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Song Z, He J, Kouzehkanan SMT, Oh TS, Olshansky Y, Duin EC, Carroll KC, Wang D. Enhanced sorption and destruction of PFAS by biochar-enabled advanced reduction process. CHEMOSPHERE 2024; 363:142760. [PMID: 38969229 DOI: 10.1016/j.chemosphere.2024.142760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Revised: 07/02/2024] [Accepted: 07/02/2024] [Indexed: 07/07/2024]
Abstract
The biochar-enabled advanced reduction process (ARP) was developed for enhanced sorption (by biochar) and destruction of PFAS (by ARP) in water. First, the biochar (BC) was functionalized by iron oxide (Fe3O4), zero valent iron (ZVI), and chitosan (chi) to produce four biochars (BC, Fe3O4-BC, ZVI-chi-BC, and chi-BC) with improved physicochemical properties (e.g., specific surface area, pore structure, hydrophobicity, and surface functional groups). Batch sorption experimental results revealed that compared to unmodified biochar, all modified biochars showed greater sorption efficiency, and the chi-BC performed the best for PFAS sorption. The chi-BC was then selected to facilitate reductive destruction and defluorination of PFAS in water by ARP in the UV-sulfite system. Adding chi-BC in UV-sulfite ARP system significantly enhanced both degradation and defluorination efficiencies of PFAS (up to ∼100% degradation and ∼85% defluorination efficiencies). Radical analysis using electron paramagnetic resonance (EPR) spectroscopy showed that sulfite radicals dominated at neutral pH (7.0), while hydrated electrons (eaq-) were abundant at higher pH (11) for the efficient destruction of PFAS in the ARP system. Our findings elucidate the synergies of biochar and ARP in enhancing PFAS sorption and degradation, providing new insights into PFAS reductive destruction and defluorination by different reducing radical species at varying pH conditions.
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Affiliation(s)
- Ziteng Song
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | - Jianzhou He
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA
| | | | - Tae-Sik Oh
- Department of Chemical Engineering, Auburn University, Auburn, AL, 36849, USA
| | - Yaniv Olshansky
- Department of Crop, Soil, and Environmental Sciences, Auburn, AL, 36849, USA
| | - Evert C Duin
- Department of Chemistry and Biochemistry, Auburn, AL, 36849, USA
| | - Kenneth C Carroll
- Department of Plant and Environmental Sciences, New Mexico State University, NM, 88003, USA
| | - Dengjun Wang
- School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, Auburn, AL, 36849, USA.
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Pan Y, Zhang F, Tan W, Feng X. New insight into wastewater treatment by activation of sulfite with humic acid under visible light irradiation. WATER RESEARCH 2024; 258:121773. [PMID: 38796910 DOI: 10.1016/j.watres.2024.121773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 04/07/2024] [Accepted: 05/12/2024] [Indexed: 05/29/2024]
Abstract
Sulfite (S(IV)), as an alternative to persulfate, has demonstrated its cost-effectiveness and environmentally friendly nature, garnering increasing attention in Advanced Oxidation Processes (AOPs). Dissolved organic matter (DOM) commonly occurred in diverse environments and was often regarded as an interfering factor in sulfite-based AOPs. However, less attention has been paid to the promotion of the activation of sulfite by excited DOM, which could produce various reactive intermediates. The study focused on the activation of sulfite using visible light (VL) - excited humic acid (HA) to efficiently degrade many common organic pollutants, which was better than peroxydisulfate (PDS) and peroxymonosulfate (PMS) systems. Quenching experiments and electron paramagnetic resonance (EPR) analysis revealed that the triplet states of HA (3HA*) activated sulfite through energy transfer, resulting in the production of SO4·-, O2·-, and 1O2. The most significant active species found in the degradation of roxarsone (ROX) was 1O2, which was a non-radical pathway and exhibits high selectivity for pollutant degradation. This non-radical pathway was not commonly observed in traditional sulfite-based AOPs. Additionally, the coexistence of various inorganic anions, such as NO3-, Cl-, SO42-, CO32-, and PO43-, had little effect on the degradation of ROX. Furthermore, DOM from different natural water demonstrated efficient activation of S(IV) under light conditions, opening up new possibilities for applying sulfite-based advanced oxidation to the remediation of organic pollution in diverse sites and water bodies. In summary, this research offered promising insights into the potential application of sulfite-based AOPs, facilitated by photo-excited HA, as a new strategy for efficiently degrading organic pollutants in various environmental settings.
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Affiliation(s)
- Yanting Pan
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Wuhan 430070, China; Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Feng Zhang
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Wuhan 430070, China; Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Wenfeng Tan
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Wuhan 430070, China; Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China
| | - Xionghan Feng
- State Environmental Protection Key Laboratory of Soil Health and Green Remediation, Wuhan 430070, China; Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan 430070, China.
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Vahidi-Kolur R, Yazdanbakhsh A, Hosseini SA, Sheikhmohammadi A. Photoreduction of atrazine from aqueous solution using sulfite/iodide/UV process, degradation, kinetics and by-products pathway. Sci Rep 2024; 14:5217. [PMID: 38433251 PMCID: PMC10909853 DOI: 10.1038/s41598-024-55585-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 02/26/2024] [Indexed: 03/05/2024] Open
Abstract
Due to its widespread use in agriculture, atrazine has entered aquatic environments and thus poses potential risks to public health. Therefore, researchers have done many studies to remove it. Advanced reduction process (ARP) is an emerging technology for degrading organic contaminants from aqueous solutions. This study was aimed at evaluating the degradation of atrazine via sulfite/iodide/UV process. The best performance (96% of atrazine degradation) was observed in the neutral pH at 60 min of reaction time, with atrazine concentration of 10 mg/L and concentration of sulfite and iodide of 1 mM. The kinetic study revealed that the removal of atrazine was matched with the pseudo-first-order model. Results have shown that reduction induced by e aq - and direct photolysis dominated the degradation of atrazine. The presence of anions (Cl - , CO 3 2 - and SO 4 2 - ) did not have a significant effect on the degradation efficiency. In optimal conditions, COD and TOC removal efficiency were obtained at 32% and 4%, respectively. Atrazine degradation intermediates were generated by de-chlorination, hydroxylation, de-alkylation, and oxidation reactions. Overall, this research illustrated that Sulfite/iodide/UV process could be a promising approach for atrazine removal and similar contaminants from aqueous solutions.
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Affiliation(s)
- Robabeh Vahidi-Kolur
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ahmadreza Yazdanbakhsh
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
- Workplace Health Promotion Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
| | - Seyed Arman Hosseini
- Department of Environmental Health Engineering, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Amir Sheikhmohammadi
- Environmental Health Engineering, Khoy University of Medical Sciences, Khoy, West Azerbaijan, Iran
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Park J, Bandstra JZ, Tratnyek PG, Harvey OR, Bae JS, Lee G. Modeling the Role in pH on Contaminant Sequestration by Zerovalent Metals: Chromate Reduction by Zerovalent Magnesium. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:2564-2573. [PMID: 38278139 DOI: 10.1021/acs.est.3c08367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2024]
Abstract
The role of pH in sequestration of Cr(VI) by zerovalent magnesium (ZVMg) was characterized by global fitting of a kinetic model to time-series data from unbuffered batch experiments with varying initial pH values. At initial pH values ranging from 2.0 to 6.8, ZVMg (0.5 g/L) completely reduced Cr(VI) (18.1 μM) within 24 h, during which time pH rapidly increased to a plateau value of ∼10. Time-series correlation analysis of the pH and aqueous Cr(VI), Cr(III), and Mg(II) concentration data suggested that these conditions are controlled by combinations of reactions (involving Mg0 oxidative dissolution and Cr(VI) sequestration) that evolve over the time course of each experiment. Since this is also likely to occur during any engineering applications of ZVMg for remediation, we developed a kinetic model for dynamic pH changes coupled with ZVMg corrosion processes. Using this model, the synchronous changes in Cr(VI) and Mg(II) concentrations were fully predicted based on the Langmuir-Hinshelwood kinetics and transition-state theory, respectively. The reactivity of ZVMg was different in two pH regimes that were pH-dependent at pH < 4 and pH-independent at the higher pH. This contrasting pH effect could be ascribed to the shift of the primary oxidant of ZVMg from H+ to H2O at the lower and higher pH regimes, respectively.
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Affiliation(s)
- Jaeseon Park
- Department of Earth System Sciences, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
| | - Joel Z Bandstra
- Department of Mathematics, Engineering, and Computer Science, Saint Francis University, P.O. Box 600, Loretto, Pennsylvania 15940, United States
| | - Paul G Tratnyek
- OHSU-PSU School of Public Health, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, United States
| | - Omar R Harvey
- Department of Geological Sciences, Texas Christian University, Fort Worth, Texas 76129, United States
| | - Jong-Seong Bae
- Division of High-Technology Materials Research, Busan Center, Korea Basic Science Institute, 30 Gwahaksandan 1-ro 60, Gangseo-gu, Busan 618-230, Republic of Korea
| | - Giehyeon Lee
- Department of Earth System Sciences, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
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Zhang J, Li J, Tang W, Liu X, Yang C, Ma J. Highly efficient reduction of bromate by vacuum UV/sulfite system. CHEMOSPHERE 2024; 349:140875. [PMID: 38065260 DOI: 10.1016/j.chemosphere.2023.140875] [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: 08/24/2023] [Revised: 11/03/2023] [Accepted: 11/30/2023] [Indexed: 01/10/2024]
Abstract
Bromate (BrO3-), a worldwide regulated by-product after ozone disinfection, is often detected in bromide-containing water, and has a strict limit of 10 μg L-1 in potable water. BrO3- degradation by advanced reduction processes (ARPs) has gained much attention because of efficient removal and easy integration with ultraviolet disinfection (UV at 254 nm). In the vacuum UV (VUV, 185/254 nm)/sulfite system, the elimination kinetics of BrO3- increased by 9-fold and 15-fold comparing with VUV alone and UV/sulfite system. This study further demonstrated the hydrated electron (eaq-) works as the dominant species in BrO3- degradation in alkaline solution, while in the acidic solution the H• became a secondary reactive species besides eaq-. Hence, the influences of pH, sulfite concentration, dissolved gas and water matrix on effectiveness of degradation kinetics of BrO3- was explored in details. With increasing pH, the proportion of SO32- species increased and even became the major ones, which also correlated well with the kobs (min-1) of BrO3- degradation. The stability of eaq- also climbs with increasing pH, while that of H• drops significantly. Higher sulfite dosage favored a more rapid degradation of BrO3-. The presence of dissolved oxygen inhibited BrO3- removal due to the scavenging effect of O2 toward eaq- and transformed VUV/sulfite-based ARP to an advanced oxidation process (AOP), which was ineffective for BrO3- removal. BrO3- removal was inhibited to varying degrees after anions (e.g., bicarbonate (HCO3-), chloride (Cl-), nitrate (NO3-)) and humic acid (HA) being added.
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Affiliation(s)
- Jing Zhang
- School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China.
| | - Junjie Li
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Weijie Tang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Xin Liu
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Chun Yang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China.
| | - Jun Ma
- School of Environment, Harbin Institute of Technology, Harbin, 150090, PR China
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Zhu T, Li S, Li L, Tao C. A new perspective on predicting the reaction rate constants of hydrated electrons for organic contaminants: Exploring molecular structure characterization methods and ambient conditions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166316. [PMID: 37591396 DOI: 10.1016/j.scitotenv.2023.166316] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/26/2023] [Accepted: 08/12/2023] [Indexed: 08/19/2023]
Abstract
Hydrated electrons (eaq-) exhibit rapid degradation of diverse persistent organic contaminants (OCs) and hold great promise as a formidable reducing agent in water treatment. However, the diverse structures of compounds exert different influences on the second-order rate constant of hydrated electron reactions (keaq-), while the same OCs demonstrate notable discrepancies in keaq- values across different pH levels. This study aims to develop machine learning (ML) models that can effectively simulate the intricate reaction kinetics between eaq- and OCs. Furthermore, the introduction of the pH variable enables a comprehensive investigation into the impact of ambient conditions on this process, thereby improving the practicality of the model. A dataset encompassing 701 keaq- values derived from 351 peer-reviewed publications was compiled. To comprehensively investigate compound properties, this study introduced molecular descriptor (MD), molecular fingerprint (MF), and the integration of both (MD + MF) as model variables. Furthermore, 60 sets of predictive models were established utilizing two variable screening methodologies (MLR and RF) and ten prominent algorithms. Through statistical parameter analysis, it was determined that descriptors combined with MD and MF, the RF screening method, and the symbolism algorithm exhibited the best predictive efficacy. Importantly, the combination of descriptor models exhibited significantly superior performance compared to individual MF and MD models. Notably, the optimal model, denoted as RF - (MF + MD) - LGB, exhibited highly satisfactory predictive results (R2tra = 0.967, Q2tra = 0.840, R2ext = 0.761). The mechanistic explanation study based on Shapley Additive Explanations (SHAP) values further elucidated the crucial influences of polarity, pH, molecular weight, electronegativity, carbon-carbon double bonds, and molecular topology on the degradation of OCs by eaq-. The proposed modeling approach, particularly the integration of MF and MD, alongside the introduction of pH, may furnish innovative ideas for advanced reduction or oxidation processes (ARPs/AOPs) and machine learning applications in other domains.
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Affiliation(s)
- Tengyi Zhu
- School of Environmental Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China.
| | - Shuyin Li
- School of Environmental Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Lili Li
- School of Environmental Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
| | - Cuicui Tao
- School of Environmental Science and Engineering, Yangzhou University, Yangzhou 225127, Jiangsu, China
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7
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Vatankhah H, Anderson RH, Ghosh R, Willey J, Leeson A. A review of innovative approaches for onsite management of PFAS-impacted investigation derived waste. WATER RESEARCH 2023; 247:120769. [PMID: 37931356 DOI: 10.1016/j.watres.2023.120769] [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: 09/10/2023] [Revised: 10/19/2023] [Accepted: 10/20/2023] [Indexed: 11/08/2023]
Abstract
The historic use of aqueous film-forming foam (AFFF) has led to widespread detection of per- and polyfluoroalkyl substance (PFAS) in groundwater, soils, sediments, drinking water, wastewater, and receiving aquatic systems throughout the United States (U.S.). Prior to any remediation activities, in order to identify the PFAS-impacted source zones and select the optimum management approach, extensive site investigations need to be conducted. These site investigations have resulted in the generation of considerable amount of investigation-derived waste (IDW) which predominantly consists of well purging water and drill fluid, equipment washing residue, soil, drill cuttings, and residues from the destruction of asphalt and concrete surfaces. IDW is often impacted by varying levels of PFAS which poses a substantial challenge concerning disposal to prevent potential mobilization of PFAS, logistical complexities, and increasing requirement for storage as a result of accumulation of the associated wastes. The distinct features of IDW involve the intermittent generation of waste, substantial volume of waste produced, and the critical demand for onsite management. This article critically focuses on innovative technologies and approaches employed for onsite treatment and management of PFAS-impacted IDW. The overall objective of this study centers on developing and deploying end-of-life treatment technology systems capable of facilitating unrestricted disposal, discharge, and/or IDW reuse on-site, thereby reducing spatial footprints and mobilization time.
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Affiliation(s)
- Hooman Vatankhah
- Strategic Environmental Research and Development Program and the Environmental Security Technology Certification Program, Arlington, VA, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA; Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO, USA.
| | | | | | | | - Andrea Leeson
- Strategic Environmental Research and Development Program and the Environmental Security Technology Certification Program, Arlington, VA, USA
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Mundhenke TF, Bhat AP, Pomerantz WCK, Arnold WA. Photolysis Products of Fluorinated Pharmaceuticals: A Combined Fluorine Nuclear Magnetic Resonance Spectroscopy and Mass Spectrometry Approach. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2023. [PMID: 37861370 DOI: 10.1002/etc.5773] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/26/2023] [Accepted: 10/17/2023] [Indexed: 10/21/2023]
Abstract
The aqueous photolysis of four pharmaceuticals with varying fluorinated functional groups was assessed under neutral, alkaline, advanced oxidation, and advanced reduction conditions with varying light sources. Solar simulator quantum yields were 2.21 × 10-1 mol Ei-1 for enrofloxacin, 9.36 × 10-3 mol Ei-1 for voriconazole, and 1.49 × 10-2 mol Ei-1 for flecainide. Florfenicol direct photolysis was slow, taking 150 h for three degradation half-lives. Bimolecular rate constants between pharmaceuticals and hydroxyl radicals were 109 to 1010 M-1 s-1 . Using a combined quantitative fluorine nuclear magnetic resonance spectroscopy (19 F-NMR) and mass spectrometry approach, fluorine mass balances and photolysis product structures were elucidated. Enrofloxacin formed a variety of short-lived fluorinated intermediates that retained the aryl F motif. Extended photolysis time led to complete aryl F mineralization to fluoride. The aliphatic F moiety on florfenicol was also mineralized to fluoride, but the resulting product was a known antibiotic (thiamphenicol). For voriconazole, the two aryl Fs contributed more to fluoride production compared with the heteroaromatic F, indicating higher stability of the heteroaromatic F motif. The two aliphatic CF3 moieties in the flecainide structure remained intact under all conditions, further supporting the stability of these moieties found in per- and polyfluoroalkyl substances under a variety of conditions. The advanced treatment conditions generating hydroxyl radicals or hydrated electrons accelerated the degradation, but not the defluorination, of flecainide. The combination of 19 F-NMR and mass spectrometry proved powerful in allowing identification of fluorinated products and verifying the functional groups present in the intermediates and products. The results found in the present study will aid in the understanding of which fluorinated functional groups should be incorporated into pharmaceuticals to ensure organofluorine byproducts are not formed in the environment and help determine the water-treatment processes that effectively remove specific pharmaceuticals and more generally fluorinated motifs. Environ Toxicol Chem 2023;00:1-12. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Affiliation(s)
- Thomas F Mundhenke
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota, Minneapolis, Minnesota, USA
| | - Akash P Bhat
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota, Minneapolis, Minnesota, USA
| | | | - William A Arnold
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota, Minneapolis, Minnesota, USA
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9
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Zhang L, Liu Y, Wang J. Selective and effective oxidation of ammonium to dinitrogen in MgO/Na 2SO 3/K 2S 2O 8 system. CHEMOSPHERE 2023; 325:138401. [PMID: 36925013 DOI: 10.1016/j.chemosphere.2023.138401] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 03/07/2023] [Accepted: 03/12/2023] [Indexed: 06/18/2023]
Abstract
The oxidation of ammonium (NH4+) to dinitrogen (N2) with high selectivity and high efficiency is still a challenge. Herein, a novel sunlight induced persulfate (PS)-based AOPs process (MgO/Na2SO3/PS/hv) was proposed by introducing solid base (MgO) and hydrated electron (eaq-), to selectively oxidize NH4+ to N2, with high selectivity and high efficiency at a wide range of pH value. The deprotonation of NH4+ into NH3 by MgO and the generation of •OH and SO4-• by PS activation were responsible for the high efficiency of NH4+ oxidation. The buffering capacity provided by MgO to proton released from PS activation made the NH4+ oxidation possible at a wide pH range. The eaq- from the Na2SO3/hv process was the main active specie to reduce NO2-and NO3- (NOx-) into N2, responsible for high N2 selectivity of NH4+ oxidation. 100% NH4+ could be oxidized within 30 min, and N2 selectivity exceeded 96% at the initial pH range of 3-11 and the initial concentration of NH4+ of 30 mg N/L. This work could offer an efficient AOPs process for selective NH4+ oxidation, which is promising for the chemical denitrification of wastewater ….
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Affiliation(s)
- Le Zhang
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China
| | - Yong Liu
- College of Chemistry and Materials Science, Sichuan Normal University, Chengdu, 610066, China
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing, 100084, China.
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10
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Cardoso IMF, Pinto da Silva L, Esteves da Silva JCG. Nanomaterial-Based Advanced Oxidation/Reduction Processes for the Degradation of PFAS. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13101668. [PMID: 37242085 DOI: 10.3390/nano13101668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Revised: 05/11/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023]
Abstract
This review focuses on a critical analysis of nanocatalysts for advanced reductive processes (ARPs) and oxidation processes (AOPs) designed for the degradation of poly/perfluoroalkyl substances (PFAS) in water. Ozone, ultraviolet and photocatalyzed ARPs and/or AOPs are the basic treatment technologies. Besides the review of the nanomaterials with greater potential as catalysts for advanced processes of PFAS in water, the perspectives for their future development, considering sustainability, are discussed. Moreover, a brief analysis of the current state of the art of ARPs and AOPs for the treatment of PFAS in water is presented.
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Affiliation(s)
- Inês M F Cardoso
- Chemistry Research Unit (CIQUP), Institute of Molecular Sciences (IMS), Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto (FCUP), Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
| | - Luís Pinto da Silva
- Chemistry Research Unit (CIQUP), Institute of Molecular Sciences (IMS), Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto (FCUP), Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
| | - Joaquim C G Esteves da Silva
- Chemistry Research Unit (CIQUP), Institute of Molecular Sciences (IMS), Department of Geosciences, Environment and Territorial Planning, Faculty of Sciences, University of Porto (FCUP), Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
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11
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Chen X, Wang J, Wu H, Zhu Z, Zhou J, Guo H. Trade-off effect of dissolved organic matter on degradation and transformation of micropollutants: A review in water decontamination. JOURNAL OF HAZARDOUS MATERIALS 2023; 450:130996. [PMID: 36867904 DOI: 10.1016/j.jhazmat.2023.130996] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 01/24/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
The degradation of micropollutants by various treatments is commonly affected by the ubiquitous dissolved organic matter (DOM) in the water environment. To optimize the operating conditions and decomposition efficiency, it is necessary to consider the impacts of DOM. DOM exhibits varied behaviors in diverse treatments, including permanganate oxidation, solar/ultraviolet photolysis, advanced oxidation processes, advanced reduction process, and enzyme biological treatments. Besides, the different sources (i.e., terrestrial and aquatic, etc) of DOM, and operational circumstances (i.e., concentration and pH) fluctuate different transformation efficiency of micropollutants in water. However, so far, systematic explanations and summaries of relevant research and mechanism are rare. This paper reviewed the "trade-off" performances and the corresponding mechanisms of DOM in the elimination of micropollutants, and summarized the similarities and differences for the dual roles of DOM in each of the aforementioned treatments. Inhibition mechanisms typically include radical scavenging, UV attenuation, competition effect, enzyme inactivation, reaction between DOM and micropollutants, and intermediates reduction. Facilitation mechanisms include the generation of reactive species, complexation/stabilization, cross-coupling with pollutants, and electron shuttle. Moreover, electron-drawing groups (i.e., quinones, ketones functional groups) and electron-supplying groups (i.e., phenols) in the DOM are the main contributors to its trade-off effect.
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Affiliation(s)
- Xingyu Chen
- MOE Key Laboratory of Deep Earth Science and Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Jingquan Wang
- MOE Key Laboratory of Deep Earth Science and Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Han Wu
- MOE Key Laboratory of Deep Earth Science and Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Zhuoyu Zhu
- MOE Key Laboratory of Deep Earth Science and Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Jianfei Zhou
- National Engineering Research Center of Clean Technology in Leather Industry, Sichuan University, Chengdu 610065, China.
| | - Hongguang Guo
- MOE Key Laboratory of Deep Earth Science and Engineering, College of Architecture and Environment, Sichuan University, Chengdu 610065, China; Yibin Industrial Technology Research Institute of Sichuan University, Yibin 644000, China.
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12
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Li Y, Lv L, Yang L, He L, Chen Y, Wu L, Zhang Z. Boosting degradation and defluorination efficiencies of PFBS in a vacuum-ultraviolet/S(Ⅳ) process with iodide involvement. CHEMOSPHERE 2023; 313:137531. [PMID: 36509188 DOI: 10.1016/j.chemosphere.2022.137531] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/08/2022] [Accepted: 12/09/2022] [Indexed: 06/17/2023]
Abstract
Perfluorobutane sulfonate (PFBS) is considered to be a promising alternative of perfluorooctane sulfonates (PFOS), while it is also hazardous. The UV/S (Ⅳ) system has been confirmed to be effective for PFOS removal from water, while it is inefficient for PFBS decomposition. A hybrid vacuum-ultraviolet (VUV)/S (Ⅳ)/KI process was investigated for the degradation of PFBS in aqueous solution. With KI involvement, the degradation rate of PFBS was boosted from 1.8802 μg h-1 up to 3.5818 μg h-1 in the VUV/S (Ⅳ) process. Alkaline conditions significantly increased the degradation efficiency of PFBS, which can be explained that S (Ⅳ) was dominated by SO32- rather than HSO3- and H2SO3 in alkaline conditions. Cl-, HCO3-, NO3-, NO2-, and HA would inhibit the performance of the VUV/S (Ⅳ)/KI process via various reactions. In addition, the toxicity of PFBS was significantly reduced by the VUV/S (Ⅳ)/KI process. Even in actual waters, the VUV/S (Ⅳ)/KI process also presented a satisfying performance in the degradation of PFBS.
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Affiliation(s)
- Yulong Li
- Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Lixin Lv
- Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Lie Yang
- Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China.
| | - Liuyang He
- Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Yulin Chen
- Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Li Wu
- Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China
| | - Zulin Zhang
- Hubei Key Laboratory of Mineral Resources Processing and Environment, School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan, 430070, PR China; The James Hutton Institute, Craigiebuckler, Aberdeen, ABI5 8QH, UK
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13
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Song W, Li M, Xu S, Wang Z, Li J, Zhang X, Qiu W, Wang Z, Song Q, Bhatt K, Fu C. Performance and mechanisms for tetrabromobisphenol A efficient degradation in a novel homogeneous advanced treatment based on S 2O 42- activated by Fe 3. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 316:120579. [PMID: 36336186 DOI: 10.1016/j.envpol.2022.120579] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 09/24/2022] [Accepted: 10/31/2022] [Indexed: 06/16/2023]
Abstract
Tetrabromobisphenol A (TBBPA), a representative brominated flame retardant (BFR), generally could be debrominated and degraded effectively in photolysis systems with the high energy consumption. In this study, the novel sulfate radical (SO4•-) generation resource of dithionite (S2O42-), activated by the common transition metal of Fe3+, has been applied for establishing an innovative homogeneous advance treatment system for BFR treatment in water. When coupling Fe3+ with S2O42-, TBBPA degradation efficiency could be remarkably improved from 38.7% to 93.8% with the debromination and mineralization efficiency of 83.9% and 18.5% in 60 min, respectively. The primary reactive species also have been identified as SO3•-, SO4•- and •OH responsible for TBBPA treatment and the contributions of SO4•- and •OH have been calculated as 43.8% and 28.4% for TBBPA degradation, respectively. In Fe3+/S2O42- system, TBBPA was effectively degraded in a wide initial pH range (3.0-9.0), whose activation energy was calculated as 32.01 kJ mol-1. Due to the only operation of reagents dosing, the energy consumption and cost could be decreasing significantly without any light energy input and reaction conditions (e.g., pH and dissolved oxygen) adjustment compared with the general photolysis process. Moreover, some possible degradation approaches of TBBPA also have been proposed via GC-MS including debromination, hydroxylation, methylation, and mineralization in Fe3+/S2O42- system. And these probable degradation pathways also have been confirmed with the decreased Gibbs free energy (ΔG) based on density functional theory (DFT). This study has revealed that it was promising of Fe3+/S2O42- system for BFRs degradation and detoxification efficiently through the simple operation and mild condtions.
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Affiliation(s)
- Wei Song
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Mu Li
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China; Shenzhen Environmental Science and New Energy Laboratory, Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen, China
| | - Sen Xu
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Zhuoyue Wang
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China; School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Ji Li
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China
| | - Xiaolei Zhang
- School of Civil and Environmental Engineering, Shenzhen Key Laboratory of Water Resource Application and Environmental Pollution Control, Harbin Institute of Technology (Shenzhen), Shenzhen, 518055, China.
| | - Wenhui Qiu
- School of Public Health and Emergency Management, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Zhihong Wang
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Qi Song
- Henan Medscience Pharmaceuticals Co., Ltd., Zhumadian, 463000, China
| | - Kalpana Bhatt
- Department of Food Science, Purdue University, West Lafayette, IN, 47907, USA
| | - Caixia Fu
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
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14
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So HL, Wang L, Liu J, Chu W, Li T, Abdelhaleem A. Insights into the degradation of diphenhydramine - An emerging SARS-CoV-2 medicine by UV/Sulfite. Sep Purif Technol 2022; 303:122193. [PMID: 36168647 PMCID: PMC9502506 DOI: 10.1016/j.seppur.2022.122193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Revised: 09/18/2022] [Accepted: 09/19/2022] [Indexed: 11/28/2022]
Abstract
As Diphenhydramine (DPH) has been considered as a drug to treat SARS-CoV-2, the degradation of DPH from water was investigated and evaluated in this study by adopting an advanced oxidation/advanced reduction process – the UV/sulfite process. The UV/sulfite system was able to eliminate DPH within 6 mins under UV254nm and 1.0 mM sulfite. It was observed that the presence of NO3-, NO2-, Cl-, HCO3-, and SO42- anions in water can affect the performance of UV/Sulfite degradation system. The mechanism of UV/sulfite/anions was evaluated which the presence of NO3- in UV/sulfite process has revealed faster initial decay rate but lower final DPH removal. It was observed that the UV/Sulfite process was extremely sensitive to pH as the dissociation of ion species varied among pH. The reaction became sluggish in acidic solution due to the dissociation of less reactive species such as HSO3-. In alkaline solution, SO32- was the dominant species, producing powerful SO3∙- and eaq- when activated by UV at 254 nm. By conducting LC/MS analysis, the degradation pathway was proposed and can be summarized into four main pathways: hydroxylation, side chain cleavage, losing aromatic ring or ring opening. Scavenging tests were also carried out and validated the presence of various radicals contributing to the reaction, including eaq-, H˙, OH˙, SO3˙-, O2•- and SO4˙-.
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Affiliation(s)
- Hiu Lam So
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong
| | - Liwen Wang
- Department of Civil and Environmental Engineering, University of California, Berkeley, 760 Davis Hall, Berkeley, CA 94720, United States
| | - Jianghui Liu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong
| | - Wei Chu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Hong Kong
| | - Tao Li
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Amal Abdelhaleem
- Environmental Engineering Department, Egypt-Japan University of Science and Technology, New Borg El-Arab City, Alexandria 21934, Egypt
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15
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Saawarn B, Mahanty B, Hait S, Hussain S. Sources, occurrence, and treatment techniques of per- and polyfluoroalkyl substances in aqueous matrices: A comprehensive review. ENVIRONMENTAL RESEARCH 2022; 214:114004. [PMID: 35970375 DOI: 10.1016/j.envres.2022.114004] [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: 04/15/2022] [Revised: 07/04/2022] [Accepted: 07/25/2022] [Indexed: 06/15/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS), a class of synthetic organic pollutants, have prompted concerns about their global prevalence and possible health effects. This review consolidates the most recent data on different aspects of PFAS, such as their occurrence, and prominent sources. The current literature analysis of PFAS occurrence suggests significant variation in their concentration ranging from 0.025 to 1.2 × 108 ng/L in wastewater, 0.01 to 8.9 × 105 ng/L in surface water, and <0.01 to 1.3 × 104 ng/L in groundwater globally. Since conventional treatment techniques are inadequate in remediating PFAS, innovative treatment approaches based on their removal or mineralization mechanism have been comprehensively reviewed. Advanced treatment technologies have shown degradation or removal of PFAS to be around 6 and > 99.9% in different aqueous matrices. However, due to significant drawbacks in their applicability in wastewater treatment plants (WWTPs), a novel treatment train approach has emerged as an effective alternative. This approach synergistically integrates multiple remediation techniques while addressing the impediments of individual treatments. Furthermore, nanofiltration (NF270) combined with electrochemical degradation has been demonstrated to be the most efficient (>98%) treatment train approach in PFAS remediation. If implemented in WWTPs, nanofiltration followed by adsorption using activated carbon is also a viable method for PFAS removal.
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Affiliation(s)
- Bhavini Saawarn
- Department of Civil and Environmental Engineering, Indian Institute of Technology Patna, Bihar, 801 106, India
| | - Byomkesh Mahanty
- Department of Civil and Environmental Engineering, Indian Institute of Technology Patna, Bihar, 801 106, India
| | - Subrata Hait
- Department of Civil and Environmental Engineering, Indian Institute of Technology Patna, Bihar, 801 106, India.
| | - Sahid Hussain
- Department of Chemistry, Indian Institute of Technology Patna, Bihar, 801 106, India
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16
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Hoinkis N, Litter MI. Mechanisms of Sonochemical Transformation of Nitrate and Nitrite under Different Conditions: Influence of Additives and pH. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.2c02296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Nina Hoinkis
- Chemistry Department, Johannes Gutenberg-Universität Mainz, Duesbergweg 10-14, 55128Mainz, Germany
| | - Marta I. Litter
- Institute of Environmental Research and Engineering−Habitat and Sustainability School, National University of San Martín-CONICET, Campus Miguelete, Av. 25 de Mayo y Francia, 1650San Martín, Provincia de Buenos Aires, Argentina
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17
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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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18
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Bhat A, Pomerantz WCK, Arnold WA. Finding Fluorine: Photoproduct Formation during the Photolysis of Fluorinated Pesticides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:12336-12346. [PMID: 35972505 PMCID: PMC9454825 DOI: 10.1021/acs.est.2c04242] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/03/2022] [Accepted: 08/04/2022] [Indexed: 05/28/2023]
Abstract
The photolysis of pesticides with different fluorine motifs was evaluated to quantify the formation of fluorinated products in buffered aqueous systems, advanced oxidation (AOP) and reduction processes (ARP), and river water. Simulated sunlight quantum yields at pH 7 were 0.0033, 0.0025, 0.0015, and 0.00012 for penoxsulam, florasulam, sulfoxaflor, and fluroxypyr, respectively. The bimolecular rate constants with hydroxyl radicals were 2 to 5.7 × 1010 M-1 s-1 and, with sulfate radicals, 1.6 to 2.6 × 108 M-1 s-1 for penoxsulam, florasulam, and fluroxypyr, respectively. The rate constants of sulfoxaflor were 100-fold lower. Using quantitative 19F-NMR, complete fluorine mass balances were obtained. The maximum fluoride formation was 53.4 and 87.4% for penoxsulam and florasulam under ARP conditions, and 6.1 and 100% for sulfoxaflor and fluroxypyr under AOP conditions. Heteroaromatic CF3 and aliphatic CF2 groups were retained in multiple fluorinated photoproducts. Aryl F and heteroaromatic F groups were readily defluorinated to fluoride. CF3 and CF2 groups formed trifluoroacetate and difluoroacetate, and yields increased under oxidizing conditions. 19F-NMR chemical shifts and coupling analysis provided information on hydrogen loss on adjacent bonds or changes in chirality. Mass spectrometry results were consistent with the observed 19F-NMR products. These results will assist in selecting treatment processes for specific fluorine motifs and in the design of agrochemicals to reduce byproduct formation.
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Affiliation(s)
- Akash
P. Bhat
- Department
of Civil, Environmental, and Geo-, Engineering, University of Minnesota, 500 Pillsbury Dr. SE, Minneapolis, Minnesota 55455, United States
| | - William C. K. Pomerantz
- Department
of Chemistry, 207 Pleasant St. SE, University
of Minnesota, Minneapolis, Minnesota, 55455, United States
| | - William A. Arnold
- Department
of Civil, Environmental, and Geo-, Engineering, University of Minnesota, 500 Pillsbury Dr. SE, Minneapolis, Minnesota 55455, United States
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19
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Ambaye TG, Vaccari M, Prasad S, Rtimi S. Recent progress and challenges on the removal of per- and poly-fluoroalkyl substances (PFAS) from contaminated soil and water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:58405-58428. [PMID: 35754080 DOI: 10.1007/s11356-022-21513-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 06/12/2022] [Indexed: 06/15/2023]
Abstract
Currently, due to an increase in urbanization and industrialization around the world, a large volume of per- and poly-fluoroalkyl substances (PFAS) containing materials such as aqueous film-forming foam (AFFF), protective coatings, landfill leachates, and wastewater are produced. Most of the polluted wastewaters are left untreated and discharged into the environment, which causes high environmental risks, a threat to human beings, and hampered socioeconomic growth. Developing sustainable alternatives for removing PFAS from contaminated soil and water has attracted more attention from policymakers and scientists worldwide under various conditions. This paper reviews the recent emerging technologies for the degradation or sorption of PFAS to treat contaminated soil and water. It highlights the mechanisms involved in removing these persistent contaminants at a molecular level. Recent advances in developing nanostructured and advanced reduction remediation materials, challenges, and perspectives in the future are also discussed. Among the variety of nanomaterials, modified nano-sized iron oxides are the best sorbents materials due to their specific surface area and photogenerated holes and appear extremely promising in the remediation of PFAS from contaminated soil and water.
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Affiliation(s)
- Teklit Gebregiorgis Ambaye
- Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, Via Branze 43, 25123, Brescia, Italy
| | - Mentore Vaccari
- Department of Civil, Environmental, Architectural Engineering and Mathematics, University of Brescia, Via Branze 43, 25123, Brescia, Italy
| | - Shiv Prasad
- Division of Environment Science, ICAR-Indian Agricultural Research Institute New Delhi, New Delhi, 110012, India
| | - Sami Rtimi
- Global Institute for Water, Environment and Health, CH-1201, Geneva, Switzerland.
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20
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Pavanello A, Miranda MA, Marin ML. Organic photoredox catalysts for wastewater remediation: Beyond the established advanced oxidation processes. CHEMICAL ENGINEERING JOURNAL ADVANCES 2022. [DOI: 10.1016/j.ceja.2022.100296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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21
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Biswas S, Yamijala SSRKC, Wong BM. Degradation of Per- and Polyfluoroalkyl Substances with Hydrated Electrons: A New Mechanism from First-Principles Calculations. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8167-8175. [PMID: 35481774 PMCID: PMC10365488 DOI: 10.1021/acs.est.2c01469] [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] [Indexed: 06/14/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are synthetic contaminants found in drinking groundwater sources and a wide variety of consumer products. Because of their adverse environmental and human health effects, remediation of these persistent compounds has attracted significant recent attention. To gain mechanistic insight into their remediation, we present the first ab initio study of PFAS degradation via hydrated electrons─a configuration that has not been correctly considered in previous computational studies up to this point. To capture these complex dynamical effects, we harness ab initio molecular dynamics (AIMD) simulations to probe the reactivities of perfluorooctanoic (PFOA) and perfluorooctane sulfonic acid (PFOS) with hydrated electrons in explicit water. We complement our AIMD calculations with advanced metadynamics sampling techniques to compute free energy profiles and detailed statistical analyses of PFOA/PFOS dynamics. Although our calculations show that the activation barrier for C-F bond dissociation in PFOS is three times larger than that in PFOA, all the computed free energy barriers are still relatively low, resulting in a diffusion-limited process. We discuss our results in the context of recent studies on PFAS degradation with hydrated electrons to give insight into the most efficient remediation strategies for these contaminants. Most importantly, we show that the degradation of PFASs with hydrated electrons is markedly different from that with excess electrons/charges, a common (but largely incomplete) approach used in several earlier computational studies.
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Affiliation(s)
- Sohag Biswas
- Department of Chemical & Environmental Engineering, Materials Science & Engineering Program, Department of Physics & Astronomy, and Department of Chemistry, University of California-Riverside, Riverside, California 92521, United States
| | - Sharma S R K C Yamijala
- Department of Chemistry and Center for Atomistic Modelling and Materials Design, Indian Institute of Technology-Madras, Chennai 6000036, India
| | - Bryan M Wong
- Department of Chemical & Environmental Engineering, Materials Science & Engineering Program, Department of Physics & Astronomy, and Department of Chemistry, University of California-Riverside, Riverside, California 92521, United States
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22
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Fennell B, Mezyk SP, McKay G. Critical Review of UV-Advanced Reduction Processes for the Treatment of Chemical Contaminants in Water. ACS ENVIRONMENTAL AU 2022; 2:178-205. [PMID: 37102145 PMCID: PMC10114900 DOI: 10.1021/acsenvironau.1c00042] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
UV-advanced reduction processes (UV-ARP) are an advanced water treatment technology characterized by the reductive transformation of chemical contaminants. Contaminant abatement in UV-ARP is most often accomplished through reaction with hydrated electrons (eaq -) produced from UV photolysis of chemical sensitizers (e.g., sulfite). In this Review, we evaluate the photochemical kinetics, substrate scope, and optimization of UV-ARP. We find that quantities typically reported in photochemical studies of natural and engineered systems are under-reported in the UV-ARP literature, especially the formation rates, scavenging capacities, and concentrations of key reactive species like eaq -. The absence of these quantities has made it difficult to fully evaluate the impact of operating conditions and the role of water matrix components on the efficiencies of UV-ARP. The UV-ARP substrate scope is weighted heavily toward contaminant classes that are resistant to degradation by advanced oxidation processes, like oxyanions and per- and polyfluoroalkyl substances. Some studies have sought to optimize the UV-ARP treatment of these contaminants; however, a thorough evaluation of the impact of water matrix components like dissolved organic matter on these optimization strategies is needed. Overall, the data compilation, analysis, and research recommendations provided in this Review will assist the UV-ARP research community in future efforts toward optimizing UV-ARP systems, modeling the eaq --based chemical transformation kinetics, and developing new UV-ARP systems.
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Affiliation(s)
- Benjamin
D. Fennell
- Zachry
Department of Civil & Environmental Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - Stephen P. Mezyk
- Department
of Chemistry and Biochemistry, California
State University, Long Beach, Long Beach, California 90840, United States
| | - Garrett McKay
- Zachry
Department of Civil & Environmental Engineering, Texas A&M University, College Station, Texas 77843, United States
- . Phone: 979-458-6540
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23
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Bhat AP, Mundhenke TF, Whiting QT, Peterson AA, Pomerantz WC, Arnold WA. Tracking Fluorine during Aqueous Photolysis and Advanced UV Treatment of Fluorinated Phenols and Pharmaceuticals Using a Combined 19F-NMR, Chromatography, and Mass Spectrometry Approach. ACS ENVIRONMENTAL AU 2022; 2:242-252. [PMID: 37102144 PMCID: PMC10114624 DOI: 10.1021/acsenvironau.1c00057] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fluorine incorporation into organic molecules has increased due to desirable changes in the molecular physiochemical properties. Common fluorine motifs include: aliphatic fluorines and -CF3, or -F containing groups bonded directly onto an aromatic (Ar-CF3 and Ar-F) or heteroaromatic ring. Photolysis of these compounds, either in natural or engineered systems, is a potential source of new fluorinated byproducts. Given the potential persistence and toxicity of fluorinated byproducts, monitoring of product formation during photolysis of various fluorinated motifs is needed. 19F-NMR is a means to detect and quantify these species. Ar-CF3 and Ar-F model compounds (2-, 3-, and 4-(trifluoromethyl)phenol, 2-, 3-, 4-fluorophenol, and 2,6-, 3,5-difluorophenol) were photolyzed under a variety of aqueous conditions: pH 5, pH 7, pH 10, 1 mM H2O2 at pH 7 to form •OH, and 0.5 mM SO3 2- at pH 10 to form eaq -. Pharmaceuticals with the Ar-CF3 (fluoxetine) and Ar-F plus pyrazole-CF3 (sitagliptin) motifs were treated similarly. Parent molecule concentrations were monitored with high pressure liquid chromatography with a UV detector. Fluorine in the parent and product molecules was quantified with 19F-NMR and complete fluorine mass balances were obtained. High resolution mass spectrometry was used to further explore product identities. The major product for Ar-F compounds was fluoride. The Ar-CF3 model compounds led to fluoride and organofluorine products dependent on motif placement and reaction conditions. Trifluoroacetic acid was a product of 4-(trifluoromethyl)phenol and fluoxetine. Additional detected fluoxetine products identified using mass spectrometry resulted from addition of -OH to the aromatic ring, but a dealkylation product could not be distinguished from fluoxetine by 19F-NMR. Sitagliptin formed multiple products that all retained the pyrazole-CF3 motif while the Ar-F motif produced fluoride. 19F-NMR, mass spectrometry, and chromatography methods provide complementary information on the formation of fluorinated molecules by modification or fragmentation of the parent structure during photolysis, allowing screening for fluorinated photoproducts and development of fluorine mass balances.
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Affiliation(s)
- Akash P. Bhat
- Department of Civil, Environmental, and Geo- Engineering University of Minnesota, 500 Pillsbury Dr. SE, Minneapolis, Minnesota 55455, United States
| | - Thomas F. Mundhenke
- Department of Civil, Environmental, and Geo- Engineering University of Minnesota, 500 Pillsbury Dr. SE, Minneapolis, Minnesota 55455, United States
| | - Quinn T. Whiting
- Department of Civil, Environmental, and Geo- Engineering University of Minnesota, 500 Pillsbury Dr. SE, Minneapolis, Minnesota 55455, United States
| | - Alicia A. Peterson
- Department of Chemistry, College of Saint Benedict and Saint John’s University, 37 South College Avenue, St. Joseph, Minnesota 56374, United States
| | - William C.K. Pomerantz
- Department of Chemistry, University of Minnesota, 207 Pleasant St. SE, Minneapolis, Minnesota 55455, United States
| | - William A. Arnold
- Department of Civil, Environmental, and Geo- Engineering University of Minnesota, 500 Pillsbury Dr. SE, Minneapolis, Minnesota 55455, United States
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Pavanello A, Gomez-Mendoza M, de la Peña O'Shea VA, Miranda MA, Marin ML. Degradation of Benzotriazole UV-stabilizers in the presence of organic photosensitizers and visible light: A time-resolved mechanistic study. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2022; 230:112444. [PMID: 35429826 DOI: 10.1016/j.jphotobiol.2022.112444] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 03/16/2022] [Accepted: 04/05/2022] [Indexed: 12/28/2022]
Abstract
Benzotriazole UV-stabilizers (BUVSs) are commonly used in industry as solar filters, due to their strong UV light absorption. Because of their extended usage, environmental contamination of waters due to BUVSs constitutes a growing concern. Direct photodegradation of BUVSs is not efficient due to their intrinsic thermal pathways to release the absorbed light. Nevertheless, their abatement in natural environments could be assisted by chromophoric dissolved organic matter. Among the BUVSs, three representative candidates were selected, UV-326, UV-327 and UV-328, to demonstrate the potential of Riboflavin (RF) as a natural visible-light absorbing photocatalyst for the abatement of these recalcitrant pollutants under reductive conditions. The use of visible light and DABCO, as a model sacrificial electron donor, generates the radical anion RFTA.-. This key species reacts with the solar filters, achieving their reductive abatement from the medium. Moreover, the participation of every potential reactive species has been investigated by photophysical techniques, together with determination of the quenching rate constant for every reaction pathway. Consequently, evidence supported the main role of the reductive photodegradation pathway, being RFTA.- the key species in the abatement of BUVSs.
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Affiliation(s)
- Alice Pavanello
- Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022, Valencia, Spain
| | - Miguel Gomez-Mendoza
- Photoactivated Processes Unit, IMDEA Energy Institute, Technological Park of Móstoles, Avda. Ramón de la Sagra 3, 28935 Madrid, Spain
| | - Víctor A de la Peña O'Shea
- Photoactivated Processes Unit, IMDEA Energy Institute, Technological Park of Móstoles, Avda. Ramón de la Sagra 3, 28935 Madrid, Spain
| | - Miguel A Miranda
- Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022, Valencia, Spain
| | - M Luisa Marin
- Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avda. de los Naranjos s/n, E-46022, Valencia, Spain.
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Wacławek S, Ma X, Sharma VK, Xiao R, O'Shea KE, Dionysiou DD. Making waves: Defining advanced reduction technologies from the perspective of water treatment. WATER RESEARCH 2022; 212:118101. [PMID: 35092911 DOI: 10.1016/j.watres.2022.118101] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Revised: 12/21/2021] [Accepted: 01/16/2022] [Indexed: 06/14/2023]
Abstract
Studies related to advanced reduction technologies (ARTs) have grown exponentially since the term was first coined in 2013. Despite recent interests in ARTs, the conditions and requirements for these processes have yet to be defined and clarifed. In comparision to well defined advanced oxidation technologies/processes (AOTs/AOPs) which involve the generation of hydroxyl radical as the common characteristic, ARTs function by electron donation from a variety of reducing agents and activators. Based on an extensive literature review, we propose that ARTs be defined as processes employing strong chemical reductants with E° ≤ -2.3 V vs. normal hydrogen electrode at 25 ºC. While extensive studies have revealed critical fundamental details of AOTs/AOPs mediated processes, there are still significant gaps in elucidation of the mechanistic details of reductive degradation/transformation of highly toxic compounds by ARTs. A significant number of pollutants and toxins resistant to AOTs/AOPs treatment are effectively degraded by ARTs. A great leap is needed on understanding ARTs to fully utilize their potential to efficiently remediate recalcitrant compounds of different sources and structures.
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Affiliation(s)
- Stanisław Wacławek
- Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 1402/2, 461 17, Liberec 1, Czech Republic.
| | - Xingmao Ma
- Department of Civil and Environmental Engineering, Texas A&M University, College Station, TX 77843, USA.
| | - Virender K Sharma
- Department of Environmental and Occupational Health, School of Public Health, Program for the Environment and Sustainability, Texas A&M University, 212 Adriance Lab Rd., 1266 TAMU, College Station, TX 77843, USA.
| | - Ruiyang Xiao
- Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China.
| | - Kevin E O'Shea
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA.
| | - Dionysios D Dionysiou
- Department of Chemical and Environmental Engineering (ChEE), Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012, USA.
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Kazwini T, Yadav S, Ibrar I, Al-Juboori RA, Singh L, Ganbat N, Karbassiyazdi E, Samal AK, Subbiah S, Altaee A. Updated review on emerging technologies for PFAS contaminated water treatment. Chem Eng Res Des 2022. [DOI: 10.1016/j.cherd.2022.04.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Selective and Efficient Reduction of Nitrate to Gaseous Nitrogen from Drinking Water Source by UV/Oxalic Acid/Ferric Iron Systems: Effectiveness and Mechanisms. Catalysts 2022. [DOI: 10.3390/catal12030348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Nitrate (NO3−) reduction in water has been receiving increasing attention in water treatment due to its carcinogenic and endocrine-disrupting properties. This study employs a novel advanced reduction process, the UV/oxalic acid/ferric iron systems (UV/C2O42−/Fe3+ systems), in reducing NO3− due to its high reduction efficiency, excellent selectivity, and low treatment cost. The UV/C2O42−/Fe3+ process reduced NO3− with pseudo-first-order reaction rate constants of 0.0150 ± 0.0013 min−1, minimizing 91.4% of 60 mg/L NO3− and reaching 84.2% of selectivity for gaseous nitrogen after 180 min at pHini. 7.0 and 0.5 mg/L dissolved oxygen (DO). Carbon dioxide radical anion (CO2•−) played a predominant role in reducing NO3−. Gaseous nitrogen and NH4+, as well as CO2, were the main nitrogen- and carbon-containing products, respectively, and reduction pathways were proposed accordingly. A suitable level of oxalic acids (3 mM) and NO3− (60 mg/L) was recommended; increasing initial iron concentrations and UV intensity increased NO3− reduction. Instead, increasing the solution pH decreased the reduction, and 0.5–8.0 mg/L DO negligibly affected the process. Moreover, UV/C2O42−/Fe3+ systems were not retarded by 0.1–10 mM SO42− or Cl− or 0.1–1.0 mM HCO3− but were prohibited by 10 mM HCO3− and 30 mg-C/L humic acids. There was a lower reduction of NO3− in simulated groundwater (72.8%) than deionized water after 180 min at pHini. 7.0 and 0.5 mg/L DO, which meets the drinking water standard (<10 mg/L N-NO3−). Therefore, UV/C2O42−/Fe3+ systems are promising approaches to selectively and efficiently reduce NO3− in drinking water.
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Jafari B, Godini H, Soltani RDC, Seydi E. Effectiveness of UV/SO 32- advanced reduction process for degradation and mineralization of trichlorfon pesticide in water: identification of intermediates and toxicity assessment. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:20409-20420. [PMID: 34738214 DOI: 10.1007/s11356-021-17274-z] [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: 05/27/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
This study aimed to investigate the degradability, mineralization, proposed decomposition pathway, intermediate products, and toxicity of effluent from trichlorfon (TCF) degradation in water by UV/sulfite-advanced reduction process (UV/S-ARP). This study was experimentally performed in a photochemical reactor as a batch operation. The source of light was a UV lamp. Sulfite ion was used as the reducing agent. After the treatment, the residual concentration of TCF was measured by liquid chromatography equipped with tandem mass spectrometry (LC-MS/MS). UV/S-ARP had the highest performance at an initial pH of 7, a sulfite ion concentration of 120 mg/L, a contact time of 60 min, and a TCF concentration of 10 mg/L. Under such conditions, the degradation efficiency of TCF was 96.0%, and the amount of mineralization based on the removal of TOC and COD was 74.6% and 79.5%, respectively. The results of the degradation mechanism showed that eaq- and SO3•- have played the greatest role in dechlorination and transformation of TCF. Based on the identified intermediates, more complex compounds are transformed into compounds with simpler structures by UV/S-ARP. Evaluating the toxicity of TCF by-products via ECOSAR bioassay showed that as-generated intermediates do not have acute and chronic adverse effects on fish. The results of our study indicated that the advanced reduction process could be an effective process for the purification of TCF-contaminated water.
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Affiliation(s)
- Bahareh Jafari
- Department of Environmental Health Engineering, School of Health, Alborz University of Medical Sciences, Karaj, Iran
| | - Hatam Godini
- Department of Environmental Health Engineering, School of Health, Alborz University of Medical Sciences, Karaj, Iran.
- Research Center for Health, Safety and Environment (HSE), Alborz University of Medical Sciences, Karaj, Iran.
| | | | - Enayatollah Seydi
- Research Center for Health, Safety and Environment (HSE), Alborz University of Medical Sciences, Karaj, Iran
- Department of Occupational Health and Safety Engineering, School of Health, Alborz University of Medical Sciences, Karaj, Iran
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Xie Y, Hu S, Ma D, Liu R, Xu C, Liu H. NO 3- photolysis-induced advanced reduction process removes NO 3- and 2, 4, 6-tribromophenol. CHEMOSPHERE 2022; 288:132633. [PMID: 34687681 DOI: 10.1016/j.chemosphere.2021.132633] [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: 08/21/2021] [Revised: 10/06/2021] [Accepted: 10/19/2021] [Indexed: 06/13/2023]
Abstract
Reductive processes are an important type of pollutant removal technology, particularly for organic halogens. NO3- is an anion and pollutant that is commonly present in wastewater. In this study, a novel advanced reduction process (ARP) induced by NO3- photolysis was developed to remove 2,4,6-tribromophenol (TBP) and NO3-. The UV/NO3-/formate acid (FA) process achieved NO3- removal and improved the debromination of TBP (initial TBP concentration = 0.1 mM) (up to 97.8%), however, their coexistence adversely affected the reductive removal of each component. Acidic conditions (pH 3 in this study) benefited the removal of NO3- and the debromination of TBP. Cl- promoted NO3- removal in UV/NO3-/FA, however, it decreased the debromination effect of TBP by 27.8%. Humic acid, a typical dissolved organic matter, suppressed NO3- removal, TBP degradation and debromination under all experimental conditions. Methyl viologen significantly inhibited the performance of ARP, and this verified the role of CO2•- in this ARP. Insufficient reduction and over-reduction of NO3- were observed under different conditions and a greater amount of NH4+ was formed under the influence of TBP. The data also indicated that as much as 80% of the removed NO3- was converted to NO2-, and this is noteworthy. Due to the reductive radicals generated from the oxidation of FA, both oxidative and reductive products of TBP were detected in the effluent. The results of this study provide a potential technology for the reductive removal of organic halogens from NO3--rich wastewater.
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Affiliation(s)
- Yawei Xie
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China
| | - Shini Hu
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China
| | - Dehua Ma
- Key Laboratory of New Membrane Materials, Ministry of Industry and Information Technology, School of Environmental and Biological Engineering, Nanjing University of Science & Technology, Nanjing, 210094, China
| | - Rui Liu
- Zhejiang Provincial Key Laboratory of Water Science and Technology, Jiaxing, 314006, China
| | - Cancan Xu
- Zhejiang Provincial Key Laboratory of Water Science and Technology, Jiaxing, 314006, China
| | - Hongyuan Liu
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China.
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Degradation of Reactive Brilliant Red X-3B by Photo-Fenton-like Process: Effects of Water Chemistry Factors and Degradation Mechanism. WATER 2022. [DOI: 10.3390/w14030380] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Azo dye wastewater belongs to the highly concentrated organic wastewater, which is difficult to be treated by traditional biological processes. The oxidation efficiency of a single physicochemical method is not considerable. Recent research indicated that the advanced oxidation processes (AOPs) based on the highly reactive hydroxyl radical (∙OH) became one of the preferred methods in dealing with such dye wastewater. In this paper, the typical azo dye, reactive brilliant red X-3B, was employed as the target pollutant, and the transition metal Mn and hydrogen peroxide as the catalysts. A photo-Fenton-like process, UV/Mn2+-H2O2 system, was established, which enables a combination of various technologies to improve azo dye degradation efficiency while reducing disposal costs. The results indicated that the UV/Mn2+-H2O2 system had the synergism of Mn2+/H2O2 and UV/H2O2, which was 2.6 times greater than the sum of the two individual effects. And the degradation of X-3B reached the optimum under the conditions of 0.59 mmol/L of the Mn2+, 10 mmol/L of the H2O2, pH = 6 and a high level of DO. The ∙OH, generated from chem-catalytic and photocatalytic decomposition of H2O2, played the predominant role in the decolorization of X-3B and mineralization of its intermediates. The ∙OH tended to attack and break the chromophore group, resulting in the rapid decolorization of X-3B. The azo bond in X-3B was easy to be decomposed in the form of N2, while the triazinyl group was recalcitrant for ring opening. The degradation process of the UV/Mn2+-H2O2 system preferred to be conducted at an acidic condition and appropriate concentrations of Mn2+ and H2O2. The alkaline condition would decrease the utilization of H2O2, and excessive H2O2 would also quench the ∙OH.
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31
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Román Santiago A, Baldaguez Medina P, Su X. Electrochemical remediation of perfluoroalkyl substances from water. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2021.139635] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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32
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Deng Y, Liang Z, Lu X, Chen D, Li Z, Wang F. The degradation mechanisms of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) by different chemical methods: A critical review. CHEMOSPHERE 2021; 283:131168. [PMID: 34182635 DOI: 10.1016/j.chemosphere.2021.131168] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 06/04/2021] [Accepted: 06/08/2021] [Indexed: 06/13/2023]
Abstract
Per- and polyfluoroalkyl substances (PFASs) are a class of artificial compounds comprised of a perfluoroalkyl main chain and a terminal functional group. With them being applied in a wide range of applications, PFASs have drawn increasing regulatory attention and research interests on their reductions and treatments due to their harmful effects on environment and human beings. Among numerous studies, chemical treatments (e.g., photochemical, electrochemical, and thermal technologies) have been proved to be important methods to degradation PFASs. However, the pathways and mechanisms for the degradation of PFASs through these chemical methods still have not been well documented. This article therefore provides a comprehensive review on the degradation mechanisms of two important PFASs (perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS)) with photochemical, electrochemical and thermal methods. Different decomposition mechanisms of PFOA and PFOS are reviewed and discussed. Overall, the degradation pathways of PFASs are associated closely with their head groups and chain lengths, and H/F exchange and chain shortening were found to be predominant degradation mechanisms. The clear study on the degradation mechanisms of PFOA and PFOS should be very useful for the complete degradation or mineralization of PFASs in the future.
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Affiliation(s)
- Yun Deng
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, China
| | - Zhihong Liang
- The Pearl River Water Resources Research Institute, Guangzhou, Guangdong, 510611, China
| | - Xingwen Lu
- School of Environmental Science and Engineering and Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou, 510006, China
| | - Da Chen
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, China
| | - Zhe Li
- School of Engineering and Materials Science, Faculty of Science and Engineering, Queen Mary University of London, Mile End Road, London, E1 4NS, UK
| | - Fei Wang
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, China.
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Barhoum A, Favre T, Sayegh S, Tanos F, Coy E, Iatsunskyi I, Razzouk A, Cretin M, Bechelany M. 3D Self-Supported Nitrogen-Doped Carbon Nanofiber Electrodes Incorporated Co/CoO x Nanoparticles: Application to Dyes Degradation by Electro-Fenton-Based Process. NANOMATERIALS 2021; 11:nano11102686. [PMID: 34685127 PMCID: PMC8540561 DOI: 10.3390/nano11102686] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/01/2021] [Accepted: 10/05/2021] [Indexed: 11/16/2022]
Abstract
We developed free-standing nitrogen-doped carbon nanofiber (CNF) electrodes incorporating Co/CoOx nanoparticles (NPs) as a new cathode material for removing Acid Orange 7 (AO7; a dye for wool) from wastewater by the heterogeneous electro-Fenton reaction. We produced the free-standing N-doped CNF electrodes by electrospinning a polyacrylonitrile (PAN) and cobalt acetate solution followed by thermal carbonation of the cobalt acetate/PAN nanofibers under a nitrogen atmosphere. We then investigated electro-Fenton-based removal of AO7 from wastewater with the free-standing N-doped-CNFs-Co/CoOx electrodes, in the presence or not of Fe2+ ions as a co-catalyst. The electrochemical analysis showed the high stability of the prepared N-doped-CNF-Co/CoOx electrodes in electrochemical oxidation experiments with excellent degradation of AO7 (20 mM) at acidic to near neutral pH values (3 and 6). Electro-Fenton oxidation at 10 mA/cm2 direct current for 40 min using the N-doped-CNF-Co/CoOx electrodes loaded with 25 wt% of Co/CoOx NPs led to complete AO7 solution decolorization with total organic carbon (TOC) removal values of 92.4% at pH 3 and 93.3% at pH 6. The newly developed N-doped-CNF-Co/CoOx electrodes are an effective alternative technique for wastewater pre-treatment before the biological treatment.
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Affiliation(s)
- Ahmed Barhoum
- NanoStruc Research Group, Chemistry Department, Faculty of Science, Helwan University, Cairo 11795, Egypt
- Institut Européen des Membranes (IEM), UMR 5635, Université Montpellier, École Nationale Supérieure de Chimie de Montpellier (ENSCM), Centre National de la Recherche Scientifique (CNRS), Place Eugène Bataillon, 34095 Montpellier, France; (T.F.); (S.S.); (F.T.); (M.C.)
- School of Chemical Sciences, Fraunhofer Project Centre, Dublin City University, D09 V209 Dublin, Ireland
- Correspondence: (A.B.); (M.B.)
| | - Therese Favre
- Institut Européen des Membranes (IEM), UMR 5635, Université Montpellier, École Nationale Supérieure de Chimie de Montpellier (ENSCM), Centre National de la Recherche Scientifique (CNRS), Place Eugène Bataillon, 34095 Montpellier, France; (T.F.); (S.S.); (F.T.); (M.C.)
| | - Syreina Sayegh
- Institut Européen des Membranes (IEM), UMR 5635, Université Montpellier, École Nationale Supérieure de Chimie de Montpellier (ENSCM), Centre National de la Recherche Scientifique (CNRS), Place Eugène Bataillon, 34095 Montpellier, France; (T.F.); (S.S.); (F.T.); (M.C.)
- Laboratoire d’Analyses Chimiques, Faculty of Sciences, LAC—Lebanese University, Jdeidet 90656, Lebanon;
| | - Fida Tanos
- Institut Européen des Membranes (IEM), UMR 5635, Université Montpellier, École Nationale Supérieure de Chimie de Montpellier (ENSCM), Centre National de la Recherche Scientifique (CNRS), Place Eugène Bataillon, 34095 Montpellier, France; (T.F.); (S.S.); (F.T.); (M.C.)
- Laboratoire d’Analyses Chimiques, Faculty of Sciences, LAC—Lebanese University, Jdeidet 90656, Lebanon;
| | - Emerson Coy
- NanoBioMedical Centre, Adam Mickiewicz University, 3, Wszechnicy Piastowskiej Str., 61-614 Poznan, Poland; (E.C.); (I.I.)
| | - Igor Iatsunskyi
- NanoBioMedical Centre, Adam Mickiewicz University, 3, Wszechnicy Piastowskiej Str., 61-614 Poznan, Poland; (E.C.); (I.I.)
| | - Antonio Razzouk
- Laboratoire d’Analyses Chimiques, Faculty of Sciences, LAC—Lebanese University, Jdeidet 90656, Lebanon;
| | - Marc Cretin
- Institut Européen des Membranes (IEM), UMR 5635, Université Montpellier, École Nationale Supérieure de Chimie de Montpellier (ENSCM), Centre National de la Recherche Scientifique (CNRS), Place Eugène Bataillon, 34095 Montpellier, France; (T.F.); (S.S.); (F.T.); (M.C.)
| | - Mikhael Bechelany
- Institut Européen des Membranes (IEM), UMR 5635, Université Montpellier, École Nationale Supérieure de Chimie de Montpellier (ENSCM), Centre National de la Recherche Scientifique (CNRS), Place Eugène Bataillon, 34095 Montpellier, France; (T.F.); (S.S.); (F.T.); (M.C.)
- Correspondence: (A.B.); (M.B.)
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Xiao Q, Yu S. Reduction of bromate from drinking water by sulfite/ferric ion systems: Efficacy and mechanisms. JOURNAL OF HAZARDOUS MATERIALS 2021; 418:125940. [PMID: 34111754 DOI: 10.1016/j.jhazmat.2021.125940] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 04/04/2021] [Accepted: 04/19/2021] [Indexed: 06/12/2023]
Abstract
In this work, we investigate radical-based chemical reduction systems for BrO3- reduction. Sulfite/ferric ions [S(IV)/Fe(III)] systems eliminated 85% of 0.1 mM BrO3- in 1 min at pHini. 7.0, and 2.2 mg/L dissolved oxygen (DO) with rate constants (2.104 ± 0.090 min-1) orders of magnitude faster than previously published advanced reduction processes. Increasing S(IV) and Fe(III) concentrations and decreasing DO and pH contributed to faster BrO3- reduction likely due to enhanced reactive species. Lower anionic levels (0.5 mM) did not hinder BrO3- reduction but further increases in the levels to 1.0 mM decreased their reduction. Notably, S(IV)/Fe(III) process reduced 68% of 25.6 μg/L BrO3- in 3 min from tap water at pHini. 7.0, 0.02 mM Fe(III), and 1.0 mM S(IV), meeting drinking water standard (<10 μg/L). Also, ~99% of irons could be removed after the following activated carbon treatment. Moreover, sulfite radicals formed by S(IV) activation with Fe(III) were significant reactive species in the S(IV)/Fe(III) system. Reduction pathways were proposed accordingly. Collectively, S(IV)/Fe(III) process is a viable technology for reductively decontaminating realistic waters, especially when applied between the ozone-activated carbon process (i.e., the ozone-S(IV)/Fe(III)-activated carbon process).
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Affiliation(s)
- Qian Xiao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Shuili Yu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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35
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Chen B, Jiang J, Yang X, Zhang X, Westerhoff P. Roles and Knowledge Gaps of Point-of-Use Technologies for Mitigating Health Risks from Disinfection Byproducts in Tap Water: A Critical Review. WATER RESEARCH 2021; 200:117265. [PMID: 34091221 PMCID: PMC8634687 DOI: 10.1016/j.watres.2021.117265] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/11/2021] [Accepted: 05/14/2021] [Indexed: 05/19/2023]
Abstract
Due to rising concerns about water pollution and affordability, there is a rapidly-growing public acceptance and global market for a variety of point-of-use (POU) devices for domestic uses. However, the efficiencies and mechanisms of POU technologies for removing regulated and emerging disinfection byproducts (DBPs) are still not systematically known. To facilitate the development of this field, we summarized performance trends of four common technologies (i.e., boiling, adsorption, membrane filtration, and advanced oxidation) on mitigating preformed DBPs and identified knowledge gaps. The following highest priority knowledge gaps include: 1) data on DBP levels at the tap or cup in domestic applications; 2) certainty regarding the controls of DBPs by heating processes as DBPs may form and transform simultaneously; 3) standards to evaluate the performance of carbon-based materials on varying types of DBPs; 4) long-term information on the membrane performance in removing DBPs; 5) knowledge of DBPs' susceptibility toward advanced redox processes; 6) tools to monitor/predict the toxicity and diversity of DBPs formed in waters with varying precursors and when implementing different treatment technologies; and 7) social acceptance and regulatory frameworks of incorporating POU as a potential supplement to current centralized-treatment focused DBP control strategies. We conclude by identifying research needs necessary to assure POU systems protect the public against regulated and emerging DBPs.
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Affiliation(s)
- Baiyang Chen
- State Key Laboratory of Urban Water Resource and Environment, Shenzhen Key Laboratory of Organic Pollution Prevention and Control, Harbin Institute of Technology (Shenzhen), 518055, China.
| | - Jingyi Jiang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xin Yang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China.
| | - Xiangru Zhang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
| | - Paul Westerhoff
- NSF Nanosystems Engineering Research Center for Nanotechnology-Enabled Water Treatment, School of Sustainable Engineering and the Built Environment, Ira A. Fulton Schools of Engineering, Arizona State University, Tempe, AZ 85287-3005, United States.
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Cao Y, Qiu W, Li J, Jiang J, Pang S. Review on UV/sulfite process for water and wastewater treatments in the presence or absence of O 2. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 765:142762. [PMID: 33071111 DOI: 10.1016/j.scitotenv.2020.142762] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/14/2020] [Accepted: 09/28/2020] [Indexed: 06/11/2023]
Abstract
Based on previous reports, UV/sulfite process is generally used as an advanced reduction process (ARP) since eaq- and/or ∙H, both with strong reduction potential, could be substantially generated herein. Very recently, the combination of UV and sulfite as an advanced oxidation process (AOP) or an oxidation-reduction coupling process has attracted increasing interest due to the yield of SO4∙- and/or HO∙. Herein, the application of UV/sulfite as an ARP and AOP (or oxidation-reduction coupling process) during water and wastewater treatments is reviewed respectively. (1) In the absence of O2, UV/sulfite works as an ARP. The generation mechanism of reactive reduction species and various contaminants removal (including degradation kinetics and efficiency, decomposition mechanisms, effects of some factors, etc.) is summarized in detail and systematically. Moreover, both the application of different types of UV lights and the economic evaluation are summarized systematically. (2) In the presence of O2, UV/sulfite could be used as an AOP or oxidation-reduction coupling process. The generation mechanism of reactive oxidation species and influencing factors is also presented in detail. Moreover, two ways (including homogeneous and heterogeneous activation) used to enhance the UV/sulfite oxidation potential are summarized respectively. Moreover, several knowledge gaps and research needs for further research are proposed. Overall, this review provides an overview for in-depth understanding of UV/sulfite as an ARP or AOP (oxidation-reduction coupling process) during water and wastewater treatments.
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Affiliation(s)
- Ying Cao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wei Qiu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Juan Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jin Jiang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China.
| | - Suyan Pang
- Key Laboratory of Songliao Aquatic Environment, Ministry of Education, School of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun 130118, China
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Yu X, Zhang J, Zheng Y. Perchlorate adsorption onto epichlorohydrin crosslinked chitosan hydrogel beads. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:143236. [PMID: 33187716 DOI: 10.1016/j.scitotenv.2020.143236] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 10/22/2020] [Accepted: 10/22/2020] [Indexed: 06/11/2023]
Abstract
Perchlorate (ClO4-) in water is an emerging contaminant that threatens human health by inhibiting the uptake of iodine in the thyroid gland. Biopolymer adsorbents including chitosan hydrogel beads (CSBs) have attracted increasing attentions in water treatment for their low costs, ease in preparation, and environmental friendliness. However, the adsorption capacity for ClO4- by several crosslinked CSBs has been shown to be low. To overcome this, epichlorohydrin (ECH) crosslinked CSBs (ECH-CSBs) that preserved -NH2 functional groups as potential sites for adsorption are synthesized and characterized, followed by batch adsorption experiments to evaluate adsorption and desorption reactions. The point of zero charge is determined to be 5.1 ± 0.1. Both XPS spectra and DFT calculations support that electrostatic interaction between ClO4- and protonated -NH3+ functional groups is responsible for adsorption that reaches a capacity of 63.4 to 76.3 mg/g between pH of 4.0-10.0 at 303.15 K that follows Langmuir isotherm. ECH crosslinking also enhances hydrophilicity of CSBs to allow for increased adsorption for ClO4-. Adsorption of ClO4- (10 and 100 mg/L) follows a pseudo-first order kinetics with equilibrium time of 2-6 h but is limited by intra-particle diffusion. Anions common in natural waters exhibit interference effects due to similar electrostatic attraction mechanism, thus HCO3- and SO42- with high abundance in natural waters need pre-treatment. Regeneration of the adsorbents to 100% of its adsorption capacity by rinsing with 0.1 M NaOH is demonstrated for 12 cycles due to complete desorption of ClO4- via electrostatic repulsion, assuring reusability.
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Affiliation(s)
- Xiaolong Yu
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; College of Environmental Sciences and Engineering, Nankai University, Tianjin 300350, China
| | - Juan Zhang
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yan Zheng
- State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
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Yazdanbakhsh A, Eslami A, Mahdipour F, Ghanbari F, Ghasemi SM, Atamaleki A, Maleksari HS, Lin KYA. Dye degradation in aqueous solution by dithionite/UV-C advanced reduction process (ARP): Kinetic study, dechlorination, degradation pathway and mechanism. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2020.112995] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Acevedo-Barrios R, Olivero-Verbel J. Perchlorate Contamination: Sources, Effects, and Technologies for Remediation. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2021; 256:103-120. [PMID: 34611758 DOI: 10.1007/398_2021_66] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Perchlorate is a persistent pollutant, generated via natural and anthropogenic processes, that possesses a high potential for endocrine disruption in humans and biota. It inhibits iodine fixation, a major reason for eliminating this pollutant from ecosystems. Remediation of perchlorate can be achieved with various physicochemical treatments, especially at low concentrations. However, microbiological approaches using microorganisms, such as those from the genera Dechloromonas, Serratia, Propionivibrio, Wolinella, and Azospirillum, are promising when perchlorate pollution is extensive. Perchlorate-reducing bacteria, isolated from harsh environments, for example saline soils, mine sediments, thermal waters, wastewater treatment plants, underground gas storage facilities, and remote areas, including the Antarctica, can provide removal yields from 20 to 100%. Perchlorate reduction, carried out by a series of enzymes, such as perchlorate reductase and superoxide chlorite, depends on pH, temperature, salt concentration, metabolic inhibitors, nutritional conditions, time of contact, and cellular concentration. Microbial degradation is cost-effective, simple to implement, and environmentally friendly, rendering it a viable method for alleviating perchlorate pollution in the environment.
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Affiliation(s)
- Rosa Acevedo-Barrios
- Environmental and Computational Chemistry Group, School of Pharmaceutical Sciences, University of Cartagena, Cartagena, Colombia
- Grupo de Investigación en Estudios Químicos y Biológicos, Facultad de Ciencias Básicas, Universidad Tecnológica de Bolívar, Cartagena, Colombia
| | - Jesus Olivero-Verbel
- Environmental and Computational Chemistry Group, School of Pharmaceutical Sciences, University of Cartagena, Cartagena, Colombia.
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Olatunde OC, Kuvarega AT, Onwudiwe DC. Photo enhanced degradation of polyfluoroalkyl and perfluoroalkyl substances. Heliyon 2020; 6:e05614. [PMID: 33305052 PMCID: PMC7718166 DOI: 10.1016/j.heliyon.2020.e05614] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 09/26/2020] [Accepted: 11/24/2020] [Indexed: 11/16/2022] Open
Abstract
The increase in the presence of highly recalcitrant poly- and per- fluoroalkyl substances (PFAS) in the environment, plant tissues and animals continues to pose serious health concerns. Several treatment methods such as physical, biological and chemical processes have been explored to deal with these compounds. Current trends have shown that the destructive treatment processes, which offer degradation and mineralization of PFASs, are the most desirable process among researchers and policy makers. This article, therefore, reviews the degradation and defluorination processes, their efficiencies and the degradation mechanism of photon-based processes. It shows that high degradation and defluorination efficiency of PFASs could be achieved by photon driven processes such as photolysis, photochemical, photocatalysis and photoreduction. The efficiency of these processes is greatly influenced by the nature of light and the reactive radical generated in the system. The limitation of these processes, however, include the long reaction time required and the use of anoxic reaction conditions, which are not obtainable at ambient conditions.
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Affiliation(s)
- Olalekan C. Olatunde
- Material Science Innovation and Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa
- Department of Chemistry, School of Physical and Chemical Sciences, Faculty of Natural and Agricultural Sciences, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa
| | - Alex T. Kuvarega
- Nanotechnology and Water Sustainability Research Unit, College of Science, Engineering and Technology, University of South Africa, Florida 1709, South Africa
| | - Damian C. Onwudiwe
- Material Science Innovation and Modelling (MaSIM) Research Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa
- Department of Chemistry, School of Physical and Chemical Sciences, Faculty of Natural and Agricultural Sciences, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho 2735, South Africa
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Singh RK, Multari N, Nau-Hix C, Woodard S, Nickelsen M, Mededovic Thagard S, Holsen TM. Removal of Poly- and Per-Fluorinated Compounds from Ion Exchange Regenerant Still Bottom Samples in a Plasma Reactor. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:13973-13980. [PMID: 33103418 DOI: 10.1021/acs.est.0c02158] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
"High-concentration" and "low-concentration" bench-scale batch plasma reactors were used to effectively degrade per- and polyfluoroalkyl substances (PFAS) at a high concentration (∼100 mg/L) and a low concentration (<1 μg/L), respectively, in ion exchange (IX) regenerant still bottom (SB) solutions. In the SBs, numerous PFAS were detected with a wide concentration range (∼0.01 to 100 mg/L; total oxidizable precursors (TOP) ∼4000 to 10000 mg/L). In the "high-concentration" plasma reactor, the concentrations of PFAS precursors and long-chain perfluoroalkyl acids (PFAAs) (≥6C for PFSAs and ≥8C for perfluorocarboxylic acids (PFCAs)) were decreased by >99.9% in 2 h, and short-chain PFAAs (<6C for perfluorocarboxylic acids (PFSAs) and <8C PFCAs) were decreased by >99% in 6 h of treatment. Subsequently, a "low concentration" plasma reactor was used to remove additional PFAAs. In this reactor, the addition of CTAB (cetrimonium bromide, a cationic surfactant) caused short-chain PFAAs, other than PFBA, to be removed to below detection limits in 90 min of treatment time. Overall, >99% of the TOP present in SBs was removed during the treatment. Fluorine recovery of 47 to 117% was obtained in six SB samples. Energy requirement (EE/O) for the treatment of PFOA and PFOS from SBs ranged from 380 to 830 kWh/m3.
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Affiliation(s)
- Raj Kamal Singh
- Plasma Research Laboratory, Department of Chemical and Biomolecular Engineering, Clarkson University, Potsdam, New York 13699, United States
| | - Nicholas Multari
- Plasma Research Laboratory, Department of Chemical and Biomolecular Engineering, Clarkson University, Potsdam, New York 13699, United States
| | - Chase Nau-Hix
- Plasma Research Laboratory, Department of Chemical and Biomolecular Engineering, Clarkson University, Potsdam, New York 13699, United States
| | - Steven Woodard
- Emerging Compounds Treatment Technologies (ECT2) Inc., Portland, Maine 04103, United States
| | - Michael Nickelsen
- Emerging Compounds Treatment Technologies (ECT2) Inc., Portland, Maine 04103, United States
| | - Selma Mededovic Thagard
- Plasma Research Laboratory, Department of Chemical and Biomolecular Engineering, Clarkson University, Potsdam, New York 13699, United States
| | - Thomas M Holsen
- Department of Civil and Environmental Engineering, Clarkson University, Potsdam, New York 13699, United States
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Asgari G, Seidmohammadi A, Rahmani AR, Samarghandi MR, Faraji H. Application of the UV/sulfoxylate/phenol process in the simultaneous removal of nitrate and pentachlorophenol from the aqueous solution. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113581] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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43
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Critical Perspective on Advanced Treatment Processes for Water and Wastewater: AOPs, ARPs, and AORPs. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10134549] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Emerging contaminants’ presence in water, wastewater, and aquatic environments has been widely reported. Their environmental and health-related effects, and the increasing tendency towards wastewater reuse require technology that could remove to a greater degree, or even mineralize, all these contaminants. Currently, the most commonly used process technologies for their removal are advanced oxidation processes (AOPs); however, recent advances have highlighted other advanced treatment processes (ATPs) as possible alternatives, such as advanced reduction processes (ARPs) and advanced oxidation-reduction processes (AORPs). Although they are not yet widely diffused, they may remove contaminants that are not readily treatable by AOPs, or offer better performance than the former. This paper presents an overview of some of the most common or promising ATPs for the removal of contaminants from water and wastewater, and their application, with discussion of their limitations and merits. Issues about technologies’ costs and future perspectives in the water sector are discussed.
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Cui J, Gao P, Deng Y. Destruction of Per- and Polyfluoroalkyl Substances (PFAS) with Advanced Reduction Processes (ARPs): A Critical Review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:3752-3766. [PMID: 32162904 DOI: 10.1021/acs.est.9b05565] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Advanced reduction processes (ARPs) have emerged as a promising method for destruction of persistent per- and polyfluoroalkyl substances (PFAS) in water due to the generation of short-lived and highly reductive hydrated electrons (eaq-). This study provides a critical review on the mechanisms and performance of reductive destruction of PFAS with eaq-. Unique properties of eaq- and its generation in different ARP systems, particularly UV/sulfite and UV/iodide, are overviewed. Different degradation mechanisms of PFAS chemicals, such as perfluorooctanoic acid (PFOA), perfluorooctanesulfonate (PFOS), and others (e.g., short chain perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs), per- and polyfluoro dicarboxylic acids, and fluorotelomer carboxylic acids), are reviewed, discussed, and compared. The degradation pathways of these PFAS chemicals rely heavily upon their head groups. For specific PFAS types, fluoroalkyl chain lengths may also affect their reductive degradation patterns. Degradation and defluorination efficiencies of PFAS are considerably influenced by solution chemistry parameters and operating factors, such as pH, dose of chemical solute (i.e., sulfite or iodide) for eaq- photoproduction, dissolved oxygen, humic acid, nitrate, and temperature. Furthermore, implications of the state-of-the-art knowledge on practical PFAS control actions in water industries are discussed and the priority research needs are identified.
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Affiliation(s)
- Junkui Cui
- Department of Earth and Environmental Studies, Montclair State University, Montclair, New Jersey 07043, United States
| | - Panpan Gao
- Department of Earth and Environmental Studies, Montclair State University, Montclair, New Jersey 07043, United States
- School of Environmental Studies, China University of Geosciences, Wuhan, Hubei Province 430074, P. R. China
| | - Yang Deng
- Department of Earth and Environmental Studies, Montclair State University, Montclair, New Jersey 07043, United States
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Lu D, Sha S, Luo J, Huang Z, Zhang Jackie X. Treatment train approaches for the remediation of per- and polyfluoroalkyl substances (PFAS): A critical review. JOURNAL OF HAZARDOUS MATERIALS 2020; 386:121963. [PMID: 31896004 DOI: 10.1016/j.jhazmat.2019.121963] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 12/16/2019] [Accepted: 12/22/2019] [Indexed: 05/27/2023]
Abstract
Per- and polyfluoroalkyl substances (PFAS) have recently drawn great attention due to their ubiquitous presence in aquatic environments and potential toxicity to human health and the environment. A number of recent studies have demonstrated that "passive" removal approaches, such as adsorption, filtration, and reverse osmosis or "active" degradation technologies, such as enhanced photolysis, electrochemical oxidation, and sonochemical destruction, are all able to individually conduct remedial measures for PFAS contamination at some level. However, drawbacks, specifically high energy consumption, low cost-efficiency, and extreme operating conditions, are commonly observed from these studies which significantly suppress the future for commercialization of these innovative technologies. Since 2015, a new trend of PFAS remediation has emerged that uses multiple synergetic technologies simultaneously (known as treatment train processes) to effectively achieve in-situ remediation of PFAS. This paper provides new insight of the recently reported treatment train studies selected from approximately 150 different publications with regards to the remediation of PFAS and discusses their innovative designs, remediation performances, present limits, and possible improvements. Based on a comprehensive review of the current treatment train studies, this review work proposes a new design that consists of three individual technologies, namely, nanofiltration, electrochemical anodic oxidation, and electro-Fenton degradation, to maximize economic and environmental benefits of PFAS remedial measures.
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Affiliation(s)
- Dingnan Lu
- Department of Civil and Environmental Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, United States.
| | - Sha Sha
- Department of Civil and Environmental Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, United States.
| | - Jiayue Luo
- Department of Civil and Environmental Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, United States.
| | - Zhuangrong Huang
- Department of Civil and Environmental Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, United States.
| | - Xiaoqi Zhang Jackie
- Department of Civil and Environmental Engineering, University of Massachusetts Lowell, One University Ave., Lowell, MA 01854, United States.
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46
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Fulong CRP, Guardian MGE, Aga DS, Cook TR. A Self-Assembled Iron(II) Metallacage as a Trap for Per- and Polyfluoroalkyl Substances in Water. Inorg Chem 2020; 59:6697-6708. [DOI: 10.1021/acs.inorgchem.9b03405] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Cressa Ria P. Fulong
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Mary Grace E. Guardian
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Diana S. Aga
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Timothy R. Cook
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
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47
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Dereven’kov IA, Makarov SV. Catalytic effect of tetrasulfonated cobalt phthalocyanine on selenite reduction by dithionite. REACTION KINETICS MECHANISMS AND CATALYSIS 2019. [DOI: 10.1007/s11144-019-01687-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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48
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Long L, Bu Y, Chen B, Sadiq R. Removal of urea from swimming pool water by UV/VUV: The roles of additives, mechanisms, influencing factors, and reaction products. WATER RESEARCH 2019; 161:89-97. [PMID: 31181450 DOI: 10.1016/j.watres.2019.05.098] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 05/05/2019] [Accepted: 05/29/2019] [Indexed: 06/09/2023]
Abstract
To discover an applicable technology for urea abatement from swimming pool water (SPW), this study compared the performances of seven ultraviolet (UV)-based technologies on urea removal, including UV alone, UV coupled with hydrogen peroxide (UV/H2O2), sulfite (UV/Na2SO3), potassium persulfate (UV/K2S2O8), a combination of UV and vacuum UV (UV/VUV), and UV/VUV in tandem with either H2O2 (VUV/H2O2) or potassium persulfate (VUV/K2S2O8). Among them, UV and UV/Na2SO3 showed little removal ability, and UV/H2O2 removed only 12.8% of urea within 3-h experiments, while UV/VUV degraded 71.7% of urea without introducing substantial total dissolved solids (TDS). Therefore, UV/VUV was considered as a promising technology for further exploration. In comparison, although UV/K2S2O8 exhibited higher urea removal than UV/VUV, it caused dramatic increases of TDS, which made the regulatory threshold for the TDS increment difficult to maintain. Within UV/VUV studies, some common components in SPW (e.g., cyanuric acid, humic acid, nitrate, and bicarbonate) inhibited the removal process, whereas chloride and sulfate facilitated it, while free chlorine at doses ≤ 3 mg-Cl2/L and pH levels from 6.8 to 8.0 imposed little impact on urea degradation. Overall, UV/VUV degraded 40.0% and 22.2% of urea from tap water and SPW, respectively; both were lower than the efficiency observed in ultrapure water. As for reaction byproducts, urea phototransformation via UV/VUV yielded nitrate and ammonia as the key products with the mass balance of nitrogen element being met. However, the contents of organic carbon decreased at a rate slightly lower than urea degradation, suggesting that urea was mostly mineralized and slightly converted to unknown organic compounds. The results hence demonstrate that UV/VUV is an effective alternative for urea removal from SPW.
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Affiliation(s)
- Liangchen Long
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control of Harbin Institute of Technology, Shenzhen, 518055, China
| | - Yinan Bu
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control of Harbin Institute of Technology, Shenzhen, 518055, China
| | - Baiyang Chen
- Shenzhen Key Laboratory of Organic Pollution Prevention and Control of Harbin Institute of Technology, Shenzhen, 518055, China.
| | - Rehan Sadiq
- School of Engineering, University of British Columbia Okanagan Campus, Kelowna, BC, V1V1V7, Canada
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49
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Liu XC, Li WQ, Wang YR, Zhou GN, Wang YX, He CS, Wang GM, Mu Y. Cathode-Introduced Atomic H* for Fe(II)-Complex Regeneration to Effective Electro-Fenton Process at a Natural pH. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:6927-6936. [PMID: 31117534 DOI: 10.1021/acs.est.9b00345] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Promotion of iron solubility using ligands is the preliminary step in the homogeneous electro-Fenton (EF) process at a mild pH, but the chelate efficiencies of most organic ligands are unsatisfactory, resulting in insufficient Fe(II) availability. In this study, atomic H* was, for the first time, introduced to the EF process to accelerate the regeneration of the Fe(II)-complex at a mild pH using a Ni-deposited carbon felt (Ni-CF) cathode. The introduction of atomic H* significantly elevated total organic carbon (TOC) abatement of ciprofloxacin (CIP) from 42% (CF) to 81% (Ni-CF) at a natural pH. In the presence of humic acids (HAs), atomic H* introduced via Ni-CF enhanced the CIP degradation rate to 10 times that of the CF at a mild pH. The electron spin resonance (ESR), density functional theory (DFT) calculations, electrochemical characterization, and in situ electrochemical Raman study clearly demonstrated that the atomic H* generated from the Ni-CF cathode was highly efficient at reducing Fe(III)-complexes at a natural pH. Additionally, the Ni-CF could generate atomic H* without significant nickel leaching. Thus, the atomic H* could continuously facilitate iron cycling and, consequently, enhance pollutant mineralization via the homogeneous EF process at a mild pH in an environmentally friendly manner.
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Affiliation(s)
- Xiao-Cheng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
| | - Wen-Qiang Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
| | - Yi-Ran Wang
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
| | - Guan-Nan Zhou
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
| | - Yi-Xuan Wang
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
| | - Chuan-Shu He
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
| | - Gong-Ming Wang
- Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
| | - Yang Mu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry , University of Science & Technology of China , Hefei 230026 , China
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50
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Maza WA, Breslin VM, Plymale NT, DeSario PA, Epshteyn A, Owrutsky JC, Pate BB. Nanosecond transient absorption studies of the pH-dependent hydrated electron quenching by HSO 3. Photochem Photobiol Sci 2019; 18:1526-1532. [PMID: 30984955 DOI: 10.1039/c9pp00063a] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The large standard reduction potential of an aqueous solvated electron (eaq-, E° = -2.9 V) makes it an attractive candidate for reductive treatment of wastewater contaminants. Using transient absorption spectroscopy, the nanosecond to microsecond dynamics of eaq- generated from 10 mM solutions of Na2SO3 at pH 4 to 11 in H2O and D2O are characterized, resulting in the determination that between pH 4 and 9 it is the HSO3-, and not H+ as previously postulated by others, that effectively quenches eaq-. The observed bimolecular quenching rate constant (k = 1.2 × 108 M-1 s-1) for eaq- deactivation by HSO3- is found to be consistent with a Brønsted acid catalysis mechanism resulting in formation of H˙ and SO32-. A large solvent isotope effect is observed from the lifetimes of the eaq- in H2O compared to D2O (kH2O/kD2O = 4.4). In addition, the bimolecular rate constant for eaq- deactivation by DSO3- (k = 2.7 × 107 M-1 s-1) is found to be an order of magnitude lower than by HSO3-. These results highlight the role of acids, such as HSO3-, in competition with organic contaminant targets for eaq- and, by extension, that knowledge of the pKa of eaq- sources can be a predictive measure of the effective pH range for the treatment of wastewater contaminants.
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Affiliation(s)
- William A Maza
- National Research Council, U.S. Naval Research Laboratory, Washington, D.C. 20375, USA.
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