants and inactivation of pathogens in wastewater.
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Affiliation(s)
- Chan Li
- UMR5151 HydroSciences Montpellier, University of Montpellier, IRD, 15 Ave Charles Flahault, 34093, Montpellier cedex 5, France
| | | | | | - Serge Chiron
- UMR5151 HydroSciences Montpellier, University of Montpellier, IRD, 15 Ave Charles Flahault, 34093, Montpellier cedex 5, France
| | - Vincent Goetz
- PROMES-CNRS UPR 8521, PROcess Material and Solar Energy, Rambla de La Thermodynamique, 66100, Perpignan, France.
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Prasertcharoensuk P, Promtongkaew A, Tawatchai M, Marquez V, Jongsomjit B, Tahir M, Praserthdam S, Praserthdam P. A review on sensitivity of operating parameters on biogas catalysts for selective oxidation of Hydrogen Sulfide to elemental sulfur. Chemosphere 2022; 301:134579. [PMID: 35413367 DOI: 10.1016/j.chemosphere.2022.134579] [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: 02/04/2022] [Revised: 03/24/2022] [Accepted: 04/07/2022] [Indexed: 06/14/2023]
Abstract
Hydrogen sulfide (H2S) is a critical problem for biogas applications, such as electricity and heat generation, or the production of different chemical compounds, due to corrosion and toxic effluent gases. The selective catalytic oxidation of H2S to S is the most promising way to eliminate H2S from biogas due to the lack of effluents, therefore can be considered a green technology. The most extensively used catalysts for H2S selective oxidation can be classified in two groups: metal oxide-based catalysts, including vanadium and iron oxides, and carbon-based catalysts. Numerous studies have been devoted to studying their different catalytic performances. For industrial applications, the most suitable catalysts should be less sensitive to the operating parameters like the temperature, O2/H2S ratio, and H2O content. More specifically, for metal oxides and carbon-based catalysts, the temperature and O2/H2S ratio have a similar effect on the conversion and selectivity, but carbon-based catalysts are less sensitive to water in all operating conditions.
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Affiliation(s)
- Phuet Prasertcharoensuk
- Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Athitaya Promtongkaew
- Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Makamas Tawatchai
- Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Victor Marquez
- Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Bunjerd Jongsomjit
- Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Muhammad Tahir
- Chemical and Petroleum Engineering Department, UAE University, 15551, Al Ain, United Arab Emirates
| | - Supareak Praserthdam
- Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand; High-Performance Computing Unit (CECC-HCU), Centre of Excellence on Catalysis and Catalytic Reaction Engineering (CECC), Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand
| | - Piyasan Praserthdam
- Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok, 10330, Thailand.
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7
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Parker S, Cronshaw M, Grootveld M, George R, Anagnostaki E, Mylona V, Chala M, Walsh L. The influence of delivery power losses and full operating parametry on the effectiveness of diode visible-near infra-red (445-1064 nm) laser therapy in dentistry-a multi-centre investigation. Lasers Med Sci 2022; 37:2249-2257. [PMID: 35028767 DOI: 10.1007/s10103-021-03491-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/06/2021] [Indexed: 12/17/2022]
Abstract
The development of protocols for laser-assisted therapy demands strict compliance with comprehensive operating parametry. The purpose of this investigation was to examine the accuracy of correlation between laser control panel and fibre emission power values in a selection of diode dental lasers. Through retrospective analysis using successive systematic review and meta-analysis, it is clear that there is inconsistency in the details, and possible inaccuracies in laser power applied and associated computed data. Through a multi-centre investigation, 38 semi-conductor ("diode") dental laser units were chosen, with emission wavelengths ranging from 445 to 1064 nm. Each unit had been recently serviced according to manufacturer's recommendations, and delivery fibre assembly checked for patency and correct alignment with the parent laser unit. Subject to the output capacity of each laser, four average power values were chosen using the laser control panel-100 mW, 500 mW, 1.0 W, and 2.0 W. Using a calibrated power meter, the post-fibre emission power value was measured, and a percentage power loss calculated. For each emission, a series of six measurements were made and analysed to investigate sources of power losses along the delivery fibre, and to evaluate the precision of power loss determinations. Statistical analysis of a dataset comprising % deviations from power setting levels was performed using a factorial ANOVA model, and this demonstrated very highly significant differences between devices tested and emission power levels applied (p < 10-142 and < 10-52 respectively). The devices × emission power interaction effect was also markedly significant (p < 10-66), and this confirmed that differences observed in these deviations for each prior power setting parameter were dependent on the device employed for delivery. Power losses were found to be negatively related to power settings applied. Significant differences have emerged to recommend the need to standardize a minimum set of parameters that should form the basis of comparative research into laser-tissue interactions, both in vitro and in vivo.
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Affiliation(s)
- Steven Parker
- Leicester School of Pharmacy, De Montfort University, Leicester, UK.
| | - Mark Cronshaw
- Leicester School of Pharmacy, De Montfort University, Leicester, UK.,School of Dentistry, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK
| | - Martin Grootveld
- Leicester School of Pharmacy, De Montfort University, Leicester, UK
| | - Roy George
- School of Medicine and Dentistry, Griffith University, Brisbane, QLD, Australia
| | | | - Valina Mylona
- Leicester School of Pharmacy, De Montfort University, Leicester, UK
| | - Marianna Chala
- Department of Surgical Sciences and Integrated Diagnostics, University of Genoa, Genoa, Italy
| | - Laurence Walsh
- Emeritus Professor, University of Queensland School of Dentistry, Herston, QLD, Australia
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Geng S, Qin W, Cao W, Wang Y, Ding A, Zhu Y, Fan F, Dou J. Pilot-scale bioaugmentation of polycyclic aromatic hydrocarbon (PAH)-contaminated soil using an indigenous bacterial consortium in soil-slurry bioreactors. Chemosphere 2022; 287:132183. [PMID: 34500332 DOI: 10.1016/j.chemosphere.2021.132183] [Citation(s) in RCA: 3] [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] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 08/08/2021] [Accepted: 09/04/2021] [Indexed: 06/13/2023]
Abstract
Soil-slurry bioreactor based bioremediation of polycyclic aromatic hydrocarbons (PAHs) contaminated soil was studied through laboratory and pilot-scale trials, in which the degradation mechanism was explored. Indigenous PAH-degrading consortium was firstly screened out and it degraded 80.5% of total PAHs in lab-scale bioreactors. Then a pilot-scale trial lasting 410 days was conducted in two bioreactors of 1.5 m3 to examine the operating parameters and validate the optimum running conditions. During the initial 200 days, the crucial running parameters affecting PAH removal were evaluated and selected. Subsequently, an average PAH removal rate of 93.4% was achieved during 15 consecutive batches (210 days) under the optimum running conditions. The kinetic analysis showed that the reactor under optimum conditions achieved the highest PAH degradation rate of 0.1795 day-1 and the shortest half-life of 3.86 days. Notably, efficient mass transfer of PAHs and high biodegradation capability by bioaugmented consortia in soil-slurry bioreactors were two key mechanisms for appreciable PAH removal performance. Under the optimal operating conditions, the degradation rate of low-molecular-weight (LMW) PAHs was significantly higher than high-molecular-weight (HMW) PAHs; when the mass transfer was limited, there was no significant difference between their degradation behaviors. Both microbial co-metabolism and collaborative metabolism might occur when all PAHs demonstrated low degradation rates. The findings provide insightful guidance on the future assessment and remediation practices of PAH-contaminated sites.
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Affiliation(s)
- Shuying Geng
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing, 100875, PR China
| | - Wei Qin
- School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Wei Cao
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing, 100875, PR China
| | - Yingying Wang
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing, 100875, PR China
| | - Aizhong Ding
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing, 100875, PR China
| | - Yi Zhu
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing, 100875, PR China
| | - Fuqiang Fan
- Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai, 519087, PR China.
| | - Junfeng Dou
- Engineering Research Center of Ministry of Education on Groundwater Pollution Control and Remediation, College of Water Sciences, Beijing Normal University, Beijing, 100875, PR China.
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Rodrigues Pinto B, Linares JJ, de Vasconcelos Lanza MR, de Lourdes Souza F. UV-irradiation and BDD-based photoelectrolysis for the treatment of halosulfuron-methyl herbicide. Environ Sci Pollut Res Int 2021; 28:26762-26771. [PMID: 33495947 DOI: 10.1007/s11356-021-12603-8] [Citation(s) in RCA: 2] [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: 10/19/2020] [Accepted: 01/18/2021] [Indexed: 06/12/2023]
Abstract
This paper reports the development of a novel photoelectrochemical (PEC) oxidation technique based on UV-C irradiation and boron-doped diamond (BDD) anode and its application for the effective removal of the commercial herbicide halosulfuron-methyl (HSM). The study evaluated the influence of the following key operating variables in the photoelectrochemical process: current density, pH, temperature, and initial HSM concentration. With regard to HSM degradation/mineralization, the application of high current densities was found to be more advantageous once it promoted a more rapid degradation and mineralization, with 96% of total organic carbon removal, though the process became more energy-demanding over time. The initial concentration of HSM did not modify the relative degradation rate, though the degradation process became more efficient as expected in a mass-transfer controlled process. The use of acidic pH (pH 3) was found to be more suitable than neutral conditions; this is probably because an anionic resonant form of HSM may be formed in neutral conditions. The temperature level was also found to affect the rate of HSM removal and the degradation efficiency. Finally, the substitution of Na2SO4 by NaCl promoted a more rapid and effective degradation; this is attributed to high production of powerful oxidants. However, only 70% mineralization was reached after 3 h of treatment; this is probably related to the formation of recalcitrant chlorinated sub-products.
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Affiliation(s)
- Beatriz Rodrigues Pinto
- Center for Human and Natural Sciences, Federal University of ABC, CEP 09210-580, Avenida dos Estados, Santo André, SP, 5001, Brazil
| | - Jose Joaquin Linares
- Institute of Chemistry, University of Brasília, CEP 71605-00, Campus Darcy Ribeiro, Brasília, DF, Brazil
| | | | - Fernanda de Lourdes Souza
- Center for Human and Natural Sciences, Federal University of ABC, CEP 09210-580, Avenida dos Estados, Santo André, SP, 5001, Brazil.
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10
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Peng F, Yang F, Lu Y, Li H, Yang Z. Formation of disinfection byproducts during chlorination of mixed nitrogenous compounds in swimming pools. Sci Total Environ 2021; 754:142100. [PMID: 32916492 DOI: 10.1016/j.scitotenv.2020.142100] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/29/2020] [Accepted: 08/29/2020] [Indexed: 06/11/2023]
Abstract
Disinfection byproducts (DBPs) in swimming pool waters are receiving increasing attention because of their toxicity and widespread occurrence. Current studies rarely investigate the formation of DBPs from typical precursors in swimming pools under mixed exposure. They also rarely investigate the formation of carbonaceous DBPs (C-DBPs) and nitrogenous DBPs (N-DBPs) simultaneously. In this study, the formation of C-DBPs and N-DBPs were investigated during chlorination of mixed precursors (i.e., tryptophan, urea, creatinine, and ammonia). The effects of precursors and operation parameters were also investigated. Among the four precursors, tryptophan had the highest DBP formation potential. Urea and ammonia restrained the formation of C-DBPs but promoted the formation of more toxic N-DBPs. C-DBP yields were significantly higher than N-DBP yields under all experimental conditions. Longer reaction time and higher chlorine dosage promoted the formation of C-DBPs, while higher temperature decreased the concentration of N-DBPs. The presence of bromide not only improved the sum yields of DBPs, but also shifted chlorinated DBPs to brominated species.
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Affiliation(s)
- Fangyuan Peng
- Center for Environment and Water Resources, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Changsha 410083, PR China
| | - Fang Yang
- Center for Environment and Water Resources, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Changsha 410083, PR China
| | - Yi Lu
- Center for Environment and Water Resources, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Changsha 410083, PR China
| | - Haipu Li
- Center for Environment and Water Resources, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Changsha 410083, PR China.
| | - Zhaoguang Yang
- Center for Environment and Water Resources, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, PR China; Key Laboratory of Hunan Province for Water Environment and Agriculture Product Safety, Changsha 410083, PR China.
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11
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Banakar VV, Sabnis SS, Gogate PR, Raha A. Improvements in heat transfer in thermal desalination operation based on removal of salts using ultrasound pretreatment. Ultrason Sonochem 2020; 69:105251. [PMID: 32682312 DOI: 10.1016/j.ultsonch.2020.105251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 06/20/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
Scaling is a major problem in the thermal desalination operation which is mainly attributed to the deposition of salts on the tube, thereby increasing the resistance to heat transfer. To reduce or prevent the formation of scale on heat transfer surfaces, treating desalination concentrates and precipitating sparingly soluble salts can be a promising method. In the present work, the effect of ultrasound pretreatment to the synthetically prepared sea water as desalination feed has been investigated with an objective of intensifying salt removal process and avoiding scale formation leading to better heat transfer rates. A lab scale double pipe heat exchanger setup was designed and operated under simulated conditions of the thermal desalination operation. Total operational volume of 2000 ml was used for all experiments with a fixed flow rate of 5 ml/s. To understand the process of scaling, synthetic seawater was prepared as per the ASTM D 1141-98 and was used for scale deposition experiments. The experiments conducted using untreated synthetic seawater confirmed substantial scaling and drop in the heat transfer coefficient from an initial value of 776 W/m2 K to 603 W/m2 K (about 22%) after 24 h operation as compared to deionized water. SEM-EDX analysis was performed to investigate the morphology and main components of the scale. Subsequently, synthetic seawater was treated with ultrasound under continuous flow condition for removal of salts responsible for scaling. It was demonstrated that pretreatment resulted into salt crystallization, after which, the crystals were separated and the filtered solution was passed through the heat exchanger to check the effects on heat transfer rate. It was confirmed that the heat transfer rate was found to be higher with a value of 797 W/m2 K. Overall an effective approach based on ultrasound to remove the scale forming components has been demonstrated with established best conditions as 70% amplitude for 30 min of irradiation at fixed frequency of 20 kHz and 50% duty cycle.
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Affiliation(s)
- Vikram V Banakar
- Chemical Engineering Department, Institute of Chemical Technology, N.P. Marg, Matunga, Mumbai 400 019, India
| | - Sarvesh S Sabnis
- Chemical Engineering Department, Institute of Chemical Technology, N.P. Marg, Matunga, Mumbai 400 019, India
| | - Parag R Gogate
- Chemical Engineering Department, Institute of Chemical Technology, N.P. Marg, Matunga, Mumbai 400 019, India.
| | - Abhijit Raha
- Desalination Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
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12
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Tang Y, He D, Guo Y, Qu W, Shang J, Zhou L, Pan R, Dong W. Electrochemical oxidative degradation of X-6G dye by boron-doped diamond anodes: Effect of operating parameters. Chemosphere 2020; 258:127368. [PMID: 32554018 DOI: 10.1016/j.chemosphere.2020.127368] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [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: 03/21/2020] [Revised: 06/05/2020] [Accepted: 06/07/2020] [Indexed: 06/11/2023]
Abstract
Boron-doped diamond (BDD) is an excellent electrode material. As the anode in an electrochemical degradation tank, BDD has been receiving widespread attention for the treatment of azo dye wastewater. In this study, electrochemical oxidation (EO) was applied to electrolyze reactive brilliant yellow X-6G (X-6G) using BDD as the anode and Pt as the cathode. To balance the degradative effects and power consumption in the electrolysis process, the effects of a series of operating parameters, including current density, supporting electrolyte, initial pH, reaction temperature and initial dye concentration, were systematically studied. The oxidative process was analyzed by color removal rate, and the degree of mineralization was evaluated by TOC. The optimal experimental parameters were finally determined: 100 mA cm-2, 0.05 M Na2SO4 electrolyte, pH 3.03, 60 °C, and an initial X-6G concentration of 100 mg L-1. As a result, color completely disappeared after 0.75 h of electrolysis, and TOC was removed by 72.8% after 2 h of electrolysis. In conclusion, the EO of a BDD electrode as an anode can be a potent treatment method for X-6G synthetic wastewater.
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Affiliation(s)
- Yining Tang
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Deliang He
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China.
| | - Yanni Guo
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Wei Qu
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Jun Shang
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Lei Zhou
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Rong Pan
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
| | - Wei Dong
- College of Chemistry and Chemical Engineering, Hunan University, Changsha, 410082, China
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13
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Ogunlade CA, Aremu AK. Modeling and optimisation of oil recovery and throughput capacity in mechanically expressing oil from African oil bean ( Pentaclethra macrophylla Benth) kernels. J Food Sci Technol 2020; 57:4022-31. [PMID: 33071324 DOI: 10.1007/s13197-020-04435-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 02/28/2020] [Accepted: 04/08/2020] [Indexed: 10/24/2022]
Abstract
The relationship existing between operating parameters like speed of operation, applied pressure, feed rate and dependent variables like oil recovery and throughput capacity was investigated while mechanically expressing oil from kernels of Pentaclethra macrophylla. A 3-factor, 5-levels central composite design of response surface methodology was used for modeling and optimization of the process. The speed was varied over 15, 30, 45, 60 and 75 rpm using pulley arrangement, applied pressure was varied over 5, 10, 15, 20 and 25 MPa by adjusting the wormshaft distance of the oil expeller and the feed rate was varied over 100, 200, 300, 400 and 500 g/min by regulating the quantity of kernels fed into the expeller. Developed models were validated by comparing predicted values with experimental values. In optimizing the process, the oil recovery and throughput capacity were maximized while the independent variables were set at ranges. Optimum oil recovery of 73.2% and throughput capacity of 4.18 kg/h was obtained at 45 rpm speed of operation, 20 MPa applied pressure and 300 g/min feed rate. A quadratic polynomial model was developed for the oil recovery while a two-factorial-interaction model was developed for the throughput capacity. The results showed that speed of operation, applied pressure and feed rate had significant influence on the oil recovery and throughput capacity. The models developed were valid as they showed a good agreement between the variable due to low variations between calculated and predicted values.
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14
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Zaied BK, Rashid M, Nasrullah M, Zularisam AW, Pant D, Singh L. A comprehensive review on contaminants removal from pharmaceutical wastewater by electrocoagulation process. Sci Total Environ 2020; 726:138095. [PMID: 32481207 DOI: 10.1016/j.scitotenv.2020.138095] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [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: 01/04/2020] [Revised: 03/19/2020] [Accepted: 03/19/2020] [Indexed: 05/28/2023]
Abstract
The pharmaceuticals are emergent contaminants, which can create potential threats for human health and the environment. All the pharmaceutical contaminants are becoming enormous in the environment as conventional wastewater treatment cannot be effectively implemented due to toxic and intractable action of pharmaceuticals. For this reason, the existence of pharmaceutical contaminants has brought great awareness, causing significant concern on their transformation, occurrence, risk, and fate in the environments. Electrocoagulation (EC) treatment process is effectively applied for the removal of contaminants, radionuclides, pesticides, and also harmful microorganisms. During the EC process, an electric current is employed directly, and both electrodes are dissoluted partially in the reactor under the special conditions. This electrode dissolution produces the increased concentration of cation, which is finally precipitated as hydroxides and oxides. Different anode materials usage like aluminum, stainless steel, iron, etc. are found more effective in EC operation for efficient removal of pharmaceutical contaminants. Due to the simple procedure and less costly material, EC method is extensively recognized for pharmaceutical wastewater treatment over further conventional treatment methods. The EC process has more usefulness to destabilize the pharmaceutical contaminants with the neutralization of charge and after that coagulating those contaminants to produce flocs. Thus, the review places particular emphasis on the application of EC process to remove pharmaceutical contaminants. First, the operational parameters influencing EC efficiency with the electroanalysis techniques are described. Second, in this review emerging challenges, current developments and techno-economic concerns of EC are highlighted. Finally, future recommendations and prospective on EC are envisioned.
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Affiliation(s)
- B K Zaied
- Faculty of Civil Engineering Technology, Universiti Malaysia Pahang (UMP), Gambang, 26300 Kuantan, Pahang, Malaysia
| | - Mamunur Rashid
- Faculty of Electrical and Electronics Engineering Technology, Universiti Malaysia Pahang (UMP), 26600 Pekan, Pahang, Malaysia
| | - Mohd Nasrullah
- Faculty of Civil Engineering Technology, Universiti Malaysia Pahang (UMP), Gambang, 26300 Kuantan, Pahang, Malaysia; Faculty of Chemical and Process Engineering Technology, Universiti Malaysia Pahang (UMP), Gambang, 26300, Kuantan, Pahang, Malaysia
| | - A W Zularisam
- Faculty of Civil Engineering Technology, Universiti Malaysia Pahang (UMP), Gambang, 26300 Kuantan, Pahang, Malaysia
| | - Deepak Pant
- Separation and Conversion Technology, Flemish Institute for Technological Research (VITO), Boeretang 200, Mol 2400, Belgium
| | - Lakhveer Singh
- Department of Environmental Science, SRM University-AP, Amaravati, Andhra Pradesh - 522502, India.
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15
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Jia T, Sun S, Chen K, Zhang L, Peng Y. Simultaneous methanethiol and dimethyl sulfide removal in a single-stage biotrickling filter packed with polyurethane foam: Performance, parameters and microbial community analysis. Chemosphere 2020; 244:125460. [PMID: 31809922 DOI: 10.1016/j.chemosphere.2019.125460] [Citation(s) in RCA: 3] [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: 09/01/2019] [Revised: 11/08/2019] [Accepted: 11/22/2019] [Indexed: 06/10/2023]
Abstract
The bio-treatment of methanethiol (MT) and dimethyl sulfide (DMS), the most common sulfur compounds in odorous gas, is difficult due to the inhibition of DMS degradation by MT. This article investigated the treatment of MT and DMS odorous gas using a single-stage biotrickling filter (BTF) packed with polyurethane foam cubes that were inoculated with activated sludge from a sewage treatment plant operating an anaerobic/aerobic/oxic (AAO) process. The BTF system lasted for 161 days (with 9 days to startup) under an empty gas residence time of 39 s. The elimination capacities for MT and DMS were 85.2 g/m3/h (removal efficiency = 96.6%) and 6.4 g/m3/h (removal efficiency = 95.0%), respectively, and the maximal elimination capacities of MT and DMS were 119.7 g/m3/h and 7.3 g/m3/h, respectively. The optimal parameters were as follows: empty bed retention time, 39 s; pH, 6.1; recirculation medium flow rate, ≥1.2 m3/m2/h; temperature, 29-36 °C; and SO42- concentration, < 2.0 g-SO42-/L. Microbial community analysis revealed that spatial differentiation between MT-degrading bacteria and DMS-degrading bacteria enable the single-stage BTF can simultaneously remove MT and DMS. The activated sludge of AAO process can be used as the inoculation sludge to treating MT and DMS gas, which provides an important reference for the industrial application of treating odorous gas containing MT and DMS.
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Affiliation(s)
- Tipei Jia
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Shihao Sun
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Kaiqi Chen
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Key Laboratory of Beijing Water Quality Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, 100124, China.
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16
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Luo Y, Yao J, Wang X, Zheng M, Guo D, Chen Y. Efficient municipal wastewater treatment by oxidation ditch process at low temperature: Bacterial community structure in activated sludge. Sci Total Environ 2020; 703:135031. [PMID: 31726299 DOI: 10.1016/j.scitotenv.2019.135031] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [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: 07/23/2019] [Revised: 10/10/2019] [Accepted: 10/16/2019] [Indexed: 06/10/2023]
Abstract
Temperature is a key element affecting the activity of microorganisms in activated sludge. Low water temperature generally leads to decreasing wastewater treatment efficiency and destroying sludge settleability. In this study, activated sludge samples from a municipal wastewater treatment plant (WWTP) implementing oxidation ditch process was used to investigate the bacterial community characteristics of a system that operates well in a cold region (Xinjiang, China) by high-throughput 16S rRNA gene sequencing. The results showed that the influent temperature was 7-12 °C in winter and 13-17 °C in summer, while the sludge volume index (SVI) of samples was between 51 and 74 mL/g. The average removal efficiencies for chemical oxygen demand (COD), biochemical oxygen demand (BOD5), suspended solid (SS), ammonia nitrogen (NH4+-N), total nitrogen (TN), and total phosphorus (TP) were 94%, 95%, 95%, 91%, 73% and 89%, respectively. The bacteria were distributed in 32 phyla and 559 genera. The dominant phyla were Proteobacteria (28.85-48.45%), Bacteroidetes (20.00-31.22%), Chloroflexi (3.59-12.23%), Actinobacteria (1.58-15.54%) and Firmicutes (1.38-10.49%). The dominant genera were Saprospiraceae_norank (4.41-12.23%), Comamonadaceae_unclassified (3.82-8.83%), Anaerolineaceae_norank (1.39-9.35%), Dokdonella (1.13-11.26%), Candidatus_Microthrix (0.26-7.50%), Flavobacterium (0.32-8.14%), Ferribacterium (0.36-5.19%) and Nitrospira (0.084-5.37%), which were different from those found in warm-region WWTPs. Contrary to previous studies, the relative abundance of ammonia-oxidizing bacteria (AOB; Nitrosomonas and Nitrosomonadaceae) and nitrite-oxidizing bacteria (NOB; Nitrospira) increased when the temperature decreased. The successful operation of this WWTP suggests that cold-region WWTPs can achieve good pollutants removal efficiency by simultaneously maintaining an ultra-low sludge load and high dissolved oxygen concentration in the oxidation ditch. The findings of this study provide fundamental knowledge required for an efficient and stable operation of WWTPs in cold regions.
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Affiliation(s)
- Yuanshuang Luo
- College of Resources and Environmental Science, Xinjiang University, Urumqi, Xinjiang, China
| | - Junqin Yao
- College of Resources and Environmental Science, Xinjiang University, Urumqi, Xinjiang, China.
| | - Xiyuan Wang
- College of Resources and Environmental Science, Xinjiang University, Urumqi, Xinjiang, China
| | - Meiying Zheng
- Altay Sewage Purification and Management Institute, Altay, Xinjiang, China
| | - Deyong Guo
- Altay Sewage Purification and Management Institute, Altay, Xinjiang, China
| | - Yinguang Chen
- College of Resources and Environmental Science, Xinjiang University, Urumqi, Xinjiang, China; College of Environmental Science and Engineering, Tongji University, Shanghai, China
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17
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Viet ND, Cho J, Yoon Y, Jang A. Enhancing the removal efficiency of osmotic membrane bioreactors: A comprehensive review of influencing parameters and hybrid configurations. Chemosphere 2019; 236:124363. [PMID: 31325824 DOI: 10.1016/j.chemosphere.2019.124363] [Citation(s) in RCA: 5] [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: 05/06/2019] [Revised: 06/30/2019] [Accepted: 07/12/2019] [Indexed: 06/10/2023]
Abstract
The amount of research conducted on osmotic membrane bioreactors (OMBRs) has increased over the past decade because of the advantages of these reactors over conventional membrane bioreactors (MBRs). OMBR process is a hybrid process involving a forward osmosis membrane and biologically activated sludge. It is a promising technology to reduce membrane fouling, enhance effluent water quality, and lower energy consumption compared to conventional MBR processes. Eleven years since the OMBR process was first proposed, about 60 papers regarding the OMBR process have been published. In this article, we address recent advances in OMBR technology based on a review of the literature. Typical factors that influence the performance of the OMBR process are discussed to provide a clear understanding of the current state of this technology. We also provide a critical review of OMBR applications in organic matter, nutrient, and micropollutant removal as well as direct recovery of nutrients from wastewater. We propose several hybrid configurations that can enhance the removal efficiency of OMBR systems. Finally, we present potential research directions for future OMBR research.
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Affiliation(s)
- Nguyen Duc Viet
- Graduate School of Water Resources, Sungkyunkwan University, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea
| | - Jaeweon Cho
- School of Urban and Environmental Engineering, Ulsan Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan, 689-798, Republic of Korea
| | - Yeomin Yoon
- Department of Civil and Environmental Engineering, University of South Carolina, Columbia, 300 Main Street, SC, 29208, USA
| | - Am Jang
- Graduate School of Water Resources, Sungkyunkwan University, Jangan-gu, Suwon, Gyeonggi-do, 16419, Republic of Korea.
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18
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Wang Y, Guo L, Zhang J, She Z, Jin C, Gao M, Zhao Y. Optimization of operating conditions for the acidification metabolites production with waste sludge using response surface methodology (RSM). Environ Sci Pollut Res Int 2019; 26:30303-30312. [PMID: 31432371 DOI: 10.1007/s11356-019-06088-9] [Citation(s) in RCA: 2] [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: 03/15/2019] [Accepted: 07/26/2019] [Indexed: 06/10/2023]
Abstract
The acidification liquid of waste activated sludge (WAS) could be used as the additional carbon source of biological nutrient removal. Recently, the optimization of operating conditions for the acidification metabolites has attracted much attention. In this study, a three-factor Box-Behnken design (BBD) was applied to determine the relative importance of the various factors and the optimum operating during acidification using response surface method (RSM). The importance of the individual variables on the production of soluble chemical oxygen demand (SCOD) was suspended solids (SS) > shaking rate > initial oxidation-reduction potential (ORP). The increase on SS content led to a decrease on the acidification degree. Low SS could promote mass exchange and microbial activity. The maximum SCOD yield (9288.5 mg/L) was predicted under the optimum condition at 8.0 g/L SS, 144.0 mV initial ORP, and 60.0 r/min shaking rate. Also, the releasing of soluble protein and carbohydrate was calculated as responses. The individual effect of shaking rate and initial ORP had significant effect on soluble protein and carbohydrate releasing, respectively. This study would provide valuable information for increasing the efficiency of acidification.
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Affiliation(s)
- Yu Wang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
- Key Laboratory of Marine Environmental and Ecology, Ministry of Education, Ocean University of China, Qingdao, 266100, China.
- Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering, Ocean University of China, Qingdao, 266100, China.
| | - Jiawen Zhang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Zonglian She
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Chunji Jin
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Mengchun Gao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Yangguo Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
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19
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Morley R, Minceva M. Operating mode and parameter selection in liquid-liquid chromatography. J Chromatogr A 2019; 1617:460479. [PMID: 31477275 DOI: 10.1016/j.chroma.2019.460479] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 07/29/2019] [Accepted: 08/22/2019] [Indexed: 12/27/2022]
Abstract
The presence of a liquid stationary phase in liquid-liquid chromatography (LLC) allows for high versatility of operation as well as adaptability to different sample types and separation tasks. LLC, also known as countercurrent chromatography (CCC) or centrifugal partition chromatography (CPC), offers the user a variety of operating modes, many of which have no direct equivalent in conventional preparative liquid-solid chromatography. These operating modes have the potential to greatly improve LLC separation performance compared to the standard "classical" isocratic batch injection mode, and they often require minimal to no addition of equipment to the standard set-up. However, reports of the use of alternative LLC operating modes make up only a fraction of the literature. This is likely due, at least in part, to the lack of clear guidelines and methods for operating mode and parameter selection, leaving alternative process options to be avoided and underutilized. This review seeks to remedy this by providing a thorough overview of the available LLC operating modes, identifying the key characteristics, advantages and disadvantages, and areas of application of each. Additionally, the equations and short-cut models aiding in operating mode and parameter selection are presented and critiqued, and their notation is unified for clarity. By rendering LLC and its alternative operating modes more accessible to current and prospective users, it is hoped to help expand the application of this technology and support the achievement of its full potential.
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Affiliation(s)
- Raena Morley
- Biothermodynamics, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Maximus-von-Imhof-Forum 2, 85354 Freising, Germany
| | - Mirjana Minceva
- Biothermodynamics, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Maximus-von-Imhof-Forum 2, 85354 Freising, Germany.
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20
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Ding Y, Wei J, Xiong J, Zhou B, Cai H, Zhu W, Zhang H. Effects of operating parameters on in situ NH 3 emission control during kitchen waste composting and correlation analysis of the related microbial communities. Environ Sci Pollut Res Int 2019; 26:11756-11766. [PMID: 30815814 DOI: 10.1007/s11356-019-04605-4] [Citation(s) in RCA: 2] [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: 10/04/2018] [Accepted: 02/18/2019] [Indexed: 06/09/2023]
Abstract
Ammonia emission during composting results in anthropogenic odor nuisance and reduces the agronomic value of the compost due to the loss of nitrogen. Adjusting the operating parameters during composting is an emerging in situ odor control technique that is cheap and highly efficient. The effects of in situ NH3 emission control were investigated in this study by simultaneously adjusting key operating parameters (such as C/N ratio, aeration rate, and moisture content) during the composting processes (C1-C9). Results showed that the average NH3 emission concentrations for different treatments were in the order of C1 > C4 > C2 > C5 > C3 > C6 > C7 > C8 > C9. The total content of NH3 emission (21.02 g/kg) in C9 (C/N ratio = 35, aeration rate = 15 L/min, and moisture content = 60%) was much lower than that (65.95 g/kg) in C1 (C/N ratio = 15, aeration rate = 5 L/min, and moisture content = 60%). The nitrogen loss ratio was 27.36% for C1, while 16.15% for C9. The microbial diversity and abundance in C9 and C1 were compared using high-throughput sequencing. The relationship between NH3 emission, operating parameters, and the related functional microbial communities was also investigated. Results revealed that Nitrosospira, Nitrosomonas, Nitrobacter, Pseudomonas, Methanosaeta, Rhodobacter, Paracoccus, and Sphingobacterium were negatively related to NH3 emission. According to the above results, the optimal values for different operating parameters for the in situ NH3 control during kitchen waste composting were, respectively, moisture content of 70%, C/N ratio of 35, and aeration rate of 15 L/min, with the order of effectiveness from high to low being aeration rate > C/N > moisture. This information could be used as a valuable reference for the in situ NH3 emission control during kitchen waste composting.
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Affiliation(s)
- Ying Ding
- Department of Environmental Engineering, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China.
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China.
| | - Jiaojiao Wei
- Department of Environmental Engineering, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
| | - Junsheng Xiong
- Department of Environmental Engineering, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
| | - Bowei Zhou
- Department of Environmental Engineering, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
| | - Hanjiang Cai
- China National Bamboo Research Center, Hangzhou, 310012, People's Republic of China
| | - Weiqin Zhu
- Department of Environmental Engineering, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
| | - Hangjun Zhang
- Department of Environmental Engineering, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
- Key Laboratory of Hangzhou City for Ecosystem Protection and Restoration, Hangzhou Normal University, Hangzhou, 310016, People's Republic of China
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21
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Yao Y, Li M, Yang Y, Cui L, Guo L. Electrochemical degradation of insecticide hexazinone with Bi-doped PbO 2 electrode: Influencing factors, intermediates and degradation mechanism. Chemosphere 2019; 216:812-822. [PMID: 30404074 DOI: 10.1016/j.chemosphere.2018.10.191] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [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: 07/31/2018] [Revised: 10/16/2018] [Accepted: 10/27/2018] [Indexed: 06/08/2023]
Abstract
Electrochemical degradation of hexazinone in aqueous solution using Bi-doped PbO2 electrodes as anodes was investigated. The main influencing parameters on the electrocatalytic degradation of hexazinone were analyzed as function of initial hexazinone concentration, current density, initial pH value and Na2SO4 concentration. The experiment results showed that the electrochemical oxidization reaction of hexazinone fitted pseudo-first-order kinetics model. 99.9% of hexazinone can be decontaminated using Bi-doped PbO2 electrode as anode for 120 min. Comparing with pure PbO2 electrode, the Bi-doped PbO2 electrodes possess higher hexazinone and COD removal ratio, higher ICE and lower energy consumption in the electrocatalytic degradation process. The results revealed that electrochemical oxidation using Bi-doped PbO2 anodes was an efficient method for the elimination of hexazinone in aqueous solution. The electrocatalytic oxidization mechanism of hexazinone with Bi-doped PbO2 anode was discussed, then the possible degradation pathway of hexazinone with two parallel sub-routes was elucidated according to 15 intermediates identified using HPLC-MS.
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Affiliation(s)
- Yingwu Yao
- Hebei University of Technology, School of Chemical Engineering and Technology, Tianjin 300130, PR China.
| | - Mengyao Li
- Hebei University of Technology, School of Chemical Engineering and Technology, Tianjin 300130, PR China
| | - Yang Yang
- Hebei University of Technology, School of Chemical Engineering and Technology, Tianjin 300130, PR China.
| | - Leilei Cui
- Hebei University of Technology, School of Chemical Engineering and Technology, Tianjin 300130, PR China
| | - Lin Guo
- Hebei University of Technology, School of Chemical Engineering and Technology, Tianjin 300130, PR China
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Iftekhar S, Ramasamy DL, Srivastava V, Asif MB, Sillanpää M. Understanding the factors affecting the adsorption of Lanthanum using different adsorbents: A critical review. Chemosphere 2018; 204:413-430. [PMID: 29677649 DOI: 10.1016/j.chemosphere.2018.04.053] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [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: 03/06/2018] [Revised: 04/08/2018] [Accepted: 04/10/2018] [Indexed: 05/10/2023]
Abstract
Over the past few decades, removal and recovery of Lanthanum (La) have received great attention due to its significance in different industrial processes. In this review, the application of various adsorbents viz. biosorbents, commercial and hybrid materials, nanoparticles, nanocomposites etc. have been summarized in terms of the removal and recovery of La. The influence of various operating parameters including pH, dosage, contact time, temperature, coexisting ions, adsorption kinetics, isotherm and thermodynamics were investigated. Statistical analysis of the obtained data revealed that 60% and 70% of the authors reported an optimum pH of 4-6 and a dose of 1-2 g/L, respectively. It can be concluded on the basis of an extensive literature survey that the adsorbent materials (especially hybrids nanocomposites) containing carboxyl, hydroxyl and amine groups offered efficient La removal over a wide range of pH with higher adsorption capacity as compared to other adsorbents (e.g., biosorbents and magnetic adsorbents). Also, in most cases, equilibrium and kinetics were followed by Langmuir and pseudo second-order model and adsorption was endothermic in nature. To evaluate the adsorption efficiency of several adsorbents towards La, desorption and regeneration of adsorbents should be given due consideration. The main objective of the review is to provide an insight into the important factors that may affect the recovery of La using various adsorbents.
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Affiliation(s)
- Sidra Iftekhar
- Department of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland.
| | - Deepika Lakshmi Ramasamy
- Department of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland
| | - Varsha Srivastava
- Department of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland
| | - Muhammad Bilal Asif
- Strategic Water Infrastructure Laboratory, School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong NSW 2522, Australia
| | - Mika Sillanpää
- Department of Green Chemistry, School of Engineering Science, Lappeenranta University of Technology, Sammonkatu 12, FI-50130 Mikkeli, Finland; Department of Civil and Environmental Engineering, Florida International University, Miami, FL 33174, USA
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Sancheti SV, Gogate PR. Intensification of heterogeneously catalyzed Suzuki-Miyaura cross-coupling reaction using ultrasound: Understanding effect of operating parameters. Ultrason Sonochem 2018; 40:30-39. [PMID: 28214134 DOI: 10.1016/j.ultsonch.2017.01.037] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 01/18/2017] [Accepted: 01/25/2017] [Indexed: 06/06/2023]
Abstract
Palladium-catalyzed Suzuki-Miyaura cross-coupling reaction is a significant reaction for obtaining industrially important products. The current research work deals with intensification of reaction of 4-bromoanisole and phenylboronic acid catalyzed with 5wt% Pd/C (5% by weight Pd supported on C available as commercial catalyst) using ultrasound and more importantly, without use of any additional phase transfer catalyst. Heterogeneous catalyst has been selected in the present work so as to harness the benefits of easy separation and the possible limitations of heterogeneous operation are minimized by introducing ultrasonic irradiations. The effect of operating parameters such as ultrasound power, temperature, catalyst loading and molar ratio on the progress of reaction has been investigated. It has been observed that an optimum power, temperature and catalyst loading exist for maximum benefits whereas higher molar ratio was found to be favourable for the progress of the reaction. Also, the use of ultrasound reduced the reaction time from 70min required in conventional approach to only 35min under conditions of frequency of 22kHz, power dissipation of 40W and catalyst loading as 1.5mol% (refers to total quantum of catalyst used in the work) in ethanol-water system under ambient conditions. The work also demonstrated successful results at ten times higher volume as compared to the normally used volumes in the case of simple ultrasonic horn. Overall, the work has successfully demonstrated process intensification benefits obtained due to the use of ultrasound for heterogeneously catalyzed Suzuki-Miyaura cross-coupling reaction.
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Affiliation(s)
- Sonam V Sancheti
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India
| | - Parag R Gogate
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India.
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Xu L, Cao G, Xu X, Liu S, Duan Z, He C, Wang Y, Huang Q. Simultaneous removal of cadmium, zinc and manganese using electrocoagulation: Influence of operating parameters and electrolyte nature. J Environ Manage 2017; 204:394-403. [PMID: 28915474 DOI: 10.1016/j.jenvman.2017.09.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [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: 06/03/2017] [Revised: 08/31/2017] [Accepted: 09/06/2017] [Indexed: 06/07/2023]
Abstract
In the present study, the influence of operating parameters and electrolyte nature on the simultaneous removal of toxic metals (cadmium, zinc and manganese) from synthetic smelting wastewater by batch electrocoagulation was investigated. This wastewater contained high concentrations of anion-cation electrolytes. Results indicated that the efficiency of heavy metals removal can be enhanced by increasing the solution pH and current density. The Fe-Fe electrode combination is more effective than the other combinations (Al-Al, Al-Fe and Fe-Al). The interaction of heavy metal ions showed that the increase of initial Zn2+ concentration adversely affects on Cd2+ removal. In addition, the single chloride system exhibits the optimum removal efficiency on Mn2+. Single sulfate and binary anion systems exert a more positive effect on Cd2+ and Zn2+ removal because of the stronger charge neutralization and destabilization of iron hydroxide flocs. Increases of Ca2+ and Mg2+ ions exert a significant negative effect on metal removal. However, the addition of a small amount of sodium chloride into a high sulfate and hardness solution can accelerate the removal of heavy metals. Finally, the sludge samples generated from electrocoagulation were characterized by XRD and SEM-EDS analyses.
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Affiliation(s)
- Longqian Xu
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Guangzhu Cao
- Faculty of Land Resource Engineering, Kunming University of Science and Technology, 650500 Kunming, China.
| | - Xiaojun Xu
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Shuli Liu
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Zhengyang Duan
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Changhua He
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yao Wang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Qihua Huang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
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25
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Thanh PM, Ketheesan B, Zhou Y, Stuckey DC. Effect of operating conditions on speciation and bioavailability of trace metals in submerged anaerobic membrane bioreactors. Bioresour Technol 2017; 243:810-819. [PMID: 28724252 DOI: 10.1016/j.biortech.2017.07.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 05/14/2017] [Revised: 07/05/2017] [Accepted: 07/06/2017] [Indexed: 06/07/2023]
Abstract
This study investigated the effect of changes in pH (7, 6.5 and 6), hydraulic retention time (HRT) (6h, 4h, and 2h), solids retention time (SRT) (100d and 25d) on the speciation of trace metals (TMs) in submerged anaerobic membrane bioreactors (SAMBRs). The results showed that the metal retention capacity of SAMBRs reduced when the pH, HRT and SRT were reduced i.e. up to 21.9%, 39.1%, and 17.1%, respectively, but it was also found that the speciation of these TMs generally shifted towards highly bioavailable fractions i.e. Soluble and Exchangeable. The degree of shifting in speciation depended on the affinity of the TMs for anaerobic sludge and their sensitivity to the changes. TMs with the most and the least significant changes in speciation were Fe and Mn, respectively.
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Affiliation(s)
- Pham Minh Thanh
- Interdisciplinary Graduate School, Nanyang Technological University, Singapore 639798, Singapore; Nanyang Environment & Water Research Institute, Advanced Environmental Biotechnology Centre, Nanyang Technological University, Singapore 637141, Singapore
| | - Balachandran Ketheesan
- Nanyang Environment & Water Research Institute, Advanced Environmental Biotechnology Centre, Nanyang Technological University, Singapore 637141, Singapore
| | - Yan Zhou
- Nanyang Environment & Water Research Institute, Advanced Environmental Biotechnology Centre, Nanyang Technological University, Singapore 637141, Singapore; School of Civil & Environmental Engineering, College of Engineering, Nanyang Technological University, Singapore 637141, Singapore
| | - David C Stuckey
- Nanyang Environment & Water Research Institute, Advanced Environmental Biotechnology Centre, Nanyang Technological University, Singapore 637141, Singapore; Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK.
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26
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Outsiou A, Frontistis Z, Ribeiro RS, Antonopoulou M, Konstantinou IK, Silva AMT, Faria JL, Gomes HT, Mantzavinos D. Activation of sodium persulfate by magnetic carbon xerogels (CX/CoFe) for the oxidation of bisphenol A: Process variables effects, matrix effects and reaction pathways. Water Res 2017; 124:97-107. [PMID: 28750289 DOI: 10.1016/j.watres.2017.07.046] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [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: 05/23/2017] [Revised: 07/17/2017] [Accepted: 07/18/2017] [Indexed: 06/07/2023]
Abstract
An advanced oxidation process comprising sodium persulfate (SPS) and a novel magnetic carbon xerogel was tested for the degradation of bisphenol A (BPA), a model endocrine-disrupting compound. The catalyst, consisting of interconnected carbon microspheres with embedded iron and cobalt microparticles, was capable of activating persulfate to form sulfate and hydroxyl radicals at ambient conditions. The pseudo-first order degradation rate of BPA in ultrapure water (UPW) was found to increase with (i) increasing catalyst (25-75 mg/L) and SPS (31-250 mg/L) concentrations, (ii) decreasing BPA concentration (285-14,200 μg/L), and (iii) changing pH from alkaline to acidic values (9-3). Besides UPW, tests were conducted in drinking water, treated wastewater, groundwater and surface water; interestingly, the rate in UPW was always lower than in any other matrix containing several organic and inorganic constituents. The effect of natural organic matter (in the form of humic acids) and alcohols was detrimental to BPA degradation owing to the scavenging of radicals. Conversely, chlorides at concentrations greater than 50 mg/L had a positive effect due to the formation and subsequent participation of chlorine-containing radicals. Liquid chromatography time-of-flight mass spectrometry was employed to identify major transformation by-products (TBPs) of BPA degradation in the absence and presence of chlorides; in the latter case, several chlorinated TBPs were detected confirming the role of Cl-related radicals. Based on TBPs, main reaction pathways are proposed.
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Affiliation(s)
- Alexandra Outsiou
- Department of Chemical Engineering, University of Patras, Caratheodory 1, University Campus, GR-26504 Patras, Greece
| | - Zacharias Frontistis
- Department of Chemical Engineering, University of Patras, Caratheodory 1, University Campus, GR-26504 Patras, Greece
| | - Rui S Ribeiro
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Escola Superior de Tecnologia e Gestão, Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal; Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Maria Antonopoulou
- Department of Environmental and Natural Resources Management, University of Patras, 2 Seferi St., GR-30100 Agrinio, Greece
| | - Ioannis K Konstantinou
- Department of Chemistry, Laboratory of Industrial Chemistry, University of Ioannina, GR-45110 Ioannina, Greece
| | - Adrián M T Silva
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Joaquim L Faria
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Faculdade de Engenharia, Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Helder T Gomes
- Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Escola Superior de Tecnologia e Gestão, Instituto Politécnico de Bragança, Campus de Santa Apolónia, 5300-253 Bragança, Portugal
| | - Dionissios Mantzavinos
- Department of Chemical Engineering, University of Patras, Caratheodory 1, University Campus, GR-26504 Patras, Greece.
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Khalik WF, Ho LN, Ong SA, Voon CH, Wong YS, Yusoff N, Lee SL, Yusuf SY. Optimization of degradation of Reactive Black 5 (RB5) and electricity generation in solar photocatalytic fuel cell system. Chemosphere 2017; 184:112-119. [PMID: 28586651 DOI: 10.1016/j.chemosphere.2017.05.160] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [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: 02/02/2017] [Revised: 05/23/2017] [Accepted: 05/28/2017] [Indexed: 05/21/2023]
Abstract
The photocatalytic fuel cell (PFC) system was developed in order to study the effect of several operating parameters in degradation of Reactive Black 5 (RB5) and its electricity generation. Light irradiation, initial dye concentration, aeration, pH and cathode electrode are the operating parameters that might give contribution in the efficiency of PFC system. The degradation of RB5 depends on the presence of light irradiation and solar light gives better performance to degrade the azo dye. The azo dye with low initial concentration decolorizes faster compared to higher initial concentration and presence of aeration in PFC system would enhance its performance. Reactive Black 5 rapidly decreased at higher pH due to the higher amount of OH generated at higher pH and Pt-loaded carbon (Pt/C) was more suitable to be used as cathode in PFC system compared to Cu foil and Fe foil. The rapid decolorization of RB5 would increase their voltage output and in addition, it would also increase their Voc, Jsc and Pmax. The breakage of azo bond and aromatic rings was confirmed through UV-Vis spectrum and COD analysis.
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Affiliation(s)
- Wan Fadhilah Khalik
- Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia
| | - Li-Ngee Ho
- School of Materials Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia.
| | - Soon-An Ong
- Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia
| | - Chun-Hong Voon
- School of Materials Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia
| | - Yee-Shian Wong
- Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia
| | - NikAthirah Yusoff
- Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia
| | - Sin-Li Lee
- School of Materials Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia
| | - Sara Yasina Yusuf
- Water Research Group (WAREG), School of Environmental Engineering, Universiti Malaysia Perlis, Arau, Perlis, 02600, Malaysia
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28
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Chen Z, Chen Z, Yin F, Wang G, Chen H, He C, Xu Y. Supercritical water oxidation of oil-based drill cuttings. J Hazard Mater 2017; 332:205-213. [PMID: 28334620 DOI: 10.1016/j.jhazmat.2017.03.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 01/25/2017] [Accepted: 03/01/2017] [Indexed: 06/06/2023]
Abstract
Oil-based drill cuttings (OBDC) are a typical hazardous solid waste that arises from drilling operations in oil and gas fields. The supercritical water oxidation (SCWO) of OBDC was comprehensively investigated in a batch reactor under the conditions of various oxygen coefficients (OC, 1.5-3.5), temperatures (T, 400-500°C) and reaction times (t, 0.5-10min). Preheating experiments indicated that most of the organic compounds in the initial OBDC sample were distributed within gaseous, oil, aqueous and solid phases, with no more than 9.8% of organic compounds converted into inorganic carbon. All tested variables, i.e., OC, T and t, positively affect the transformation of carbon compounds from the oil and solid phases to the aqueous phase and, ultimately, to CO2. Carbon monoxide is the primary stable intermediate. The total organic carbon (TOC) removal efficiency can reach up to 89.2% within 10min at 500°C. Analysis of the reaction pathways suggests both homogeneous and heterogeneous reactions exist in the reactor. The homogeneous reaction is a typical SCWO reaction that is governed by a free radical mechanism, and the heterogeneous reaction is dominated by mass transfer. The information obtained in this study is useful for further investigation and development of hydrothermal treatment procedures for OBDC.
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Affiliation(s)
- Zhong Chen
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences, Chongqing 400714, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Zeliang Chen
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences, Chongqing 400714, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Fengjun Yin
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences, Chongqing 400714, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China; Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Guangwei Wang
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences, Chongqing 400714, PR China; Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Hongzhen Chen
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences, Chongqing 400714, PR China; Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing 400714, PR China
| | - Chunlan He
- Chongqing Institute for Food and Drug Control, Chongqing 401120, PR China
| | - Yuanjian Xu
- Chongqing Institute of Green and Intelligent Technology (CIGIT), Chinese Academy of Sciences, Chongqing 400714, PR China; Key Laboratory of Reservoir Aquatic Environment, Chinese Academy of Sciences, Chongqing 400714, PR China.
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Zhang J, Zuo W, Tian Y, Yin L, Gong Z, Zhang J. Release of hydrogen sulfide during microwave pyrolysis of sewage sludge: Effect of operating parameters and mechanism. J Hazard Mater 2017; 331:117-122. [PMID: 28249180 DOI: 10.1016/j.jhazmat.2017.02.040] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 02/21/2017] [Accepted: 02/22/2017] [Indexed: 06/06/2023]
Abstract
The effects of sludge characteristics, pyrolysis temperature, heating rate and catalysts on the release of H2S and mechanism of H2S formation during sludge pyrolysis were investigated in a microwave heating reactor (MHR). The evolution of sulfur-containing compounds in the pyrolysis chars obtained at temperature range of 400-800°C was characterized by XPS. For a given temperature, the maximum concentration of H2S appeared at moisture content of 80%. Compared to the influence of heating rate on the H2S yields, pyrolysis temperature and catalyst played a more significant role on the release of H2S during microwave pyrolysis process. The H2S concentration increased with increasing temperature from 400°C to 800°C while decreased with increasing heating rate. Both the Nickel-based catalyst and Dolomite displayed significant desulfurization effect and Ni-based catalyst exhibited the larger desulfurization capability than that of Dolomite. The organic sulfur compounds accounted for about 60% of the total sulfur in the sludge which was the main reason for the formation of H2S. The mechanism analysis indicated that the cleavage reactions of mercaptan and aromatic-S compounds at temperatures below 600°C and the cracking reaction of sulfate above 700°C respectively were responsible for the H2S release during sludge pyrolysis.
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Affiliation(s)
- Jun Zhang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
| | - Wei Zuo
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Yu Tian
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Linlin Yin
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Zhenlong Gong
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
| | - Jie Zhang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
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30
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Sancheti SV, Gogate PR. A review of engineering aspects of intensification of chemical synthesis using ultrasound. Ultrason Sonochem 2017; 36:527-543. [PMID: 27567541 DOI: 10.1016/j.ultsonch.2016.08.009] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Revised: 08/06/2016] [Accepted: 08/06/2016] [Indexed: 05/25/2023]
Abstract
Cavitation generated using ultrasound can enhance the rates of several chemical reactions giving better selectivity based on the physical and chemical effects. The present review focuses on overview of the different reactions that can be intensified using ultrasound followed by the discussion on the chemical kinetics for ultrasound assisted reactions, engineering aspects related to reactor designs and effect of operating parameters on the degree of intensification obtained for chemical synthesis. The cavitational effects in terms of magnitudes of collapse temperatures and collapse pressure, number of free radicals generated and extent of turbulence are strongly dependent on the operating parameters such as ultrasonic power, frequency, duty cycle, temperature as well as physicochemical parameters of liquid medium which controls the inception of cavitation. Guidelines have been presented for the optimum selection based on the critical analysis of the existing literature so that maximum process intensification benefits can be obtained. Different reactor designs have also been analyzed with guidelines for efficient scale up of the sonochemical reactor, which would be dependent on the type of reaction, controlling mechanism of reaction, catalyst and activation energy requirements. Overall, it has been established that sonochemistry offers considerable potential for green and sustainable processing and efficient scale up procedures are required so as to harness the effects at actual commercial level.
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Affiliation(s)
- Sonam V Sancheti
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India
| | - Parag R Gogate
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India.
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31
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Chen Y, Lan S, Wang L, Dong S, Zhou H, Tan Z, Li X. A review: Driving factors and regulation strategies of microbial community structure and dynamics in wastewater treatment systems. Chemosphere 2017; 174:173-182. [PMID: 28161518 DOI: 10.1016/j.chemosphere.2017.01.129] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [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: 10/14/2016] [Revised: 01/24/2017] [Accepted: 01/25/2017] [Indexed: 06/06/2023]
Abstract
The performance and stabilization of biological wastewater treatment systems 1are closely related to the microbial community structure and dynamics. In this paper, the effects and mechanisms of influent composition, process configuration, operating parameters (dissolved oxygen [DO], pH, hydraulic retention time [HRT] and sludge retention time [SRT]) and environmental condition (temperature) to the change of microbial community structure and process performance (nitrification, denitrification, biological phosphorus removal, organics mineralization and utilization, etc.) are critically reviewed. Furthermore, some strategies for microbial community structure regulation, mainly bioaugmentation, process adjustment and operating parameters optimization, applied in the current wastewater treatment systems are also discussed. Although the recent studies have strengthened our understanding on the relationship between microbial community structure and wastewater treatment process performance, how to fully tap the microbial information, optimize the microbial community structure and maintain the process performance in wastewater treatment systems are still full of challenges.
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Affiliation(s)
- Yangwu Chen
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; University of Chinese Academy of Sciences, 100049, Beijing, PR China
| | - Shuhuan Lan
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China
| | - Longhui Wang
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China
| | - Shiyang Dong
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; University of Chinese Academy of Sciences, 100049, Beijing, PR China
| | - Houzhen Zhou
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China
| | - Zhouliang Tan
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China.
| | - Xudong Li
- Key Laboratory of Environmental and Applied Microbiology, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China; Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, 610041, Chengdu, PR China
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Yu JF, Fu J, Cheng H, Cui Z. Recycling of rare earth particle by mini-hydrocyclones. Waste Manag 2017; 61:362-371. [PMID: 28011286 DOI: 10.1016/j.wasman.2016.12.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [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: 08/25/2016] [Revised: 11/15/2016] [Accepted: 12/09/2016] [Indexed: 06/06/2023]
Abstract
Mini-hydrocyclones were applied to separate the fine rare earth particles from the suspensions. The effects of the flow rate, split ratio, and feed concentration on the total separation efficiency and grade separation efficiency were studied. The combined effects of the flow rate (1200-1600L/h), split ratio (20-60%) and concentration (0.6-1.0wt%) on the total separation efficiency in mini-hydrocyclones were investigated using a response surface methodology. The optimum operating parameters for a total separation efficiency of 92.5% were: feed flow rate=1406L/h, split ratio=20%, and feed concentration=1wt%.
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Affiliation(s)
- Jian-Feng Yu
- School of Mechanical Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China; Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment & Technology, Wuxi, Jiangsu 214122, China.
| | - Jian Fu
- School of Mechanical Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China; Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment & Technology, Wuxi, Jiangsu 214122, China
| | - Hao Cheng
- School of Mechanical Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China; Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment & Technology, Wuxi, Jiangsu 214122, China
| | - Zhengwei Cui
- School of Mechanical Engineering, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China; Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment & Technology, Wuxi, Jiangsu 214122, China
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Subhedar PB, Gogate PR. Ultrasound assisted intensification of biodiesel production using enzymatic interesterification. Ultrason Sonochem 2016; 29:67-75. [PMID: 26584986 DOI: 10.1016/j.ultsonch.2015.09.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [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: 06/30/2015] [Revised: 09/05/2015] [Accepted: 09/06/2015] [Indexed: 06/05/2023]
Abstract
Ultrasound assisted intensification of synthesis of biodiesel from waste cooking oil using methyl acetate and immobilized lipase obtained from Thermomyces lanuginosus (Lipozyme TLIM) as a catalyst has been investigated in the present work. The reaction has also been investigated using the conventional approach based on stirring so as to establish the beneficial effects obtained due to the use of ultrasound. Effect of operating conditions such as reactant molar ratio (oil and methyl acetate), temperature and enzyme loading on the yield of biodiesel has been investigated. Optimum conditions for the conventional approach (without ultrasound) were established as reactant molar ratio of 1:12 (oil:methyl acetate), enzyme loading of 6% (w/v), temperature of 40 °C and reaction time of 24 h and under these conditions, 90.1% biodiesel yield was obtained. The optimum conditions for the ultrasound assisted approach were oil to methyl acetate molar ratio of 1:9, enzyme loading of 3% (w/v), and reaction time of 3 h and the biodiesel yield obtained under these conditions was 96.1%. Use of ultrasound resulted in significant reduction in the reaction time with higher yields and lower requirement of the enzyme loading. The obtained results have clearly established that ultrasound assisted interesterification was a fast and efficient approach for biodiesel production giving significant benefits, which can help in reducing the costs of production. Reusability studies for the enzyme were also performed but it was observed that reuse of the catalyst under the optimum experimental condition resulted in reduced enzyme activity and biodiesel yield.
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Affiliation(s)
- Preeti B Subhedar
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India
| | - Parag R Gogate
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India.
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Gogate PR, Prajapat AL. Depolymerization using sonochemical reactors: A critical review. Ultrason Sonochem 2015; 27:480-494. [PMID: 26186870 DOI: 10.1016/j.ultsonch.2015.06.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [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: 04/05/2015] [Revised: 06/19/2015] [Accepted: 06/19/2015] [Indexed: 05/12/2023]
Abstract
Ultrasonic irradiation has been proposed as a novel approach for degradation of polymer compounds, especially considering the fact that the reduction in the molecular weight (also the intrinsic viscosity) is simply by splitting the most susceptible chemical bond without causing any changes in the chemical nature. An overview of the application of ultrasound for the polymer degradation has been presented in this work, discussing the mechanism of degradation, kinetic modeling, effect of operating parameters and the type of reactors generally used for depolymerization. The effect of important operating parameters such as initial polymer concentration, presence of functional groups in the polymer chain, reaction volume, initial molecular weight, temperature, operating frequency, power dissipation and use of process intensifying additives have been discussed also giving guidelines about selection of the optimum parameters. It has been observed that the low concentrations and higher power dissipation (till an optimum) are favorable resulting in higher extents of degradation. Typically low frequency is recommended but for the case of water soluble polymers, higher frequencies would also give similar results due to the dominant action of chemical effects of cavitation. It has been demonstrated that the alkyl group substituent also affects the degradation rate of polymer. An overview of degradation using combined approach based on ultrasound and additives with comparison with individual approach has also been presented. It has been observed that the main contributing factor for the synergy of the combined approach is the selection of optimum loading of additives. Overall, it has been observed that efficient polymer degradation can be achieved using combined process based on the use of ultrasound.
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Affiliation(s)
- Parag R Gogate
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India.
| | - Amrutlal L Prajapat
- Chemical Engineering Department, Institute of Chemical Technology, Matunga, Mumbai 400 019, India
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Sun L, Müller B, Westerholm M, Schnürer A. Syntrophic acetate oxidation in industrial CSTR biogas digesters. J Biotechnol 2013; 171:39-44. [PMID: 24333792 DOI: 10.1016/j.jbiotec.2013.11.016] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 11/21/2013] [Accepted: 11/25/2013] [Indexed: 10/25/2022]
Abstract
The extent of syntrophic acetate oxidation (SAO) and the levels of known SAO bacteria and acetate- and hydrogen-consuming methanogens were determined in sludge from 13 commercial biogas production plants. Results from these measurements were statistically related to the prevailing operating conditions, through partial least squares (PLS) analysis. This revealed that high abundance of microorganisms involved in SAO was positively correlated with relatively low abundance of aceticlastic methanogens and high concentrations of free ammonia (>160 mg/L) and volatile fatty acids (VFA). Temperature was identified as another influencing factor for the population structure of the syntrophic acetate oxidising bacteria (SAOB). Overall, there was a high abundance of SAOB in the different digesters despite differences in their operating parameters, indicating that SAOB are an enduring and important component of biogas-producing consortia.
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Affiliation(s)
- Li Sun
- Uppsala Biocenter, Department of Microbiology, Swedish University of Agricultural Sciences, Box 7025, SE 750 07 Uppsala, Sweden.
| | - Bettina Müller
- Uppsala Biocenter, Department of Microbiology, Swedish University of Agricultural Sciences, Box 7025, SE 750 07 Uppsala, Sweden.
| | - Maria Westerholm
- Uppsala Biocenter, Department of Microbiology, Swedish University of Agricultural Sciences, Box 7025, SE 750 07 Uppsala, Sweden.
| | - Anna Schnürer
- Uppsala Biocenter, Department of Microbiology, Swedish University of Agricultural Sciences, Box 7025, SE 750 07 Uppsala, Sweden.
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Saleem M, Krammer G, Tahir MS. The effect of operating conditions on resistance parameters of filter media and limestone dust cake for uniformly loaded needle felts in a pilot scale test facility at ambient conditions. POWDER TECHNOL 2012; 228:100-107. [PMID: 24415803 PMCID: PMC3886362 DOI: 10.1016/j.powtec.2012.05.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2011] [Revised: 04/30/2012] [Accepted: 05/04/2012] [Indexed: 11/28/2022]
Abstract
Resistance parameters are essential for the prediction of pressure drop in bag filters. The reported values for limestone dust differ in magnitude and also depend on operating parameters. In this work, experimental data is provided from a pilot scale pulse-jet regenerated bag filter test facility for three types of needle felts using air and limestone dust at ambient conditions. Results reveal that specific resistance of filter media is independent of velocity while the specific resistance of filter cake increases linearly with filtration velocity. Residual pressure drop is almost constant, independent of upper pressure drop limit. The cake resistance at constant velocity fits to a second degree polynomial whereas it increases linearly with the velocity. A linear relation is reported here for all the cases. The resistance of filter cake decreases at higher upper pressure drop limit.
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Affiliation(s)
- Mahmood Saleem
- Institut of Chemical Engineering and Technology, University of the Punjab, Quaid-i-Azam Campus, Lahore-54590, Pakistan ; Graz University of Technology, Graz, Austria
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Saleem M, Krammer G, Khan RU, Tahir MS. Influence of operating parameters on cake formation in pilot scale pulse-jet bag filter. POWDER TECHNOL 2012; 224:28-35. [PMID: 24415802 PMCID: PMC3886375 DOI: 10.1016/j.powtec.2012.02.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 02/04/2012] [Accepted: 02/11/2012] [Indexed: 11/30/2022]
Abstract
Bag filters are commonly used for fine particles removal in off-gas purification. There dust laden gas pervades through permeable filter media starting at a lower pressure drop limit leaving dust (called filter cake) on the filter media. The filter cakeformation is influenced by many factors including filtration velocity, dust concentration, pressure drop limits, and filter media resistance. Effect of the stated parameters is investigated experimentally in a pilot scale pulse-jet bag filter test facility where lime stone dust is separated from air at ambient conditions. Results reveal that filtration velocity significantly affects filter pressure drop as well as cake properties; cake density and specific cake resistance. Cake density is slightly affected by dust concentration. Specific resistance of filter cake increases with velocity, slightly affected by dust concentration, changes inversely with the upper pressure drop limit and decreases over a prolonged use (aging). Specific resistance of filter media is independent of upper pressure drop limit and increases linearly over a prolonged use.
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Affiliation(s)
- Mahmood Saleem
- Institute of Chemical Engineering and Technology, University of the Punjab, Quaid-i-Azam Campus, 54590- Lahore, Pakistan ; Graz University of Technology, Graz, Austria
| | | | - Rafi Ullah Khan
- Institute of Chemical Engineering and Technology, University of the Punjab, Quaid-i-Azam Campus, 54590- Lahore, Pakistan
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