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Kaly MK, Rahman ME, Rana MS, Acharjee UK, Nasirujjaman K. Genotoxic effects of NDMA-contaminated ranitidine on Allium cepa cells and unveiling carcinogenic mechanisms via DFT and molecular dynamics simulation study. Sci Rep 2024; 14:31419. [PMID: 39733169 PMCID: PMC11682305 DOI: 10.1038/s41598-024-82984-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Accepted: 12/10/2024] [Indexed: 12/30/2024] Open
Abstract
This study investigated the potential genotoxic and carcinogenic effects of N-nitrosodimethylamine (NDMA), a hazardous compound found in ranitidine formulations that are used to treat excessive stomach acid. The study first examined the effects of NDMA-contaminated ranitidine formulation on Allium cepa root growth and mitotic activity. The results demonstrated dose-dependent decreases in both root growth and mitotic index indicating genotoxicity and cell division disruption. Elevated concentrations of ranitidine correlated with increased chromosomal aberrations indicating genotoxic capabilities. These outcomes underscored that NDMA contaminated ranitidine exposure triggers genotoxicity hampering cell division and inducing chromosomal aberrations. Electronic characteristics of NDMA revealed its electrophilic nature suggesting its capability to create covalent adducts with DNA bases fostering genotoxic and carcinogenic characteristics. Molecular docking analysis showed the interactions of NDMA with DNA including hydrogen bonds and carbon-hydrogen interactions with nucleotide bases forming DNA adducts. Molecular dynamics simulations showcased the dynamic behavior of the DNA-NDMA complex over time with structural fluctuations. Dynamic hydrogen bond fluctuations implied interactive intricacies between solute and solvent molecules. Overall, this study illuminates how NDMA-contaminated ranitidine could trigger DNA damage and potentially contribute to carcinogenesis. It emphasizes the urgency of minimizing exposure to this perilous and hazardous compound.
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Affiliation(s)
- Mst Kusum Kaly
- Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Md Ekhtiar Rahman
- Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Md Sohel Rana
- Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Uzzal Kumar Acharjee
- Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh
| | - Khondokar Nasirujjaman
- Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, 6205, Bangladesh.
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2
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Li J, Hua Z, Qin W, Chen C, Zhu B, Ruan T, Xiang Y, Fang J. Probing nitro(so) and chloro byproducts and their precursors in natural organic matter during UV/NH 2Cl treatment by FT-ICR MS with machine learning insights. WATER RESEARCH 2024; 262:122097. [PMID: 39018583 DOI: 10.1016/j.watres.2024.122097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 07/01/2024] [Accepted: 07/13/2024] [Indexed: 07/19/2024]
Abstract
The UV/monochloramine (UV/NH2Cl) process, while efficiently eliminating micropollutants, produces toxic byproducts. This study utilized Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) to investigate molecular-level changes in natural organic matter (NOM) and to disclose formation pathways of nitro(so) and chloro byproducts in the UV/NH2Cl process. The UV/NH2Cl process significantly increased the saturation and oxidation levels and altered the elemental composition of NOM. Using 15N labeling and a screening workflow, nitro(so) byproducts with nitrogen originating from inorganic sources (i.e., reactive nitrogen species (RNS) and/or NH2Cl) were found to exhibit total intensities comparable to those from NOM. RNS, rather than NH2Cl, played a significant role in incorporating nitrogen into NOM. Through linkage analysis, nitro(so) addition emerged as an important reaction type among the 25 reaction types applied. By using phenol as a representative model compound, the nitro byproducts were confirmed to be mainly generated through the oxidation of nitroso byproducts instead of nitration. Machine learning and SHAP analysis further identified the major molecular indices distinguishing nitro(so) and chloro precursors from non-precursors. This study enhances our fundamental understanding of the mechanisms driving the generation of nitro(so) and chloro byproducts from their precursors in complex NOM during the UV/NH2Cl process.
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Affiliation(s)
- Junfang Li
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, PR China; College of Chemistry and Chemical Engineering, Xinjiang Agricultural University, Urumqi, 830052, PR China
| | - Zhechao Hua
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Wenlei Qin
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Chunyan Chen
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, PR China
| | - Bao Zhu
- Research Centre for Eco-Environmental Sciences, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Beijing, 100085, PR China
| | - Ting Ruan
- Research Centre for Eco-Environmental Sciences, State Key Laboratory of Environmental Chemistry and Ecotoxicology, Beijing, 100085, PR China
| | - Yingying Xiang
- Nanyang Environment & Water Research Institute, Nanyang Technological University, 637141, Singapore; Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 000, Hong Kong SAR, PR China.
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou, 510275, PR China.
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3
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Pu C, Cavarra BR, Zeng T. Combining High-Resolution Mass Spectrometry and Chemiluminescence Analysis to Characterize the Composition and Fate of Total N-Nitrosamines in Wastewater Treatment Plants. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024. [PMID: 39254226 PMCID: PMC11428135 DOI: 10.1021/acs.est.4c06555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/11/2024]
Abstract
Monitoring the prevalence and persistence of N-nitrosamines and their precursors in wastewater treatment plants (WWTPs) and effluent-receiving aquatic compartments is a priority for utilities practicing wastewater recycling or exploiting wastewater-impacted source waters. In this work, we developed an analytical framework that combines liquid chromatography-high-resolution mass spectrometry (LC-HRMS) with acidic triiodide-chemiluminescence analysis to characterize the composition and fate of total N-nitrosamines (TONO) and their precursors along the treatment trains of eight WWTPs in New York. Through the parallel application of LC-HRMS and chemiluminescence methods, the TONO scores for 41 N-nitrosamines containing structurally diverse substituents on their amine nitrogen were derived based on their solid-phase extraction recoveries and conversion efficiencies to nitric oxide. Correcting the compositional analysis of TONO using the TONO scores of target N-nitrosamines refined the assessment of the reduction or accumulation of TONO and their precursors across treatment steps in WWTPs. Nontargeted analysis prioritized seven additional N-nitrosamines for confirmation by reference standards, including three previously uncharacterized species: N-nitroso-tert-butylphenylamine, N-nitroso-2-pyrrolidinmethanol, and N-nitrosodesloratadine, although they only served as minor components of TONO. Overall, our study establishes an adaptable methodological framework for advancing the quantitative and qualitative analysis of specific and unknown components of TONO across water treatment and reuse scenarios.
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Affiliation(s)
- Changcheng Pu
- Department of Civil and Environmental Engineering, Syracuse University, 151 Link Hall, Syracuse, New York 13244, United States
| | - Benjamin R Cavarra
- Department of Civil and Environmental Engineering, Syracuse University, 151 Link Hall, Syracuse, New York 13244, United States
| | - Teng Zeng
- Department of Civil and Environmental Engineering, Syracuse University, 151 Link Hall, Syracuse, New York 13244, United States
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Zhao J, Gong W, Yin R, Shang C, Mitch WA. Control of Aromatic Disinfection Byproducts in Potable Reuse Water by the UV 222/H 2O 2 vs UV 254/H 2O 2 Advanced Oxidation Processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:15846-15854. [PMID: 39169482 DOI: 10.1021/acs.est.4c05181] [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: 08/23/2024]
Abstract
Research has demonstrated the difficulty associated with degrading the conventional 1-2 carbon aliphatic halogenated byproducts of disinfectant reactions with organic matter [disinfection byproducts (DBPs)] within advanced oxidation process (AOP) units in potable reuse trains, but the efficacy of AOP units for treating the emerging classes of halogenated aromatic DBPs is unclear. We herein demonstrate more effective removal of 28 halogenated aromatic DBPs in the UV/H2O2 AOP at 222 nm (UV222) than in the conventional UV/H2O2 AOP at 254 nm. Direct photolysis of 28 halogenated aromatic DBPs was greatly enhanced at 222 nm with fluence-based photodecay rate constants of 4.31 × 10-4-1.53 × 10-2 cm2 mJ-1, which was mainly attributed to the higher molar absorption coefficients of halogenated aromatic DBPs at 222 nm than 254 nm. Generally, quantum yields of halogenated aromatic DBPs at both 222 and 254 nm followed the order of halophenols > halohydroxybenzaldehydes > halonitrophenols. All 28 halogenated aromatic DBPs exhibit high reactivity toward HO• with second-order rate constants ranging from 2.18 × 109 to 1.15 × 1010 M-1 s-1 determined by X-ray radiolysis. The UV fluence required to achieve 90% loss of halogenated aromatic DBPs in the UV222/H2O2 AOP was 75-95% lower than that in the UV254/H2O2 AOP, and 90% removal of most tested halogenated aromatic DBPs can be achieved in the UV222/H2O2 AOP within the UV fluence levels commonly applied in potable reuse (700-1000 mJ cm-2).
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Affiliation(s)
- Jing Zhao
- Department of Civil and Environmental Engineering, Stanford University, 473 Via Ortega, Stanford, California 94305, United States
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong, China
| | - Weiran Gong
- Department of Civil and Environmental Engineering, Stanford University, 473 Via Ortega, Stanford, California 94305, United States
| | - Ran Yin
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
- Institute for the Environment and Health, Nanjing University Suzhou Campus, Suzhou 215163, China
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong, China
- Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 999077, Hong Kong SAR, China
| | - William A Mitch
- Department of Civil and Environmental Engineering, Stanford University, 473 Via Ortega, Stanford, California 94305, United States
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Sun W, Ao X, Lu D, Zhang Y, Xue Y, He S, Zhang X, Mao T. Ultraviolet technology application in urban water supply and wastewater treatment in China: Issues, challenges and future directions. WATER RESEARCH X 2024; 23:100225. [PMID: 38711797 PMCID: PMC11070615 DOI: 10.1016/j.wroa.2024.100225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 04/01/2024] [Accepted: 04/24/2024] [Indexed: 05/08/2024]
Abstract
This study thoroughly explores the application of Ultraviolet (UV) water treatment technology in urban wastewater treatment and water supply in China, highlighting its crucial role in enhancing water quality safety. UV technology, with its environmentally friendly and low-carbon characteristics, is deemed more in line with the demands of sustainable development compared to traditional chemical disinfection methods. The widespread application of UV technology in urban wastewater treatment in China, particularly in the context of urban sewage treatment, is examined. However, to better promote and apply UV technology, there is a need to deepen the understanding of this technology and its application among a broad base of users and design units. The importance of gaining in-depth knowledge about the performance of UV water treatment equipment, the design calculation basis, and operational considerations, as well as the ongoing development of relevant standards, is underscored to ensure that the equipment used in projects complies with engineering design and production requirements. Furthermore, the positive trend of UV technology in the field of advanced oxidation, indicating a promising trajectory for engineering applications, is pointed out. Regarding the prospects of industrial development, a thorough analysis is conducted in the article, emphasizing the necessity for all stakeholders to collaborate and adopt a multi-level approach to promote the sustainable development and application of UV water treatment technology. This collaborative effort is crucial for providing effective safeguards for China's environment, ecology, and human health.
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Affiliation(s)
- Wenjun Sun
- School of Environment, Tsinghua University, Beijing 100084, PR China
- Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou 215163, PR China
- Chinese Ultraviolet Association, China Association of Machinery Industry for Environmental Protection, Beijing 100825, PR China
| | - Xiuwei Ao
- Chinese Ultraviolet Association, China Association of Machinery Industry for Environmental Protection, Beijing 100825, PR China
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, PR China
| | - Dongming Lu
- Chinese Ultraviolet Association, China Association of Machinery Industry for Environmental Protection, Beijing 100825, PR China
| | - Yuanna Zhang
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yanei Xue
- School of Environment, Tsinghua University, Beijing 100084, PR China
- Chinese Ultraviolet Association, China Association of Machinery Industry for Environmental Protection, Beijing 100825, PR China
| | - Siyuan He
- School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xi Zhang
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, PR China
| | - Ted Mao
- School of Environment, Tsinghua University, Beijing 100084, PR China
- Chinese Ultraviolet Association, China Association of Machinery Industry for Environmental Protection, Beijing 100825, PR China
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Zhou Y, Fu J, Zeng Z, Gao Y, Zhang Z, Han B, Ma J, Jiang J. Oxidation of amine-based pharmaceuticals with unactivated peroxymonosulfate: Kinetics, mechanisms, and elimination efficiency of NDMA formation. JOURNAL OF HAZARDOUS MATERIALS 2024; 463:132961. [PMID: 37951171 DOI: 10.1016/j.jhazmat.2023.132961] [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: 05/06/2023] [Revised: 10/24/2023] [Accepted: 11/07/2023] [Indexed: 11/13/2023]
Abstract
Amine-based pharmaceuticals are a significant class of N-nitrosodimethylamine (NDMA) precursors. This study investigated the use of unactivated peroxymonosulfate (PMS) to control amine-based pharmaceuticals and their NDMA formation potential. Kinetic analysis and product identification revealed that sumatriptan and doxylamine primarily underwent reactions at their tertiary amine group, while ranitidine and nizatidine had both tertiary amine and thioether group as reaction sites. The NDMA formation from sumatriptan and doxylamine during post-chloramination was significantly reduced with the abatement of the parent contaminants, while the formation of NDMA remained high even if full abatement of ranitidine and nizatidine was achieved. Product formation kinetics and reference standard tests revealed the great contribution of transformation products to NDMA formation. Ranitidine could be oxidized to sulfoxide-type product ranitidine-SO and N-oxide type product ranitidine-NO. Ranitidine-SO exhibited a high NDMA yield comparable to that of ranitidine (>90%), while ranitidine-NO showed a low NDMA yield (2%). With further oxidation of ranitidine-SO at the tertiary amine group, NDMA formation was reduced by more than 90%. The underlying mechanism for the importance of the tertiary amine group in NDMA formation was demonstrated by quantum chemical calculation. These findings underscore the potential of PMS pre-oxidation on NDMA control.
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Affiliation(s)
- Yang Zhou
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Junhao Fu
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Zhu Zeng
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Yuan Gao
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
| | - Zhong Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China.
| | - Bin Han
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Jinxing Ma
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Jin Jiang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
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7
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Wang J, Xu J, Kim J, Huang CH. Mechanistic Insight for Disinfection Byproduct Formation Potential of Peracetic Acid and Performic Acid in Halide-Containing Water. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18898-18908. [PMID: 37489812 PMCID: PMC10690735 DOI: 10.1021/acs.est.3c00670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 06/26/2023] [Accepted: 07/03/2023] [Indexed: 07/26/2023]
Abstract
Peracetic acid (PAA) and performic acid (PFA) are two major peroxyacid (POA) oxidants of growing usage. This study reports the first systematic evaluation of PAA, PFA, and chlorine for their disinfection byproduct (DBP) formation potential in wastewater with or without high halide (i.e., bromide or iodide) concentrations. Compared with chlorine, DBP formation by PAA and PFA was minimal in regular wastewater. However, during 24 h disinfection of saline wastewater, PAA surprisingly produced more brominated and iodinated DBPs than chlorine, while PFA effectively kept all tested DBPs at bay. To understand these phenomena, a kinetic model was developed based on the literature and an additional kinetic investigation of POA decay and DBP (e.g., bromate, iodate, and iodophenol) generation in the POA/halide systems. The results show that PFA not only oxidizes halides 4-5 times faster than PAA to the corresponding HOBr or HOI but also efficiently oxidizes HOI/IO- to IO3-, thereby mitigating iodinated DBP formation. Additionally, PFA's rapid self-decay and slow release of H2O2 limit the HOBr level over the long-term oxidation in bromide-containing water. For saline water, this paper reveals the DBP formation potential of PAA and identifies PFA as an alternative to minimize DBPs. The new kinetic model is useful to optimize oxidant selection and elucidate involved DBP chemistry.
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Affiliation(s)
- Junyue Wang
- School of Civil and Environmental
Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | | | - Juhee Kim
- School of Civil and Environmental
Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Ching-Hua Huang
- School of Civil and Environmental
Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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8
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Hua Z, Liang J, Wang D, Zhou Z, Fang J. Formation Mechanisms of Nitro Products from Transformation of Aliphatic Amines by UV/Chlorine Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:18754-18764. [PMID: 37294018 DOI: 10.1021/acs.est.3c00744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Formation of nitrogenous disinfection byproducts from aliphatic amines is a widespread concern owing to the serious health risks associated with them. However, the mechanisms of transforming aliphatic amines and forming nitro products in the UV/chlorine process have rarely been discussed, which are investigated in this work. Initially, secondary amines (R1R2NH) are transformed into secondary organic chloramines (R1R2NCl) via chlorination. Subsequently, radicals, such as HO• and Cl•, are found to contribute predominantly to such transformations. The rate constants at which HO•, Cl•, and Cl2•- react with R1R2NCl are (2.4-5.1) × 109, (1.5-3.8) × 109, and (1.2-6.1) × 107 M-1 s-1, respectively. Consequently, R1R2NCl are transformed into primary amines (R1NH2/R2NH2) and chlorinated primary amines (R1NHCl/R2NHCl and R1NCl2/R2NCl2) by excess chlorine. Furthermore, primarily driven by UV photolysis, chlorinated primary amines can be transformed into nitroalkanes with conversion rates of ∼10%. Dissolved oxygen and free chlorine play crucial roles in forming nitroalkanes, and post-chlorination can further form chloronitroalkanes, such as trichloronitromethane (TCNM). Radicals are involved in forming TCNM in the UV/chlorine process. This study provides new insights into the mechanisms of transforming aliphatic amines and forming nitro products using the UV/chlorine process.
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Affiliation(s)
- Zhechao Hua
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Jieying Liang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Ding Wang
- General Institute of Water Resources and Hydropower Planning and Design, Beijing 100120, China
| | - Zhihong Zhou
- Guangzhou Ecological Environmental Monitoring Center, Guangzhou 510006, China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
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Chuang YH, Chen TY, Chou CS, Chu LK, Hou CY, Szczuka A. Critical Role of Trichloramine Interaction with Dichloramine for N-Nitrosamine Formation during Breakpoint Chlorination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:15232-15242. [PMID: 37603422 DOI: 10.1021/acs.est.3c03326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
Breakpoint chlorination is prevalent in drinking water and potable reuse water treatment. Breakpoint chlorination enhances the formation of N-nitrosamines through reactions that form nitrosating agents. The most recent study suggests that nitroxyl (HNO) can react with free chlorine (HOCl) to form the nitrosyl chloride (ClNO) nitrosating agent but has not experimentally verified its importance in breakpoint chlorination. This study first assessed the formation of N-nitrosamines from model N-chloro-alkylamine precursors when they were added to a mixture of HOCl and HNO-derived nitrosating agents generated by chlorinating hydroxyurea. Results demonstrated negligible N-nitrosamine formation. Instead, we observed that the interaction of NCl3 with NHCl2 (total Cl2/total N molar ratio = 2.4-3:1) produced an intermediate capable of nitrosating N-chloro-alkylamines to N-nitrosamines at yields 8-fold higher to those observed in NHCl2 treatment alone, within a very short timescale (<3 min). We examined the stoichiometry of the reaction of NCl3 with NHCl2 using a UV-spectrum-based approach. Nitrosyl chloride was proposed as the key intermediate, likely formed alongside the reformation of NHCl2. Further isotopic experiments, byproduct measurements, and kinetic modeling supported the hypotheses. Modeling indicated that the reaction of NCl3 with NHCl2 explained ∼75% of NDMA formation during breakpoint chlorination. Because NCl3 is mainly derived from the reaction of HOCl with NHCl2, controlling NHCl2 (e.g., with additional treatment) is critical for minimizing nitrosamine formation in waters where breakpoint chlorination occurs.
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Affiliation(s)
- Yi-Hsueh Chuang
- Institute of Environmental Engineering, National Yang Ming Chiao Tung University, 1001, University Rd., Hsinchu City 30010, Taiwan
| | - Ting-Yuan Chen
- Institute of Environmental Engineering, National Yang Ming Chiao Tung University, 1001, University Rd., Hsinchu City 30010, Taiwan
| | - Chia-Shun Chou
- Institute of Environmental Engineering, National Yang Ming Chiao Tung University, 1001, University Rd., Hsinchu City 30010, Taiwan
| | - Li-Kang Chu
- Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| | - Chun-Yao Hou
- Department of Chemistry, National Tsing Hua University, 101, Sec 2, Kuang-Fu Rd., Hsinchu 300044, Taiwan
| | - Aleksandra Szczuka
- Department of Civil and Environmental Engineering, University of Michigan, 1351 Beal Ave. Ann Arbor, Michigan 48109, United States
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10
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Song Y, Peng J, Li K, Feng S, Qin W, Jiang J, Ma J. Control of N-nitrosodimethylamine (NDMA) formation from N,N-dimethylhydrazine compounds by ozone-based advanced oxidation processes. JOURNAL OF HAZARDOUS MATERIALS 2023; 452:131374. [PMID: 37030232 DOI: 10.1016/j.jhazmat.2023.131374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/26/2023] [Accepted: 04/04/2023] [Indexed: 06/19/2023]
Abstract
N-nitrosodimethylamine (NDMA) is formed during ozonation of model compounds with dimethylhydrazine groups, such as daminozide (DMZ) and 2-furaldehyde 2,2-dimethylhydrazone (2-F-DMH) at pH 7 with yields of 100 % and 87 %, respectively. In this study, ozone/hydrogen peroxide (O3/H2O2) and ozone/peroxymonosulfate (O3/PMS) were investigated to control NDMA formation, and O3/PMS (50-65 %) was more effective than O3/H2O2 (10-25 %) with a ratio of H2O2 or PMS to O3 of 8:1. The reaction of PMS or H2O2 to decompose ozone could not compete with the ozonation of model compound because of the high second-order rate constants of the ozonation of DMZ (5 ×105 M-1 s-1) or 2-F-DMH (1.6 ×107 M-1 s-1). The Rct value of the sulfate radical (SO4•-) showed a linear relationship with NDMA formation, indicating that SO4•- significantly contributed to its control. NDMA formation could be further controlled by injecting small quantities of ozone numerous times to minimize the dissolved ozone concentration. The effects of tannic acid, bromide and bicarbonate on NDMA formation were also investigated during ozonation, O3/H2O2, and O3/PMS processes. Bromate formation was more pronounced in the O3/PMS process than in the O3/H2O2 process. Therefore, in practical applications of O3/H2O2 or O3/PMS processes, the generation of NDMA and bromate should be detected.
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Affiliation(s)
- Yang Song
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Jianshan Peng
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Kai Li
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Sha Feng
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Wen Qin
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
| | - Jin Jiang
- Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, Guangdong 510006, China.
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
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11
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Zhang Y, Guo Y, Fang J, Guo K, Yu G, Wang Y. Characterization of UV/chlorine process for micropollutant abatement by probe compound-based kinetic models. WATER RESEARCH 2023; 237:119985. [PMID: 37098285 DOI: 10.1016/j.watres.2023.119985] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/05/2023] [Accepted: 04/18/2023] [Indexed: 05/09/2023]
Abstract
Micropollutant (MP) abatement efficiencies are critical information for optimizing water treatment process for cost-effective operations. Nevertheless, due to the vast number of MPs in real water matrices, it is infeasible to measure their abatement efficiencies individually in practical applications. In this study, a probe compound-based kinetic model was developed for generalized prediction of MP abatement in various water matrices by the ultraviolet (UV)/chlorine process. The results show that by measuring the depletion of three probe compounds (ibuprofen, primidone, and dimetridazole) spiked in the water matrix, the exposures of main reactive chlorine species (RCS including chlorine radicals (Cl•), dichloride radicals (Cl2-•) and chlorine oxide radicals (ClO•)) and hydroxyl radicals (•OH) during the UV/chlorine process could be calculated using the model. Based on the determined exposures, the abatement efficiencies of various MPs in different water matrices (e.g., surface water, groundwater, and wastewater) could generally be predicted with acceptable accuracy by the model without prior water-specific calibration. In addition, the relative contribution of UV photolysis and oxidation with active chlorine, RCS, and •OH to MP abatement could be quantitatively simulated using the model to clarify the abatement mechanism of MPs during the UV/chlorine process. The probe-based kinetic model can thus offer a useful tool to guide practical water and wastewater treatment for MP abatement and to explore the mechanism of UV/chlorine process.
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Affiliation(s)
- Yinqiao Zhang
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, 100084 Beijing, China; School of Engineering, China Pharmaceutical University, 211198 Nanjing, China
| | - Yang Guo
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, 100084 Beijing, China
| | - Jingyun Fang
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China
| | - Kaiheng Guo
- School of Environmental Science and Engineering, Sun Yat-Sen University, 510275 Guangzhou, China
| | - Gang Yu
- Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, 519087 Zhuhai, China
| | - Yujue Wang
- School of Environment, Beijing Key Laboratory for Emerging Organic Contaminants Control, State Key Joint Laboratory of Environmental Simulation and Pollution Control, Tsinghua University, 100084 Beijing, China.
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12
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Galdi SM, Szczuka A, Shin C, Mitch WA, Luthy RG. Dissolved Methane Recovery and Trace Contaminant Fate Following Mainstream Anaerobic Treatment of Municipal Wastewater. ACS ES&T ENGINEERING 2023; 3:121-130. [PMID: 36660091 PMCID: PMC9841518 DOI: 10.1021/acsestengg.2c00256] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 12/14/2022] [Accepted: 12/15/2022] [Indexed: 06/01/2023]
Abstract
Anaerobic treatment of municipal wastewater with the staged anaerobic fluidized bed membrane bioreactor (SAF-MBR) shows promise to transform secondary wastewater treatment into an energy-positive process. However, the dissolved methane in SAF-MBR effluent needs to be recovered to reach net energy positive. To recover this methane for energy generation, an air stripping system was constructed downstream of a pilot-scale SAF-MBR facility and operated for over 80 days. The process removed 98% of effluent dissolved methane, and with the addition of intermittent disinfection recovered an average of 90% of the dissolved methane. The exit gas from air-stripping comprised 1.5-2.5% methane and could be utilized by blending with biogas produced from primary solids digestion and the SAF-MBR in an on-site combustion process. The direct energy costs for air stripping methane are <1% of the energy recoverable from the dissolved methane, not accounting for siloxane or sulfide scrubbing. Only siloxanes were observed at levels impacting combustion in this study, with 1.6 mg Si/m3 present in the blended biogas and air stripping mixture. The fate of a subset of trace organic contaminants was examined across the air stripping unit to check for aerobic degradation by methanotrophs or other opportunistic aerobes. Only 1,4-dioxane and benzotriazole showed statistically significant removal among 17 compounds screened, with 0.53 ± 0.13 and 0.34 ± 0.15 fraction removal, respectively. Our results indicate that air stripping is an energy efficient and robust technology for dissolved methane removal and onsite utilization for heat and electricity generation from anaerobic treatment of municipal wastewater.
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Affiliation(s)
- Stephen M. Galdi
- Stanford
University, Stanford, California94305, United States
- NSF
Engineering Research Center for Re-inventing the Nation’s Urban
Water Infrastructure (ReNUWIt), https://www.renuwit.org/contact/
| | - Aleksandra Szczuka
- NSF
Engineering Research Center for Re-inventing the Nation’s Urban
Water Infrastructure (ReNUWIt), https://www.renuwit.org/contact/
- University
of Michigan, 1351 Beal Avenue, Ann Arbor, Michigan48019, United
States
| | - Chungheon Shin
- Stanford
University, Stanford, California94305, United States
- NSF
Engineering Research Center for Re-inventing the Nation’s Urban
Water Infrastructure (ReNUWIt), https://www.renuwit.org/contact/
| | - William A. Mitch
- Civil
and Environmental Engineering, Stanford
University, Stanford, California94305, United States
- NSF
Engineering Research Center for Re-inventing the Nation’s Urban
Water Infrastructure (ReNUWIt), https://www.renuwit.org/contact/
| | - Richard G. Luthy
- Civil
and Environmental Engineering, Stanford
University, Stanford, California94305, United States
- NSF
Engineering Research Center for Re-inventing the Nation’s Urban
Water Infrastructure (ReNUWIt), https://www.renuwit.org/contact/
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13
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Lu S, Shang C, Sun B, Xiang Y. Dominant Dissolved Oxygen-Independent Pathway to Form Hydroxyl Radicals and the Generation of Reactive Chlorine and Nitrogen Species in Breakpoint Chlorination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:150-159. [PMID: 36512687 DOI: 10.1021/acs.est.2c05540] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Due to the complexities of the interactions between ammonia, chlor(am)ine, and intermediate species such as ONOOH, the radical formation in breakpoint chlorination and the consequential removal of micropollutants remain largely unexplored. In this study, the dominant generation pathway of HO•, as a primary radical in breakpoint chlorination, was examined, and the generations of HO•, reactive chlorine species (RCS), and reactive nitrogen species (RNS) were quantitatively evaluated. A dissolved oxygen (DO)-independent pathway was verified by 18O labeling and contributed over 90% to HO• generation. The commonly believed pathway, the decomposition of ONOOH involving DO, contributed only 7% to HO• formation in breakpoint chlorination. The chlorine to nitrogen (Cl/N) ratio and pH greatly affected the generations and speciations of the reactive species. An optimum Cl/N mass ratio for HO•, Cl2•-, and RNS generations occurred at the breakpoint (i.e., Cl/N mass ratio = 9), whereas excessive free chlorine shifted the radical speciation toward ClO• at Cl/N mass ratios above the breakpoint. Basic conditions inhibited the generations of HO• and RNS but significantly promoted that of ClO•. These findings improved the fundamental understanding of the radical chemistry of breakpoint chlorination, which can be extended to estimate the degradations of micropollutants of known rate constants toward the reactive species with influences from the Cl/N ratio and pH in real-world applications.
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Affiliation(s)
- Senhao Lu
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon000, Hong Kong SAR, China
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon000, Hong Kong SAR, China
- Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon000, Hong Kong SAR, China
| | - Bo Sun
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao, Shandong26637, China
| | - Yingying Xiang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon000, Hong Kong SAR, China
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14
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Wu L, Patton SD, Liu H. Mechanisms of oxidative removal of 1,4-dioxane via free chlorine rapidly mixing into monochloramine: Implications on water treatment and reuse. JOURNAL OF HAZARDOUS MATERIALS 2022; 440:129760. [PMID: 35969953 DOI: 10.1016/j.jhazmat.2022.129760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 08/04/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
Free chlorine (HOCl) and monochloramine (NH2Cl) are two of the most commonly used water disinfectants in water treatment; however, the capability of rapid mixing of HOCl into NH2Cl to induce oxidative reactions for efficient removal of contaminants remains largely unknown. In this study, 1,4-dioxane (1,4-D) removal was quantified during the rapid mixing of HOCl into NH2Cl, to evaluate the effects of solution pH and HOCl-to-NH2Cl ratio, and to identify mechanisms by which reactive species are generated in the system. Results showed that the highest 1,4-D removal was observed at the near-neutral pH of 6 with the HOCl-to-NH2Cl molar ratio of 1. Hydroxyl radical (HO•) contributed to 60-70 % of 1,4-D degradation and its generation was initiated by the hydrolytic decay of NH2Cl and NHCl2 upon HOCl addition to NH2Cl with rapid mixing, and subsequent transformation of peroxynitrite (ONOO-) and peroxynitrous acid (ONOOH). The results also confirmed that the presence of dissolved oxygen was required to form ONOO-/ONOOH, and ONOO- was a crucial precursor for reactive radical generation. These findings provide insight into the reaction mechanism associated with the system of rapidly mixed HOCl into NH2Cl with the potential optimization and application for efficient trace organics removal in water treatment and reuse.
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Affiliation(s)
- Liang Wu
- Environmental Toxicology Program, University of California, Riverside, CA 92521, USA; Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA
| | - Samuel D Patton
- Environmental Toxicology Program, University of California, Riverside, CA 92521, USA; Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA
| | - Haizhou Liu
- Environmental Toxicology Program, University of California, Riverside, CA 92521, USA; Department of Chemical and Environmental Engineering, University of California, Riverside, CA 92521, USA.
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15
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Fan J, Deng C, Rao Y. Photodegradation of N-nitrosodimethylamine under 365 nm Light Emitting Diode Irradiation. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2022; 94:e10787. [PMID: 36082624 DOI: 10.1002/wer.10787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 08/12/2022] [Accepted: 08/21/2022] [Indexed: 06/15/2023]
Abstract
The photodegradation of NDMA has been extensively investigated under the irradiation of low-pressure or medium-pressure Hg lamps and xenon lamp. However, NDMA photolysis remains unknown under 365 nm ultraviolet light-emitting diode (UV-LED) irradiation. This study conducted a comprehensive investigation on NDMA photodegradation by 365 nm UV-LED illumination. The quantum yield of NDMA photolysis under 365 nm UV-LED irradiation was determined to be 0.0312 ± 0.0047. The influence of pH on NDMA photodegradation was found to be wavelength dependent. Compared with distilled and deionized water (DDW), tap water inhibited NDMA photodegradation, but secondary wastewater effluent did not. Based on the quantification of NDMA photolysis products and pH influence, the photooxidation of the excited NDMA in the nonprotonated form was proposed to be a major pathway for NDMA photodegradation under the irradiation of UV-LED lamp at 365 nm. This study further enhances our knowledge on NDMA photodegradation. PRACTITIONER POINTS: Quantum yield of NDMA photolysis at 365 nm was determined to be 0.0312 ± 0.0047. The influence of pH on NDMA photodegradation was wavelength dependent. NDMA photodegradation was inhibited in tap water compared with that in DDW. NDMA photodegradation in SWE was similar to that in DDW. Excited nonprotonated NDMA photooxidation is a major degradation pathway.
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Affiliation(s)
- Jiahui Fan
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, China
| | - Cun Deng
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, China
| | - Yongfang Rao
- Department of Environmental Science and Engineering, Xi'an Jiaotong University, Xi'an, China
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16
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Hua Z, Li J, Zhou Z, Zheng S, Zhang Y, Fang J. Exploring Pathways and Mechanisms for Dichloroacetonitrile Formation from Typical Amino Compounds during UV/Chlorine Treatment. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:9712-9721. [PMID: 35703371 DOI: 10.1021/acs.est.2c01495] [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] [Indexed: 06/15/2023]
Abstract
The formation of disinfection byproducts (DBPs) during UV/chlorine treatment, especially nitrogenous DBPs, is not well understood. This study investigated the formation mechanisms for dichloroacetonitrile (DCAN) from typical amino compounds during UV/chlorine treatment. Compared to chlorination, the yields of DCAN increase by 88-240% during UV/chlorine treatment from real waters, while the yields of DCAN from amino compounds increase by 3.3-5724 times. Amino compounds with electron-withdrawing side chains show much higher DCAN formation than those with electron-donating side chains. Phenylethylamine, l- phenylalanine, and l-phenylalanyl-l-phenylalanine were selected to represent amines, amino acids, and peptides, respectively, to investigate the formation pathways for DCAN during UV/chlorine treatment. First, chlorination of amines, amino acids, and peptides rapidly forms N-chloramines via chlorine substitution. Then, UV photolysis but not radicals promotes the transformation from N-chloramines to N-chloroaldimines and then to phenylacetonitrile, with yields of 5.4, 51.0, and 19.8% from chlorinated phenylethylamine, l-phenylalanine, and l-phenylalanyl-l-phenylalanine to phenylacetonitrile, respectively. Finally, phenylacetonitrile is transformed to DCAN with conversion ratios of 14.2-25.6%, which is attributed to radical oxidation, as indicated by scavenging experiments and density functional theory calculations. This study elucidates the pathways and mechanisms for DCAN formation from typical amino compounds during UV/chlorine treatment.
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Affiliation(s)
- Zhechao Hua
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Junfang Li
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zhihong Zhou
- Guangzhou Ecological Environmental Monitoring Center, Guangzhou 510006, China
| | - Shanshan Zheng
- Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yifei Zhang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
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17
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Song Y, Feng S, Qin W, Li J, Guan C, Zhou Y, Gao Y, Zhang Z, Jiang J. Formation mechanism and control strategies of N-nitrosodimethylamine (NDMA) formation during ozonation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 823:153679. [PMID: 35131246 DOI: 10.1016/j.scitotenv.2022.153679] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 01/06/2022] [Accepted: 01/31/2022] [Indexed: 06/14/2023]
Abstract
This review summarizes major findings over the last decade related to N-nitrosodimethylamine (NDMA) formed upon ozonation, which was regarded as highly toxic and carcinogenic disinfection by-products. The reaction kinetics, chemical yields and mechanisms were assessed for the ozonation of potential precursors including dimethylamine (DMA), N,N-dimethylsulfamide, hydrazines, N-containing water and wastewater polymers, dyes containing a dimethylamino function, N-functionalized carbon nanotubes, guanidine, and phenylurea. The effects of bromide on the NDMA formation during ozonation of different types of precursors were also discussed. The mechanism for NDMA formation during ozonation of DMA was re-summarized and new perspectives were proposed to assess on this mechanism. Effect of hydroxyl radicals (•OH) on NDMA formation during ozonation was also discussed due to the noticeable oxidation of NDMA by •OH. Surrogate parameters including nitrate formation and UV254 after ozonation may be useful parameters to estimate NDMA formation for practical application. The strategies for NDMA formation control were proposed through improving the ozonation process such as ozone/hydrogen peroxide, ozone/peroxymonosulfate and catalytic ozonation process based on membrane pores aeration (MEMBRO3X).
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Affiliation(s)
- Yang Song
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Sha Feng
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Wen Qin
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, Guangdong, China
| | - Juan Li
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Chaoting Guan
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Yang Zhou
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Yuan Gao
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, 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, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Jin Jiang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China.
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18
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Chuang YH, Shi HJ. UV/chlorinated cyanurates as an emerging advanced oxidation process for drinking water and potable reuse treatments. WATER RESEARCH 2022; 211:118075. [PMID: 35066259 DOI: 10.1016/j.watres.2022.118075] [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: 11/01/2021] [Revised: 01/06/2022] [Accepted: 01/13/2022] [Indexed: 06/14/2023]
Abstract
Chlorinated cyanurates, prepared by application of hypochlorite to cyanuric acid at different ratios, have been commonly employed for disinfection. Combining UV with chlorinated cyanurates (UV/Cl-cyanurates) can be a novel and effective advanced oxidation process (AOP) because (1) Cl-cyanurates structurally resemble chlorinated amides that feature low reactivity with radicals, and (2) Cl-cyanurates, which bear multiple -Cl, may exhibit high molar absorptivity at 254 nm due to red-shifting absorption. Those chemiphysical properties of Cl-cyanurates may facilitate oxidant photolysis rate and lower radical scavenging rates in an AOP, thereby increasing steady-state concentrations of radicals. In this study, UV spectra measured for Cl-cyanurates highlighted molar absorptivities at 254 nm (∼200 M-1cm-1) much higher than free chlorine or H2O2, while k•OH determined using competition kinetics suggests low •OH reactivity (<1.95 × 107 M-1s-1) for Cl-cyanurates. Photolysis of Cl-cyanurates forms •Cl (i.e., Cl-N cleavage), and •Cl converts to •OH; formation of •OH during a UV/Cl-cyanurates AOP was evaluated using terephthalate as a probe compound. Experiments systematically investigated the effects of pH, Cl2 dosage, and cyanuric concentration (three key factors affecting the equilibrium concentrations of chlorinated-cynaurate species) on the efficacy of removing three indicator contaminants by UV/Cl-cyanurates AOP. UV/Cl-cyanurates AOP conducted in phosphate buffers or authentic surface waters highlighted efficiencies up to 170% higher than UV/Cl2 AOP at neutral pH when the same dosage of oxidants was employed, and the presence of certain levels of background ammonia or chloramines further enhanced its performance. Transformation of cyanuric acid or Cl-cyanurates by reacting with radicals during a UV/Cl-cyanurates AOP treatment was minimum. Toxicity assay indicated that UV/Cl-cyanurates AOP treated water was comparable or less toxicity than UV/H2O2 or UV/Cl2 AOP treated water, and the initial cost estimate indicates UV/Cl-cyanurates AOP is potentially a cost-effective alternative AOP.
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Affiliation(s)
- Yi-Hsueh Chuang
- Institute of Environmental Engineering, National Yang Ming Chiao Tung University, 1001 University Rd., Hsinchu 30010, Taiwan.
| | - Hong-Jia Shi
- Institute of Environmental Engineering, National Yang Ming Chiao Tung University, 1001 University Rd., Hsinchu 30010, Taiwan
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19
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Cao Z, Yu X, Zheng Y, Aghdam E, Sun B, Song M, Wang A, Han J, Zhang J. Micropollutant abatement by the UV/chloramine process in potable water reuse: A review. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127341. [PMID: 34634702 DOI: 10.1016/j.jhazmat.2021.127341] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 06/13/2023]
Abstract
The need in using reclaimed water increased significantly to address the water shortage and its continuing quality deterioration in sustaining societal development. Degrading micropollutants in wastewater treatment plant effluents is one of the most important tasks in supplying safe drinking water, which is often achieved by full advanced treatment technologies (FATs), including reverse osmosis (RO) and the UV-based advanced oxidation process (AOP). As an emerging AOP, UV/chloramine process shows many noteworthy advantages in the scenario of potable water reuse, including membrane biological fouling control by chloramine, producing highly reactive radicals (e.g., Cl•, HO•, Cl2•-, and reactive nitrogen-containing species) to degrade the RO permeated pollutants, and acting as long-lasting disinfectant in the potable water distribution system. In addition, chloramine is often designedly produced by taking advantage of the ammonia in source. Thus, UV/chloramine processes gather much attention from researcher and published papers on UV/chloramine process have drastically increased since 2016, which were thoroughly reviewed in this paper. The fundamentals of chloramine photolysis, including the photolysis kinetics, the quantum yield, the generation and transformation of radicals and the final products, were scrutinized. Further, the impacts of reaction conditions such as pH, chloramine dosage and water matrix on the degradation of micropollutants by the UV/chloramine process are discussed. Moreover, the formation potential of disinfection by-products is debated. The opportunity of application of the UV/chloramine process in real-world practice is also presented, emphasizing the need for extensive efforts to remove currently prevalent knowledge roadblocks.
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Affiliation(s)
- Zhenfeng Cao
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Ximing Yu
- Taiwei Energy Group Co., Ltd., Jinan, Shandong 250001, PR China
| | - Yuzhen Zheng
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Ehsan Aghdam
- Department of Civil and Environmental Engineering, the Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Bo Sun
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao, Shandong 266237, PR China; Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China.
| | - Mingming Song
- School of Environmental Science & Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong 250353, PR China
| | - Aijie Wang
- Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China; School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, PR China
| | - Jinglong Han
- School of Civil & Environmental Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, PR China
| | - Jian Zhang
- Shandong Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science & Engineering, Shandong University, Qingdao, Shandong 266237, PR China.
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20
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Guo K, Wu Z, Chen C, Fang J. UV/Chlorine Process: An Efficient Advanced Oxidation Process with Multiple Radicals and Functions in Water Treatment. Acc Chem Res 2022; 55:286-297. [PMID: 35025201 DOI: 10.1021/acs.accounts.1c00269] [Citation(s) in RCA: 96] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Because of the deterioration of global water quality, the occurrence of chemical and microbial contaminants in water raises serious concerns for the health of the population. Identifying and developing effective and environmentally friendly water treatment technologies are critical to obtain clean water. Among the various technologies for the purification of water, ultraviolet photolysis of chlorine (UV/chlorine), an emerging advanced oxidation process (AOP), has multiple functions for the control of contaminants via the production of hydroxyl radicals (HO·) and reactive chlorine species (RCS), such as Cl·, ClO·, and Cl2·-.This Account centers around the radical chemistry of RCS and HO· in different water matrices and their roles and mechanisms in the abatement of contaminants. The concentrations of Cl·, ClO·, and Cl2·- are comparable to or higher than those of HO· (10-14 to 10-13 M). The reactivities of RCS are more selective than HO· with a broader range of second-order rate constants (k). The k values of Cl· toward most aromatics are higher or similar as compared to those of HO·, while those of Cl2·- and ClO· are less reactive but more selective toward aromatics containing electron-donating functional groups. Their major reaction mechanisms with Cl· are electron transfer and addition, while those with ClO· and Cl2·- primarily involve electron transfer. As for aliphatics, their reactivities with both HO· and RCS are much lower than those of aromatics. The reaction mechanisms for most of them with Cl· and Cl2·- are hydrogen abstraction, except for olefins, which are addition. In addition, RCS greatly contribute to the inactivation of microbial contaminants.Toward future application, the UV/chlorine process has both pros and cons. Compared with the traditional HO·-based AOP of UV/H2O2, UV/chlorine is more efficient and energy-saving for oxidation and disinfection, and its efficiency is less affected by water matrix components. However, the formation of toxic byproducts in UV/chlorine limits its application scenarios. In dissolved organic matter (DOM)-rich water, the formation of halogenated byproducts is enhanced in UV/chlorine. In the presence of ammonia, reactive nitrogen species (RNS) (e.g., ·NO and ·NO2) are involved, and highly toxic nitro(so) products such as nitro(so)-phenolics and N-nitrosodimethylamine are generated. For a niche application, the UV/chlorine process is recommended to be utilized in water with low levels of DOM and ammonia.Strategies should be developed to make full use of highly reactive species (RCS and HO·) for the abatement of target contaminants and to reduce the formation of toxic byproducts. For example, the UV/chlorine process can be used in tandem with other treatments to create multiple barriers for the production of safe water. In addition, halogen radicals are very important in ecosystems as well as other areas such as medical therapy and organic synthesis. UV/chlorine is the most efficient homogeneous system to generate halogen radicals, and thus it provides a perfect system to investigate the fates of halogen radicals for interdisciplinary research.
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Affiliation(s)
- Kaiheng Guo
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Zihao Wu
- Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai Zhuhai 519087, P. R. China
| | - Chunyan Chen
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
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21
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Wang S, Liu H, Gu J, Zhang M, Liu Y. Towards carbon neutrality and water sustainability: An integrated anaerobic fixed-film MBR-reverse osmosis-chlorination process for municipal wastewater reclamation. CHEMOSPHERE 2022; 287:132060. [PMID: 34507145 DOI: 10.1016/j.chemosphere.2021.132060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 08/13/2021] [Accepted: 08/26/2021] [Indexed: 06/13/2023]
Abstract
Freshwater resilience is facing to an increasing challenge, while carbon neutral wastewater reclamation has been put onto agenda in more and more countries. The activated sludge-microfiltration (MF)-reverse osmosis (RO) process has been currently adopted for reclamation of municipal wastewater to high-grade product water (e.g. NEWater). However, the conventional activated sludge (CAS) unit in this process has the drawbacks of excessive sludge generation, high energy consumption, greenhouse gases (GHGs) emissions etc. To address these emerging issues, an integrated anaerobic fixed-film membrane bioreactor (AnfMBR)-RO-chlorination process was developed in this study. Results showed that about 99.9% of COD, 99.3% of phosphate and 95.3% of NH4+-N were removed in the AnfMBR-RO process, while breakpoint chlorination served as a polishing step when the NH4+-N concentration in RO permeate exceeded the typical NH4+-N concentration (e.g. 1 mg/L) of NEWater. The net energy consumption and total GHG emissions in the proposed integrated process were estimated to be 0.33 kWh/m3 and 310.2 g CO2e/m3 influent wastewater treated, respectively, which were 64% and 74% less than those in the current municipal wastewater reclamation process. Consequently, this study offers an alternative path to bring municipal wastewater reclamation one step closer to carbon neutrality and water sustainability.
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Affiliation(s)
- Siyu Wang
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore; Interdisciplinary Graduate School, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
| | - Hang Liu
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore
| | - Jun Gu
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore
| | - Meng Zhang
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore
| | - Yu Liu
- Advanced Environmental Biotechnology Centre, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore; School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
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22
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Seid MG, Lee C, Cho K, Hong SW. Degradation of ranitidine and changes in N-nitrosodimethylamine formation potential by advanced oxidation processes: Role of oxidant speciation and water matrix. WATER RESEARCH 2021; 203:117495. [PMID: 34388496 DOI: 10.1016/j.watres.2021.117495] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/21/2021] [Accepted: 07/28/2021] [Indexed: 06/13/2023]
Abstract
This study investigated the effects of thirteen (photo/electro) chemical oxidation processes on the formation potential (FP) of N-nitrosodimethylamine (NDMA) during the chloramination of ranitidine in reverse osmosis (RO) permeate and brine. The NDMA-FP varied significantly depending on the pretreatment process, initial pH, and water matrix types. At higher initial pH values (> 7.0), most pretreatments did not reduce the NDMA-FP, presumably because few radical species and more chloramine-reactive byproducts were generated. At pH < 7.0, however, electrochemical oxidation assisted by chloride and Fe2+/H2O2, catalytic wet peroxide oxidation and peroxydisulfate-induced pretreatments removed up to 85% of NDMA-FP in the RO brine. Ultraviolet (UV) irradiation or prechlorination alone did not reduce the NDMA-FP effectively, but combined UV/chlorine treatment effectively reduced the NDMA-FP. In contrast, after UV irradiation (2.1 mW cm-2 for 0.5 h) in the presence of H2O2 and chloramine, NDMA formation increased substantially (up to 26%) during the post-chloramination of the RO permeate. Mass spectrometric analysis and structural elucidation of the oxidation byproducts indicated that compared with the reactive nitrogen species generated by UV/NH2Cl, sulfate radicals and (photo/electro)chemically generated reactive chlorine species were more promising for minimizing NDMA-FP. Unlike, the hemolytic •OH driven by UV/H2O2, the •OH from Fe(IV)-assisted pretreatments showed a significant synergistic effect on NDMA-FP reduction. Overall, the results suggest the need for a careful assessment of the type of radical species to be used for treating an RO water system containing amine-functionalized compounds.
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Affiliation(s)
- Mingizem Gashaw Seid
- Water Cycle Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Division of Energy and Environment Technology, KIST-School, University of Science and Technology, Seoul 02792, Republic of Korea
| | - Changha Lee
- School of Chemical and Biological Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Kangwoo Cho
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang 790-784, Republic of Korea; Institute for Convergence Research and Education in Advanced Technology (I-CREATE), Yonsei University International Campus, Incheon 21983, Republic of Korea.
| | - Seok Won Hong
- Water Cycle Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea; Division of Energy and Environment Technology, KIST-School, University of Science and Technology, Seoul 02792, Republic of Korea.
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23
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Wang L, Ye C, Guo L, Chen C, Kong X, Chen Y, Shu L, Wang P, Yu X, Fang J. Assessment of the UV/Chlorine Process in the Disinfection of Pseudomonas aeruginosa: Efficiency and Mechanism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:9221-9230. [PMID: 34138551 DOI: 10.1021/acs.est.1c00645] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
UV irradiation and chlorination have been widely used for water disinfection. However, there are some limitations, such as the risk of generating viable but nonculturable bacteria and bacteria reactivation when using UV irradiation or chlorination alone. This study comprehensively evaluated the feasibility of the UV/chlorine process in drinking water disinfection, and Pseudomonas aeruginosa was selected as the target microorganism. The number of culturable cells was effectively reduced by more than 5 orders of magnitude (5-log10) after UV, chlorine, and UV/chlorine treatments. However, intact and VBNC cells were detected at 103 to 104 cells/mL after UV and chlorine treatments, whereas they were undetectable after UV/chlorine treatment due to the primary contribution of reactive chlorine species (Cl•, Cl2•-, and ClO•). After UV/chlorine treatment, the metabolic activity determined using single cell Raman spectroscopy was much lower than that after UV. The level of toxic opr gene in P. aeruginosa decreased by more than 99% after UV/chlorine treatment. Importantly, bacterial dark reactivation was completely suppressed by UV/chlorine treatment but not UV or chlorination. This study suggests that the UV/chlorine treatment can completely damage bacteria and is promising for pathogen inactivation to overcome the limitations of UV and chlorine treatments alone.
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Affiliation(s)
- Liping Wang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Chengsong Ye
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, P. R. China
| | - Lizheng Guo
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, P. R. China
| | - Chunyan Chen
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Xiujuan Kong
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Yaoqing Chen
- School of Public Health, Shenzhen, Sun Yat-Sen University, Shenzhen 510000, P. R. China
| | - Longfei Shu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Peng Wang
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Kowloon 999077, Hong Kong, P.R. China
| | - Xin Yu
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, P. R. China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
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