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Wang C, Zhou S, Wang X, Tan W, Feng X. Photocatalytic activation of sulfite by maghemite (γ-Fe 2O 3) for iohexol degradation and alleviation effect of HCO 3- on water acidification. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 346:123557. [PMID: 38355082 DOI: 10.1016/j.envpol.2024.123557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/27/2024] [Accepted: 02/10/2024] [Indexed: 02/16/2024]
Abstract
Photo-catalyzing sulfite (S(IV)) for the generation of sulfate radical (SO4•-) has emerged as a novel advanced oxidation process (AOP) recently. However, both the potential of soil minerals as effective photocatalysts and the process of water acidification due to S(IV) oxidation have been overlooked. Herein, maghemite (γ-Fe2O3), a typical soil iron oxide with excellent photocatalytic reactivity like hematite and magnetic-collectible property like magnetite, was successfully used to activate S(IV) for iohexol degradation under visible light irradiation. As a result, 91.3% of iohexol was eliminated within 15 min at 0.1 g/L maghemite and 0.5 mM S(IV) under neutral conditions. The influencing factors, including initial pH, catalyst dosage, S(IV) amount, co-existing substances and water matrix, were systematically investigated. The maghemite/S(IV)/vis system exhibited superior performance in iohexol degradation at a wide pH range (3-10). It was found that the released proton via S(IV) oxidation led to severe water acidification. Interestingly, a low dose of HCO3- could evidently resist water acidification with little influence on iohexol elimination. Radical quenching experiments and electron spin resonance (ESR) analysis confirmed that SO4•-, •OH and •O2- were involved in iohexol abatement with SO4•- being the dominant reactive species. Compared with hydrogen peroxide, persulfate and peroxymonosulfate, the established maghemite/S(IV)/vis system achieved much more remarkable degradation performance. Furthermore, the reactivity of the catalyst was not obviously reduced even after 10 runs of reaction. This study expands the application of soil iron oxide mineral in S(IV) activation in water treatment and proposes an approach to regulate water acidification in S(IV)-based AOP.
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Affiliation(s)
- Cheng Wang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs of the People's Republic of China, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Shuijing Zhou
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs of the People's Republic of China, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Xiaoming Wang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs of the People's Republic of China, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Wenfeng Tan
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs of the People's Republic of China, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Xionghan Feng
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs of the People's Republic of China, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
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Liu M, Chen H, Xiao P, Ji H. Sulfite activation by Jahn-Teller-driven oxygen vacancies Cu-Mn composite oxide for chlortetracycline degradation. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132658. [PMID: 37793256 DOI: 10.1016/j.jhazmat.2023.132658] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/23/2023] [Accepted: 09/26/2023] [Indexed: 10/06/2023]
Abstract
Copper-manganese composite metal oxides (CuMnOy) were prepared by hydrolysis-driven oxidation-reduction method and used to activate sulfite to degrade chlortetracycline hydrochloride (CTC) for the first time. The Jahn-Teller ions Mn3+ and Cu2+ exist in CuMnOy, which form a solid electric charge transport redox system and ensure the continuous generation of reactive oxygen species (ROS). Through the systematic study of the experimental parameters such as sulfite concentration, catalyst metal molar ratio, catalyst amounts and initial pH, the optimal degradation rate of CTC could reach 91.74% within 10 min and 94.46% after 30 min. The major reactive radicals were determined by radical quenching experiments and electron paramagnetic resonance (EPR) trapping techniques, and it was confirmed that SO4•- and •O2- played a nonnegligible role in the process of degrading CTC. Density functional theory (DFT) calculations show that higher Fukui indices (f- and f0) of CTC sites are more vulnerable to free radical attack. CuMnOy has low CTC degradation intermediate toxicity, high catalytic performance, good anti-interference ability, reusability and stability, and possesses decent application potential in the actual water treatment field.
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Affiliation(s)
- Mingyi Liu
- College of Forestry, Northeast Forestry University, Harbin 150040, China; Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, China
| | - Hanchun Chen
- Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, China
| | - Pengfei Xiao
- College of Forestry, Northeast Forestry University, Harbin 150040, China.
| | - Haodong Ji
- Eco-environment and Resource Efficiency Research Laboratory, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen, Guangdong 518055, China.
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Xu W, Zhang Y, Zhang X, Xu X, Wang Q. One stone, two birds: A Cu-S cluster as a laccase-mimicking nanozyme and sulfite activator for phenol remediation in marine environments. JOURNAL OF HAZARDOUS MATERIALS 2023; 457:131776. [PMID: 37285787 DOI: 10.1016/j.jhazmat.2023.131776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/29/2023] [Accepted: 06/02/2023] [Indexed: 06/09/2023]
Abstract
Phenols are infamous pollutants in marine environments and present a grave danger to human health, which makes their efficient detection and removal serious issues. Colorimetry is a simple method for detecting phenols in water because phenols can be oxidized by natural laccase and generate a brown product. However, high cost and poor stability impede the wide-spread implementation of natural laccase in phenol detection. To reverse this adverse situation, a nanoscale Cu-S cluster, Cu4(MPPM)4 (Cu4S4, MPPM = 2-mercapto-5-n-propylpyrimidine), is synthesized. As a stable and inexpensive nanozyme, Cu4S4 shows excellent laccase-mimicking activity and prompts the oxidation of phenols. This characteristic makes Cu4S4 a perfect option for phenol detection with colorimetry. In addition, Cu4S4 also exhibits sulfite activation properties. It can degrade phenols and other pollutants with advanced oxidation processes (AOPs). Theoretical calculations show good laccase-mimicking and sulfite activation properties originating from appropriate interactions between Cu4S4 and substrates. We anticipate that the phenol detection and degradation characteristics of Cu4S4 make it a promising material to be used for practical phenol remediation in water environments.
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Affiliation(s)
- Wei Xu
- Department of Chemistry, College of Science, Northeastern University, Shenyang 110819 Liaoning, China
| | - Yifei Zhang
- Department of Chemistry, College of Science, Northeastern University, Shenyang 110819 Liaoning, China
| | - Xia Zhang
- Department of Chemistry, College of Science, Northeastern University, Shenyang 110819 Liaoning, China
| | - Xinxin Xu
- Department of Chemistry, College of Science, Northeastern University, Shenyang 110819 Liaoning, China.
| | - Qiang Wang
- Key Laboratory of Electromagnetic Processing of Materials, MOE, Northeastern University, Shenyang 110819 Liaoning, China.
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4
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Ibrahim AO, Huang Y, Liu H, Mustapha NA. On-site generation of reactive oxidative radicals from dithionite treated oxic soil slurry. ENVIRONMENTAL TECHNOLOGY 2023; 44:1751-1762. [PMID: 34842053 DOI: 10.1080/09593330.2021.2012267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
Whereas dithionite has been extensively used as a reducing agent in soil and sediment remediation, here, we demonstrate that it can be used as a potential source of oxidizing radical in oxic soils with potential application in organic pollutant remediation. Benzoic acid was used as a probe compound and the generation of its oxidative product para-hydroxybenzoic acid (p-HBA) was detected to quantify the production of oxidative radicals (ROS). By increasing the dithionite concentration from 2.5-10 Mm, the accumulated P-HBA concentration in 120 min increased from 15.0-27 µM. Whereas, above 10 mM, the p-HBA concentration decreased due to radical scavenging. Increasing soil dosage from 2.5-15 g/100 mL the accumulated p-HBA amount increased from 22.8-33.7 µM. Temperature 25-35 oC and pH 6.2-7.5 were favoured for p-HBA generation. Furthermore, we investigated the roles of different active intermediates in the reaction system and proposed the mechanism behind the ROS genearation. This study suggested that dithionite can be used as an active reagent for advanced oxidation remediation in oxic soil medium.
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Affiliation(s)
- Abdullateef Omeiza Ibrahim
- State Key Laboratory of Biogeology and Environmental Geology and School of Environmental Studies, China University of Geosciences, Wuhan, People's Republic of China
| | - Yao Huang
- State Key Laboratory of Biogeology and Environmental Geology and School of Environmental Studies, China University of Geosciences, Wuhan, People's Republic of China
| | - Hui Liu
- State Key Laboratory of Biogeology and Environmental Geology and School of Environmental Studies, China University of Geosciences, Wuhan, People's Republic of China
| | - Nasiru Abba Mustapha
- State Key Laboratory of Biogeology and Environmental Geology and School of Environmental Studies, China University of Geosciences, Wuhan, People's Republic of China
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Xu W, Zhang X, Xu X, Chen J, Wang Q. Guest Molecule Insertion-Optimized d-Band Center Position in MoS 2 with Improved Sulfite Activation Ability Inspired by Sulfite Oxidase. ACS APPLIED MATERIALS & INTERFACES 2023; 15:13042-13051. [PMID: 36867742 DOI: 10.1021/acsami.2c22151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
As a prospective member in the family of advanced oxidation processes (AOPs), heterogeneous sulfite activation shows low cost and high safety for poisonous organic pollutants' degradation. To obtain an efficient sulfite activator, sulfite oxidase (SuOx), a molybdenum-based enzyme that can prompt oxidation and activation of sulfite, inspired us greatly. Based on the structure of SuOx, MoS2/BPE (BPE = 1, 2-bis-(4-pyridyl)-ethylene) is synthesized successfully. In MoS2/BPE, the BPE molecule is inserted between the MoS2 layers as a pillar and the N atom links with Mo4+ directly. MoS2/BPE shows excellent SuOx mimic activity. Theoretical calculation implies that BPE insertion optimizes the d-band center position of MoS2/BPE, which regulates the interaction between MoS2 and *SO42-. This prompts •SO4- generation and organic pollutants' degradation. At pH 7.0, its tetracycline degradation efficiency achieved is 93.9% in 30 min. Furthermore, its sulfite activation ability also endows MoS2/BPE with excellent antibiofouling performance because •SO4- can kill the microorganisms in water effectively. This work develops a new sulfite activator based on SuOx. The connection between structure and SuOx mimic activity and sulfite activation ability is clarified in detail.
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Affiliation(s)
- Wei Xu
- Department of Chemistry, College of Science, Northeastern University, Shenyang 110819, Liaoning, China
| | - Xia Zhang
- Department of Chemistry, College of Science, Northeastern University, Shenyang 110819, Liaoning, China
| | - Xinxin Xu
- Department of Chemistry, College of Science, Northeastern University, Shenyang 110819, Liaoning, China
- Institute for Frontier Technologies of Low-Carbon Steelmaking, Northeastern University, Shenyang 110819, Liaoning, China
| | - Jin Chen
- Key Laboratory of Electromagnetic Processing of Materials, MOE, Northeastern University, Shenyang 110819, Liaoning, China
| | - Qiang Wang
- Key Laboratory of Electromagnetic Processing of Materials, MOE, Northeastern University, Shenyang 110819, Liaoning, China
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Zhao G, Ding J, Ren J, Zhao Q, Fan H, Wang K, Gao Q, Chen X, Long M. Treasuring industrial sulfur by-products: A review on add-value to reductive sulfide and sulfite for contaminant removal and hydrogen production. JOURNAL OF HAZARDOUS MATERIALS 2022; 438:129462. [PMID: 35792429 DOI: 10.1016/j.jhazmat.2022.129462] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 06/07/2022] [Accepted: 06/23/2022] [Indexed: 06/15/2023]
Abstract
Reductive sulfur-containing by-products (S-BPs) released from industrial process mainly exist in the simple form of sulfide and sulfite. In this study, recent advances to remove and make full use of reductive S-BPs to achieve efficient contaminant removal and hydrogen production are critically reviewed. Sulfide, serves as both reductant and nucleophile, can form intermediates with the catalyst surface functional group through chemical interaction, efficiently promoting the catalytic reduction process to remove contaminants. Sulfite assisted catalytic process could be classified to the advanced reduction processes (ARPs) and advanced oxidation processes (AOPs), mainly depending on the presence of dissolved oxygen (DO) in the solution. During ARPs, sulfite could generate reductive active species including hydrated electron (eaq-), hydrogen radical (H·), and sulfite radical (SO3•-) under the irradiation of UV light, leading to the efficient reduction removal of a variety of contaminants. During AOPs, sulfite could first produce SO3•- under the action of the catalyst or energy, initiating a series of reactions to produce oxysulfur radicals. Various contaminants could be effectively removed under the role of these oxidizing active species. Sulfides and sulfites could also be removed along with promoting hydrogen production via photocatalytic and electrocatalytic processes. Besides, the present limitations and the prospects for future practical applications of the process with these S-BPs are proposed. Overall, this review gives a comprehensive summary and aims to provide new insights and thoughts in promoting contaminant removal and hydrogen production through taking full advantage of reductive S-BPs.
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Affiliation(s)
- Guanshu Zhao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jing Ding
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Jiayi Ren
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qingliang Zhao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Haojun Fan
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Kun Wang
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qingwei Gao
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xueqi Chen
- State Key Laboratory of Urban Water Resources and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Mingce Long
- School of Environmental Science and Engineering, Key Laboratory of Thin Film and Microfabrication Technology (Ministry of Education), Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
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7
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Gu Y, Song Z, Dong Z, Sun F, Jiang C, Qi J. Efficient degradation and deiodination of iopamidol by UV/sulfite process: Assessment of typical process parameters and transformation paths. ENVIRONMENT INTERNATIONAL 2022; 167:107383. [PMID: 35952467 DOI: 10.1016/j.envint.2022.107383] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 06/17/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Iopamidol (IPM) is widely used in medical clinical examination and treatment and has immeasurable harm to the ecological environment. The combination of UV and sulfite (UV/sulfite) process was developed to degrade IPM in this study. In contrast to that almost no removal of IPM was observed under sulfite reduction alone, the UV/sulfite process could efficiently reductively degrade IPM with the observed rate constant (kobs) of 2.08 min-1, which was nearly 4 times that of UV irradiation alone. The major active species in the UV/sulfite process were identified as hydrated electrons (eaq-) by employing active species scavengers. The influence of the initial pH, sulfite dosage, IPM concentration, UV intensity and common water matrix were evaluated. The degradation of IPM reached nearly 100% within only 2.5 min at pH 9, and kobs increased at higher initial sulfite dosages and greater UV intensities. HCO3- had a limited effect on the degradation of IPM, while humic acid (HA) was found to be a strong inhibitor in the UV/sulfite process. With the synergistic action of UV/sulfite, most of the iodine in IPM was found to release in the form of iodide ions (up to approximately 98%), and a few formed iodide-containing organic compounds, reducing significantly the toxicity of degradation products. Under direct UV irradiation and free radical reduction (mainly eaq-), 15 transformation intermediates of IPM were produced by amide hydrolysis, deiodination, hydroxyl radical addition and hydrogen abstraction reactions, in which free radical attack accounted for the main part. Consequently, the UV/sulfite process has a strong potential for IPM degradation in aquatic environments.
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Affiliation(s)
- Yurong Gu
- School of Material and Environmental Engineering, Shenzhen Polytechnic, Shenzhen 518055, China
| | - Zi Song
- School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Zijun Dong
- School of Civil and Traffic Engineering, Shenzhen University, Shenzhen 518055, China.
| | - Feiyun Sun
- School of Civil and Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China; State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Chengchun Jiang
- School of Material and Environmental Engineering, Shenzhen Polytechnic, Shenzhen 518055, China
| | - Jikun Qi
- School of Civil and Environmental Engineering, Shenyang Jianzhu University, Shenyang 110168, China
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Hu CY, Zhu YY, Xu B, Zhang TY, Lin YL, Xiong C, Wang QB, Huang DD, Xu L. Fe3O4 catalytic ozonation of iohexol degradation in the presence of 1-hydroxybenzotriazole: Performance, transformation mechanism, and pathways. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.120810] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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9
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Liu Y, Zhao Y, Wang J. Activation of peroxydisulfate by a novel Cu 0-Cu 2O@CNTs composite for 2, 4-dichlorophenol degradation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:141883. [PMID: 32919314 DOI: 10.1016/j.scitotenv.2020.141883] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Revised: 07/18/2020] [Accepted: 08/20/2020] [Indexed: 06/11/2023]
Abstract
In this study, a novel Cu0-Cu2O@CNTs composite was synthesized, characterized and applied to activate peroxydisulfate (PDS) for the degradation of 2, 4-dichlorophenol (2,4-DCP) in contaminated lake water. The results indicated that Cu0-Cu2O@CNTs can effectively activate PDS to produce O2•- radical, which has high selectivity to degrade organic pollutants in actual contaminated water. The efficiency of 2,4-DCP degradation and mineralization was 99.27% and 66.90%, respectively under the optimal condition. In the presence of Cl-, HCO3- and natural organic matters (NOMs) or in real wastewater containing 2,4-DCP, Cu0-Cu2O@CNTs/PDS system had a good selectivity for 2,4-DCP degradation. O2•- was the dominant reactive species in Cu0-Cu2O@CNTs/PDS system for 2,4-DCP degradation. The possible degradation pathway of 2,4-DCP was proposed. It was concluded that Cu0-Cu2O@CNTs composite could overcome the shortcomings of PDS activation by Cu0 and Cu2O alone, such as low activating capability of Cu0 and instability of Cu2O, which was high efficient for activating PDS. Cu0-Cu2O@CNTs composite can be used as an efficient catalyst to activate PDS for the degradation of toxic organic pollutants in water and wastewater.
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Affiliation(s)
- Yong Liu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, China
| | - Yang Zhao
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu 610066, China; Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084, China
| | - Jianlong Wang
- Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing 100084, China.
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Thamaraiselvan C, Thakur AK, Gupta A, Arnusch CJ. Electrochemical Removal of Organic and Inorganic Pollutants Using Robust Laser-Induced Graphene Membranes. ACS APPLIED MATERIALS & INTERFACES 2021; 13:1452-1462. [PMID: 33390015 DOI: 10.1021/acsami.0c18358] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The removal of emerging environmental pollutants in water and wastewater is essential for high drinking water quality or for discharge to the environment. Electrochemical treatment is a promising technology shown to degrade undesirable organic compounds or metals via oxidation and reduction, and carbon-based electrodes have been reported. Here, we fabricated a robust, porous laser-induced graphene (LIG) electrode on a commercial water treatment membrane using the multilasing technique and demonstrated the electrochemical removal of iohexol, an iodine contrast compound, and chromium(VI), a highly toxic heavy metal ion. Multiple lasing resulted in a more ordered graphitic lattice, a more physically robust carbon layer, and a 3-4-fold higher electrical conductivity. These properties ultimately led to a more efficient electrochemical process, and the optimized LIG electrodes showed a higher hydrogen peroxide (H2O2) generation. At 3 V, 90% of Cr(VI) was removed after 6 h and reached >95% removal after 8 h at pH 2. Cr(VI) was mainly reduced to Cr(III), with small amounts of Cr(I) and Cr(0), which were partially deposited on the electrode membrane surface, confirmed with X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy analysis. Under the same conditions, 50% of iohexol was degraded after 6 h and the transformation products (TPs) were identified using ultra-performance liquid chromatography coupled with mass spectroscopy. A total of seven main intermediates were identified including deiodinated TPs (m/z = 695, 570, and 443), probably occurring via three transformation pathways including oxidative deiodination, amide hydrolysis, and deacetylation. The electrical energy costs calculated for the removal of 2 mg L-1 Cr(VI) was ∼$0.08/m3 in this system. Taken together, the porous LIG electrodes might be utilized for electrochemical removal of emerging contaminants in multiple applications because they can be rapidly formed on flexible polymer substrates at low cost.
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Affiliation(s)
- Chidambaram Thamaraiselvan
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben Gurion 8499000, Israel
| | - Amit K Thakur
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben Gurion 8499000, Israel
| | - Abhishek Gupta
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben Gurion 8499000, Israel
| | - Christopher J Arnusch
- Department of Desalination and Water Treatment, Zuckerberg Institute for Water Research, The Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede-Boqer Campus, Midreshet Ben Gurion 8499000, Israel
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Zhao X, Wu W, Jing G, Zhou Z. Activation of sulfite autoxidation with CuFe 2O 4 prepared by MOF-templated method for abatement of organic contaminants. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 260:114038. [PMID: 31995773 DOI: 10.1016/j.envpol.2020.114038] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/30/2019] [Accepted: 01/21/2020] [Indexed: 06/10/2023]
Abstract
Copper ferrite (denoted as CuFe2O4MOF), prepared via a complexation reaction to obtain bimetal-organic frameworks (Cu/Fe bi-MOFs), followed by a combustion process to remove the MOF template, is employed as a heterogeneous activator to promote sulfite autoxidation for the removal of organic contaminants. At pH 8.0, more than 80% of the recalcitrant organic contaminant iohexol (10 μM) can be removed within 2 min by the activation of sulfite (500 μM) with CuFe2O4MOF (0.1 g L-1). CuFe2O4MOF exhibits more pronounced catalytic activity in accelerating sulfite autoxidation for iohexol abatement compared to that fabricated by hydrothermal and sol-gel combustion methods. Radical quenching studies suggest that the sulfate radical (SO4•-) is the main reactive species responsible for iohexol abatement. The performance of CuFe2O4MOF/sulfite for iohexol abatement can be affected by several critical influencing factors, including the solution pH and the presence of humic acid, Cl-, and HCO3-. The effect of the ionic strength and the results of the attenuated total reflectance-Fourier transform infrared (ATR-FTIR) analysis indicate that sulfite autoxidation in the presence of CuFe2O4MOF involves an inner-sphere interaction with the surface Cu(II) sites of CuFe2O4MOF. X-ray photoelectron spectroscopy (XPS) characterization suggests that the surface Cu(II)-Cu(I)-Cu(II) redox cycle is responsible for efficient SO4•- production from sulfite. Overall, CuFe2O4MOF can be considered an alternative activator for sulfite autoxidation for potential application in the treatment of organic-contaminated water.
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Affiliation(s)
- Xiaodan Zhao
- College of Chemical Engineering, Huaqiao University, Xiamen, 361021, China
| | - Wenjing Wu
- College of Chemical Engineering, Huaqiao University, Xiamen, 361021, China
| | - Guohua Jing
- College of Chemical Engineering, Huaqiao University, Xiamen, 361021, China
| | - Zuoming Zhou
- College of Chemical Engineering, Huaqiao University, Xiamen, 361021, China.
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