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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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Du Y, Liu T, Yang LL, Song ZM, Dai X, Wang WL, Lai B, Wu QY. Ferrate(VI) assists in reducing cytotoxicity and genotoxicity to mammalian cells and organic bromine formation in ozonated wastewater. WATER RESEARCH 2024; 253:121353. [PMID: 38401473 DOI: 10.1016/j.watres.2024.121353] [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: 11/25/2023] [Revised: 02/04/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
Ozonation of wastewater containing bromide (Br-) forms highly toxic organic bromine. The effectiveness of ozonation in mitigating wastewater toxicity is minimal. Simultaneous application of ozone (O3) (5 mg/L) and ferrate(VI) (Fe(VI)) (10 mg-Fe/L) reduced cytotoxicity and genotoxicity towards mammalian cells by 39.8% and 71.1% (pH 7.0), respectively, when the wastewater has low levels of Br-. This enhanced reduction in toxicity can be attributed to increased production of reactive iron species Fe(IV)/Fe(V) and reactive oxygen species (•OH) that possess higher oxidizing ability. When wastewater contains 2 mg/L Br-, ozonation increased cytotoxicity and genotoxicity by 168%-180% and 150%-155%, respectively, primarily due to the formation of organic bromine. However, O3/Fe(VI) significantly (p < 0.05) suppressed both total organic bromine (TOBr), BrO3-, as well as their associated toxicity. Electron donating capacity (EDC) measurement and precursor inference using Orbitrap ultra-high resolution mass spectrometry found that Fe(IV)/Fe(V) and •OH enhanced EDC removal from precursors present in wastewater, inhibiting electrophilic substitution and electrophilic addition reactions that lead to organic bromine formation. Additionally, HOBr quenched by self-decomposition-produced H2O2 from Fe(VI) also inhibits TOBr formation along with its associated toxicity. The adsorption of Fe(III) flocs resulting from Fe(VI) decomposition contributes only minimally to reducing toxicity. Compared to ozonation alone, integration of Fe(VI) with O3 offers improved safety for treating wastewater with varying concentrations of Br-.
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Affiliation(s)
- Ye Du
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Tong Liu
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Lu-Lin Yang
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Zhi-Min Song
- Michigan Technological University, 1400 Townsend Drive Houghton, MI 49931, United States
| | - Xin Dai
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Wen-Long Wang
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Bo Lai
- College of Architecture and Environment, Sichuan University, Chengdu 610000, China
| | - Qian-Yuan Wu
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
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Yin R, Heuzard A, Li T, Ruan X, Lu S, Shang C. Advanced oxidation of recalcitrant chromophores in full-scale MBR effluent for non-potable reuse of leachate co-treated municipal wastewater. CHEMOSPHERE 2024; 351:141228. [PMID: 38237782 DOI: 10.1016/j.chemosphere.2024.141228] [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: 11/30/2023] [Revised: 01/08/2024] [Accepted: 01/13/2024] [Indexed: 01/22/2024]
Abstract
Wastewater non-potable reuse involves further processing of secondary effluent to a quality level acceptable for reuse and is a promising solution to combating water scarcity. Recalcitrant chromophores in landfill leachate challenge the water quality for non-potable reuse when leachate is co-treated with municipal wastewater. In this study, we first use multivariate statistical analysis to reveal that leachate is an important source (with a Pearson's coefficient of 0.82) of recalcitrant chromophores in the full-scale membrane bioreactor (MBR) effluent. We then evaluate the removal efficacies of chromophores by chlorination, breakpoint chlorination, and the chlorination-UV/chlorine advanced oxidation treatment. Conventional chlorination and breakpoint chlorination only partially remove chromophores, leaving a colour level exceeding the standards for non-potable reuse (>20 Hazen units). We demonstrate that pre-chlorination (with an initial chlorine dosing of 20 mg/L as Cl2) followed by UV radiation (with a UV fluence of 500 mJ/cm2) effectively degraded recalcitrant chromophores (>90%). By quantifying the electron donating capacity (EDC) and radical scavenging capacity (RSC) of the reclaimed water, we demonstrate that pre-chlorination reduces EDC and RSC by up to 64%, increases UV transmittance by 32%, and increases radical yields from UV photolysis of chlorine by 1.7-2.2 times. The findings advance fundamental understanding of the alteration of dissolved coloured substances by (photo)chlorination treatment and provide implications for applying advanced oxidation processes in treating wastewater effluents towards sustainable non-potable reuse.
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Affiliation(s)
- Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
| | - Arnaud Heuzard
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Tao Li
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; China State Construction Engineering (Hong Kong) Limited, Wan Chai, Hong Kong
| | - Xinyi Ruan
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Senhao Lu
- 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 Centre for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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Swenson JT, Ginder-Vogel M, Remucal CK. Influence of Divalent Cation Inhibition and Dissolved Organic Matter Enhancement on Phenol Oxidation Kinetics by Manganese Oxides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:2479-2489. [PMID: 38265036 DOI: 10.1021/acs.est.3c08273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
Manganese oxides can oxidize organic compounds, such as phenols, and may potentially be used in passive water treatment applications. However, the impact of common water constituents, including cations and dissolved organic matter (DOM), on this reaction is poorly understood. For example, the presence of DOM can increase or decrease phenol oxidation rates with manganese oxides. Furthermore, the interactions of DOM and cations and their impact on the phenol oxidation rates have not been examined. Therefore, we investigated the oxidation kinetics of six phenolic contaminants with acid birnessite in ten whole water samples. The oxidation rate constants of 4-chlorophenol, 4-tert-octylphenol, 4-bromophenol, and phenol consistently decreased in all waters relative to buffered ultrapure water, whereas the oxidation rate of bisphenol A and triclosan increased by up to 260% in some waters. Linear regression analyses and targeted experiments demonstrated that the inhibition of phenol oxidation is largely determined by cations. Furthermore, quencher experiments indicated that radical-mediated interactions from oxidized DOM contributed to enhanced oxidation of bisphenol A. The variable changes between compounds and water samples demonstrate the challenge of accurately predicting contaminant transformation rates in environmentally relevant systems based on experiments conducted in the absence of natural water constituents.
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Affiliation(s)
- Jenna T Swenson
- Environmental Chemistry and Technology, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Matthew Ginder-Vogel
- Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Christina K Remucal
- Environmental Chemistry and Technology, 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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Lei X, Lei Y, Fu Q, Fu H, Guan J, Yang X. One-electron oxidant-induced transformation of dissolved organic matter: Optical and antioxidation properties and molecules. WATER RESEARCH 2024; 249:121011. [PMID: 38101043 DOI: 10.1016/j.watres.2023.121011] [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] [Received: 08/31/2023] [Revised: 11/22/2023] [Accepted: 12/10/2023] [Indexed: 12/17/2023]
Abstract
Dissolved organic matter (DOM) is a major sink of radicals in advanced oxidation processes (AOPs) and the radical-induced DOM transformation influences the subsequent water treatment processes or receiving waters. In this study, we quantified and compared DOM transformation by tracking the changes of dissolved organic carbon (DOC), UVA254, and electron donating capacity (EDC) as functions of four one-electron oxidants (SO4•-, Cl2•-, Br2•-, and CO3•-) exposures as well as the changes of functional groups and molecule distribution. SO4•- had the highest DOC reduction while Cl2•- had the highest EDC reduction, which could be due to their preferential reaction pathways of decarboxylation and converting phenols to quinones, respectively. Br2•- and CO3•- induced less changes in DOC, UVA254, and EDC than SO4•- and Cl2•-. Additionally, DOM enriched with high aromatic contents tended to have higher DOC, UVA254, and EDC reductions. Decreases in hydroxyl and carboxyl groups and increases in carbonyl groups were observed in these four types of radicals treated DOM using Fourier transform infrared spectroscopy. High resolution mass spectrometry using FTICR-MS showed that one-electron oxidants preferred to attack unsaturated carbon skeletons and transformed into molecules featuring high saturation and low aromaticity. Moreover, SO4•- was inclined to decrease oxidation state of carbon and O/C of DOM due to its strong decarboxylation capacity. This study highlights the distinct DOM transformation by four one-electron oxidants and provides comprehensive insights into the reactions of one-electron oxidants with DOM.
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Affiliation(s)
- 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, PR China; Yunnan Provincial Key Laboratory of Soil Carbon Sequestration and Pollution Control, Faculty of Environmental Science & Engineering, Kunming University of Science & Technology, Kunming 650500, PR China
| | - Yu Lei
- Key Laboratory of Photochemistry, Institute of Chemistry Chinese Academy of Sciences, Beijing National Laboratory for Molecular Sciences, Beijing 100190, PR China
| | - Qinglong Fu
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, PR China
| | - Hengyi Fu
- The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, School of Environment and Energy, South China University of Technology, Guangzhou 510006, PR China
| | - Jingmeng Guan
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR 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, PR China.
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Pan Y, Garg S, Fu QL, Peng J, Yang X, Waite TD. Copper Safeguards Dissolved Organic Matter from Sunlight-Driven Photooxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21178-21189. [PMID: 38064756 DOI: 10.1021/acs.est.3c07549] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Sunlight plays a crucial role in the transformation of dissolved organic matter (DOM) and the associated carbon cycle in aquatic environments. This study demonstrates that the presence of nanomolar concentrations of copper (Cu) significantly decreases the rate of photobleaching and the rate of loss of electron-donating moieties of three selected types of DOM (including both terrestrial and microbially derived DOM) under simulated sunlight irradiation. Employing Fourier transform ion cyclotron resonance mass spectrometry, we further confirm that Cu selectively inhibits the photooxidation of lignin- and tannin-like phenolic moieties present within the DOM, in agreement with the reported inhibitory impact of Cu on the photooxidation of phenolic compounds. On the basis of the inhibitory impact of Cu on the DOM photobleaching rate, we calculate the contribution of phenolic moieties to DOM photobleaching to be at least 29-55% in the wavelength range of 220-460 nm. The inhibition of loss of electrons from DOM during irradiation in the presence of Cu is also explained quantitatively by developing a mathematical model describing hydrogen peroxide (a proxy measure of loss of electrons from DOM) formation on DOM irradiation in the absence and presence of Cu. Overall, this study advances our understanding of DOM transformation in natural sunlit waters.
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Affiliation(s)
- Yanheng Pan
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Shikha Garg
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Qing-Long Fu
- School of Environmental Studies, China University of Geosciences, Wuhan 430078, China
| | - Jianglin Peng
- 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 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
| | - T David Waite
- School of Civil and Environmental Engineering, The University of New South Wales, Sydney, New South Wales 2052, Australia
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Zou J, Liu Y, Han Q, Tian Y, Shen F, Kang L, Feng L, Ma J, Zhang L, Du Z. Importance of Chain Length in Propagation Reaction on •OH Formation during Ozonation of Wastewater Effluent. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18811-18824. [PMID: 37428486 DOI: 10.1021/acs.est.3c00827] [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: 07/11/2023]
Abstract
During the ozonation of wastewater, hydroxyl radicals (•OH) induced by the reactions of ozone (O3) with effluent organic matters (EfOMs) play an essential role in degrading ozone-refractory micropollutants. The •OH yield provides the absolute •OH formation during ozonation. However, the conventional "tert-Butanol (t-BuOH) assay" cannot accurately determine the •OH yield since the propagation reactions are inhibited, and there have been few studies on •OH production induced by EfOM fractions during ozonation. Alternatively, a "competitive method", which added trace amounts of the •OH probe compound to compete with the water matrix and took initiation reactions and propagation reactions into account, was used to determine the actual •OH yields (Φ) compared with that obtained by the "t-BuOH assay" (φ). The Φ were significantly higher than φ, indicating that the propagation reactions played important roles in •OH formation. The chain propagation reactions facilitation of EfOMs and fractions can be expressed by the chain length (n). The study found significant differences in Φ for EfOMs and fractions, precisely because they have different n. The actual •OH yield can be calculated by n and φ as Φ = φ (1 + n)/(nφ + 1), which can be used to accurately predict the removal of micropollutants during ozonation of wastewater.
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Affiliation(s)
- Jinru Zou
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Yongze Liu
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Qi Han
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Yajun Tian
- College of Environment, Zhejiang University of Technology, Chaowang Road 18, Hangzhou 310014, China
| | - Fangfang Shen
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Longfei Kang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Li Feng
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Liqiu Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Ziwen Du
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
- Engineering Research Center for Water Pollution Source Control and Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
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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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Mensah AT, Xiang Y, Berne F, Soreau S, Gallard H. Reactions of Monobromamine and Dibromamine with Phenolic Compounds and Organic Matter: Kinetics and Formation of Bromophenols and Bromoform. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18981-18990. [PMID: 37226837 DOI: 10.1021/acs.est.3c00935] [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: 05/26/2023]
Abstract
Monobromamine (NH2Br) and dibromamine (NHBr2) produced from reactions of hypobromous acid (HOBr) with ammonia can react with phenolic structures of natural organic matter (NOM) to produce disinfection byproducts such as bromoform (CHBr3). The reactivity of NH2Br was controlled by the reaction of the bromoammonium ion (NH3Br+) with phenolate species, with specific rate constants ranging from 6.32 × 102 for 2,4,6-tribromophenol to 1.22 × 108 M-1 s-1 for phenol. Reactions of NHBr2 with phenol and bromophenols were negligible compared to its self-decomposition; rate constants could be determined only with resorcinol for pH > 7. At pH 8.1-8.2, no formation of CHBr3 was observed from the reaction of NH2Br with phenol while the reaction of NH2Br with resorcinol produced a significant concentration of CHBr3. In contrast to NH2Br, a significant amount of CHBr3 produced with an excess of NHBr2 over phenol was explained by the reactions of HOBr produced from NHBr2 decomposition. A comprehensive kinetic model including the formation and decomposition of bromamines and the reactivity of HOBr and NH2Br with phenolic compounds was developed at pH 8.0-8.3. Furthermore, the kinetic model was used to evaluate the significance of the NH2Br and NHBr2 reactions with the phenolic structures of two NOM isolates.
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Affiliation(s)
- Anette T Mensah
- Institut de Chimie des Milieux et des Matériaux de Poitiers IC2MP UMR 7285 CNRS Université de Poitiers, ENSI Poitiers, 1 rue Marcel Doré TSA 41105, 86 073 Cedex 9, Poitiers, France
| | - Yingying Xiang
- Institut de Chimie des Milieux et des Matériaux de Poitiers IC2MP UMR 7285 CNRS Université de Poitiers, ENSI Poitiers, 1 rue Marcel Doré TSA 41105, 86 073 Cedex 9, Poitiers, France
| | - Florence Berne
- Institut de Chimie des Milieux et des Matériaux de Poitiers IC2MP UMR 7285 CNRS Université de Poitiers, ENSI Poitiers, 1 rue Marcel Doré TSA 41105, 86 073 Cedex 9, Poitiers, France
| | - Sylvie Soreau
- EDF - Recherche et Développement, Laboratoire National d'Hydraulique et Environnement (LNHE), 6 quai Watier, 78401 Chatou Cedex, France
| | - Hervé Gallard
- Institut de Chimie des Milieux et des Matériaux de Poitiers IC2MP UMR 7285 CNRS Université de Poitiers, ENSI Poitiers, 1 rue Marcel Doré TSA 41105, 86 073 Cedex 9, Poitiers, France
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10
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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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11
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Shi J, Wang Z, Peng Y, Fan Z, Zhang Z, Wang X, Zhu K, Shang J, Wang J. Effects of Microplastics on Soil Carbon Mineralization: The Crucial Role of Oxygen Dynamics and Electron Transfer. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:13588-13600. [PMID: 37647508 DOI: 10.1021/acs.est.3c02133] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Although our understanding of the effects of microplastics on the dynamics of soil organic matter (SOM) has considerably advanced in recent years, the fundamental mechanisms remain unclear. In this study, we examine the effects of polyethylene and poly(lactic acid) microplastics on SOM processes via mineralization incubation. Accordingly, we evaluated the changes in carbon dioxide (CO2) and methane (CH4) production. An O2 planar optical sensor was used to detect the temporal behavior of dissolved O2 during incubation to determine the microscale oxygen heterogeneity caused by microplastics. Additionally, the changes in soil dissolved organic matter (DOM) were evaluated using a combination of spectroscopic approaches and ultrahigh-resolution mass spectrometry. Microplastics increased cumulative CO2 emissions by 160-613%, whereas CH4 emissions dropped by 45-503%, which may be attributed to the oxygenated porous habitats surrounding microplastics. Conventional and biodegradable microplastics changed the quantities of soil dissolved organic carbon. In the microplastic treatments, DOM with more polar groups was detected, suggesting a higher level of electron transport. In addition, there was a positive correlation between the carbon concentration, electron-donating ability, and CO2 emission. These findings suggest that microplastics may facilitate the mineralization of SOM by modifying O2 microenvironments, DOM concentration, and DOM electron transport capability. Accordingly, this study provides new insights into the impact of microplastics on soil carbon dynamics.
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Affiliation(s)
- Jia Shi
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Zi Wang
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Yumei Peng
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Zhongmin Fan
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Ziyun Zhang
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Xiang Wang
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Kun Zhu
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Jianying Shang
- Key Laboratory of Arable Land Conservation (North China), College of Land Science and Technology, China Agricultural University, Beijing 100193, People's Republic of China
| | - Jie Wang
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, People's Republic of China
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12
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Guo Y, Yu G, von Gunten U, Wang Y. Evaluation of the role of superoxide radical as chain carrier for the formation of hydroxyl radical during ozonation. WATER RESEARCH 2023; 242:120158. [PMID: 37329717 DOI: 10.1016/j.watres.2023.120158] [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: 01/06/2023] [Revised: 04/26/2023] [Accepted: 05/30/2023] [Indexed: 06/19/2023]
Abstract
Superoxide radicals (O2•-) have been suggested as an important chain carrier in the radical chain reaction that promotes ozone (O3) decomposition to hydroxyl radicals (•OH) during ozonation. However, due to the difficulty in measuring transient O2•- concentrations, this hypothesis has not been verified under realistic ozonation conditions during water treatment. In this study, a probe compound was used in combination with kinetic modeling to evaluate the role of O2•- for O3 decomposition during ozonation of synthetic solutions with model promotors and inhibitors (methanol and acetate or tert-butanol) and natural waters (one groundwater and two surface waters). By measurement of the abatement of spiked tetrachloromethane (as a O2•- probe), the O2•- exposure during ozonation was determined. Based on the measured O2•- exposures, the relative contribution of O2•- to O3 decomposition, in comparison to OH-, •OH, and dissolved organic matter (DOM), was quantitatively evaluated using kinetic modeling. The results show that water compositions (e.g., the concentration of promotors and inhibitors, and the O3 reactivity of DOM) have a considerable effect on the extent of the O2•--promoted radical chain reaction during ozonation. In general, the reaction with O2•- accounted for ∼59‒70% and ∼45‒52% of the overall O3 decomposition during ozonation of the selected synthetic solutions and natural waters, respectively. This confirms that O2•- plays a critical role in promoting O3 decomposition to •OH. Overall, this study provides new insights on the controlling factors for ozone stability during ozonation processes.
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Affiliation(s)
- 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, Beijing 100084 China
| | - Gang Yu
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, Beijing 100084 China
| | - Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - 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, Beijing 100084 China.
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13
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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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14
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Luong XTH, Shen YS, Liang C, Chen YT. Evaluation of various natural weeds and reaction conditions for reductive degradation of 1,3-dinitrobenzene. JOURNAL OF HAZARDOUS MATERIALS 2023; 454:131467. [PMID: 37104957 DOI: 10.1016/j.jhazmat.2023.131467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 04/09/2023] [Accepted: 04/20/2023] [Indexed: 05/19/2023]
Abstract
1,3-Dinitrobenzene (1,3-DNB) is listed by the USEPA as a priority pollutant. 1,3-DNB has two nitro functional groups (-NO2) bound to the benzene ring, with a +III nitrogen oxidation states, and strong electronegativity, and therefore can be reductively degraded by gaining electrons. Weeds that contain a high proportion of polyphenols can supply electrons and act as natural reducing agents. This study investigated the potential of various weeds to reductively remove 1,3-DNB from aqueous phase. The Taguchi L9 Orthogonal experimental design method was used to explore the optimum operational parameters. According to the analyzed characteristics of weeds, including total phenol content, antioxidant capacity, metal chelating capacity, reducing capacity, and environmental adaptability, the weed Sphagneticola trilobata, containing 11.93 mg of gallic acid equivalent per gram of weed (mg-GAE/g-weed), was selected for 1,3-DNB degradation experiments. The results showed that the optimum reaction conditions for the degradation of 1,3-DNB in the aqueous phase using Sphagneticola trilobata were: pH 3, a weed dose of 10 g/L, reaction time of 14 day, and initial 1,3-DNB concentration of 0.5 mM. According to ANOVA analysis, the weed dose was the most significant factor in the experiment, and each 1 mg of 1,3-DNB degraded required 120 mg of dry weeds.
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Affiliation(s)
- Xuyen Thi Hong Luong
- Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Road, Taichung 402, Taiwan
| | - Yu-Shan Shen
- Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Road, Taichung 402, Taiwan
| | - Chenju Liang
- Department of Environmental Engineering, National Chung Hsing University, 145 Xingda Road, Taichung 402, Taiwan.
| | - Yao-Tsung Chen
- Apollo Technology CO., LTD. 6A New Design Building, No. 22, Section 3, Zhongshan N. Rd., Zhongshan Dist., Taipei 104, Taiwan
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15
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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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16
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Ma L, Worland R, Tran T, Anastasio C. Evaluation of Probes to Measure Oxidizing Organic Triplet Excited States in Aerosol Liquid Water. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:6052-6062. [PMID: 37011016 DOI: 10.1021/acs.est.2c09672] [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: 06/19/2023]
Abstract
Oxidizing triplet excited states of organic matter (3C*) drive numerous reactions in fog/cloud drops and aerosol liquid water (ALW). Quantifying oxidizing triplet concentrations in ALW is difficult because 3C* probe loss can be inhibited by the high levels of dissolved organic matter (DOM) and copper in particle water, leading to an underestimate of triplet concentrations. In addition, illuminated ALW contains high concentrations of singlet molecular oxygen (1O2*), which can interfere with 3C* probes. Our overarching goal is to find a triplet probe that has low inhibition by DOM and Cu(II) and low sensitivity to 1O2*. To this end, we tested 12 potential probes from a variety of compound classes. Some probes are strongly inhibited by DOM, while others react rapidly with 1O2*. One of the probe candidates, (phenylthiol)acetic acid (PTA), seems well suited for ALW conditions, with mild inhibition and fast rate constants with triplets, but it also has weaknesses, including a pH-dependent reactivity. We evaluated the performance of both PTA and syringol (SYR) as triplet probes in aqueous extracts of particulate matter. While PTA is less sensitive to inhibition than SYR, it results in lower triplet concentrations, possibly because it is less reactive with weakly oxidizing triplets.
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Affiliation(s)
- Lan Ma
- Department of Land, Air, and Water Resources, University of California, Davis, California 95616, United States
| | - Reed Worland
- Department of Land, Air, and Water Resources, University of California, Davis, California 95616, United States
| | - Theo Tran
- Department of Land, Air, and Water Resources, University of California, Davis, California 95616, United States
| | - Cort Anastasio
- Department of Land, Air, and Water Resources, University of California, Davis, California 95616, United States
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17
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Houska J, Manasfi T, Gebhardt I, von Gunten U. Ozonation of lake water and wastewater: Identification of carbonous and nitrogenous carbonyl-containing oxidation byproducts by non-target screening. WATER RESEARCH 2023; 232:119484. [PMID: 36746701 DOI: 10.1016/j.watres.2022.119484] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/27/2022] [Accepted: 12/09/2022] [Indexed: 06/18/2023]
Abstract
Ozonation of drinking water and wastewater is accompanied by the formation of disinfection byproducts (DBPs) such as low molecular weight aldehydes and ketones from the reactions of ozone with dissolved organic matter (DOM). By applying a recently developed non-target workflow, 178 carbonous and nitrogenous carbonyl compounds were detected during bench-scale ozonation of two lake waters and three secondary wastewater effluent samples and full-scale ozonation of secondary treated wastewater effluent. An overlapping subset of carbonyl compounds (20%) was detected in all water types. Moreover, wastewater effluents showed a significantly higher fraction of N-containing carbonyl compounds (30%) compared to lake water (17%). All carbonyl compounds can be classified in 5 main formation trends as a function of increasing specific ozone doses. Formation trends upon ozonation and comparison of results in presence and absence of the •OH radical scavenger DMSO in combination with kinetic and mechanistic information allowed to elucidate potential carbonyl structures. A link between the detected carbonyl compounds and their precursors was established by ozonating six model compounds (phenol, 4-ethylphenol, 4-methoxyphenol, sorbic acid, 3-buten-2-ol and acetylacetone). About one third of the detected carbonous carbonyl compounds detected in real waters was also detected by ozonating model compounds. Evaluation of the non-target analysis data revealed the identity of 15 carbonyl compounds, including hydroxylated aldehydes and ketones (e.g. hydroxyacetone, confidence level (CL) = 1), unsaturated dicarbonyls (e.g. acrolein, CL = 1; 2-butene-1,4-dial, CL = 1; 4-oxobut-2-enoic acid, CL = 2) and also a nitrogen-containing carbonyl compound (2-oxo-propanamide, CL =1). Overall, this study shows the formation of versatile carbonous and nitrogenous carbonyl compounds upon ozonation involving ozone and •OH reactions. Carbonyl compounds with unknown toxicity might be formed, and it could be demonstrated that acrolein, malondialdehyde, methyl glyoxal, 2-butene-1,4-dial and 4-oxo-pentenal are degraded during biological post-treatment.
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Affiliation(s)
- Joanna Houska
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf 8600, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
| | - Tarek Manasfi
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf 8600, Switzerland
| | - Isabelle Gebhardt
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf 8600, Switzerland
| | - Urs von Gunten
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf 8600, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, Zurich 8092, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland.
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18
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Remke SC, Houska J, von Gunten U, Canonica S. Impact of chlorination and ozonation of dissolved organic matter on its photo-induced production of long-lived photooxidants and excited triplet states. WATER RESEARCH 2023; 239:119921. [PMID: 37230030 DOI: 10.1016/j.watres.2023.119921] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 03/19/2023] [Accepted: 03/26/2023] [Indexed: 05/27/2023]
Abstract
Recent studies suggested that long-lived photooxidants (LLPO), which are reactive intermediates formed during irradiation of dissolved organic matter (DOM), may consist of phenoxyl radicals derived from phenolic moieties of the DOM. Besides the well-studied excited triplet states of chromophoric DOM (3CDOM*), LLPO presumably are important photooxidants for the transformation of electron-rich contaminants in surface waters. The main objective of this study was to further test the potential role of phenoxyl radical as LLPO. Suwannee River fulvic acid (SRFA) as a model DOM was pre-oxidised using the phenol-reactive oxidants chlorine and ozone, followed by its characterization by the specific UV absorption at 254 nm (SUVA254), the ratio of absorbance at λ = 254 nm and λ = 365 nm (E2:E3), and the electron donating capacity (EDC). Subsequently, the photoreactivity of pre-oxidized SRFA was tested using 3,4-dimethoxyphenol (DMOP) as a LLPO probe compound at two initial concentrations ([DMOP]0 = 0.1 and 5.0 μM). Linear inter-correlations were observed for the relative changes in SUVA254, E2:E3, and EDC for increasing oxidant doses. Pseudo-first-order transformation rate constants normalized to the changing SRFA absorption rate (i.e., k0.1obs/rCDOMabsand k5.0obs/rCDOMabs, for 0.1 and 5.0 µM, respectively) exhibited the following distinct trends: The LLPO-dominated k0.1obs/rCDOMabsratio decreased with increasing oxidant dose and with decreasing SUVA254 and EDC, while the 3CDOM*-dominated k5.0obs/rCDOMabsratio positively correlated with E2:E3. Finally, it was concluded that precursors of 3CDOM* and LLPO are chemically modified differently by pre-oxidation of DOM, and LLPO precursors likely consist of phenolic moieties of DOM, suggesting phenoxyl radicals as LLPO.
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Affiliation(s)
- Stephanie C Remke
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Joanna Houska
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
| | - Silvio Canonica
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, CH-8600 Dübendorf, Switzerland
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19
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Li J, Zhang Z, Xiang Y, Jiang J, Yin R. Role of UV-based advanced oxidation processes on NOM alteration and DBP formation in drinking water treatment: A state-of-the-art review. CHEMOSPHERE 2023; 311:136870. [PMID: 36252895 DOI: 10.1016/j.chemosphere.2022.136870] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/07/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Oxidative treatment of drinking water has been practiced for more than a century. UV-based advanced oxidation processes (UV-AOPs) have emerged as promising oxidative treatment technologies to eliminate recalcitrant chemicals and biological contaminants in drinking water. UV-AOPs inevitably alter the properties of natural organic matter (NOM) and affect the disinfection byproduct (DBP) formation in the post-disinfection. This paper provides a state-of-the-art review on the effects of UV-AOPs on the changes of NOM properties and the consequent impacts on DBP formation in the post-chlorination process. A tutorial review to the connotations of NOM properties (e.g., bulk properties, fractional constituents, and molecular structures) and the associated state-of-the-art analytical methods are firstly presented. The impacts of different radical-based AOPs on the changes of NOM properties together with the underlying NOM-radical reaction mechanisms are discussed. The impacts of alteration of NOM properties on DBP formation in the post-chlorination process are then reviewed. The current knowledge gaps and future research needs are finally presented, with emphases on the needs to strengthen the comparability of research data in literature, the accuracy in quantifying the reactive moieties of NOM, and the awareness of unknown DBPs in oxidative water treatment processes. The review and discussion improve the fundamental understanding of NOM-radical and NOM-chlorine chemistry. They also provide useful implications on the engineering design and operation of next-generation drinking water treatment plants.
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Affiliation(s)
- Juan Li
- Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, Zhu Hai 519087, PR China; Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999066, Hong Kong, PR China.
| | - Zhong Zhang
- 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, PR China
| | - Yingying Xiang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999066, Hong Kong, PR 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, PR China
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999066, Hong Kong, PR China.
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20
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Qiu JL, Li DW, Jing SC, Qiu H, Liu FQ. Advanced technique of catalytic ozonation-enhanced coagulation for the efficient removal of low coagulability refractory organics from secondary effluent. CHEMOSPHERE 2022; 303:135157. [PMID: 35640692 DOI: 10.1016/j.chemosphere.2022.135157] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 05/23/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
The novel cascaded catalytic ozonation-enhanced coagulation process (FeCeAC/O3-PAC) was developed with much success towards second effluent organic matter (EfOM) in chemical industrial wastewater. Compared with the conventional techniques, FeCeAC/O3-PAC exhibited remarkable performances in the advanced removal of EfOM. The characteristics of EfOM and interactivities of reaction process played the crucial roles. Especially, the removal rate constant of soluble microbial products (SMPs) with FeCeAC/O3-PAC exceeded 55.38% versus FeCeAC/O3. The outstanding synergistic effect was contributed to the enhanced generation of active oxygen species by FeCeAC and PAC, which increased the content of oxygen-containing functional groups of EfOM and thus facilitated the interaction between PAC and EfOM. As the result, the larger-sized flocs could be formed and separated easily. Herein, this work found a far more effective way to remove EfOM especially low-coagulability refractory organics (LCRO) in chemical sewage plant.
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Affiliation(s)
- Jin-Li Qiu
- School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Da-Wei Li
- School of the Environment, Nanjing University, Nanjing, 210023, PR China; School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing, 210044, PR China
| | - Shi-Chao Jing
- School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Huan Qiu
- School of the Environment, Nanjing University, Nanjing, 210023, PR China
| | - Fu-Qiang Liu
- School of the Environment, Nanjing University, Nanjing, 210023, PR China.
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21
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Kämmler J, Zoumpouli GA, Sellmann J, Chew YMJ, Wenk J, Ernst M. Decolorization and control of bromate formation in membrane ozonation of humic-rich groundwater. WATER RESEARCH 2022; 221:118739. [PMID: 35716412 DOI: 10.1016/j.watres.2022.118739] [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: 02/03/2022] [Revised: 05/29/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
Membrane ozonation of bromide-containing, high-color natural organic matter (NOM) containing groundwater was performed using single-tube polydimethylsiloxane (PDMS) and multi-tube polytetrafluoroethylene (PTFE) membrane contactors, and compared to batch ozonation. For membrane ozonation, dissolved ozone concentration, water color (VIS436), ultraviolet light absorption (UV254) and bromate formation were correlated with ozone dose, ozone gas concentration, hydraulic retention time and Hatta number (Ha). NOM color removal of up to 45 % for the single-tube contactor and 17 % for the multi-tube contactor were achieved while containing bromate formation below 10 µg L-1. Higher color removal using higher ozone doses was associated with high bromate formation i.e. >>10 µg L-1. In membrane ozonation, low ozone gas concentrations, long hydraulic retention times and high Ha resulted in low dissolved ozone concentrations due to quenching of ozone by NOM. At specific ozone doses of < 0.5 mg O3/mg DOC and Ha > 1, single-tube ozonation resulted in comparable results to batch ozonation while bromate formation was higher in the single-tube contactor at specific ozone doses > 0.5 mg O3/mg DOC and Ha < 1. At comparable ozone doses and Ha, bromate formation in the multi-tube contactor was always higher compared to single-tube and batch ozonation. This could be associated with the uneven ozone distribution within the multi-tube contactor. Results show that ozone dose is the major driver for selectivity between bromate formation and NOM color removal in both membrane and batch ozonation. Bromate formation in membrane ozonation may be controlled by adjusting gas concentration, Ha and hydraulic retention time. Membrane module design and process parameters of membrane ozonation reactors significantly affect treatment performance and should be optimized for selective target compound removal over by-product formation.
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Affiliation(s)
- Jakob Kämmler
- Hamburg University of Technology, Institute for Water Resources and Water Supply, Am Schwarzenberg-Campus 3, 21073 Hamburg, Germany; DVGW Research Centre TUHH, Am Schwarzenberg-Campus 3, 21073 Hamburg, Germany
| | - Garyfalia A Zoumpouli
- Centre for Doctoral Training, Centre for Sustainable Chemical Technologies, University of Bath, Bath BA27AY, United Kingdom; Department of Chemical Engineering, University of Bath, Bath BA27AY, United Kingdom; Water Innovation & Research Centre (WIRC), University of Bath, Bath BA27AY, United Kingdom
| | - Jörn Sellmann
- Hamburg University of Technology, Institute for Water Resources and Water Supply, Am Schwarzenberg-Campus 3, 21073 Hamburg, Germany
| | - Y M John Chew
- Department of Chemical Engineering, University of Bath, Bath BA27AY, United Kingdom; Water Innovation & Research Centre (WIRC), University of Bath, Bath BA27AY, United Kingdom
| | - Jannis Wenk
- Department of Chemical Engineering, University of Bath, Bath BA27AY, United Kingdom; Water Innovation & Research Centre (WIRC), University of Bath, Bath BA27AY, United Kingdom.
| | - Mathias Ernst
- Hamburg University of Technology, Institute for Water Resources and Water Supply, Am Schwarzenberg-Campus 3, 21073 Hamburg, Germany; DVGW Research Centre TUHH, Am Schwarzenberg-Campus 3, 21073 Hamburg, Germany.
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22
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Mehmood CT, Tan W, Chen Y, Waheed H, Li Y, Xiao Y, Zhong Z. UV/O3 assisted ceramic membrane reactor for efficient fouling control and DOM transformations in real textile wastewater. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2022.121284] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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23
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Wünsch R, Hettich T, Prahtel M, Thomann M, Wintgens T, von Gunten U. Tradeoff between micropollutant abatement and bromate formation during ozonation of concentrates from nanofiltration and reverse osmosis processes. WATER RESEARCH 2022; 221:118785. [PMID: 35949072 DOI: 10.1016/j.watres.2022.118785] [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: 02/18/2022] [Revised: 06/02/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
Water treatment with nanofiltration (NF) or reverse osmosis (RO) membranes results in a purified permeate and a retentate, where solutes are concentrated and have to be properly managed and discharged. To date, little is known on how the selection of a semi-permeable dense membrane impacts the dissolved organic matter in the concentrate and what the consequences are for micropollutant (MP) abatement and bromate formation during concentrate treatment with ozone. Laboratory ozonation experiments were performed with standardized concentrates produced by three membranes (two NFs and one low-pressure reverse osmosis (LPRO) membrane) from three water sources (two river waters and one lake water). The concentrates were standardized by adjustment of pH and concentrations of dissolved organic carbon, total inorganic carbon, selected micropollutants (MP) with a low to high ozone reactivity and bromide to exclude factors which are known to impact ozonation. NF membranes had a lower retention of bromide and MPs than the LPRO membrane, and if the permeate quality of the NF membrane meets the requirements, the selection of this membrane type is beneficial due to the lower bromate formation risks upon concentrate ozonation. The bromate formation was typically higher in standardized concentrates of LPRO than of NF membranes, but the tradeoff between MP abatement and bromate formation upon ozonation of the standardized concentrates was not affected by the membrane type. Furthermore, there was no difference for the different source waters. Overall, ozonation of concentrates is only feasible for abatement of MPs with a high to moderate ozone reactivity with limited bromate formation. Differences in the DOM composition between NF and LPRO membrane concentrates are less relevant than retention of MPs and bromide by the membrane and the required ozone dose to meet a treatment target.
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Affiliation(s)
- R Wünsch
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, 4132 Muttenz, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - T Hettich
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, 4132 Muttenz, Switzerland
| | - M Prahtel
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, 4132 Muttenz, Switzerland; Chair of Urban Water Systems Engineering, Technical University of Munich, Garching, Germany
| | - M Thomann
- FHNW University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Institute for Ecopreneurship, 4132 Muttenz, Switzerland
| | - T Wintgens
- RWTH Aachen University, Institute of Environmental Engineering, 52074 Aachen, Germany
| | - U von Gunten
- School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland; Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland.
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24
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Maqbool T, Sun M, Chen L, Zhang Z. Exploring the fate of dissolved organic matter at the molecular level in the reactive electrochemical ceramic membrane system using fluorescence spectroscopy and FT-ICR MS. WATER RESEARCH 2022; 210:117979. [PMID: 34953213 DOI: 10.1016/j.watres.2021.117979] [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: 10/13/2021] [Revised: 12/10/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
This research evaluated the performance of reactive electrochemical ceramic membrane (REM) in treating secondary effluent and investigated the fate of dissolved organic matter (DOM) at the molecular level. The role of adsorption, electrosorption, and oxidation in DOM removal was comprehensively elucidated based on fluorescence spectroscopy and high-resolution mass spectrometry (FT-ICR MS). Among the fluorescence components (C1-C3) in secondary effluent, microbial humic-like C2 showed fewer adsorption on the REM surface without applying an electrical potential. The electrosorption helped an enhanced uptake of all DOM components and transformed them onto the electrode surface. The fluorescence components and all three fractions (hydrophilic, transphilic, and hydrophobic) were rapidly degraded, and finished water with stable DOM was obtained. The leading degradation phenomena were the change of the unsaturated compounds to the aliphatic and transformation of large-sized molecules to medium and small-sized ones. Above 70% of the compounds in the secondary effluent acted as precursors, which were mineralized/degraded and transformed products were found on the REM surface and in the finished water. The compounds containing sulfur (CHOS) were easily and preferably degraded/mineralized, followed by the compounds containing nitrogen (CHON) and CHO. The oxidation of DOM led to the extensive formation of organo-chlorinated compounds, which contributed above 80% in products. Overall, the combination of fluorescence spectroscopy and FT-ICR MS provided unique behavior of DOM in the secondary effluent toward electro-oxidation in the REM system. These findings could help explore the potential of REM for different water matrices to project the possible composition of DOM in the finished water.
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Affiliation(s)
- Tahir Maqbool
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, China; Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, Guangdong, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Mingming Sun
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, China; Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, Guangdong, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Li Chen
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, China; Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, Guangdong, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhenghua Zhang
- Institute of Environmental Engineering & Nano-Technology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, Guangdong, China; Guangdong Provincial Engineering Research Centre for Urban Water Recycling and Environmental Safety, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, Guangdong, China; School of Environment, Tsinghua University, Beijing 100084, China.
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25
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Walpen N, Joss A, von Gunten U. Application of UV absorbance and electron-donating capacity as surrogates for micropollutant abatement during full-scale ozonation of secondary-treated wastewater. WATER RESEARCH 2022; 209:117858. [PMID: 34864343 DOI: 10.1016/j.watres.2021.117858] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Revised: 10/19/2021] [Accepted: 11/08/2021] [Indexed: 06/13/2023]
Abstract
Ozonation of secondary-treated wastewater for the abatement of micropollutants requires a reliable control of ozone doses. Changes in the UV absorbance of dissolved organic matter (DOM) during ozonation allow to estimate micropollutant abatement on-line and were therefore identified as feed-back control parameter. In this study, the suitability of the electron-donating capacity (EDC) as an additional surrogate parameter which is independent of optical DOM properties was evaluated during full-scale ozonation. For this purpose, a recently developed EDC analyzer was enhanced to enable continuous on-line EDC and UV absorbance measurements. During a multi-week monitoring campaign at the wastewater treatment plant of Zurich, Switzerland, specific ozone doses were varied from 0.13 to 0.91 mgO3⋅mgDOC-1 and selected micropollutants with different ozone reactivities were analyzed by LC-MS in conjunction with bromate analysis by IC-MS. In agreement with previous laboratory studies, the relative residual UV absorbance and EDC both decreased exponentially as a function of the specific ozone dose and, in comparison to the residual UV absorbance, residual EDC values showed a more pronounced decrease at low specific ozone doses ≤0.34 mgO3⋅mgDOC-1. Logistic regression models allowed to estimate relative residual micropollutant concentrations in the ozonation effluent using either the residual UV absorbance or EDC as explanatory variable. Averaging those models along the explanatory variables allowed to estimate target values in relative residual UV absorbances and EDC for specific micropollutant abatement targets. In addition, both parameters allowed to identify conditions with elevated conversions of bromide to bromate. Taken together, these findings show that the integration of relative residual EDC values as a second control parameter can improve existing absorbance-based ozonation control systems to meet micropollutant abatement targets, particularly for treatment systems where low ozone doses are applied.
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Affiliation(s)
- Nicolas Walpen
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600 Dübendorf, Switzerland
| | - Adriano Joss
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600 Dübendorf, Switzerland
| | - Urs von Gunten
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600 Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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26
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Du J, Kim K, Min DW, Choi W. Freeze-Thaw Cycle-Enhanced Transformation of Iodide to Organoiodine Compounds in the Presence of Natural Organic Matter and Fe(III). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:1007-1016. [PMID: 34967617 DOI: 10.1021/acs.est.1c06747] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The formation of organoiodine compounds (OICs) is of great interest in the natural iodine cycle as well as water treatment processes. Herein, we report a pathway of OIC formation that reactive iodine (RI) and OICs are produced from iodide oxidation in the presence of Fe(III) and natural organic matter (NOM) in frozen solution, whereas their production is insignificant in aqueous solution. Moreover, thawing the frozen solution induces the further production of OICs. A total of 352 OICs are detected by Fourier transform ion cyclotron resonance mass spectrometry in the freeze-thaw cycled reactions of Fe(III)/I-/humic acid solution, which are five times as many as OICs in aqueous reactions. Using model organic compounds instead of NOM, aromatic compounds (e.g., phenol, aniline, o-cresol, and guaiacol) induce higher OIC formation yields (10.4-18.6%) in the freeze-thaw Fe(III)/I- system than those in aqueous (1.1-2.1%) or frozen (2.7-7.6%) solutions. In the frozen solution, the formation of RI is enhanced, but its further reaction with NOM is hindered. Therefore, the freeze-thaw cycle in which RI is formed in the frozen media and the resulting RI is consumed by reaction with NOM in the subsequently thawed solution is more efficient in producing OICs than the continuous reaction in frozen solution.
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Affiliation(s)
- Juanshan Du
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Kitae Kim
- Korea Polar Research Institute (KOPRI), Incheon 21990, Korea
| | - Dae Wi Min
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Wonyong Choi
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
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27
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Bravo C, De Nobili M, Gambi A, Martin-Neto L, Nascimento OR, Toniolo R. Kinetics of electron transfer reactions by humic substances: Implications for their biogeochemical roles and determination of their electron donating capacity. CHEMOSPHERE 2022; 286:131755. [PMID: 34365173 DOI: 10.1016/j.chemosphere.2021.131755] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
Humic substances (HS) possess redox active groups covering a wide range of potentials and are used by facultative anaerobic microorganisms as electron acceptors. To serve as suitable electron shuttles for anaerobic respiration, HS should be able to re-oxidize relatively quickly to prevent polarization of the surrounding medium. Mediated electrochemical oxidation and decolorization assays, based on the reduction of the radical ion of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) (ABTS•-) allow to determine the electron donating capacity (EDC) of HS, but uncertainties remain about the reaction time that should be allowed to obtain environmentally meaningful EDC values. In this work, we performed a kinetic analysis of the time trend of the reduction of ABTS•- by HS by Vis and Electron Paramagnetic Resonance (EPR) spectroscopies and by cyclic voltammetry. We found evidences of two concomitant separate mechanisms of electron exchange: a fast and a slow transfer processes which may have different environmental roles. These results can set a base to identify the appropriate conditions for the spectrophotometric determination of the fast and slow components of the EDC of HS.
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Affiliation(s)
- Carlo Bravo
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 208, Udine, I-33100, Italy; Department of Life Sciences, University of Trieste, Via Licio Giorgieri 5, Trieste, I-34128, Italy
| | - Maria De Nobili
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 208, Udine, I-33100, Italy.
| | - Alberto Gambi
- DPIA, University of Udine, Via del Cotonificio 108, Udine, I-33100, Italy
| | | | - Otaciro R Nascimento
- Institute of Physics of São Carlos (IFSC), University of São Paulo, CP 369, São Carlos-SP, 13560-970, Brazil
| | - Rosanna Toniolo
- Department of Agricultural, Food, Environmental and Animal Sciences, University of Udine, Via delle Scienze 208, Udine, I-33100, Italy
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28
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Houska J, Salhi E, Walpen N, von Gunten U. Oxidant-reactive carbonous moieties in dissolved organic matter: Selective quantification by oxidative titration using chlorine dioxide and ozone. WATER RESEARCH 2021; 207:117790. [PMID: 34740166 DOI: 10.1016/j.watres.2021.117790] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 10/15/2021] [Accepted: 10/18/2021] [Indexed: 06/13/2023]
Abstract
The application of oxidants for disinfection or micropollutant abatement during drinking water and wastewater treatment is accompanied by oxidation of matrix components such as dissolved organic matter (DOM). To improve predictions of the efficiency of oxidation processes and the formation of oxidation products, methods to determine concentrations of oxidant-reactive phenolic, olefinic or amine-type DOM moieties are critical. Here, a novel selective oxidative titration approach is presented, which is based on reaction kinetics of oxidation reactions towards certain DOM moieties. Phenolic moieties were determined by oxidative titration with ClO2 and O3 for five DOM isolates and two secondary wastewater effluent samples. The determined concentrations of phenolic moieties correlated with the electron-donating capacity (EDC) and the formation of inorganic ClO2-byproducts (HOCl, ClO2-, ClO3-). ClO2-byproduct yields from phenol and DOM isolates and changes due to the application of molecular tagging for phenols revealed a better understanding of oxidant-reactive structures within DOM. Overall, oxidative titrations with ClO2 and O3 provide a novel and promising tool to quantify oxidant-reactive moieties in complex mixtures such as DOM and can be expanded to other matrices or oxidants.
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Affiliation(s)
- Joanna Houska
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600 Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Elisabeth Salhi
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600 Dübendorf, Switzerland
| | - Nicolas Walpen
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600 Dübendorf, Switzerland
| | - Urs von Gunten
- Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600 Dübendorf, Switzerland; Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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29
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Wang WL, Lee MY, Du Y, Zhou TH, Yang ZW, Wu QY, Hu HY. Understanding the influence of pre-ozonation on the formation of disinfection byproducts and cytotoxicity during post-chlorination of natural organic matter: UV absorbance and electron-donating-moiety of molecular weight fractions. ENVIRONMENT INTERNATIONAL 2021; 157:106793. [PMID: 34332302 DOI: 10.1016/j.envint.2021.106793] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 07/14/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
Pre-ozonation can reduce the formation of disinfection byproducts (DBPs) and related adverse effects during subsequent chlorination, but the change of each molecular weight (MW) fraction during each step of combined pre-ozonation and post-chlorination has not been well illustrated. In this study, it was investigated in terms of electron-donating-moieties (EDMs) and UVA254 for a representative natural organic matter from Suwanee river (SRNOM). Pre-ozonation suppressed the post-chlorination of SRNOM through oxidation of almost all EDMs (>85%) and UVA254 (>90%) in high MW fractions (HMW, >3.2 kDa) and moderate EDMs (43%) and UVA254 (72%) in medium MW fractions (MMW, 1.0-3.2 kDa). Furthermore, pre-ozonation led to comparable abatements of EDMs and UVA254 for HMW fractions, but lower abatement of EDMs than UVA254 for MMW fractions. However, when t-BuOH was used as an •OH-quencher, pre-ozonation led to a few instances in which there were higher abatements of EDMs than UVA254 for the MMW fraction. These findings suggested that the HMW fraction dominantly underwent ring-cleavage of phenols via O3- or •OH-oxidation. Differently, the MMW fraction underwent ring-cleavage of phenols and quinones-formation via O3-oxidation, but occasionally underwent hydroxylation and hydro-phenol formation via •OH-oxidation. Because of forehand elimination of reactive moieties (e.g. EDMs), pre-ozonation obviously inhibited the formation of representative DBPs (67%-84% inhibition), total organic chloride (51% inhibition) and cytotoxicity (31% inhibition), but may have promoted the formation of carbonyl-DBPs (trichloroacetone and chloral hydrate). When compared with UVA254, EDMs would better for surrogate of DBPs formation. EDM abatement surrogated the formation of total organic chlorine (TOCl) and cytotoxicity following a two-stage phase, possibly because the speciation of DBPs and transformation products varied with the abatement of EDMs.
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Affiliation(s)
- Wen-Long Wang
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China
| | - Min-Yong Lee
- Department of Environmental Resources Research, National Institute of Environmental Research, Seogu, Incheon 22689, Republic of Korea
| | - Ye Du
- College of Architecture & Environment, Sichuan University, Chengdu 610000, PR China
| | - Tian-Hui Zhou
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China
| | - Zheng-Wei Yang
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China
| | - Qian-Yuan Wu
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China.
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, PR China
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30
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Hu S, Jin X, Yang C, Wang Y, Xie X, Zhang S, Jin P, Wang XC. Enhanced complexation of humic acids: Homogenization of protonated groups in the hybrid ozonation-coagulation process. CHEMOSPHERE 2021; 280:130647. [PMID: 33932908 DOI: 10.1016/j.chemosphere.2021.130647] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 04/20/2021] [Accepted: 04/23/2021] [Indexed: 06/12/2023]
Abstract
In this study, we compared dissolved organic carbon (DOC) and UV254 removal efficiencies of the hybrid ozonation-coagulation (HOC) and pre-ozonation-coagulation (POC) processes for humic acid (HA) at pH 5 with AlCl3•6H2O as the coagulant. The DOC and UV254 removal efficiencies of the HOC process were higher than those of the POC process at ozone dosages less than 2.0 mg O3 (mg DOC)-1. The ozone dosage was optimized at 0.3 and 0.1 mg O3 (mg DOC)-1 for the HOC and POC processes, respectively, implying a more rigorous ozone dosage for the POC process. During the POC process, pre-ozonation was observed to increase the binding sites of HA (e.g., hydroxyl and carboxyl groups), improving the complexation of dissolved organic matter. For the HOC process, in addition to its role in the oxidation of organic matter, ozone also reacted with coagulants. The reaction between ozone and coagulants can facilitate the formation of Al13. Moreover, the oxidation of •OH and ozone can increase the charge density of the HA binding sites, homogenizing the binding sites of HA and enhancing the complexation with Al13.
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Affiliation(s)
- Shiyi Hu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China
| | - Xin Jin
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China
| | - Chao Yang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China
| | - Yong Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China
| | - Xinyue Xie
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China
| | - Shaohua Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China
| | - Pengkang Jin
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China; School of Human Settlements and Civil Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710049, China.
| | - Xiaochang C Wang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, Shaanxi Province, 710055, China
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31
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Jahan BN, Li L, Pagilla KR. Fate and reduction of bromate formed in advanced water treatment ozonation systems: A critical review. CHEMOSPHERE 2021; 266:128964. [PMID: 33250222 DOI: 10.1016/j.chemosphere.2020.128964] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/19/2020] [Accepted: 11/10/2020] [Indexed: 06/12/2023]
Abstract
Disinfection in water treatment and reclamation systems eliminates the potential health risks associated with waterborne pathogens, however it may produce disinfection by-products (DBPs) harmful to human health. Potentially carcinogenic bromate is a DBP formed during the ozonation of bromide-containing waters. To mitigate the problem of bromate formation, different physical/chemical or biological reduction methods of bromate have been investigated. Until now, adsorption-based physical method has proven to be more effective than chemical methods in potable water treatment. Though several studies on biological reduction methods have been carried out in a variety of bioreactor systems, such as in biologically active carbon filters and denitrifying bioreactors, the microbiological mechanisms or biochemical pathways of bromate minimization have not been clearly determined to date. Genetic analysis could provide a broader picture of microorganisms involved in bromate reduction which might show cometabolic or respiratory pathways, and affirm the synergy functions between different contributing groups. The hypothesis established from the diffusion coefficients of different electron donor and acceptors, illustrates that some microorganisms preferring bromate over oxygen contain specific enzymes which lower the activation energy required for bromate reduction. In addition, considering microbial bromate reduction as an effective treatment strategy; field scale investigations are required to observe quantitative correlations of various influencing parameters such as pH, ozone dose, additives or constituents such as ammonia, hydrogen peroxide, and/or chloramine, dissolved organic carbon levels, dissolved oxygen gradient within biofilm, and empty bed contact time on bromate removal or reduction.
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Affiliation(s)
- Begum Nazia Jahan
- Graduate Research Assistant, Civil and Environmental Engineering, University of Nevada, Reno, NV, USA
| | - Lin Li
- Post-Doctoral Researcher, Civil and Environmental Engineering, University of Nevada, Reno, NV, USA
| | - Krishna R Pagilla
- Chair, Civil and Environmental Engineering, University of Nevada, Reno, NV, USA.
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32
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Rougé V, von Gunten U, Allard S. Efficiency of pre-oxidation of natural organic matter for the mitigation of disinfection byproducts: Electron donating capacity and UV absorbance as surrogate parameters. WATER RESEARCH 2020; 187:116418. [PMID: 33011567 DOI: 10.1016/j.watres.2020.116418] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 06/11/2023]
Abstract
Pre-oxidation is often used before disinfection with chlorine to decrease the reactivity of the water matrix and mitigate the formation of regulated disinfection byproducts (DBPs). This study provides insights on the impact of oxidative pre-treatment with chlorine dioxide (ClO2), ozone (O3), ferrate (Fe(VI)) and permanganate (Mn(VII)) on Suwannee River Natural Organic Matter (SRNOM) properties characterized by the UV absorbance at 254 nm (UV254) and the electron donating capacity (EDC). Changes in NOM reactivity and abatement of DBP precursors are also assessed. The impact of pre-oxidants (based on molar concentration) on UV254 abatement ranked in the order O3 > Mn(VII) > Fe(VI)/ClO2, while the efficiency of pre-oxidation on EDC abatement followed the order Mn(VII) > ClO2 > Fe(VI) > O3 and two phases were observed. At low specific ClO2, Fe(VI) and Mn(VII) doses corresponding to < 50% EDC abatement, a limited relative abatement of UV254 compared to the EDC was observed (~ 8% EDC abatement per 1% UV254 abatement). This suggests the oxidation of phenolic-type moieties to quinone-type moieties which absorb UV254 and don't contribute to EDC. At higher oxidant doses (> 50% EDC abatement), a similar abatement of EDC and UV254 (~ 0.9-1.2% EDC abatement per 1% UV254 abatement) suggested aromatic ring cleavage. In comparison to the other oxidants, O3 abated the relative UV254 more effectively, due to a more efficient cleavage of aromatic rings. For a pre-oxidation with Mn(VII), ClO2 and Fe(VI), similar correlations between the EDC abatement and the chlorine demand or the adsorbable organic halide (AOX) formation were obtained. In contrast, O3 pre-treatment led to a lower chlorine demand and AOX formation for equivalent EDC abatement. For all oxidants, trihalomethane formation was poorly correlated with both EDC and UV254. The EDC abatement was found to be a pre-oxidant-independent surrogate for haloacetonitrile formation. These results emphasize the benefits of combining EDC and UV254 measurement to understand and monitor oxidant-induced changes of NOM and assessing DBP formation.
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Affiliation(s)
- Valentin Rougé
- Curtin Water Quality Research Centre, Department of Chemistry, Curtin University, GPO Box U1987, 6845 Perth, Western Australia, Australia; School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea
| | - Urs von Gunten
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland; School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale Lausanne (EPFL), CH-1015 Lausanne, Switzerland; ETH Zurich, Swiss Federal Institute of Technology, Institute of Biogeochemistry and Pollutant Dynamics (IBP), Department of Environment Systems (D-USYS), Universitätstrasse 16, CH-8092 Zürich.
| | - Sébastien Allard
- Curtin Water Quality Research Centre, Department of Chemistry, Curtin University, GPO Box U1987, 6845 Perth, Western Australia, Australia.
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Remucal CK, Salhi E, Walpen N, von Gunten U. Molecular-Level Transformation of Dissolved Organic Matter during Oxidation by Ozone and Hydroxyl Radical. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:10351-10360. [PMID: 32697081 DOI: 10.1021/acs.est.0c03052] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Ozonation of drinking and wastewater relies on ozone (O3) and hydroxyl radical (•OH) as oxidants. Both oxidants react with dissolved organic matter (DOM) and alter its composition, but the selectivity of the two oxidants and mechanisms of reactivity with DOM moieties are largely unknown. The reactions of O3 and •OH with two DOM isolates were studied by varying specific ozone doses (0.1-1.3 mg-O3/mg-C) at pH 7. Additionally, conditions that favor O3 (i.e., addition of an •OH scavenger) or •OH (i.e., pH 11) were investigated. Ozonation decreases aromaticity, apparent molecular weight, and electron donating capacity (EDC) of DOM with large changes observed when O3 is the main oxidant (e.g., EDC decreases 63-77% for 1.3 mg-O3/mg-C). Both O3 and •OH react with highly aromatic, reduced formulas detected using high-resolution mass spectrometry (O:C = 0.48 ± 0.12; H:C = 1.06 ± 0.23), while •OH also oxidizes more saturated formulas (H:C = 1.64 ± 0.26). Established reactions between model compounds and O3 (e.g., addition of one to two oxygen atoms) or •OH (e.g., addition of one oxygen atom and decarboxylation) are observed and produce highly oxidized DOM (O:C > 1.0). This study provides molecular-level evidence for the selectivity of O3 as an oxidant within DOM.
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Affiliation(s)
- 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
| | - Elisabeth Salhi
- Swiss Federal Institute of Aquatic Science and Technology (Eawag),8600 Dübendorf, Switzerland
| | - Nicolas Walpen
- Swiss Federal Institute of Aquatic Science and Technology (Eawag),8600 Dübendorf, Switzerland
| | - Urs von Gunten
- Swiss Federal Institute of Aquatic Science and Technology (Eawag),8600 Dübendorf, Switzerland
- School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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