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Li H, Zeng Q, Zan F, Lin S, Hao T. In situ coagulation-electrochemical oxidation of leachate concentrate: A key role of cathodes. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 16:100267. [PMID: 37065009 PMCID: PMC10091031 DOI: 10.1016/j.ese.2023.100267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 02/25/2023] [Accepted: 03/13/2023] [Indexed: 06/19/2023]
Abstract
To efficiently remove organic and inorganic pollutants from leachate concentrate, an in situ coagulation-electrochemical oxidation (CO-EO) system was proposed using Ti/Ti4O7 anode and Al cathode, coupling the "super-Faradaic" dissolution of Al. The system was evaluated in terms of the removal efficiencies of organics, nutrients, and metals, and the underlying cathodic mechanisms were investigated compared with the Ti/RuO2-IrO2 and graphite cathode systems. After a 3-h treatment, the Al-cathode system removed 89.0% of COD and 36.3% of total nitrogen (TN). The TN removal was primarily ascribed to the oxidation of both ammonia and organic-N to N2. In comparison, the Al-cathode system achieved 3-10-fold total phosphorus (TP) (62.6%) and metal removals (>80%) than Ti/RuO2-IrO2 and graphite systems. The increased removals of TP and metals were ascribed to the in situ coagulation of Al(OH)3, hydroxide precipitation, and electrodeposition. With the reduced scaling on the Al cathode surface, the formation of Al3+ and electrified Al(OH)3 lessened the requirement for cathode cleaning and increased the bulk conductivity, resulting in increased instantaneous current production (38.9%) and operating cost efficiencies (48.3 kWh kgCOD -1). The present study indicated that the in situ CO-EO process could be potentially used for treating persistent wastewater containing high levels of organic and inorganic ions.
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Affiliation(s)
- Huankai Li
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China
| | - Qian Zeng
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Feixiang Zan
- School of Environmental Science and Engineering, Low-Carbon Water Environment Technology Center (HUST-SUKE), Huazhong University of Science and Technology, Wuhan, China
| | - Sen Lin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Tianwei Hao
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau, China
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2
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Pan Z, Xu S, Xin H, Yuan Y, Xu R, Wang P, Yan X, Fan X, Song C, Wang T. High performance polypyrrole coated carbon-based electrocatalytic membrane for organic contaminants removal from aqueous solution. J Colloid Interface Sci 2022; 626:283-295. [DOI: 10.1016/j.jcis.2022.06.138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/19/2022] [Accepted: 06/25/2022] [Indexed: 11/15/2022]
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Kumar A, Barbhuiya NH, Singh SP. Magnéli phase titanium sub-oxides synthesis, fabrication and its application for environmental remediation: Current status and prospect. CHEMOSPHERE 2022; 307:135878. [PMID: 35932919 DOI: 10.1016/j.chemosphere.2022.135878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 07/24/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
Sub-stoichiometric titanium oxide, also called titanium suboxides (TSO), had been a focus of research for many decades with a chemical composition of TinO2n-1 (n ≥ 1). It has a unique oxygen-deficient crystal structure which provides it an outstanding electrical conductivity and high corrosion resistance similar to ceramic materials. High electrical conductivity and ability to sustain in adverse media make these phases a point of attention for researchers in energy storage and environmental remediation applications. The Magnéli phase-based reactive electroconductive membranes (REM) and electrodes have demonstrated the electrochemical oxidation of pollutants in the water in flow-through and flow by configuration. Additionally, it has also shown its potential for visible light photochemical degradation as well. This review attempts to summarize state of the art in various Magnéli phases materials synthesis routes and their electrochemical and photochemical ability for environmental application. The manuscript introduces the Magnéli phase, its crystal structure, and catalytic properties, followed by the recent development in synthesis methods from diverse titanium sources, notably TiO2 through thermal reduction. The various fabrication methods for Magnéli phase-base REMs and electrodes have also been summarized. Furthermore, the article discussed the environmental remediations via electrochemical and photochemical advanced oxidation processes. Additionally, the hybrid technology with REMs and electrodes is used to counter membrane biofouling and develop electrochemical sensing devices for the pollutants. The Magnéli phase materials have a bright future for both electrochemical and photochemical advanced oxidation of emerging contaminants in water and wastewater treatment.
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Affiliation(s)
- Ashish Kumar
- Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Najmul H Barbhuiya
- Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Mumbai, 400076, India
| | - Swatantra P Singh
- Environmental Science and Engineering Department (ESED), Indian Institute of Technology Bombay, Mumbai, 400076, India; Centre for Research in Nanotechnology & Science (CRNTS), Indian Institute of Technology Bombay, Mumbai, 400076, India; Interdisciplinary Program in Climate Studies, Indian Institute of Technology Bombay, Mumbai, 400076, India.
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4
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Electrochemical oxidation of lamivudine using graphene oxide and Yb co-modified PbO2 electrodes: characterization, influencing factors and degradation mechanisms. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121856] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Dong Y, Wu H, Yang F, Gray S. Cost and efficiency perspectives of ceramic membranes for water treatment. WATER RESEARCH 2022; 220:118629. [PMID: 35609431 DOI: 10.1016/j.watres.2022.118629] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/12/2022] [Accepted: 05/15/2022] [Indexed: 06/15/2023]
Abstract
More robust ceramic membranes with tailorable structures and functions are increasingly employed for water treatment, particularly in some harsh applications for their ultra-long service lifespan due to their high mechanical, structural, chemical and thermal stability and anti-fouling properties. Decreasing cost and enhancing efficiency are two key but quite challenging application-oriented issues for broader and larger-scale engineering application of current ceramic membranes, and are required to make ceramic membranes a highly efficient and economic water treatment technique. In this review, we critically discuss these two significant concerns of both cost and efficiency for water treatment ceramic membranes, focusing on an overview of various advanced strategies and mechanism insights. A brief up-to-date discussion is first introduced about recent developments of ceramic membranes covering the major advances of novel membranes and applications. Then some promising strategies for decreasing the cost of ceramic membranes are discussed, including membrane material cost and processing cost. To fully address the issue of moderate efficiency with single separation function, valuable and considerable insights are provided into recent major progress and mechanism understandings in application with other unit processes, such as advanced oxidation and electrochemistry techniques, to significantly enhance treatment efficiency. Subsequently, a review of recent ceramic membrane applications emphasizing harsh operating environments is presented, such as oil-water separation, saline water, refractory organic and emerging contaminant wastewater treatment. Finally, engineering application, conclusions, and future perspectives of ceramic membrane for water treatment applications are critically discussed offering new insight based on understanding the issues of cost and efficiency.
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Affiliation(s)
- Yingchao Dong
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
| | - Hui Wu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Fenglin Yang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Stephen Gray
- Institute for Sustainable Industries & Liveable Cities, Victoria University, PO Box 14428, Melbourne, Australia
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6
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Progress in Preparation and Application of Titanium Sub-Oxides Electrode in Electrocatalytic Degradation for Wastewater Treatment. Catalysts 2022. [DOI: 10.3390/catal12060618] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
To achieve low-carbon and sustainable development it is imperative to explore water treatment technologies in a carbon-neutral model. Because of its advantages of high efficiency, low consumption, and no secondary pollution, electrocatalytic oxidation technology has attracted increasing attention in tackling the challenges of organic wastewater treatment. The performance of an electrocatalytic oxidation system depends mainly on the properties of electrodes materials. Compared with the instability of graphite electrodes, the high expenditure of noble metal electrodes and boron-doped diamond electrodes, and the hidden dangers of titanium-based metal oxide electrodes, a titanium sub-oxide material has been characterized as an ideal choice of anode material due to its unique crystal and electronic structure, including high conductivity, decent catalytic activity, intense physical and chemical stability, corrosion resistance, low cost, and long service life, etc. This paper systematically reviews the electrode preparation technology of Magnéli phase titanium sub-oxide and its research progress in the electrochemical advanced oxidation treatment of organic wastewater in recent years, with technical difficulties highlighted. Future research directions are further proposed in process optimization, material modification, and application expansion. It is worth noting that Magnéli phase titanium sub-oxides have played very important roles in organic degradation. There is no doubt that titanium sub-oxides will become indispensable materials in the future.
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Saha P, Wang Y, Moradi M, Brüninghoff R, Moussavi G, Mei B, Mul G, H. M. Rijnaarts H, Bruning H. Advanced oxidation processes for removal of organics from cooling tower blowdown: Efficiencies and evaluation of chlorinated species. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119537] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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8
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Enhanced organic wastewater treatment performance in electrochemical filtration process of coal-based carbon membrane via the simple Fe2+ addition. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119418] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Messaoudi M, Douma M, Tijani N, Messaoudi L. Study of the permeability of tubular mineral membranes: application to wastewater treatment. Heliyon 2021; 7:e06837. [PMID: 33981894 PMCID: PMC8082269 DOI: 10.1016/j.heliyon.2021.e06837] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/08/2021] [Accepted: 04/13/2021] [Indexed: 10/24/2022] Open
Abstract
This research work opens up the possibility of developing tubular mineral membranes from Moroccan clay powders and their use in water permeability tests and wastewater treatment. The aim is to show the possibility of using clay as a low-cost raw material for the production of ceramic membranes with high mechanical and chemical performances. In a first step, we developed ceramic membranes by extruding a prepared plastic paste with the addition of an optimized amount of wood powder as organic matter (OM) to improve the porosity characteristics of the final products after firing. Several parameters are controlled such as the chemical and mineralogical composition of the starting clay powder, the granulometry and the final sintering temperature. The effect of sintering temperature in the range from 800 to 1000 °C, and OM addition (5, 10, 15wt%) on tubular membrane properties such as mechanical and chemical resistance, porosity and permeability were investigated. It was found that the incorporation of OM in the raw clay enhance the pore volume and the permeate flux but it was also accompanied by a decrease in mechanical strength. The membrane sintered at 1000 °C with 15wt% of OM is considered as optimized membrane and it was applied for the second stage of this work. This stage concerns the treatment of wastewater from a thermal complex located 12 km south of the city of Meknes, Morocco, through a treatment by a biological disk microstation. The filtrate obtained then undergoes tangential filtration by the membranes elaborated and optimized following the evolution of the pollution parameters. Based on physicochemical and biological analyses of wastewater after treatment by the coupled system, the membranes obtained have a good permeability and an excellent pollution removal performance.
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Affiliation(s)
- Mohammed Messaoudi
- Laboratory of Materials, Membranes and Nanotechnology, Department of Chemistry, Faculty of Sciences, Moulay Ismail University, PB 11201, Zitoune, Meknes, Morocco
| | - Mohamed Douma
- Laboratory of Materials, Membranes and Nanotechnology, Department of Chemistry, Faculty of Sciences, Moulay Ismail University, PB 11201, Zitoune, Meknes, Morocco
| | - Najib Tijani
- Laboratory of Materials, Membranes and Nanotechnology, Department of Chemistry, Faculty of Sciences, Moulay Ismail University, PB 11201, Zitoune, Meknes, Morocco
| | - Lahcen Messaoudi
- Laboratory of Materials, Membranes and Nanotechnology, Department of Chemistry, Faculty of Sciences, Moulay Ismail University, PB 11201, Zitoune, Meknes, Morocco
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Liu L, Li K, Zhao S, Wang J, Lan H, Wang J. The effects of electrophoresis, bubbles and electroosmosis for conductive membrane performance in the electro-filtration process. J Memb Sci 2021. [DOI: 10.1016/j.memsci.2020.118955] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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11
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He Y, Zhang P, Huang H, Wang X, Chen B, Guo Z, Lin H. Electrochemical degradation of herbicide diuron on flow-through electrochemical reactor and CFD hydrodynamics simulation. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.117284] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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12
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Wang X, Sun M, Zhao Y, Wang C, Ma W, Wong MS, Elimelech M. In Situ Electrochemical Generation of Reactive Chlorine Species for Efficient Ultrafiltration Membrane Self-Cleaning. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:6997-7007. [PMID: 32356975 DOI: 10.1021/acs.est.0c01590] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Reactive membranes based on hydroxyl radical generation are hindered by the need for chemical dosing and complicated module and material design. Herein, we utilize an electrochemical approach featuring in situ generation of reactive (radical) chlorine species (RCS) through anodization of chloride ions for membrane self-cleaning. A hybridized carbon nanotube (CNT)-functionalized ceramic membrane (h-CNT/CM), possessing high hydrophilicity, permeability, and conductivity, was fabricated. Using carbamazepine (CBZ) as a probe, we confirmed the presence of RCS in the electrified h-CNT/CM. The rapid and complete degradation of CBZ in a single-pass ultrafiltration indicates a high localized RCS concentration within the three-dimensional porous CNT interwoven layer. We further demonstrate that the electrogeneration of RCS is a critical prestep for free chlorine (HClO and ClO-) formation. The self-cleaning efficiency of the membrane after fouling with a model organic foulant (alginate) was assessed using an electrified cross-flow membrane filtration system. The fouled h-CNT/CM exhibits a near complete water flux recovery following a short (1 min) self-cleaning with an applied voltage of 3 or 4 V and feed solutions of 100 or 10 mM sodium chloride, respectively. Considering the superior performance of the RCS-mediated self-cleaning compared to conventional membrane chemical cleaning using sodium hypochlorite, our results exemplify an effective strategy for in situ electrogeneration of RCS to achieve a highly efficient membrane self-cleaning.
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Affiliation(s)
- Xiaoxiong Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Meng Sun
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Yumeng Zhao
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Chi Wang
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- School of Environment, Northeast Normal University, Changchun 130024, China
| | - Wen Ma
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
| | - Michael S Wong
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Houston, Texas 77005, United States
| | - Menachem Elimelech
- Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06520-8286, United States
- Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment (NEWT), Houston, Texas 77005, United States
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Ayode Otitoju T, Ugochukwu Okoye P, Chen G, Li Y, Onyeka Okoye M, Li S. Advanced ceramic components: Materials, fabrication, and applications. J IND ENG CHEM 2020. [DOI: 10.1016/j.jiec.2020.02.002] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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14
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Hu C, Li M, Sun J, Liu R, Liu H, Qu J. NOM fouling resistance in response to electric field during electro-ultrafiltration: Significance of molecular polarity and weight. J Colloid Interface Sci 2019; 539:11-18. [DOI: 10.1016/j.jcis.2018.12.048] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 11/29/2018] [Accepted: 12/12/2018] [Indexed: 12/16/2022]
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15
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One step co-sintering process for low-cost fly ash based ceramic microfiltration membrane in oil-in-water emulsion treatment. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2018.08.040] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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16
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Trellu C, Chaplin BP, Coetsier C, Esmilaire R, Cerneaux S, Causserand C, Cretin M. Electro-oxidation of organic pollutants by reactive electrochemical membranes. CHEMOSPHERE 2018; 208:159-175. [PMID: 29864707 DOI: 10.1016/j.chemosphere.2018.05.026] [Citation(s) in RCA: 103] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/18/2018] [Accepted: 05/02/2018] [Indexed: 06/08/2023]
Abstract
Electro-oxidation processes are promising options for the removal of organic pollutants from water. The major appeal of these technologies is the possibility to avoid the addition of chemical reagents. However, a major limitation is associated with slow mass transfer that reduces the efficiency and hinders the potential for large-scale application of these technologies. Therefore, improving the reactor configuration is currently one of the most important areas for research and development. The recent development of a reactive electrochemical membrane (REM) as a flow-through electrode has proven to be a breakthrough innovation, leading to both high electrochemically active surface area and convection-enhanced mass transport of pollutants. This review summarizes the current state of the art on REMs for the electro-oxidation of organic compounds by anodic oxidation. Specific focuses on the electroactive surface area, mass transport, reactivity, fouling and stability of REMs are included. Recent advances in the development of sub-stoichiometric titanium oxide REMs as anodes have been made. These electrodes possess high electrical conductivity, reactivity (generation of •OH), chemical/electrochemical stability, and suitable pore structure that allows for efficient mass transport. Further development of REMs strongly relies on the development of materials with suitable physico-chemical characteristics that produce electrodes with efficient mass transport properties, high electroactive surface area, high reactivity and long-term stability.
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Affiliation(s)
- Clément Trellu
- Institut Européen des Membranes, IEM - UMR 5635, ENSCM, CNRS, Univ Montpellier, Montpellier, France; Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France.
| | - Brian P Chaplin
- Department of Chemical Engineering, University of Illinois at Chicago, 810 S. Clinton Street, Chicago, IL 60607, USA
| | - Clémence Coetsier
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Roseline Esmilaire
- Institut Européen des Membranes, IEM - UMR 5635, ENSCM, CNRS, Univ Montpellier, Montpellier, France
| | - Sophie Cerneaux
- Institut Européen des Membranes, IEM - UMR 5635, ENSCM, CNRS, Univ Montpellier, Montpellier, France
| | - Christel Causserand
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Marc Cretin
- Institut Européen des Membranes, IEM - UMR 5635, ENSCM, CNRS, Univ Montpellier, Montpellier, France
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Zheng J, Yan K, Wu Z, Liu M, Wang Z. Effective Removal of Sulfanilic Acid From Water Using a Low-Pressure Electrochemical RuO 2-TiO 2@Ti/PVDF Composite Membrane. Front Chem 2018; 6:395. [PMID: 30238003 PMCID: PMC6135927 DOI: 10.3389/fchem.2018.00395] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2018] [Accepted: 08/15/2018] [Indexed: 12/12/2022] Open
Abstract
Removal of sulfanilic acid (SA) from water is an urgent but still challenging task. Herein, we developed a low pressure electrochemical membrane filtration (EMF) system for SA decontamination using RuO2-TiO2@Ti/PVDF composite membrane to serve as not only a filter but also an anode. Results showed that efficient removal of SA was achieved in this EMF system. At a charging voltage of 1.5 V and a electrolyte concentration of 15 mM, flow-through operation with a hydraulic retention time (HRT) of 2 h led to a high SA removal efficiency (80.4%), as expected from the improved contact reaction of this compound with ROS present at the anode surface. Cyclic voltammetry (CV) analysis indicated that the direct anodic oxidation played a minor role in SA degradation. Electron spin resonance (ESR) spectra demonstrated the production of •OH in the EMF system. Compared to the cathodic polarization, anodic generated ROS was more likely responsible for SA removal. Scavenging tests suggested that adsorbed •OH on the anode (>•OH) played a dominant role in SA degradation, while O2•- was an important intermediate oxidant which mediated the production of •OH. The calculated mineralization current efficiency (MCE) of the flow-through operated system 29.3% with this value much higher than that of the flow-by mode (5.1%). As a consequence, flow-through operation contributed to efficient oxidation of SA toward CO2 and nontoxic carboxylic acids accounting for 71.2% of initial C. These results demonstrate the potential of the EMF system to be used as an effective technology for water decontamination.
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Affiliation(s)
- Junjian Zheng
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Kaili Yan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Zhichao Wu
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
| | - Mingxian Liu
- School of Chemical Science and Engineering, Tongji University, Shanghai, China
| | - Zhiwei Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Tongji University, Shanghai, China
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Dynamic cross-flow electro-Fenton process coupled to anodic oxidation for wastewater treatment: Application to the degradation of acetaminophen. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2018.03.063] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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