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Zhao R, Chew YMJ, Hofman JAMH, Lutze HV, Wenk J. UV-induced reactive species dynamics and product formation by chlorite. WATER RESEARCH 2024; 264:122218. [PMID: 39121819 DOI: 10.1016/j.watres.2024.122218] [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: 04/05/2024] [Revised: 08/01/2024] [Accepted: 08/03/2024] [Indexed: 08/12/2024]
Abstract
Chlorite (ClO2-) is a regulated byproduct of chlorine dioxide water treatment processes. The transformation of chlorite under UV irradiation into chloride (Cl-) and chlorate (ClO3-) involves reactive species chain reactions that could enhance chlorine dioxide water treatment efficiency while reducing residual chlorite levels. This study conducted a mechanistic investigation of chlorite phototransformation by analyzing reaction intermediates and stable end products, including chlorine dioxide (ClO2), free chlorine (HOCl/OCl-), hydroxyl‑radical (•OH), Cl-, and ClO3- through combined experimental and modeling approaches. Experiments were performed at UV254 irradiation in pure buffered water within the pH range of 6 to 8. Results indicated that the apparent quantum yields for chlorite phototransformation increased from 0.86 to 1.45, and steady-state •OH concentrations at 1 mM initial chlorite concentration rose from 8.16 × 10-14 M - 16.1 × 10-14 M with decreasing pH values. It was observed that under UV irradiation, chlorite acts as both a significant producer and consumer of reactive species through three distinct reaction pathways. The developed kinetic model, which incorporates optimized intrinsic chlorite quantum yields Φchloritein ranging from 0.33 to 0.39, effectively simulated the loss of oxidants and the formation of major products. It also accurately predicted steady-state concentrations of various species, including •OH, •ClO, Cl• and O3. For the first time, this study provides a comprehensive transformation pathway scheme for chlorite phototransformation. The findings offer important insights into the mechanistic aspects of product and oxidizing species formation during chlorite phototransformation.
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Affiliation(s)
- Ranran Zhao
- Department of Chemical Engineering, University of Bath, Bath, BA2 7AY, UK; Water Innovation and Research Centre, University of Bath, BA2 7AY, UK
| | - Y M John Chew
- Department of Chemical Engineering, University of Bath, Bath, BA2 7AY, UK
| | - Jan A M H Hofman
- Department of Chemical Engineering, University of Bath, Bath, BA2 7AY, UK; Water Innovation and Research Centre, University of Bath, BA2 7AY, UK
| | - Holger V Lutze
- Civil- and Environmental Engineering, Institute IWAR, Technical University of Darmstadt, 64287 Darmstadt, Germany; IWW Water Centre, Moritzstrasse 26, 45476, Mülheim an der Ruhr, Germany; Centre for Water and Environmental Research (ZWU), Universitätsstrasse 5, 45141, Essen, Germany.
| | - Jannis Wenk
- Department of Chemical Engineering, University of Bath, Bath, BA2 7AY, UK; Water Innovation and Research Centre, University of Bath, BA2 7AY, UK.
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Sun Y, Sun W, Li Y, Dong N, Yu H, Yin W, Zhu F, Gao B, Xu S. Effective inhibition of chloride ion interference in photocatalytic process by negatively charged molecularly imprinted photocatalyst: Behavior and mechanism. WATER RESEARCH 2024; 262:122040. [PMID: 39018579 DOI: 10.1016/j.watres.2024.122040] [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: 02/01/2024] [Revised: 06/05/2024] [Accepted: 07/02/2024] [Indexed: 07/19/2024]
Abstract
The ubiquitous chloride ions (Cl-) in water seriously interfere with pollutant oxidation and inevitably generate undesirable chlorinated byproducts. In this study, we report for the first time that a negatively charged molecularly imprinted photocatalyst (MIP) can effectively inhibit Cl- interference and suppress the production of chlorination byproducts (the yield of chloroacetic acid was only 16 % of the bare photocatalyst system) while ensuring efficient degradation of target pollutants, thereby greatly improving the safety of the pollutant degradation process. Taking antibiotics as target pollutant, we investigated the mechanism of action of MIP by comparing the antibiotic degradation pathways, fate of photogenerated active species and production of reactive chlorine species (RCS) in the MIP and bare photocatalyst system. The mechanism by which MIP inhibits Cl- interference was mainly based on a synergy between electrostatic repulsion and steric hindrance induced by the specific capture of antibiotics in imprinted cavity, which effectively suppressed the production of RCS and hindered the participation of RCS in antibiotics degradation. In addition, MIP showed good compatibility with common cations, anions and organic matter, and performed well within a broad pH range in various water environments. Thus, the negatively charged MIP provides a feasible approach for the safe and efficient removal of pollutants in Cl- containing water.
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Affiliation(s)
- Yunkai Sun
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Qingdao Key Laboratory of Marine Pollutant Prevention, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Wanting Sun
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Qingdao Key Laboratory of Marine Pollutant Prevention, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Yude Li
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Qingdao Key Laboratory of Marine Pollutant Prevention, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Nannan Dong
- Microbial Technology Institute and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Haiyan Yu
- Microbial Technology Institute and State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266237, China
| | - Weiyan Yin
- Hubei Key Laboratory of Biomass Fibers and Eco-dyeing & Finishing, School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan, 430073, China
| | - Fanping Zhu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Qingdao Key Laboratory of Marine Pollutant Prevention, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Baoyu Gao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Qingdao Key Laboratory of Marine Pollutant Prevention, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China
| | - Shiping Xu
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, Qingdao Key Laboratory of Marine Pollutant Prevention, School of Environmental Science and Engineering, Shandong University, Qingdao, 266237, China.
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3
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Galoppo S, Fenti A, Falco G, Huang Q, Chianese S, Musmarra D, Iovino P. Efficient electrochemical removal of ammoniacal nitrogen from livestock wastewater: The role of the electrode material. Heliyon 2024; 10:e36803. [PMID: 39263129 PMCID: PMC11388747 DOI: 10.1016/j.heliyon.2024.e36803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 07/29/2024] [Accepted: 08/22/2024] [Indexed: 09/13/2024] Open
Abstract
Wastewater from livestock farms contains high concentrations of suspended solids, organic contaminants, and nitrogen compounds, such as ammoniacal nitrogen. Discharging livestock effluents into water bodies without appropriate treatment leads to severe environmental pollution. Compared to conventional treatment methods, electrochemical oxidation exhibits higher nitrogen removal efficiencies. In the present work, the electrochemical removal of ammoniacal nitrogen from real livestock wastewater was investigated through a lab-scale reactor. Preliminary experiments were carried out to investigate the effects of different anode materials, including boron-doped diamond and iridium/ruthenium-coated titanium, on the total nitrogen removal efficiency using synthetic wastewater. Boron-doped diamond, a well-known non-active electrode, allowed to obtain 63.7 ± 1.21 % of total nitrogen degradation efficiency. However, the iridium/ruthenium-coated titanium electrode, belonging to the class of active anodes, showed a higher performance, achieving 78.8 ± 0.76 % contaminant degradation. Coupling iridium/ruthenium-coated titanium anode with a stainless-steel cathode improved the performance of the system, achieving even 96.2 ± 2.73 % of total nitrogen removal. The optimized cell configuration was used to treat livestock wastewater, resulting in the degradation of 67.0 ± 2.25 % of total nitrogen and 37.3 ± 0.68 % of total organic carbon when sodium chloride was added. At the end of the process, the ammonium content was completely removed, and only 17.7 ± 0.51 % of the initial nitrogen turned into nitrate. The results show that the proposed system is a promising approach to treating livestock wastewater by coupling high contaminant removal efficiencies with low operational costs. Anyway, further studies on process optimization with an emphasis on power requirements and electrode costs need to be carried out.
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Affiliation(s)
- Simona Galoppo
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031, Aversa, Italy
| | - Angelo Fenti
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031, Aversa, Italy
| | - Giovanni Falco
- Department of Environmental, Biological and Pharmaceutical Science and Technologies, University of Campania "Luigi Vanvitelli", Via Vivaldi 43, 81100, Caserta, Italy
| | - Qingguo Huang
- College of Agricultural and Environmental Sciences, University of Georgia, Griffin, GA, United States
| | - Simeone Chianese
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031, Aversa, Italy
| | - Dino Musmarra
- Department of Engineering, University of Campania "Luigi Vanvitelli", Via Roma 29, 81031, Aversa, Italy
| | - Pasquale Iovino
- Department of Environmental, Biological and Pharmaceutical Science and Technologies, University of Campania "Luigi Vanvitelli", Via Vivaldi 43, 81100, Caserta, Italy
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de Brito Anton L, Silverman AI, Apell JN. Determining wavelength-dependent quantum yields of photodegradation: importance of experimental setup and reference values for actinometers. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:1052-1063. [PMID: 38713490 DOI: 10.1039/d4em00084f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Accurate quantum yields are crucial for modeling photochemical reactions in natural and engineered treatment systems. Quantum yields are usually determined using a single representative light source such as xenon lamps to mimic sunlight or UVC light for water treatment. However, photodegradation modeling can be improved by understanding the wavelength dependence of quantum yields and the potential errors introduced by the experimental setup. In this study, we investigated the effects of experimental setup on measured quantum yields using four photoreactor systems and up to 11 different light sources. When using a calibrated spectroradiometer to measure incident irradiance on an open solution surface, apparent quantum yields were up to two times higher if light reflection and light screening were not accounted for in the experimental setup. When the experimental setup was optimized to allow for accurate irradiance measurements, quantum yields were reproducible across photoreactors. The optimized experimental setup was then used to determine quantum yields of uridine, atrazine, p-nitroanisole (PNA), sulfamethoxazole, and diclofenac across the UV spectrum. No significant wavelength dependence of quantum yields was observed for sulfamethoxazole and diclofenac, in contrast to wavelength-dependent quantum yields for uridine, atrazine, and PNA. These reference values can be used for determining wavelength-dependent quantum yields of other compounds of interest. Additionally, more accurate results can be obtained when using (1) an actinometer with similar light absorption and photoreactivity compared to that of the target chemical, (2) optically transparent actinometer solutions that can account for light reflection within reaction vessels, and (3) a quantum yield that corresponds to the spectrum of the selected light source.
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Affiliation(s)
- Luana de Brito Anton
- Civil and Urban Engineering Department, Tandon School of Engineering, New York University, Brooklyn, New York 11201, USA.
| | - Andrea I Silverman
- Civil and Urban Engineering Department, Tandon School of Engineering, New York University, Brooklyn, New York 11201, USA.
| | - Jennifer N Apell
- Civil and Urban Engineering Department, Tandon School of Engineering, New York University, Brooklyn, New York 11201, USA.
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Hübner U, Spahr S, Lutze H, Wieland A, Rüting S, Gernjak W, Wenk J. Advanced oxidation processes for water and wastewater treatment - Guidance for systematic future research. Heliyon 2024; 10:e30402. [PMID: 38726145 PMCID: PMC11079112 DOI: 10.1016/j.heliyon.2024.e30402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/23/2024] [Accepted: 04/25/2024] [Indexed: 05/12/2024] Open
Abstract
Advanced oxidation processes (AOPs) are a growing research field with a large variety of different process variants and materials being tested at laboratory scale. However, despite extensive research in recent years and decades, many variants have not been transitioned to pilot- and full-scale operation. One major concern are the inconsistent experimental approaches applied across different studies that impede identification, comparison, and upscaling of the most promising AOPs. The aim of this tutorial review is to streamline future studies on the development of new solutions and materials for advanced oxidation by providing guidance for comparable and scalable oxidation experiments. We discuss recent developments in catalytic, ozone-based, radiation-driven, and other AOPs, and outline future perspectives and research needs. Since standardized experimental procedures are not available for most AOPs, we propose basic rules and key parameters for lab-scale evaluation of new AOPs including selection of suitable probe compounds and scavengers for the measurement of (major) reactive species. A two-phase approach to assess new AOP concepts is proposed, consisting of (i) basic research and proof-of-concept (technology readiness levels (TRL) 1-3), followed by (ii) process development in the intended water matrix including a cost comparison with an established process, applying comparable and scalable parameters such as UV fluence or ozone consumption (TRL 3-5). Subsequent demonstration of the new process (TRL 6-7) is briefly discussed, too. Finally, we highlight important research tools for a thorough mechanistic process evaluation and risk assessment including screening for transformation products that should be based on chemical logic and combined with complementary tools (mass balance, chemical calculations).
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Affiliation(s)
- Uwe Hübner
- Chair of Urban Water Systems Engineering, Technical University of Munich, Am Coulombwall 3, 85748, Garching, Germany
- Xylem Services GmbH, Boschstraße 4-14, 32051, Herford, Germany
| | - Stephanie Spahr
- Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301, 12587, Berlin, Germany
| | - Holger Lutze
- Department of Civil and Environmental Engineering, Institute IWAR, Chair of Environmental Analytics and Pollutants, Technical University of Darmstadt, Franziska-Braun-Straße 7, 64287, Darmstadt, Germany
- IWW Water Centre, Moritzstraße 26, 45476, Mülheim an der Ruhr, Germany
- Centre for Water and Environmental Research (ZWU), Universitätsstraße 5, 45141, Essen, Germany
| | - Arne Wieland
- Xylem Services GmbH, Boschstraße 4-14, 32051, Herford, Germany
| | - Steffen Rüting
- Xylem Services GmbH, Boschstraße 4-14, 32051, Herford, Germany
| | - Wolfgang Gernjak
- Catalan Institute for Water Research (ICRA), 17003, Girona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), 08010, Barcelona, Spain
| | - Jannis Wenk
- University of Bath, Department of Chemical Engineering and Water Innovation & Research Centre (WIRC@Bath), Bath, BA2 7AY, United Kingdom
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6
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Zhong Y, Chen Y, Ong SL, Hu J, Balakrishnan V, Ang WS. Disinfection by-products control in wastewater effluents treated with ozone and biological activated carbon followed by UV/Chlor(am)ine processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 922:171317. [PMID: 38428610 DOI: 10.1016/j.scitotenv.2024.171317] [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: 11/09/2023] [Revised: 02/24/2024] [Accepted: 02/25/2024] [Indexed: 03/03/2024]
Abstract
Sequential utilization of ozone (O3) and biological activated carbon (BAC) followed by UV/chlor(am)ine advanced oxidation process (AOP) has drawn attention in water reuse. However, the formation of disinfection by-products (DBPs) in this process is less evaluated. This study investigated the DBP formation and the relevant toxicity during the O3-BAC-UV/chlor(am)ine treatment of sand-filtered municipal secondary effluent. DBP formation in UV/chlorine and UV/dichloramine (NHCl2) processes were compared, where the impact of key operational parameters (e.g., UV wavelength, pH) on DBP formation were comprehensively evaluated. O3-BAC significantly reduced DBP formation potential (DBPFP) (58.2 %). Compared to UV/chlorine AOP, UV/NHCl2 AOP reduced DBP formation by 29.7 % in short-time treatment, while insignificantly impacting on DBPFP (p > 0.05). UV/NHCl2 AOP also led to lower calculated cytotoxicity (67.7 %) and genotoxicity (55.9 %) of DBPs compared to UV/chlorine AOP. Compared to 254 nm UV light, the utilization of 285 nm UV light decreased the formation of DBPs in wastewater treated with the UV/chlorine AOP and UV/NHCl2 AOP by 31.3 % and 19.2 %, respectively. However, the cytotoxicity and genotoxicity in UV/NHCl2 AOP using 285 nm UV light increased by 83.4 % and 58.5 %, respectively, compared to 254 nm. The concentration of DBPs formed in the UV/NHCl2 AOP at pH 8 was 54.3 % lower than that at pH 7, suggesting a better control of DBPs at alkaline condition. In the presence of bromide, UV/NHCl2 AOP tended to generate more brominated DBPs than UV/chlorine AOP. Overall, UV/NHCl2 AOP resulted in lower concentration and toxicity of DBPs compared to UV/chlorine AOP.
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Affiliation(s)
- Yu Zhong
- Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Yiwei Chen
- Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Say Leong Ong
- Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore
| | - Jiangyong Hu
- Department of Civil & Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore 117576, Singapore.
| | - Viswanath Balakrishnan
- Water Reclamation (Plants) Department, PUB Singapore, 40 Scotts Road, Environment Building, Singapore 228231, Singapore
| | - Wui Seng Ang
- Water Reclamation (Plants) Department, PUB Singapore, 40 Scotts Road, Environment Building, Singapore 228231, Singapore
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7
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von Gunten U. Oxidation processes and me. WATER RESEARCH 2024; 253:121148. [PMID: 38387263 DOI: 10.1016/j.watres.2024.121148] [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: 11/15/2023] [Revised: 01/12/2024] [Accepted: 01/14/2024] [Indexed: 02/24/2024]
Abstract
This publication summarizes my journey in the field of chemical oxidation processes for water treatment over the last 30+ years. Initially, the efficiency of the application of chemical oxidants for micropollutant abatement was assessed by the abatement of the target compounds only. This is controlled by reaction kinetics and therefore, second-order rate constant for these reactions are the pre-requisite to assess the efficiency and feasibility of such processes. Due to the tremendous efforts in this area, we currently have a good experimental data base for second-order rate constants for many chemical oxidants, including radicals. Based on this, predictions can be made for compounds without experimental data with Quantitative Structure Activity Relationships with Hammet/Taft constants or energies of highest occupied molecular orbitals from quantum chemical computations. Chemical oxidation in water treatment has to be economically feasible and therefore, the extent of transformation of micropollutants is often limited and mineralization of target compounds cannot be achieved under realistic conditions. The formation of transformation products from the reactions of the target compounds with chemical oxidants is inherent to oxidation processes and the following questions have evolved over the years: Are the formed transformation products biologically less active than the target compounds? Is there a new toxicity associated with transformation products? Are transformation products more biodegradable than the corresponding target compounds? In addition to the positive effects on water quality related to abatement of micropollutants, chemical oxidants react mainly with water matrix components such as the dissolved organic matter (DOM), bromide and iodide. As a matter of fact, the fraction of oxidants consumed by the DOM is typically > 99%, which makes such processes inherently inefficient. The consequences are loss of oxidation capacity and the formation of organic and inorganic disinfection byproducts also involving bromide and iodide, which can be oxidized to reactive bromine and iodine with their ensuing reactions with DOM. Overall, it has turned out in the last three decades, that chemical oxidation processes are complex to understand and to manage. However, the tremendous research efforts have led to a good understanding of the underlying processes and allow a widespread and optimized application of such processes in water treatment practice such as drinking water, municipal and industrial wastewater and water reuse systems.
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Affiliation(s)
- Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Duebendorf, Switzerland; ENAC, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale, CH-1000, Lausanne, Switzerland.
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8
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Hong W, Zou J, Zhao M, Yan S, Song W. Development of a Five-Chemical-Probe Method to Determine Multiple Radicals Simultaneously in Hydroxyl and Sulfate Radical-Mediated Advanced Oxidation Processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:5616-5626. [PMID: 38471100 DOI: 10.1021/acs.est.4c00669] [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: 03/14/2024]
Abstract
Advanced oxidation processes (AOPs), such as hydroxyl radical (HO•)- and sulfate radical (SO4•-)-mediated oxidation, are attractive technologies used in water and wastewater treatments. To evaluate the treatment efficiencies of AOPs, monitoring the primary radicals (HO• and SO4•-) as well as the secondary radicals generated from the reaction of HO•/SO4•- with water matrices is necessary. Therefore, we developed a novel chemical probe method to examine five key radicals simultaneously, including HO•, SO4•-, Cl•, Cl2•-, and CO3•-. Five probes, including nitrobenzene, para-chlorobenzoic acid, benzoic acid, 2,4,6-trimethylbenzoic acid, and 2,4,6-trimethylphenol, were selected in this study. Their bimolecular reaction rate constants with diverse radicals were first calibrated under the same conditions to minimize systematic errors. Three typical AOPs (UV/H2O2, UV/S2O82-, and UV/HSO5-) were tested to obtain the radical steady-state concentrations. The effects of dissolved organic matter, Br-, and the probe concentration were inspected. Our results suggest that the five-probe method can accurately measure radicals in the HO•- and SO4•--mediated AOPs when the concentration of Br- and DOM are less than 4.0 μM and 15 mgC L-1, respectively. Overall, the five-probe method is a practical and easily accessible method to determine multiple radicals simultaneously.
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Affiliation(s)
- Wenjie Hong
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, P. R. China
| | - Jianmin Zou
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, P. R. China
| | - Mengzhe Zhao
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, P. R. China
| | - Shuwen Yan
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, P. R. China
| | - Weihua Song
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200438, P. R. China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, P. R. China
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Yang X, Ye L, Zhou Y, Peng J, Kong Q. Effects of pH on the triplet state dissolved organic matter induced free available chlorine decay and radical formation. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133268. [PMID: 38113730 DOI: 10.1016/j.jhazmat.2023.133268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 11/21/2023] [Accepted: 12/12/2023] [Indexed: 12/21/2023]
Abstract
Triplet state dissolved organic matter (3DOM*) plays a significant role in inducing oxidant decay and radical generation in light-based advanced oxidation processes. However, the effects of pH still need investigation. This work quantitatively analyzed the pH-dependent free available chlorine (FAC) decay and radical formation (i.e., HO• and Cl•) induced by 3DOM* or triplet state photosensitizer (3PS*). Upon UV irradiation at 254 nm, the decay rate of FAC by 3DOM* or 3PS* was the highest at neutral pH, while those by dark reaction of DOM and the direct photolysis of FAC were the highest at acidic conditions. This is attributed to the variation of FAC species, 3DOM* or 3PS* formation, and the reaction rate constants of FAC with 3DOM* or 3PS* at pH 5.0-10.0. 3DOM* and 3PS* formed increasingly with pH varying from 5.0 to 10.0, while their reactivity with FAC decreased due to the speciation from HOCl to OCl-. Radical formation (i.e., HO• and Cl•) from FAC reaction with 3DOM* or 3PS* occurred at all the testing pH range (5.0-10.0). This work highlighted the pH-dependent role of 3DOM* in oxidant decay and radical formation in treating DOM containing waters through oxidant photolysis. ENVIRONMENTAL IMPLICATIONS: Triplet state dissolved organic matter (3DOM*) plays a significant role in inducing oxidant decay and radical generation in light-based AOPs. This study revealed the effects of pH in 3DOM* induced free available chlorine (FAC) decay and radical formation (i.e., HO• and Cl•). With DOM at 3 mgC L-1, FAC decayed fastest under neutral conditions and radical formation (i.e., HO• and Cl•) was enhanced at 5.0-10.0 due to 3DOM* reaction with FAC. These results highlighted the pH-dependent role of 3DOM* in oxidant transformation and radical formation in treating DOM containing waters by AOPs based on oxidant photolysis.
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Affiliation(s)
- Xin Yang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Lei Ye
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Yangjian Zhou
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Jianglin Peng
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Qingqing Kong
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
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Van Frost SR, White AM, Jauquet JM, Magness AM, McMahon KD, Remucal CK. Laboratory measurements underestimate persistence of the aquatic herbicide fluridone in lakes. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2024; 26:368-379. [PMID: 38189445 DOI: 10.1039/d3em00537b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Fluridone is an aquatic herbicide commonly used to treat invasive freshwater plant species such as Eurasian watermilfoil, hydrilla, and curly-leaf pondweed. However, required exposures times are very long and often exceed 100 days. Thus, understanding the mechanisms that determine the fate of fluridone in lakes is critical for supporting effective herbicide treatments and minimizing impacts to non-target species. We use a combination of laboratory and field studies to quantify fluridone photodegradation, as well as sorption and microbial degradation in water and sediment microcosms. Laboratory irradiation studies demonstrate that fluridone is susceptible to direct photodegradation with negligible indirect photodegradation, with predicted half-lives in sunlight ranging from 2.3 days (1 cm path length) to 118 days (integrated over 1 meter). Biodegradation is attributable to microbes in sediment with an observed half-life of 57 days. Lastly, fluridone sorbs to sediments (Koc = 340 ± 28 L kg-1); sorption accounts for 16% of fluridone loss in the microcosm experiments. While the laboratory results indicate that all three loss pathways can influence fluridone fate, these controlled studies oversimplify herbicide behavior due to their inability to replicate field conditions. Fluridone concentration measurements in a lake following commercial application demonstrate a half-life of >150 days, indicating that the herbicide is very persistent in water. This study illustrates why caution should be used when relying on laboratory studies to predict the fate of pesticides and other polar organic compounds in the environment.
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Affiliation(s)
- Sydney R Van Frost
- Department of Civil and Environmental Engineering, University of Wisconsin - Madison, 660 N. Park St, Madison, WI 53706, USA.
| | - Amber M White
- Environmental Chemistry and Technology Program, University of Wisconsin - Madison, Madison, WI 53706, USA
| | - Josie M Jauquet
- Department of Civil and Environmental Engineering, University of Wisconsin - Madison, 660 N. Park St, Madison, WI 53706, USA.
| | - Angela M Magness
- Department of Bacteriology, University of Wisconsin - Madison, 1550 Linden Drive, Madison, WI 53706, USA.
| | - Katherine D McMahon
- Department of Civil and Environmental Engineering, University of Wisconsin - Madison, 660 N. Park St, Madison, WI 53706, USA.
- Department of Bacteriology, University of Wisconsin - Madison, 1550 Linden Drive, Madison, WI 53706, USA.
| | - Christina K Remucal
- Department of Civil and Environmental Engineering, University of Wisconsin - Madison, 660 N. Park St, Madison, WI 53706, USA.
- Environmental Chemistry and Technology Program, University of Wisconsin - Madison, Madison, WI 53706, USA
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11
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Mostefaoui N, Oturan N, Bouafia SC, Hien SA, Gibert-Vilas M, Lesage G, Pechaud Y, Tassin B, Oturan M, Trellu C. Integration of electrochemical processes in a treatment system for landfill leachates based on a membrane bioreactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:168841. [PMID: 38036133 DOI: 10.1016/j.scitotenv.2023.168841] [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: 08/31/2023] [Revised: 11/16/2023] [Accepted: 11/22/2023] [Indexed: 12/02/2023]
Abstract
The use of electrocoagulation (EC) and anodic oxidation (AO) processes was studied for improving a treatment system for landfill leachates based on a membrane bioreactor (MBR) and a nanofiltration step. The main limitation of the current full-scale system is related to the partial removal of organic compounds that leads to operation of the nanofiltration unit with a highly concentrated feed solution. Application of the EC before the MBR participated in partial removal of the organic load (40 %) with limited energy consumption (2.8 kWh m-3) but with additional production of iron hydroxide sludge. Only AO allowed for non-selective removal of organic compounds. As a standalone process, AO would require a sharp increase of the energy consumption (116 kWh for 81 % removal of total organic carbon). But using lower electric charge and combining AO with EC and MBR processes would allow for achieving high overall removal yields with limited energy consumption. For example, the overall removal yield of total organic carbon was 65 % by application of AO after EC, with an energy consumption of 21 kWh m-3. Results also showed that such treatment strategy might allow for a significant increase of the biodegradability of the effluent before treatment by the MBR. The MBR might then be dedicated to the removal of the residual organic load as well as to the removal of the nitrogen load. The data obtained in this study also showed that the lower electric charge required for integrating AO in a coupled process would allow for strongly decreasing the formation of undesired by-products such as ClO3- and ClO4-.
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Affiliation(s)
- Nabil Mostefaoui
- Université Gustave Eiffel, Laboratoire Géomatériaux et Environnement EA 4508, 77454 Marne-la-Vallée, Cedex 2, France; Laboratory of Reaction Engineering, Faculty of Mechanical Engineering and Process Engineering USTHB, BP 32, El-Allia, Bab-Ezzouar, Algiers 16111, Algeria
| | - Nihal Oturan
- Université Gustave Eiffel, Laboratoire Géomatériaux et Environnement EA 4508, 77454 Marne-la-Vallée, Cedex 2, France
| | - Souad Chergui Bouafia
- Laboratory of Reaction Engineering, Faculty of Mechanical Engineering and Process Engineering USTHB, BP 32, El-Allia, Bab-Ezzouar, Algiers 16111, Algeria
| | - Sié Alain Hien
- Université Gustave Eiffel, Laboratoire Géomatériaux et Environnement EA 4508, 77454 Marne-la-Vallée, Cedex 2, France; Laboratoire des Procédés Industriels, de Synthèse de l'Environnement et des Energies Nouvelles (LAPISEN), Institut National Polytechnique Houphouët-Boigny, BP 1313, Yamoussoukro, Côte d'Ivoire
| | - Màxim Gibert-Vilas
- Université Gustave Eiffel, Laboratoire Géomatériaux et Environnement EA 4508, 77454 Marne-la-Vallée, Cedex 2, France
| | - Geoffroy Lesage
- Institut Européen des Membranes, IEM, UMR 5635, Centre National de la Recherche Scientifique (CNRS), University Montpellier, ENSCM, Place Eugène Bataillon, 34095 Montpellier, France
| | - Yoan Pechaud
- Université Gustave Eiffel, Laboratoire Géomatériaux et Environnement EA 4508, 77454 Marne-la-Vallée, Cedex 2, France
| | - Bruno Tassin
- Laboratoire Eau Environnement et Systèmes Urbains, LEESU, Ecole des Ponts, Université Paris-Est Créteil, 61 avenue du Général de Gaulle, 94010 Créteil Cedex, France
| | - Mehmet Oturan
- Université Gustave Eiffel, Laboratoire Géomatériaux et Environnement EA 4508, 77454 Marne-la-Vallée, Cedex 2, France
| | - Clément Trellu
- Université Gustave Eiffel, Laboratoire Géomatériaux et Environnement EA 4508, 77454 Marne-la-Vallée, Cedex 2, France.
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12
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Pimentel A, Linden KG. Optimizing radical yield from free chlorine with tailored UV light emitting diode emission spectra. WATER RESEARCH 2024; 249:120923. [PMID: 38064784 DOI: 10.1016/j.watres.2023.120923] [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: 07/12/2023] [Revised: 09/29/2023] [Accepted: 11/23/2023] [Indexed: 01/03/2024]
Abstract
Novel UV sources, which do not contain mercury, provide the opportunity for enhancement of current oxidation technologies through spectral optimization, minimizing inefficiencies that currently limit conventional technology. Wastewater reuse is the primary full-scale application of UV advanced oxidation processes (AOPs) in practice but any background absorbance and the low molar absorption by conventional radical promoters (hydrogen peroxide) have historically limited their system efficiency, resulting in the underutilization of photons in a reactor. This bench-scale research evaluated use of longer wavelength UV light emitting diodes (265, 280, and 300 nm) matched with free chlorine to optimize the utilization of photons for advanced oxidation. Free chlorine possesses large absorption bands in the 280 to 300 nm range in basic pH waters which are common in carbon-based reuse and was used to experimentally verify quantum yields of hydroxyl radical generation across the UV LED peak emission wavelengths. pH- and wavelength-dependent fluence-based rate constants were experimentally derived using Nitrobenzene and Benzoic acid as probe compounds and evaluated to determine the contribution of the hydroxyl and chlorine radical. Reclaimed water taken from various advanced treatment steps was treated with this UV LED AOP to investigate how background absorbance affects radical generation and contaminant transformation kinetics. In addition, alternative performance metrics to evaluate hydroxyl radical production at different incident fluence rates and different rates of photon absorption at unique wavelengths across varying background UV absorbance levels were assessed.
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Affiliation(s)
- Anthony Pimentel
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Dr, Boulder, CO 80303, USA
| | - Karl G Linden
- Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder, 4001 Discovery Dr, Boulder, CO 80303, USA.
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13
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Xie Y, Guan D, Deng Y, Sato Y, Luo Y, Chen G. Factors hindering the degradation of pharmaceuticals from human urine in an iron-activated persulfate system. J Environ Sci (China) 2024; 135:130-148. [PMID: 37778790 DOI: 10.1016/j.jes.2022.12.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 10/03/2023]
Abstract
This study investigated the degradation of clofibric acid (CFA), bezafibrate (BZF), and sulfamethoxazole (SMX) in synthetic human urine using a novel mesoporous iron powder-activated persulfate system (mFe-PS system), and identified the factors limiting their degradation in synthetic human urine. A kinetic model was established to expose the radical production in various reaction conditions, and experiments were conducted to verify the modeling results. In the phosphate-containing mFe-PS system, the 120 min removal efficiency of CFA decreased from 95.1% to 76.6% as the phosphate concentration increased from 0.32 to 6.45 mmol/L, but recovered to 90.5% when phosphate concentration increased to 16.10 mmol/L. Meanwhile, the increased concentration of phosphate from 0.32 to 16.10 mmol/L reduced the BZF degradation efficacy from 91.5% to 79.0%, whereas SMX removal improved from 37.3% to 62.9%. The mFe-PS system containing (bi)carbonate, from 4.20 to 166.70 mmol/L, reduced CFA and BZF removal efficiencies from 100% to 76.8% and 80.4%, respectively, and SMX from 83.5% to 56.7% within a 120-min reaction time. In addition, alkaline conditions (pH ≥ 8.0) inhibited CFA and BZF degradations, while nonacidic pH (pH ≥ 7.0) remarkably inhibited SMX degradation. Results of the kinetic model indicated the formation of phosphate (H2PO4·/HPO4·-) and/or carbonate radicals (CO3·-) could limit pharmaceutical removal. The transformation products (TPs) of the pharmaceuticals revealed more incompletely oxidized TPs occurred in the phosphate- and (bi)carbonate-containing mFe-PS systems, and indicated that H2PO4·/HPO4·- mainly degraded pharmaceuticals via a benzene ring-opening reaction while CO3·- preferentially oxidized pharmaceuticals via a hydroxylation reaction.
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Affiliation(s)
- Yiruiwen Xie
- Department of Civil and Environmental Engineering, Water Technology Lab, Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science & Technology, Hong Kong 999077, China
| | - Dao Guan
- Department of Civil and Environmental Engineering, Water Technology Lab, Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science & Technology, Hong Kong 999077, China.
| | - Yangfan Deng
- Department of Civil and Environmental Engineering, Water Technology Lab, Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science & Technology, Hong Kong 999077, China
| | - Yugo Sato
- Department of Civil and Environmental Engineering, Water Technology Lab, Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science & Technology, Hong Kong 999077, China
| | - Yu Luo
- Department of Civil and Environmental Engineering, Water Technology Lab, Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science & Technology, Hong Kong 999077, China
| | - Guanghao Chen
- Department of Civil and Environmental Engineering, Water Technology Lab, Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science & Technology, Hong Kong 999077, China.
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14
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Bulman DM, Milstead RP, Remucal CK. Formation of Targeted and Novel Disinfection Byproducts during Chlorine Photolysis in the Presence of Bromide. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18877-18887. [PMID: 37363941 DOI: 10.1021/acs.est.3c00431] [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: 06/28/2023]
Abstract
Chlorine photolysis is an advanced oxidation process that relies on the combination of direct chlorination by free available chlorine, direct photolysis, and reactive oxidants to transform contaminants. In waters that contain bromide, free available bromine and reactive bromine species can also form. However, little is known about the underlying mechanisms or formation potential of disinfection byproducts (DBPs) under these conditions. We investigated reactive oxidant generation and DBP formation under dark conditions, chlorine photolysis, and radical-quenched chorine photolysis with variable chlorine (0-10 mg-Cl2/L) and bromide (0-2,000 μg/L) concentrations, as well as with free available bromine. Probe loss rates and ozone concentrations increase with chlorine concentration and are minimally impacted by bromide. Radical-mediated processes partially contribute to the formation targeted DBPs (i.e., trihalomethanes, haloacetic acids, haloacetonitriles, chlorate, and bromate), which increase with increasing chlorine concentration. Chlorinated novel DBPs detected by high-resolution mass spectrometry are attributable to a combination of dark chlorination, direct halogenation by reactive chlorine species, and transformation of precursors, whereas novel brominated DBPs are primarily attributable to dark bromination of electron-rich formulas. The formation of targeted and novel DBPs during chlorine photolysis in waters with elevated bromide may limit treatment applications.
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Affiliation(s)
- Devon Manley Bulman
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Reid P Milstead
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Christina K Remucal
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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15
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Zhao J, Shang C, Yin R. A High-Radical-Yield Advanced Oxidation Process Coupling Far-UVC Radiation with Chlorinated Cyanurates for Micropollutant Degradation in Water. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18867-18876. [PMID: 37158565 DOI: 10.1021/acs.est.3c00255] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Increasing the radical yield and reducing energy consumption would enhance the sustainability and competitiveness of advanced oxidation processes (AOPs) for micropollutant degradation in water. We herein report a novel AOP coupling far-UVC radiation at 222 nm with chlorinated cyanurates (termed the UV222/Cl-cyanurates AOP) for radical generation and micropollutant abatement in water. We experimentally determined the concentrations of HO•, Cl•, and ClO• in the UV222/Cl-cyanurates AOP in deionized water and swimming pool water. The radical concentrations are 10-27 times and 4-13 times, respectively, higher than those in the UV254/Cl-cyanurates AOP and the well-documented UV254/chlorine AOP under comparable conditions (e.g., same UV fluence and oxidant dosing). We determined the molar absorption coefficients and innate quantum yields of two chlorine species and two Cl-cyanurates at 222 nm and incorporated these parameters into a kinetic model. The model enables accurate prediction of oxidant photodecay rates as well as the pH impact on radical generation in the UV222/Cl-cyanurates AOP. We predicted the pseudo-first-order degradation rate constants of 25 micropollutants in the UV222/Cl-cyanurates AOP and demonstrated that many micropollutants can be degraded by >80% with a low UV fluence of 25 mJ cm-2. This work advances the fundamental photochemistry of chlorine and Cl-cyanurates at 222 nm and offers a highly effective engineering tool in combating micropollutants in water where Cl-cyanurates are suitable to use.
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Affiliation(s)
- Jing Zhao
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
- Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China
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16
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Li J, Yang T, Zeng G, An L, Jiang J, Ao Z, Ma J. Ozone- and Hydroxyl Radical-Induced Degradation of Micropollutants in a Novel UVA-LED-Activated Periodate Advanced Oxidation Process. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18607-18616. [PMID: 36745772 DOI: 10.1021/acs.est.2c06414] [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: 06/18/2023]
Abstract
In this study, novel light emitting diode (LED)-activated periodate (PI) advanced oxidation process (AOP) at an irradiation wavelength in the ultraviolet A range (UVA, UVA-LED/PI AOP) was developed and investigated using naproxen (NPX) as a model micropollutant. The UVA-LED/PI AOP remarkably enhanced the degradation of NPX and seven other selected micropollutants with the observed pseudo-first-order rate constants ranging from 0.069 ± 0.001 to 4.50 ± 0.145 min-1 at pH 7.0, demonstrating a broad-spectrum micropollutant degradation ability. Lines of evidence from experimental analysis and kinetic modeling confirmed that hydroxyl radical (•OH) and ozone (O3) were the dominant species generated in UVA-LED/PI AOP, and they contributed evenly to NPX degradation. Increasing the pH and irradiation wavelength negatively affected NPX degradation, and this could be well explained by the decreased quantum yield (ΦPI) of PI. The degradation kinetics of NPX by the UVA-LED/PI AOP in the presence of water matrices (i.e., chloride, bicarbonate, and humic acid) and in real waters were examined, and the underlying mechanisms were illustrated. A total of nine transformation products were identified from NPX oxidation by the UVA-LED/PI AOP, mainly via hydroxylation, dealkylation, and oxidation pathways. The UVA-LED/PI AOP proposed might be a promising technology for the treatment of micropollutants in aqueous solutions. The pivotal role of ΦPI during light photolysis of PI may guide the future design of light-assisted PI AOPs.
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Affiliation(s)
- Juan Li
- Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, Zhu Hai519087, People's Republic of China
| | - Tao Yang
- School of Biotechnology and Health Science, Wuyi University, Jiangmen529020, People's Republic of China
| | - Ge Zeng
- School of Biotechnology and Health Science, Wuyi University, Jiangmen529020, People's Republic of China
| | - Linqian An
- School of Biotechnology and Health Science, Wuyi University, Jiangmen529020, People's Republic of China
| | - Jin Jiang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou510006, People's Republic of China
| | - Zhimin Ao
- Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, Zhu Hai519087, People's Republic of China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin150090, People's Republic of China
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17
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Hua Z, Liang J, Wang D, Zhou Z, Fang J. Formation Mechanisms of Nitro Products from Transformation of Aliphatic Amines by UV/Chlorine Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18754-18764. [PMID: 37294018 DOI: 10.1021/acs.est.3c00744] [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: 06/10/2023]
Abstract
Formation of nitrogenous disinfection byproducts from aliphatic amines is a widespread concern owing to the serious health risks associated with them. However, the mechanisms of transforming aliphatic amines and forming nitro products in the UV/chlorine process have rarely been discussed, which are investigated in this work. Initially, secondary amines (R1R2NH) are transformed into secondary organic chloramines (R1R2NCl) via chlorination. Subsequently, radicals, such as HO• and Cl•, are found to contribute predominantly to such transformations. The rate constants at which HO•, Cl•, and Cl2•- react with R1R2NCl are (2.4-5.1) × 109, (1.5-3.8) × 109, and (1.2-6.1) × 107 M-1 s-1, respectively. Consequently, R1R2NCl are transformed into primary amines (R1NH2/R2NH2) and chlorinated primary amines (R1NHCl/R2NHCl and R1NCl2/R2NCl2) by excess chlorine. Furthermore, primarily driven by UV photolysis, chlorinated primary amines can be transformed into nitroalkanes with conversion rates of ∼10%. Dissolved oxygen and free chlorine play crucial roles in forming nitroalkanes, and post-chlorination can further form chloronitroalkanes, such as trichloronitromethane (TCNM). Radicals are involved in forming TCNM in the UV/chlorine process. This study provides new insights into the mechanisms of transforming aliphatic amines and forming nitro products using the UV/chlorine process.
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Affiliation(s)
- Zhechao Hua
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Jieying Liang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Ding Wang
- General Institute of Water Resources and Hydropower Planning and Design, Beijing 100120, China
| | - Zhihong Zhou
- Guangzhou Ecological Environmental Monitoring Center, Guangzhou 510006, China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
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18
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Tang L, Li A, Kong M, Dionysiou DD, Duan X. Effects of wavelength on the treatment of contaminants of emerging concern by UV-assisted homogeneous advanced oxidation/reduction processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 899:165625. [PMID: 37481088 DOI: 10.1016/j.scitotenv.2023.165625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/09/2023] [Accepted: 07/16/2023] [Indexed: 07/24/2023]
Abstract
Pollutants of emerging concern in aqueous environments present a significant threat to both the aquatic ecosystem and human health due to their rapid transfer. Among the various treatment approaches to remove those pollutants, UV-assisted advanced oxidation/reduction processes are considered competent and cost-effective. The treatment effectiveness is highly dependent on the wavelength of the UV irradiation used. This article systematically discusses the wavelength dependency of direct photolysis, UV/peroxides, UV/chlor(am)ine, UV/ClO2, UV/natural organic matter, UV/nitrate, and UV/sulfite on the transformation of contaminants. Altering wavelengths affects the photolysis of target pollutants, photo-decay of the oxidant/reductant, and quantum yields of reactive species generated in the processes, which significantly impact the degradation rates and formation of disinfection byproducts. In general, the degradation of contaminants is most efficient when using wavelengths that closely match the highest molar absorption coefficients of the target pollutants or the oxidizing/reducing agents, and the contribution of pollutant absorption is generally more significant. By matching the wavelength with the peak absorbance of target compounds and oxidants/reductants, researchers and engineers have the potential to optimize the UV wavelengths used in UV-AO/RPs to effectively remove pollutants and control the formation of disinfection byproducts.
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Affiliation(s)
- Liang Tang
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Aozhou Li
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China
| | - Minghao Kong
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221, USA
| | - Dionysios D Dionysiou
- Environmental Engineering and Science Program, Department of Chemical and Environmental Engineering, University of Cincinnati, Cincinnati, OH 45221, USA.
| | - Xiaodi Duan
- Key Laboratory of Organic Compound Pollution Control Engineering (MOE), School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
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19
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Milstead RP, Berg SM, Kelly BM, Knellwolf CD, Larson CJ, Wammer KH, Remucal CK. Limitations of conventional approaches to identify photochemically produced reactive intermediates involved in contaminant indirect photodegradation. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:1694-1707. [PMID: 37728410 PMCID: PMC10591881 DOI: 10.1039/d3em00304c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Dissolved organic matter (DOM) mediated indirect photodegradation can play an important role in the degradation of aquatic contaminants. Predicting the rate of this process requires knowledge of the photochemically produced reactive intermediates (PPRI) that react with the compound of interest, as well as the ability of individual DOM samples to produce PPRI. Key PPRI are typically identified using quencher studies, yet this approach often leads to results that are difficult to interpret. In this work, we analyze the indirect photodegradation of atorvastatin, carbamazepine, sulfadiazine, and benzotriazole using a diverse set of 48 waters from natural and engineered aquatic systems. We use this large data set to evaluate relationships between PPRI formation and indirect photodegradation rate constants, which are directly compared to results using standard quenching experiments. These data demonstrate that triplet state DOM (3DOM) and singlet oxygen (1O2) are critical PPRI for atorvastatin, carbamazepine, and sulfadiazine, while hydroxyl radical (˙OH) contributes to the indirect photodegradation of benzotriazole. We caution against relying on quenching studies because quenching of 3DOM limits the formation of 1O2 and all studied quenchers react with ˙OH. Furthermore, we show that DOM composition directly influences indirect photodegradation and that low molecular weight, microbial-like DOM is positively correlated with the indirect photodegradation rates of carbamazepine, sulfadiazine, and benzotriazole.
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Affiliation(s)
- Reid P Milstead
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, 660 N. Park St., Madison, Wisconsin 53706, USA.
| | - Stephanie M Berg
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, 660 N. Park St., Madison, Wisconsin 53706, USA.
| | - Bella M Kelly
- Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105, USA
| | | | - Cooper J Larson
- Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105, USA
| | - Kristine H Wammer
- Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105, USA
| | - Christina K Remucal
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, 660 N. Park St., Madison, Wisconsin 53706, USA.
- Department of Civil and Environmental Engineering, University of Wisconsin - Madison, Madison, Wisconsin 53706, USA
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20
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Li B, Pan H, Chen B. A review of factors affecting the formation and roles of primary and secondary reactive species in UV 254-based advanced treatment processes. WATER RESEARCH 2023; 244:120537. [PMID: 37683496 DOI: 10.1016/j.watres.2023.120537] [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: 04/06/2023] [Revised: 07/10/2023] [Accepted: 08/27/2023] [Indexed: 09/10/2023]
Abstract
The presence of organic micropollutants (OMPs) in water has been threatening human health and aquatic ecosystems worldwide. Ultraviolet-based advanced treatment processes (UV-ATPs) are one of the most effective and promising technologies to transform OMPs in water; therefore, an increasing number of emerging UV-ATPs are proposed. However, appropriate selection of UV-ATPs for practical applications is challenging because each UV-ATP generates different types and concentrations of reactive species (RSs) that may not be sufficient to degrade specific types of OMPs. Furthermore, the concentrations and types of RSs are highly influenced by anions and dissolved organic matter (DOM) coexisting in real waters, making systematic understandings of their interfering mechanisms difficult. To identify and address the knowledge gaps, this review provides a comparison of the generations and variations of various types of RSs in different UV-ATPs. These analyses not only prove the importance of water matrices on formation and consumption of primary and secondary RSs under different conditions, but also highlight the non-negligible roles of optical properties and reactivities of DOM and anions. For example, different UV-ATPs may be applicable to different target OMPs under different conditions; and the concentrations and roles of secondary RSs may outperform those of primary RSs in OMP degradation for real applications. With continuous progress and outstanding achievements in the UV-ATPs, it is hoped that the findings and conclusions of this review could facilitate further research and application of UV-ATPs.
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Affiliation(s)
- Boqiang Li
- 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
| | - Huimei Pan
- 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
| | - 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.
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21
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White AM, Van Frost SR, Jauquet JM, Magness AM, McMahon KD, Remucal CK. Quantifying the Role of Simultaneous Transformation Pathways in the Fate of the Novel Aquatic Herbicide Florpyrauxifen-Benzyl. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:12421-12430. [PMID: 37552855 DOI: 10.1021/acs.est.3c03343] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/10/2023]
Abstract
Predicting the fate of organic compounds in the environment is challenging due to the inability of laboratory studies to replicate field conditions. We used the intentionally applied aquatic herbicide florpyrauxifen-benzyl (FPB) as a model compound to investigate the contribution of multiple transformation pathways to organic compound fate in lakes. FPB persisted in five Wisconsin lakes for 5-7 days with an in-lake half-life of <2 days. FPB formed four transformation products, with the bioactive product florpyrauxifen persisting up to 30 days post-treatment. Parallel laboratory experiments showed that FPB degrades to florpyrauxifen via base-promoted hydrolysis. Hydroxy-FPB and hydroxy-florpyrauxifen were identified as biodegradation products, while dechloro-FPB was identified as a photoproduct. Material balance calculations using both laboratory rates and field product concentrations demonstrated that hydrolysis (∼47% of loss), biodegradation (∼20%), sorption (∼13%), and photodegradation (∼4%) occurred on similar timescales. Furthermore, the combined results demonstrated that abiotic and plant-catalyzed hydrolysis of FPB to florpyrauxifen, followed by biodegradation of florpyrauxifen to hydroxy-florpyrauxifen, was the dominant transformation pathway in lakes. This study demonstrates how combined field and laboratory studies can be used to elucidate the role of simultaneous and interacting pathways in the fate of organic compounds in aquatic environments.
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Affiliation(s)
- Amber M White
- Environmental Chemistry and Technology Program, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
| | - Sydney R Van Frost
- Department of Civil and Environmental Engineering, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
| | - Josie M Jauquet
- Department of Civil and Environmental Engineering, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
| | - Angela M Magness
- Department of Bacteriology, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
| | - Katherine D McMahon
- Department of Civil and Environmental Engineering, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
- Department of Bacteriology, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
| | - Christina K Remucal
- Environmental Chemistry and Technology Program, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
- Department of Civil and Environmental Engineering, University of Wisconsin─Madison, Madison, Wisconsin 53706, United States
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22
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Milstead RP, Horvath ER, Remucal CK. Dissolved Organic Matter Composition Determines Its Susceptibility to Complete and Partial Photooxidation within Lakes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:11876-11885. [PMID: 37523443 DOI: 10.1021/acs.est.3c01500] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Dissolved organic matter (DOM) plays an important role in carbon cycling within inland surface waters. Under sunlight irradiation, DOM undergoes complete photooxidation to produce carbon dioxide (CO2) and partial photooxidation that alters the molecular composition of DOM. However, a mechanistic understanding of the relationship between DOM composition and its susceptibility to partial and complete photooxidation in surface waters is currently lacking. This work combines light exposure experiments with high-resolution mass spectrometry to investigate DOM photooxidation using two DOM isolates and DOM from 16 lakes that vary in trophic status and size. High ratios of oxygen consumption to dissolved inorganic carbon (DIC) production demonstrate that all samples undergo extensive partial photooxidation. At the molecular level, more oxidized, aromatic DOM formulas are associated with oxygen consumption and DIC production. Bulk level measurements indicate that DOM becomes less aromatic and lower in apparent molecular weight following partial photooxidation, and there is molecular level evidence of oxygen addition and loss of CO2 in all samples. However, formulas most susceptible to photooxidation vary depending on the initial DOM composition. Collectively, this work provides insights into the relationship between DOM composition and photooxidation, which has important implications for carbon cycling in diverse surface waters.
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Affiliation(s)
- Reid P Milstead
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Emma R Horvath
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Christina K Remucal
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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23
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Jiang X, Yuan J, Zheng Z, Tao Y, Wu X. Degradation of Sulfonamides by UV/Electrochemical Oxidation and the Effects of Treated Effluents on the Bacterial Community in Surface Water. ACS OMEGA 2023; 8:28409-28418. [PMID: 37576615 PMCID: PMC10413449 DOI: 10.1021/acsomega.3c02637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 07/11/2023] [Indexed: 08/15/2023]
Abstract
This study evaluated the effects of ultraviolet (UV) photolysis combined with electrochemical oxidation on sulfonamides (SAs) as well as its treated effluent on the bacterial community in surface water. In terms of degradation rate, the best anode material for electrochemical oxidation was Ti/RuO2-IrO2, which had the highest degradation kinetic constant compared to Ti/Ta2O5-IrO2 and Ti/Pt. Experiments showed the highest degradation rate of SAs at 8.3 pH. Similarly, increasing the current leads to stronger degradation due to the promotion of free chlorine production, and its energy consumption rate decreases slightly from 73 to 67 W h/mmol. Compared with tap water, the kinetic constants decreased by 20-62% for SAs in three different surface water samples, which was related to the decrease in free chlorine. When extending the reaction time to 24 h, the concentrations of chemical oxygen demand and total organic carbon decreased by approximately 30-40%, indicating that the SAs and their products could be mineralized. The diversity analysis showed that the effluents influenced the richness and diversity of the bacterial community, particularly in the 4 h sample. Additionally, there were 86 operational taxonomic units common to all samples, excluding the 4 h sample; significant differences were derived from changes in the Actinobacteriota and Bacteroidota phyla. The toxicity of the products might explain these changes, and these products could be mineralized, as observed in the 24 h sample. Therefore, the extension of treatment time would greatly reduce the ecological harm of treated effluent and ensure that the UV/electrochemical process is a feasible treatment option. Overall, this study provides valuable insight into the optimization and feasibility of UV/electrochemical processes as a sustainable treatment option for sulfonamide-contaminated water sources, emphasizing the importance of considering ecological impacts and the need for extended treatment times that address environmental concerns and ensuring improved water quality.
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Affiliation(s)
- Xinwei Jiang
- School
of Urban Construction, Yangtze University, Jingzhou 434023, China
| | - Julin Yuan
- Key
Laboratory of Healthy Freshwater Aquaculture, Ministry of Agriculture
and Rural Affairs; Key Laboratory of Fish Health and Nutrition of
Zhejiang Province, Zhejiang Institute of
Freshwater Fisheries, Huzhou 313001, China
| | - Zhijie Zheng
- School
of Urban Construction, Yangtze University, Jingzhou 434023, China
| | - Yufang Tao
- College
of Chemistry & Environmental Engineering, Yangtze University, Jingzhou 434023, China
| | - Xiaogang Wu
- School
of Urban Construction, Yangtze University, Jingzhou 434023, China
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24
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Kong Q, Ye L, Pan Y, Zhou Y, Lei Y, Zeng Z, Chen S, Yao L, Zhang X, Westerhoff P, Yang X. Photochemical Transformation of Free Chlorine Induced by Triplet State Dissolved Organic Matter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37428984 DOI: 10.1021/acs.est.3c02458] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
Photolysis of free chlorine is an increasingly recognized approach for effectively inactivating microorganisms and eliminating trace organic contaminants. However, the impact of dissolved organic matter (DOM), which is ubiquitous in engineered water systems, on free chlorine photolysis is not yet well understood. In this study, triplet state DOM (3DOM*) was found to cause the decay of free chlorine for the first time. By using laser flash photolysis, the scavenging rate constants of triplet state model photosensitizers by free chlorine at pH 7.0 were determined to be in the range of (0.26-3.33) × 109 M-1 s-1. 3DOM*, acting as a reductant, reacted with free chlorine at an estimated reaction rate constant of 1.22(±0.22) × 109 M-1 s-1 at pH 7.0. This study revealed an overlooked pathway of free chlorine decay during UV irradiation in the presence of DOM. Besides the DOM's light screening ability and scavenging of radicals or free chlorine, 3DOM* played an important role in the decay of free chlorine. This reaction pathway accounted for a significant proportion of the decay of free chlorine, ranging from 23 to 45%, even when DOM concentrations were below 3 mgC L-1 and a free chlorine dose of 70 μM was present during UV irradiation at 254 nm. The generation of HO• and Cl• from the oxidation of 3DOM* by free chlorine was confirmed by electron paramagnetic resonance and quantified by chemical probes. By inputting the newly observed pathway in the kinetics model, the decay of free chlorine in UV254-irradiated DOM solution can be well predicted.
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Affiliation(s)
- Qingqing Kong
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Lei Ye
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Yanheng Pan
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Yangjian Zhou
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Yu Lei
- Key Laboratory of Photochemistry, Institute of Chemistry Chinese Academy of Sciences, Beijing National Laboratory for Molecular Sciences, Beijing 100190, China
| | - Zihan Zeng
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Siqi Chen
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Liaoliao Yao
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Xinran Zhang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Paul Westerhoff
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona 85287-3005, United States
| | - Xin Yang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
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25
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Sánchez-Montes I, Santos GOS, Dos Santos AJ, Fernandes CHM, Souto RS, Chelme-Ayala P, El-Din MG, Lanza MRV. Toxicological aspect of water treated by chlorine-based advanced oxidation processes: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 878:163047. [PMID: 36958544 DOI: 10.1016/j.scitotenv.2023.163047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 05/13/2023]
Abstract
As well established in the literature, residual toxicity is an important parameter for evaluating the sanitary and environmental safety of water treatment processes, and this parameter becomes even more crucial when chlorine-based processes are applied for water treatment. Eliminating initial toxicity or preventing its increase after water treatment remains a huge challenge mainly due to the formation of highly toxic disinfection by-products (DBPs) that stem from the degradation of organic contaminants or the interaction of the chlorine-based oxidants with different matrix components. In this review, we present a comprehensive discussion regarding the toxicological aspects of water treated using chlorine-based advanced oxidation processes (AOPs) and the recent findings related to the factors influencing toxicity, and provide directions for future research in the area. The review begins by shedding light on the advances made in the application of free chlorine AOPs and the findings from studies conducted using electrochemical technologies based on free chlorine generation. We then delve into the insights and contributions brought to the fore regarding the application of NH2Cl- and ClO2-based treatment processes. Finally, we broaden our discussion by evaluating the toxicological assays and predictive models employed in the study of residual toxicity and provide an overview of the findings reported to date on this subject matter, while giving useful insights and directions for future research on the topic.
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Affiliation(s)
- Isaac Sánchez-Montes
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil; Department of Civil and Environmental Engineering, University of Alberta, T6G 1H9 Edmonton, AB, Canada.
| | - Géssica O S Santos
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Alexsandro J Dos Santos
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Carlos H M Fernandes
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Robson S Souto
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil
| | - Pamela Chelme-Ayala
- Department of Civil and Environmental Engineering, University of Alberta, T6G 1H9 Edmonton, AB, Canada
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, T6G 1H9 Edmonton, AB, Canada
| | - Marcos R V Lanza
- São Carlos Institute of Chemistry, University of São Paulo, 13560-970 São Carlos, SP, Brazil.
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26
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Zhang Y, Guo Y, Fang J, Guo K, Yu G, Wang Y. Characterization of UV/chlorine process for micropollutant abatement by probe compound-based kinetic models. WATER RESEARCH 2023; 237:119985. [PMID: 37098285 DOI: 10.1016/j.watres.2023.119985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/05/2023] [Accepted: 04/18/2023] [Indexed: 05/09/2023]
Abstract
Micropollutant (MP) abatement efficiencies are critical information for optimizing water treatment process for cost-effective operations. Nevertheless, due to the vast number of MPs in real water matrices, it is infeasible to measure their abatement efficiencies individually in practical applications. In this study, a probe compound-based kinetic model was developed for generalized prediction of MP abatement in various water matrices by the ultraviolet (UV)/chlorine process. The results show that by measuring the depletion of three probe compounds (ibuprofen, primidone, and dimetridazole) spiked in the water matrix, the exposures of main reactive chlorine species (RCS including chlorine radicals (Cl•), dichloride radicals (Cl2-•) and chlorine oxide radicals (ClO•)) and hydroxyl radicals (•OH) during the UV/chlorine process could be calculated using the model. Based on the determined exposures, the abatement efficiencies of various MPs in different water matrices (e.g., surface water, groundwater, and wastewater) could generally be predicted with acceptable accuracy by the model without prior water-specific calibration. In addition, the relative contribution of UV photolysis and oxidation with active chlorine, RCS, and •OH to MP abatement could be quantitatively simulated using the model to clarify the abatement mechanism of MPs during the UV/chlorine process. The probe-based kinetic model can thus offer a useful tool to guide practical water and wastewater treatment for MP abatement and to explore the mechanism of UV/chlorine process.
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Affiliation(s)
- Yinqiao Zhang
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, 100084 Beijing, China; School of Engineering, China Pharmaceutical University, 211198 Nanjing, China
| | - Yang Guo
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, 100084 Beijing, China
| | - Jingyun Fang
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China
| | - Kaiheng Guo
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China
| | - Gang Yu
- Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, 519087 Zhuhai, China
| | - Yujue Wang
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, 100084 Beijing, China.
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27
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Zhang Y, Hua Z, Zhang X, Guo K, Fang J. Unexpected trends for the formation of chlorate and bromate during the photolysis of chlorine in bromide-containing water. WATER RESEARCH 2023; 240:120100. [PMID: 37247439 DOI: 10.1016/j.watres.2023.120100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 04/06/2023] [Accepted: 05/17/2023] [Indexed: 05/31/2023]
Abstract
Solar photolysis of free chlorine (solar/chlorine) in bromide-containing water occurs under various scenarios, such as chlorinated reservoirs and outdoor swimming pools, and the formation of chlorate and bromate is an important issue in the system. We reported unexpected trends for the formation of chlorate and bromate in the solar/chlorine system. Excess chlorine inhibited the formation of bromate, i.e., increasing chlorine dosages from 50 to 100 μM reduced the bromate yield from 6.4 to 1.2 μM in solar/chlorine at 50 μM bromide and pH 7. The yield of bromate in solar/chlorine at 100 μM chlorine and 50 μM bromide in 240 min was 18.8% of that at 50 μM bromine only. The underlying mechanism was that HOCl can react with bromite (BrO2-) to form HOClOBrO-, whose multi-step transformation finally formed chlorate as the major product and bromate as the minor product. This reaction overwhelmed the oxidation of bromite to form bromate by reactive species, such as •OH, BrO• and ozone. On the other hand, the presence of bromide greatly enhanced the formation of chlorate. Increasing bromide concentrations from 0 to 50 μM enhanced the chlorate yields from 2.2 to 7.0 μM at 100 μM chlorine. The absorbance of bromine was higher than that of chlorine, thus the photolysis of bromine formed higher levels of bromite at higher bromide concentrations. Then, bromite rapidly reacted with HOCl to form HOClOBrO- and it further transformed to chlorate. Additionally, 1 mg L-1 NOM had a negligible effect on bromate yields in solar/chlorine at 50 μM bromide, 100 μM chlorine and pH 7. This study demonstrated a new pathway of chlorate and bromate formation in the solar/chlorine system with bromide.
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Affiliation(s)
- Yifei Zhang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Zhechao Hua
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Xuewen Zhang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Kaiheng Guo
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, PR China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, PR China.
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28
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Qiu J, Wang J, Ren M, Yang X, Zhang J, Zhang X, Cao H, Xie Y. Comprehensive effect of water matrix on catalytic ozonation of chloride contained saline wastewater. WATER RESEARCH 2023; 234:119827. [PMID: 36889089 DOI: 10.1016/j.watres.2023.119827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 02/04/2023] [Accepted: 02/27/2023] [Indexed: 06/18/2023]
Abstract
Chloride ion (Cl-) is one of the most common anions in wastewater and saline wastewater, but its elusive effects on organics degradation are not clear yet in many cases. In this paper, the effect of Cl- on organic compounds degradation is intensively studied in catalytic ozonation of different water matrix. It was found that the effect of Cl- is almost completely reflected by transforming ·OH to reactive chlorine species (RCS), which is simultaneously competitive with organics degradation. The competition between organics and Cl- for ·OH directly determines the ratio of their consumption rate of ·OH, which depends on their concentration and reactivity with ·OH. Especially, the concentration of organics and solution pH may change greatly during organics degradation process, which will correspondingly influence the transformation rate of ·OH to RCS. Therefore, the effect of Cl- on organics degradation is not immutable, and may dynamically change. As the reaction product between Cl- and ·OH, RCS was also expected to affect the degradation of organics. But we found that Cl· had no significant contribution to the degradation of organics in catalytic ozonation, which may due to its reaction with ozone. Catalytic ozonation of a series of benzoic acid (BA) with different substituents in chloride contained wastewater was also investigated, and the results showed that the electron-donating substituents can weaken the inhibition of Cl- on BAs degradation, because they increase the reactivity of organics with ·OH, O3 and RCS.
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Affiliation(s)
- Jiakai Qiu
- State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization, Pangang Group Research Institute Co., Ltd., Panzhihua, 617000, China; School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Chemistry & Chemical Engineering Data Center, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Jing Wang
- Chemistry & Chemical Engineering Data Center, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Mingzhu Ren
- Chemistry & Chemical Engineering Data Center, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Xin Yang
- School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Jianbo Zhang
- State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization, Pangang Group Research Institute Co., Ltd., Panzhihua, 617000, China
| | - Xiaolong Zhang
- State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization, Pangang Group Research Institute Co., Ltd., Panzhihua, 617000, China
| | - Hongbin Cao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China; Chemistry & Chemical Engineering Data Center, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Yongbing Xie
- State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization, Pangang Group Research Institute Co., Ltd., Panzhihua, 617000, China; Chemistry & Chemical Engineering Data Center, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China.
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29
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Mackey E, Hofmann R, Festger A, Vanyo C, Moore N, Chen T, Wang C, Taylor-Edmonds L, Andrews S. UV-chlorine advanced oxidation for potable water reuse: A review of the current state of the art and research needs. WATER RESEARCH X 2023; 19:100183. [PMID: 37292177 PMCID: PMC10245334 DOI: 10.1016/j.wroa.2023.100183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/22/2023] [Accepted: 05/23/2023] [Indexed: 06/10/2023]
Abstract
This paper reports conclusions from a recent study completed for the Water Research Foundation and the State of California to offer guidance on UV-chlorine advanced oxidation for potable water reuse. The fundamentals of UV-chlorine advanced oxidation are discussed, and lessons learned from some of the early adopters of this technology are presented. Important highlights include the significant impact of ammonia and chloramines on UV-chlorine treatment, challenges associated with predicting UV-chlorine performance due to complex photochemistry, and an ongoing need to monitor potential byproducts and transformation products when employing any form of advanced oxidation for potable reuse.
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Affiliation(s)
- E. Mackey
- Brown and Caldwell, 201N Civic Dr. #300, Walnut Creek, CA 94596, USA
| | - R. Hofmann
- University of Toronto, 35St. George Street, Ontario M5S 1A4, Canada
| | - A. Festger
- Brown and Caldwell, 2N. Central Ave, Phoenix, AZ 85004, USA
| | - C. Vanyo
- Hazen & Sawyer, 1400 E Southern Ave Suite 340, Tempe, AZ 85282, USA
| | - N. Moore
- Department of Civil and Mineral Engineering, University of Toronto, 35St. George Street, Toronto, Ontario M5S 1A4, Canada
| | - T. Chen
- University of Toronto, 35St. George Street, Ontario M5S 1A4, Canada
| | - C. Wang
- Department of Civil Engineering, University of Manitoba, 15 Gillson Street, Winnipeg, Manitoba R3T 5V6, Canada
| | | | - S.A. Andrews
- University of Toronto, 35St. George Street, Ontario M5S 1A4, Canada
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30
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Chen C, Zhao X, Chen H, Li M, Cao L, Wang Y, Xian Q. Degradation of natural organic matter and disinfection byproducts formation by solar photolysis of free available chlorine. WATER RESEARCH 2023; 239:120020. [PMID: 37167852 PMCID: PMC10149525 DOI: 10.1016/j.watres.2023.120020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 04/26/2023] [Accepted: 04/29/2023] [Indexed: 05/13/2023]
Abstract
Environment disinfection effectively curbs transmission of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). However, elevated concentration of free available chlorine (FAC) in disinfectants can be discharged into surface water, generating toxic disinfection byproducts (DBPs). The impact of solar photolysis of FAC on natural organic matter (NOM) to form DBPs has not been well studied. In this work, solar photolysis of FAC was found to result in higher formation of DBPs, DBPs formation potential (DBPsFP), total organic chlorine (TOCl) and lower specific ultraviolet absorbance at 254 nm (SUVA254), compared to dark chlorination. In solar photolysis of FAC, formation of total DBPs was promoted by pH=8, but hindered by the addition of HCO3-, radical scavenger or deoxygenation, while addition of NO3-and NH4+both enhanced the formation of nitrogenous DBPs. Differences in the formation of DBPs in solar photolysis of FAC under various conditions were influenced by reactive species. The formation of trichloromethane (TCM) and haloacetic acids (HAAs) in solar photolysis of FAC positively correlated with the steady-state concentrations of ClO• and O3. The steady-state concentrations of •NO and •NH2 positively correlated with the formation of halonitromethanes (HNMs). HAAs and haloacetonitriles (HANs) mainly contributed to calculated cytotoxicity of DBPs. This study demonstrates that solar photolysis of FAC may significantly impact the formation of DBPs in surface water due to extensive use of disinfectants containing FAC during SARS-CoV-2 pandemic.
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Affiliation(s)
- Chuze Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Xiating Zhao
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Haoran Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Mengting Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Liu Cao
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Yuting Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China
| | - Qiming Xian
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
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31
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Berg SM, Wammer KH, Remucal CK. Dissolved Organic Matter Photoreactivity Is Determined by Its Optical Properties, Redox Activity, and Molecular Composition. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6703-6711. [PMID: 37039298 PMCID: PMC11095828 DOI: 10.1021/acs.est.3c01157] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Predicting the formation of photochemically produced reactive intermediates (PPRI) during the irradiation of dissolved organic matter (DOM) has remained challenging given the complex nature of this material and differences in PPRI formation mechanisms. We investigate the role of DOM composition in photoreactivity using 48 samples that span the range of DOM in freshwater systems and wastewater. We relate quantum yields for excited triplet-state organic matter (fTMP), singlet oxygen (Φ1O2), and hydroxylating species (Φ•OH) to DOM composition determined using spectroscopy, Fourier-transform ion cyclotron resonance mass spectrometry, and electron-donating capacity (EDC). fTMP and Φ1O2 follow similar trends and are correlated with bulk properties derived from UV-vis spectra and EDC. In contrast, no individual bulk property can be used to predict Φ•OH. At the molecular level, the subset of DOM that is positively correlated to both Φ•OH and EDC is distinct from DOM formulas related to Φ1O2, demonstrating that •OH and 1O2 are formed from different DOM fractions. Multiple linear regressions are used to relate quantum yields of each PPRI to DOM composition parameters derived from multiple techniques, demonstrating that complementary methods are ideal for characterizing DOM because each technique only samples a subset of DOM.
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Affiliation(s)
- Stephanie M. Berg
- Environmental Chemistry and Technology Program, University of Wisconsin – Madison, Madison, Wisconsin 53706
| | - Kristine H. Wammer
- Department of Chemistry, University of St. Thomas, St. Paul, Minnesota 55105
| | - Christina K. Remucal
- Environmental Chemistry and Technology Program, University of Wisconsin – Madison, Madison, Wisconsin 53706
- Department of Civil and Environmental Engineering, University of Wisconsin – Madison, Madison, Wisconsin 53706
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Yang T, Zhu M, An L, Zeng G, Fan C, Li J, Jiang J, Ma J. Photolysis of chlorite by solar light: An overlooked mitigation pathway for chlorite and micropollutants. WATER RESEARCH 2023; 233:119809. [PMID: 36878179 DOI: 10.1016/j.watres.2023.119809] [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: 10/06/2022] [Revised: 02/14/2023] [Accepted: 02/24/2023] [Indexed: 06/18/2023]
Abstract
Chlorite (ClO2-) is an undesirable toxic byproduct commonly produced in the chlorine dioxide and ultraviolet/chlorine dioxide oxidation processes. Various methods have been developed to remove ClO2- but require additional chemicals or energy input. In this study, an overlooked mitigation pathway of ClO2- by solar light photolysis with a bonus for simultaneous removal of micropollutant co-present was reported. ClO2- could be efficiently decomposed to chloride (Cl-) and chlorate by simulated solar light (SSL) at water-relevant pHs with Cl- yield up to 65% at neutral pH. Multiple reactive species including hydroxyl radical (•OH), ozone (O3), chloride radical (Cl•), and chlorine oxide radical (ClO•) were generated in the SSL/ClO2- system with the steady-state concentrations following the order of O3 (≈ 0.8 μΜ) > ClO• (≈ 4.4 × 10-6 μΜ)> •OH (≈ 1.1 × 10-7 μΜ)> Cl• (≈ 6.8 × 10-8 μΜ) at neutral pH under investigated condition. Bezafibrate (BZF) as well as the selected six other micropollutants was efficiently degraded by the SSL/ClO2- system with pseudofirst-order rate constants ranging from 0.057 to 0.21 min-1 at pH 7.0, while most of them were negligibly degraded by SSL or ClO2- treatment alone. Kinetic modeling of BZF degradation by SSL/ClO2- at pHs 6.0 - 8.0 suggested that •OH contributed the most, followed by Cl•, O3, and ClO•. The presence of water background components (i.e., humic acid, bicarbonate, and chloride) exhibited negative effects on BZF degradation by the SSL/ClO2- system, mainly due to their competitive scavenging of reactive species therein. The mitigation of ClO2- and BZF under photolysis by natural solar light or in realistic waters was also confirmed. This study discovered an overlooked natural mitigation pathway for ClO2- and micropollutants, which has significant implications for understanding their fate in natural environments.
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Affiliation(s)
- Tao Yang
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Mengyang Zhu
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Linqian An
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Ge Zeng
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Chengqian Fan
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Juan Li
- Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, Zhu Hai 519087, China.
| | - Jin Jiang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China
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Wang YH, Chuang YH, Lin AYC. Evolution of reactive species and their contribution to the removal of ketamine and amine-containing pharmaceuticals during the sunlight/chlorine process. WATER RESEARCH 2023; 233:119738. [PMID: 36858017 DOI: 10.1016/j.watres.2023.119738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 02/11/2023] [Indexed: 06/18/2023]
Abstract
Sunlight-induced photoirradiation of chlorine (sunlight/chlorine) can be observed in outdoor swimming pools and open-channel disinfection units for wastewater treatment. In this study, the degradation of ketamine, an environmentally persistent pharmaceutical, under sunlight irradiation in the presence of a low concentration of chlorine (1 mg/L as Cl2) was investigated to elucidate the evolution of reactive species and their contribution to ketamine removal. •OH dominates the initial stage of sunlight/chlorine; however, after chlorine depletion, reactions still progress with an observed rate constant (kobs = 7.6 ± 0.50 × 10-3 min-1) an order of magnitude higher than photolysis alone (kobs = 2.9 ± 0.15 × 10-4 min-1). When chlorine is depleted, O3 becomes the major reactant that degrades ketamine. High O3 yields were found in both sunlight/HOCl (12.5 ± 0.5% at pH 5) and sunlight/ClO- (10 ± 1% at pH 10) systems. At sub-µM levels, O3 resulted in substantial removal of ketamine, and even faster rates were observed in the presence of sunlight. A kinetic model was also established, and evaluate time-dependent concentration levels during sunlight/chlorine. The model simulation showed that the cumulative O3 concentration could reach 0.91 μM, and O3 contributed 31% ketamine removal during the sunlight/chlorine process. Primary and secondary amine functional groups were demonstrated to be the reaction sites of O3; other pharmaceuticals, such as atenolol and metoprolol, underwent similar phenomena. In addition, the experimental and model results further indicated that sunlight/ClO2- or ClO2 also participates in the degradation of ketamine with a minor role; trace amounts (below nM level) of ClO2- and ClO2 were estimated by the simulation.
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Affiliation(s)
- Yu-Hsiang Wang
- Graduate Institute of Environmental Engineering, National Taiwan University. No. 1, Section 4, Roosevelt Rd, Da'an District, Taipei City, Taiwan 106
| | - Yi-Hsueh Chuang
- Institute of Environmental Engineering, National Yang Ming Chiao Tung University. 1001 University Rd., East District, Hsinchu City, Taiwan 300.
| | - Angela Yu-Chen Lin
- Graduate Institute of Environmental Engineering, National Taiwan University. No. 1, Section 4, Roosevelt Rd, Da'an District, Taipei City, Taiwan 106.
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Lei Y, Yu Y, Lei X, Liang X, Cheng S, Ouyang G, Yang X. Assessing the Use of Probes and Quenchers for Understanding the Reactive Species in Advanced Oxidation Processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5433-5444. [PMID: 36930043 DOI: 10.1021/acs.est.2c09338] [Citation(s) in RCA: 63] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Advanced oxidation processes (AOPs) are increasingly applied in water and wastewater treatment. Understanding the role of reactive species using probes and quenchers is one of the main requirements for good process design. However, much fundamental kinetic data for the reactions of probes and quenchers with reactive species is lacking, probably leading to inappropriate probe and quencher selection and dosing. In this work, second-order rate constants for over 150 reactions of probes and quenchers with reactive species such as •OH, SO4•-, and Cl• and chemical oxidants such as free chlorine and persulfate were determined. Some previously ill-quantified reactions (e.g., furfuryl alcohol and methyl phenyl sulfoxide reactions with certain chemical oxidants, nitrobenzene and 1,4-dioxane reactions with certain halogen radicals) were found to be kinetically favorable. The selection of specific probes can be guided by the improved kinetic database. The criteria for properly choosing dosages of probes and quenchers were proposed along with a procedure for quantifying reactive species free of interference from probe addition. The limitations of probe and quencher approaches were explicated, and possible solutions (e.g., the combination with other tools) were proposed. Overall, the kinetic database and protocols provided in this work benefit future research in understanding the radical chemistry in AOPs as well as other radical-involved processes.
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Affiliation(s)
- Yu Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, P. R. China
- Key Laboratory of Photochemistry, Institute of Chemistry Chinese Academy of Sciences, Beijing National Laboratory for Molecular Sciences, Beijing 100190, P. R. China
| | - Yafei Yu
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Xin Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Xi Liang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - ShuangShuang Cheng
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, P. R. China
| | - Gangfeng Ouyang
- School of Chemistry, Sun Yat-sen University, Guangzhou 510275, P. R. 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, P. R. China
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Kiyemba H, Barasa B, Asaba J, Makoba Gudoyi P, Akello G. Water Hyacinth’s Extent and Its Implication on Water Quality in Lake Victoria, Uganda. ScientificWorldJournal 2023; 2023:4947272. [PMID: 37035537 PMCID: PMC10081902 DOI: 10.1155/2023/4947272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 03/03/2023] [Accepted: 03/08/2023] [Indexed: 04/03/2023] Open
Abstract
Water hyacinth (Eichhornia crassipes) degrades and obstructs the integrity of freshwater ecosystems. However, little attention has been paid to monitoring water hyacinth’s spatial extent, its determinants, and its effects on water quality in Lake Victoria, Uganda. The specific objectives of this paper are to (i) assess the spatial extent and distribution of water hyacinth; (ii) examine the determinants of water hyacinth distribution, and (iii) assess its impact on water quality. High-resolution satellite images (2016–2019) were obtained and used to monitor the spatial extent of the water hyacinth, a household survey was conducted to examine the determinants of the water hyacinth’s extent and patterns while water samples were drawn and analysed for physicochemical properties. Results show that the coverage and distribution of water hyacinth varied over space and time. Water hyacinth coverage primarily increased with a decrease in water surface area. The perceived factors that triggered the water hyacinth spread included the morphology of the Bay, effluent discharge, strong winds, speed of water current, water-level changes, ferry navigation, and construction activities at the shore. Water parameters significantly impacted by hyacinth were pH, TP, BOD, COD, DO, turbidity, and transparency. This study recommends the strict development and implementation of integrated weed control measures, catchment management plans, and point and nonpoint pollution source control.
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36
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Medel A, González MC, Treviño-Reséndez J, Meas Y, Bedolla-Valdez ZI, Lara-Jacobo LR, Alonso-Núñez G, Méndez E. Synergistic role of active chlorine species and hydroxyl radicals during disinfection and mineralization of carwash wastewater. J Solid State Electrochem 2023. [DOI: 10.1007/s10008-023-05459-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
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37
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Li M, Durkin DP, Waller G, Yu Y, Men Y, Ye T, Chen H, Shuai D. Transformation of Graphitic Carbon Nitride by Reactive Chlorine Species: "Weak" Oxidants Are the Main Players. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:2749-2757. [PMID: 36745632 DOI: 10.1021/acs.est.2c06381] [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: 06/18/2023]
Abstract
Graphitic carbon nitride (g-C3N4) nanomaterials hold great promise in diverse applications; however, their stability in engineering systems and transformation in nature are largely underexplored. We evaluated the stability, aging, and environmental impact of g-C3N4 nanosheets under the attack of free chlorine and reactive chlorine species (RCS), a widely used oxidant/disinfectant and a class of ubiquitous radical species, respectively. g-C3N4 nanosheets were slowly oxidized by free chlorine even at a high concentration of 200-1200 mg L-1, but they decomposed rapidly when ClO· and/or Cl2•- were the key oxidants. Though Cl2•- and ClO· are considered weaker oxidants in previous studies due to their lower reduction potentials and slower reaction kinetics than ·OH and Cl·, our study highlighted that their electrophilic attack efficacy on g-C3N4 nanosheets was on par with ·OH and much higher than Cl·. A trace level of covalently bonded Cl (0.28-0.55 at%) was introduced to g-C3N4 nanosheets after free chlorine and RCS oxidation. Our study elucidates the environmental fate and transformation of g-C3N4 nanosheets, particularly under the oxidation of chlorine-containing species, and it also provides guidelines for designing reactive, robust, and safe nanomaterials for engineering applications.
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Affiliation(s)
- Mengqiao Li
- Department of Civil and Environmental Engineering, The George Washington University, Washington, D.C.20052, United States
| | - David P Durkin
- Department of Chemistry, United States Naval Academy, Annapolis, Maryland21402, United States
| | - Gordon Waller
- Chemistry Division, United States Naval Research Laboratory, Washington, D.C.20375, United States
| | - Yaochun Yu
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California92521, United States
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois61801, United States
| | - Yujie Men
- Department of Chemical and Environmental Engineering, University of California, Riverside, Riverside, California92521, United States
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois61801, United States
| | - Tao Ye
- Department of Civil and Environmental Engineering, South Dakota School of Mines & Technology, Rapid City, South Dakota57701, United States
| | - Hanning Chen
- Texas Advanced Computing Center, the University of Texas at Austin, Austin, Texas78758, United States
| | - Danmeng Shuai
- Department of Civil and Environmental Engineering, The George Washington University, Washington, D.C.20052, United States
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38
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Velo-Gala I, Farré MJ, Radjenovic J, Gernjak W. Influence of water matrix components on the UV/chlorine process and its reactions mechanism. ENVIRONMENTAL RESEARCH 2023; 218:114945. [PMID: 36463999 DOI: 10.1016/j.envres.2022.114945] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 11/15/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
The UV/chlorine system has become an attractive alternative Advanced Oxidation Process (AOP) for the removal of recalcitrant pollutants in the last decade due to the simultaneous formation of chlorine and hydroxyl radicals. However, there is no consensus regarding the results and trends obtained in previous micropollutant removal studies by AOPs, highlighting the complexity of the UV/chlorine process and the need for further research. This study investigates the degradation of acetaminophen (ACTP) by UV/chlorine and the effects of the water matrix in the reaction kinetics. In particular, the effects of natural organic matter (NOM), alkalinity and mineral salts on the kinetics and reactive species were elucidated. The complexity of the system was revealed by the analysis of the radical generation and transformation in different water matrices, applying the kinetic modelling approach to complement the scavenger tests. The higher kinetic rates of ACTP at alkaline pH provided new insights into the chlorine reactions under UV radiation, where secondary and tertiary reactive oxygen species including ozone were proven to play the major role in degradation. On the contrary, at acidic pH, reaction kinetic modelling demonstrated that ClO• radical occurs at high concentrations in the order of 10-10 M, being therefore the main oxidant, followed by other chlorine radicals. It is noteworthy that at alkaline pH the presence of typical inorganic ions such as carbonate had little impact on ACTP degradation, contrary to the observed reduction of degradation rates at acidic pH. The expected detrimental effect of the NOM in AOPs was also evidenced, although the use of chlorine as radical source reduces the relevance of the inner filter effect in comparison to UV/H2O2.
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Affiliation(s)
- Inmaculada Velo-Gala
- Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003, Girona, Spain; University of Jaén. Department of Inorganic and Organic Chemistry, Faculty of Science, University of Jaén, 23071, Jaén, Spain.
| | - María J Farré
- Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003, Girona, Spain; University of Girona, Spain
| | - Jelena Radjenovic
- Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003, Girona, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluís Companys 23, 08010, Barcelona, Spain
| | - Wolfgang Gernjak
- Catalan Institute for Water Research (ICRA), Emili Grahit 101, 17003, Girona, Spain; Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluís Companys 23, 08010, Barcelona, Spain
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Larbi Djaballah M, Belghit A, Dehane A, Merouani S, Hamdaoui O, Ashokkumar M. Radicals (●OH, Cl●, ClO● and Cl2●–) concentration profiles in the intensified degradation of reactive green 12 by UV/chlorine process: Chemical kinetic analysis using a validated model. J Photochem Photobiol A Chem 2023. [DOI: 10.1016/j.jphotochem.2023.114557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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40
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Zhang H, Li Z, Zhou X, Lu X, Gu H, Ma J. Insight into the performance of UV/chlorine/TiO 2 on carbamazepine degradation: The crucial role of chlorine oxide radical (ClO •). THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 853:158345. [PMID: 36037890 DOI: 10.1016/j.scitotenv.2022.158345] [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: 07/12/2022] [Revised: 08/23/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
The UV/chlorine (UC) system is a homogeneous advanced oxidation process with increasing attention in water decontamination. The addition of TiO2 is a newly found strategy to enhance the generation of hydroxyl radical (HO•) and chlorine radical (Cl•) in the UC system. However, the crucial role of chlorine oxide radical (ClO•, generated by the reactions of HO• and Cl• with chlorine) on pollutant degradation, has not been noticed in UV/chlorine/TiO2 (UCT), the heterogeneous photocatalytic system for chlorine activation. Herein, the role of ClO• in UCT was clarified through quenching experiments combined with model simulations during carbamazepine degradation. Tert-butyl alcohol completely inhibited while bicarbonate only partly suppressed carbamazepine degradation in UCT, indicating the important role of ClO•. The second-order reaction rate constant between ClO• and carbamazepine (kClO•,carbamazepine) was fitted to be (1.21 ± 0.08) × 107 M-1 s-1 by the kinetic model, which avoided the influence of carbonate radical (CO3•-), whose contribution couldn't be excluded during kClO•,carbamazepine determination in commonly used competitive kinetic methods with bicarbonate. With the obtained kClO•,carbamazepine, model simulation suggested that ClO• contributed about 50 % to carbamazepine degradation in UCT, and its concentration was less affected under varied conditions (solution pH, chlorine, bicarbonate, and chloride concentration) to keep an efficient carbamazepine degradation. On the contrary, pollutant degradation dominated by HO• in UCT was largely inhibited with the increase of pH, chlorine, and bicarbonate concentration. In addition to the promotion of degradation efficiency, less disinfection byproducts and lower energy requirement were found in UCT compared with UC. Furthermore, UCT could maintain satisfactory degradation efficiency and energy saving in ground water and surface water samples. Results of this study unraveled the crucial role of ClO• for pollutant degradation in UCT, and showed bright prospects and great potentials of the system in water treatment.
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Affiliation(s)
- Haochen Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Zhuoyu Li
- State Key Laboratory of Heavy Oil Processing, State Key Laboratory of Petroleum Pollution Control, China University of Petroleum-Beijing, Beijing 102249, China
| | - Xiaoqun Zhou
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xiaohui Lu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Haiteng Gu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China.
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Wu L, Patton SD, Liu H. Mechanisms of oxidative removal of 1,4-dioxane via free chlorine rapidly mixing into monochloramine: Implications on water treatment and reuse. JOURNAL OF HAZARDOUS MATERIALS 2022; 440:129760. [PMID: 35969953 DOI: 10.1016/j.jhazmat.2022.129760] [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: 05/10/2022] [Revised: 08/04/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Free chlorine (HOCl) and monochloramine (NH2Cl) are two of the most commonly used water disinfectants in water treatment; however, the capability of rapid mixing of HOCl into NH2Cl to induce oxidative reactions for efficient removal of contaminants remains largely unknown. In this study, 1,4-dioxane (1,4-D) removal was quantified during the rapid mixing of HOCl into NH2Cl, to evaluate the effects of solution pH and HOCl-to-NH2Cl ratio, and to identify mechanisms by which reactive species are generated in the system. Results showed that the highest 1,4-D removal was observed at the near-neutral pH of 6 with the HOCl-to-NH2Cl molar ratio of 1. Hydroxyl radical (HO•) contributed to 60-70 % of 1,4-D degradation and its generation was initiated by the hydrolytic decay of NH2Cl and NHCl2 upon HOCl addition to NH2Cl with rapid mixing, and subsequent transformation of peroxynitrite (ONOO-) and peroxynitrous acid (ONOOH). The results also confirmed that the presence of dissolved oxygen was required to form ONOO-/ONOOH, and ONOO- was a crucial precursor for reactive radical generation. These findings provide insight into the reaction mechanism associated with the system of rapidly mixed HOCl into NH2Cl with the potential optimization and application for efficient trace organics removal in water treatment and reuse.
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Affiliation(s)
- Liang Wu
- Environmental Toxicology Program, University of California, Riverside, CA 92521, USA; Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA
| | - Samuel D Patton
- Environmental Toxicology Program, University of California, Riverside, CA 92521, USA; Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA
| | - Haizhou Liu
- Environmental Toxicology Program, University of California, Riverside, CA 92521, USA; Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA.
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42
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Zhao J, Peng J, Shang C, Yin R. Revisiting the protocol for determining submicromolar concentrations of ozone in the water treated by advanced oxidation processes. CHEMOSPHERE 2022; 303:135117. [PMID: 35636598 DOI: 10.1016/j.chemosphere.2022.135117] [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: 04/13/2022] [Revised: 05/17/2022] [Accepted: 05/23/2022] [Indexed: 06/15/2023]
Abstract
Ozone is formed at submicromolar concentrations from photolysis of many oxyanions and oxidants in water and contributes importantly to the degradation of emerging contaminants and inactivation of pathogenic microorganisms in the natural and engineered aquatic systems. In this study, we identified and discussed the critical limitations of the commonly-used protocols using cinnamic acid (CNA) as a probe compound to determine the submicromolar-level ozone and proposed a modified protocol that overcomes those limitations. Our experimental investigation demonstrated that the radicals (e.g., HO•) formed from photolysis of oxyanions and oxidants, other than ozone, could also oxidize CNA and form benzaldehyde, resulting in the overestimation of ozone concentrations by using the commonly-used protocols. Moreover, the benzaldehyde formed from ozone-CNA reactions could be degraded by the radicals, leading to the underestimation of ozone concentrations by using the commonly-used protocols. A new protocol with high accuracy and precision was proposed and the rationales for each operational step of the new protocol were explained in detail and supported with justifications. The new protocol was compared with two commonly-used protocols in determining the concentration of ozone in the same water sample treated by the UV/chlorine process at three different UV wavelengths. The wavelength-dependent overestimation/underestimation of the ozone concentrations by using the two commonly-used protocols was well demonstrated and explained by the overlooked interferences of radicals in the protocols.
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Affiliation(s)
- Jing Zhao
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Jiadong Peng
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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43
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Yang X, Rosario-Ortiz FL, Lei Y, Pan Y, Lei X, Westerhoff P. Multiple Roles of Dissolved Organic Matter in Advanced Oxidation Processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11111-11131. [PMID: 35797184 DOI: 10.1021/acs.est.2c01017] [Citation(s) in RCA: 89] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Advanced oxidation processes (AOPs) can degrade a wide range of trace organic contaminants (TrOCs) to improve the quality of potable water or discharged wastewater effluents. Their effectiveness is impacted, however, by the dissolved organic matter (DOM) that is ubiquitous in all water sources. During the application of an AOP, DOM can scavenge radicals and/or block light penetration, therefore impacting their effectiveness toward contaminant transformation. The multiple ways in which different types or sources of DOM can impact oxidative water purification processes are critically reviewed. DOM can inhibit the degradation of TrOCs, but it can also enhance the formation and reactivity of useful radicals for contaminants elimination and alter the transformation pathways of contaminants. An in-depth analysis highlights the inhibitory effect of DOM on the degradation efficiency of TrOCs based on DOM's structure and optical properties and its reactivity toward oxidants as well as the synergistic contribution of DOM to the transformation of TrOCs from the analysis of DOM's redox properties and DOM's transient intermediates. AOPs can alter DOM structure properties as well as and influence types, mechanisms, and extent of oxidation byproducts formation. Research needs are proposed to advance practical understanding of how DOM can be exploited to improve oxidative water purification.
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Affiliation(s)
- 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
| | - Fernando L Rosario-Ortiz
- Department of Civil, Environmental and Architectural Engineering, University of Colorado, Boulder, Colorado 80309, United States
| | - Yu Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Yanheng Pan
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Xin Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Paul Westerhoff
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona 85287-3005, United States
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Xu MY, Lin YL, Zhang TY, Hu CY, Tang YL, Deng J, Xu B. Chlorine dioxide-based oxidation processes for water purification:A review. JOURNAL OF HAZARDOUS MATERIALS 2022; 436:129195. [PMID: 35739725 DOI: 10.1016/j.jhazmat.2022.129195] [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: 03/17/2022] [Revised: 05/14/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
Chlorine dioxide (ClO2) has emerged as a broad-spectrum, safe, and effective disinfectant due to its high oxidation efficiency and reduced formation of organochlorinated by-products during application. This article provides an updated overview of ClO2-based oxidation processes used in water treatment. A systematic review of scientific information and experimental data on ClO2-based water purification procedures is presented. Concerning ClO2-based oxidation derivative problems, the pros and cons of ClO2-based combined processes are assessed and disinfection by-product (DBP) control approaches are proposed. The kinetic and mechanistic data on ClO2 reactivity towards micropollutants are discussed. ClO2 selectively reacts with electron-rich moieties (anilines, phenols, olefins, and amines) and eliminates certain inorganic ions and microorganisms with high efficiency. The formation of chlorite and chlorate during the oxidation process is a crucial concern when utilizing ClO2. Future applications include the combination of ClO2 with ferrous ions, activated carbon, ozone, UV, visible light, or persulfate processes. The combined process can reduce by-product generation while still ensuring ClO2 sterilization and disinfection. Overall, this research could provide useful information and new insights into the application of ClO2-based technologies.
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Affiliation(s)
- Meng-Yuan Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Yi-Li Lin
- Department of Safety, Health and Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 824, Taiwan, ROC
| | - Tian-Yang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Chen-Yan Hu
- College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, PR China
| | - Yu-Lin Tang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Jing Deng
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, PR China
| | - Bin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Luo C, Li M, Cheng X, Wu D, Tan F, Li Z, Chen Y, Yu F, Ma Q. Degradation of iopamidol by UV 365/NaClO: Roles of reactive species, degradation mechanism, and toxicology. WATER RESEARCH 2022; 222:118840. [PMID: 35858527 DOI: 10.1016/j.watres.2022.118840] [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: 03/29/2022] [Revised: 07/06/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
The degradation of iopamidol (IPM) was investigated using a UV365/NaClO system. The reactive species (HO·, ClO·, ozone, Cl·, and Cl2-·) in the system were identified, and the changing trends of the percentage contributions of these reactive species to IPM removal under various conditions were systematically evaluated. The results showed that ClO· and HO· played the most significant roles in the apparent pseudo-first-order rate constants of IPM degradation (kobs, min-1) in the control experiment, and their percentage contributions to kobs were 41.31% and 34.45%, respectively. In addition, Cl· and Cl2-· together contributed 22% to the kobs. Furthermore, the contribution of ozone to the IPM removal could be neglected. The concentrations of these species increased significantly when the concentration of NaClO was increased from 50 µM to 200 µM, while the percentage contribution of ClO· to kobs was greatly increased. The concentrations and percentage contributions of HO· and ClO· decreased significantly as the solution pH increased from 5 to 9, with Cl2-· playing a greater role in the degradation of IPM under alkaline conditions. While Cl- or HCO3-/CO32- significantly promoted the generation of Cl2-· or CO3-·, neither had an obvious effect on kobs, suggesting that Cl2-· and CO3-· should have a certain reactivity with IPM. Compared with that of Cl2-·, the percentage contribution of ClO· and Cl· to kobs was more likely to be inhibited by NOM. In addition, the organic and inorganic oxidation products of IPM were detected. The oxidation mechanisms of IPM degradation in the UV365/NaClO system, such as the H-extraction reaction, deiodination, substitution reaction, amide hydrolysis, and amine oxidation, were proposed according to the obtained 15 organic products. No effect on acute toxicity towards Vibrio fischeri and Photobacterium phosphoreum was detected during the oxidation of IPM by the UV365/NaClO system. Furthermore, the engineering feasibility of the oxidation system was demonstrated, by the effective degradation of IPM in actual water. However, HOI rapidly accumulated during the removal of IPM in the UV365/NaClO system, which poses certain environmental risks and will needs to be investigated.
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Affiliation(s)
- Congwei Luo
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China; Resources and Environment Innovation Institute, Shandong Jianzhu University, Jinan, 250101, P. R. China
| | - Ming'an Li
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China
| | - Xiaoxiang Cheng
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China.
| | - Daoji Wu
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China; Resources and Environment Innovation Institute, Shandong Jianzhu University, Jinan, 250101, P. R. China
| | - Fengxun Tan
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China
| | - Zhiquan Li
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China
| | - Yongkai Chen
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China
| | - Fan Yu
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, Jinan, 250101, P. R. China
| | - Qiao Ma
- National Engineering Lab of Coal-Fired Pollution Emission Reduction, School of Energy and Power Engineering, Shandong University, Jinan 250061, P. R. China
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White AM, Nault ME, McMahon KD, Remucal CK. Synthesizing Laboratory and Field Experiments to Quantify Dominant Transformation Mechanisms of 2,4-Dichlorophenoxyacetic Acid (2,4-D) in Aquatic Environments. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:10838-10848. [PMID: 35856571 DOI: 10.1021/acs.est.2c03132] [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] [Indexed: 06/15/2023]
Abstract
Laboratory studies used to assess the environmental fate of organic chemicals such as pesticides fail to replicate environmental conditions, resulting in large errors in predicted transformation rates. We combine laboratory and field data to identify the dominant loss processes of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) in lakes for the first time. Microbial and photochemical degradation are individually assessed using laboratory-based microcosms and irradiation studies, respectively. Field campaigns are conducted in six lakes to quantify 2,4-D loss following large-scale herbicide treatments. Irradiation studies show that 2,4-D undergoes direct photodegradation, but modeling efforts demonstrated that this process is negligible under environmental conditions. Microcosms constructed using field inocula show that sediment microbial communities are responsible for degradation of 2,4-D in lakes. Attempts to quantify transformation products are unsuccessful in both laboratory and field studies, suggesting that their persistence is not a major concern. The synthesis of laboratory and field experiments is used to demonstrate best practices in designing laboratory persistence studies and in using those results to mechanistically predict contaminant fate in complex aquatic environments.
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Affiliation(s)
- Amber M White
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Michelle E Nault
- Wisconsin Department of Natural Resources Madison, Bureau of Water Quality, Madison, Wisconsin 53707, United States
| | - Katherine D McMahon
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department of Bacteriology, University of Wisconsin-Madison Madison, Wisconsin 53706, United States
| | - Christina K Remucal
- Environmental Chemistry and Technology Program, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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Wojnárovits L, Wang J, Chu L, Takács E. Rate constants of chlorine atom reactions with organic molecules in aqueous solutions, an overview. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:55492-55513. [PMID: 35688978 PMCID: PMC9374632 DOI: 10.1007/s11356-022-20807-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 05/10/2022] [Indexed: 05/15/2023]
Abstract
Rate constants of chlorine atom (Cl•) reactions (kCl•) determined using a large variation of experimental methods, including transient measurements, steady-state and computation techniques, were collected from the literature and were discussed together with the reaction mechanisms. The kCl• values are generally in the 108-109 mol-1 dm3 s-1 range when the basic reaction between the Cl• and the target molecule is H-atom abstraction. When Cl• addition to double bonds dominates the interaction, the kCl• values are in the 1 × 109-2 × 1010 mol-1 dm3 s-1 range. In the kCl• = 1 × 1010-4 × 1010 mol-1 dm3 s-1 range, single-electron-transfer reactions may also contribute to the mechanism. The Cl• reactions with organic molecules in many respects are similar to those of •OH, albeit Cl• seems to be less selective as •OH. However, there is an important difference, as opposed to Cl• in the case of •OH single-electron-transfer reactions have minor importance. The uncertainty of Cl• rate constant determinations is much higher than those of •OH. Since Cl• reactions play very important role in the emerging UV/chlorine water purification technology, some standardization of the rate constant measuring techniques and more kCl• measurements are recommended.
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Affiliation(s)
- László Wojnárovits
- Institute for Energy Security and Environmental Safety, Centre for Energy Research, Radiation Chemistry Department, ELKH, Budapest, Hungary
| | - Jianlong Wang
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Libing Chu
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing, 100084, People's Republic of China
| | - Erzsébet Takács
- Institute for Energy Security and Environmental Safety, Centre for Energy Research, Radiation Chemistry Department, ELKH, Budapest, Hungary.
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Activation of Bisulfite with Pyrophosphate-Complexed Mn(III) for Fast Oxidation of Organic Pollutants. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19159437. [PMID: 35954793 PMCID: PMC9368537 DOI: 10.3390/ijerph19159437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/24/2022] [Accepted: 07/28/2022] [Indexed: 12/04/2022]
Abstract
Aqueous complexes of Mn(III) ion with ligands exist in various aquatic systems and many stages of water treatment works, while HSO3− is a common reductant in water treatment. This study discloses that their encounter results in a process that oxidizes organic contaminants rapidly. Pyrophosphate (PP, a nonredox active ligand) was used to prepare the Mn(III) solution. An approximate 71% removal of carbamazepine (CBZ) was achieved by the Mn(III)/HSO3− process at pH 7.0 within 20 s, while negligible CBZ was degraded by Mn(III) or HSO3− alone. The reactive species responsible for pollutant abatement in the Mn(III)/HSO3− process were SO4•− and HO•. The treatment efficiency of the Mn(III)/HSO3− process is highly related to the dosage of HSO3− because HSO3− acted as both the radical scavenger and precursor. The reaction of Mn(III) with HSO3− follows second-order reaction kinetics and the second-order rate constants ranged from 7.5 × 103 to 17 M−1 s−1 under the reaction conditions of this study, suggesting that the Mn(III)/HSO3− process is an effective process for producing SO4•−. The pH and PP:Mn(III) ratio affect the reactivity of Mn(III) towards HSO3−. The water background constituents, such as Cl− and dissolved organic matter, induce considerable loss of the treatment efficiency in different ways.
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Hoang NT, Nguyen VT, Minh Tuan ND, Manh TD, Le PC, Van Tac D, Mwazighe FM. Degradation of dyes by UV/Persulfate and comparison with other UV-based advanced oxidation processes: Kinetics and role of radicals. CHEMOSPHERE 2022; 298:134197. [PMID: 35276111 DOI: 10.1016/j.chemosphere.2022.134197] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 02/11/2022] [Accepted: 03/01/2022] [Indexed: 06/14/2023]
Abstract
This study investigated the degradation of methylene blue (MeB), methyl orange (MeO), and rhodamin B (RhB) by the UV/Persulfate (UV/PS) process. The dye degradation in the investigated UV-based Advanced Oxidation Processes (UV/AOPs) followed the first-order kinetic model. The second-order rate constant of the dyes with •OH, SO4•-, and CO3•- were calculated and found to be: k•OH,MeB = 5.6 × 109 M-1 s-1, [Formula: see text] = 3.3 × 109 M-1 s-1, [Formula: see text] = 6.9 × 107 M-1 s-1; k•OH,MeO = 3.2 × 109 M-1 s-1, [Formula: see text] = 13 × 109 M-1 s-1, [Formula: see text] = 4.4 × 106 M-1 s-1; k•OH,RhB = 14.8 × 109 M-1 s-1, [Formula: see text] = 5 × 109 M-1 s-1, [Formula: see text] = 1 × 107 M-1 s-1. The steady-state concentrations of •OH and SO4•- (including other reactive species) were determined using both chemical probes and modeling methods (Kintecus® V6.8). In the UV/PS, the dye degradation depends on the pH of the solution with the order: kdye (at pH of 7) > kdye (in acidic conditions) > kdye (in alkaline conditions). The presence of water matrices had different impacts on dye degradation: 1) The HCO3- and Cl- promoted the degradation efficiency of one dye, but also inhibited the degradation of other dyes; 2) Humic acid (HA) inhibited dye degradation as it scavenged both •OH and SO4•-. The degradation of the dyes by UV/PS was also compared with the UV/Chlorine (UV/HOCl) and UV/H2O2 and it was established that: 1) In UV/PS and UV/HOCl, SO4•- and RCS contributed to dye degradation more than •OH, while •OH played a major role in dye degradation by UV/H2O2; 2) The calculated toxicity in UV/PS was the lowest probably due to the low toxicity of by-products; 3) For MeO and RhB, the UV/PS process is more beneficial for the total organic carbon (TOC) removal compared to that of the UV/HOCl and UV/H2O2 processes; 4) The UV/PS showed lower cost than the UV/HOCl and UV/H2O2 systems for MeO, and RhB degradation but higher cost for MeB removal.
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Affiliation(s)
- Nguyen Tien Hoang
- The University of Danang, University of Science and Education, Da Nang, 550 000, Viet Nam.
| | - Vo Thang Nguyen
- The University of Danang, University of Science and Education, Da Nang, 550 000, Viet Nam
| | - Nguyen Dinh Minh Tuan
- The University of Danang, University of Science and Technology, Da Nang, 550 000, Viet Nam
| | - Tran Duc Manh
- The University of Danang, University of Science and Education, Da Nang, 550 000, Viet Nam
| | - Phuoc-Cuong Le
- The University of Danang, University of Science and Technology, Da Nang, 550 000, Viet Nam
| | - Dinh Van Tac
- The University of Danang, University of Science and Education, Da Nang, 550 000, Viet Nam
| | - Fredrick M Mwazighe
- Department of Chemistry, University of Nairobi, P. O. Box 30197, 00100, Nairobi, Kenya
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Zhao J, Peng J, Yin R, Fan M, Yang X, Shang C. Multi-angle comparison of UV/chlorine, UV/monochloramine, and UV/chlorine dioxide processes for water treatment and reuse. WATER RESEARCH 2022; 217:118414. [PMID: 35429880 DOI: 10.1016/j.watres.2022.118414] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 12/31/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Advanced oxidation processes (AOPs) have been increasingly studied and practiced for micropollutant abatement in drinking water treatment and potable water reuse. This study conducted the multi-angle comparison of the UV/chlorine, UV/monochloramine (UV/NH2Cl), and UV/chlorine dioxide (UV/ClO2) AOPs with respect to reactive species generation, micropollutant degradation, byproduct formation, and toxicity change. The concentrations of radicals (HO·, Cl·, and ClO·) generated in the three AOPs followed the order of UV/chlorine > UV/NH2Cl > UV/ClO2 at an oxidant dose of 70 μM, an irradiation wavelength of 254 nm, and a pH of 7.5. The concentration of ozone generated in the UV/ClO2 AOP was higher than that in the UV/chlorine AOP, while ozone was not generated in the UV/NH2Cl AOP. The effects of pH (pH 6.0, 7.5, and 9.0) and UV wavelength (254 nm, 285 nm, and 300 nm) on the three AOPs were evaluated and compared. Using the radical and ozone concentrations determined in this study, the pseudo-first-order degradation rate constants of 24 micropollutants by the three AOPs were predicted and compared. When the three AOPs were used to treat the water containing the same concentration of natural organic matter, the formation of total organic chlorine (TOCl) and the organic byproduct-associated toxicity followed the same order of UV/chlorine > UV/NH2Cl > UV/ClO2. On the contrary, the inorganic byproduct-associated toxicity followed the order of UV/ClO2 > UV/chlorine > UV/NH2Cl, due to the high concentrations of chlorite and chlorate formed in the UV/ClO2 AOP. Findings in this study offer fundamental information useful for the selection and operation of AOPs for micropollutant abatement in drinking water treatment and potable water reuse.
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Affiliation(s)
- Jing Zhao
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Jiadong Peng
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
| | - Mengge Fan
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Xin Yang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China; Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
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