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Yu M, Qian Y, Ni M, Wang Z, Zhang P. Algae removal and algal organic matter chemistry modulated by KMnO 4-PAC in simulated karst water. CHEMOSPHERE 2024; 354:141733. [PMID: 38513953 DOI: 10.1016/j.chemosphere.2024.141733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 03/05/2024] [Accepted: 03/14/2024] [Indexed: 03/23/2024]
Abstract
In this study, we examined the modulation of algae removal and algal organic matter (AOM) chemistry by potassium permanganate and poly-aluminum chloride (KMnO4-PAC) in simulated karst water. Specifically, we verified the compositional changes of AOM sourcing from Chlorella sp. and Pseudanabaena sp. in response to the presence of divalent ions (Ca2+ and Mg2+). Aromatic protein and soluble microbial products were identified as the primary AOM components. Divalent ions accelerated dissolved organic carbon (DOC) and UV254 removal, particularly with Pseudanabaena sp. greater than Chlorella sp. (P < 0.05). Surface morphology analysis manifested that the removal of filamentous Pseudanabaena sp. was more feasible in comparison to globular Chlorella sp.. Our results highlight the significance of divalent ions in governing chemical behaviors and subsequent removal of both algae and AOM. This study upscales the understanding of the interactions among divalent ions, algae and AOM during preoxidation and coagulation process in algae-laden karst water.
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Affiliation(s)
- Mengxin Yu
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Yu Qian
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang, 550025, China
| | - Maofei Ni
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang, 550025, China.
| | - Zhikang Wang
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang, 550025, China; Guiyang Institute of Information Science and Technology, Guiyang, 550025, China.
| | - Ping Zhang
- College of Eco-Environmental Engineering, Guizhou Minzu University, Guiyang, 550025, China
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2
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Liu M, Wu N, Li X, Zhang S, Sharma VK, Ajarem JS, Allam AA, Qu R. Insights into manganese(VII) enhanced oxidation of benzophenone-8 by ferrate(VI): Mechanism and transformation products. WATER RESEARCH 2023; 238:120034. [PMID: 37150061 DOI: 10.1016/j.watres.2023.120034] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 03/25/2023] [Accepted: 05/01/2023] [Indexed: 05/09/2023]
Abstract
Benzophenones (BPs) are commonly used as UV filters in cosmetics and plastics products and are potentially toxic to the environment. This paper presents kinetics and products of BPs oxidation by ferrate(VI) (FeO42-, Fe(VI)) promoted by permanganate (Mn(VII)) . Degradation of 10.0 µM 2,2'-dihydroxy-4-methoxybenzophenone (BP-8)were determined under different experimental conditions ([Mn(VII)] = 0.5-1.5 µM, [Fe(VI)] = 50-150 µM, and pH = 7.0-10.0). The addition of Mn(VII) traces to Fe(VI)-BP-8 solution enhanced kinetics and efficiency of the removal. Similar enhanced removals were also seen for other BPs (BP-1, BP-3, and BP-4) under optimized conditions. The second-order rate constants (k, M-1s-1) of the degradation of BPs showed positive relationship with the energy of the highest occupied orbital (EHOMO). The possible interaction between Mn(VII) and BP-8 and the enhanced generation of Fe(V)/Fe(IV) and •OH was proposed to facilitate the oxidation of the target benzophenone, supported by in-situ electrochemical measurements, theoretical calculations and reactive species quenching experiments. Thirteen oxidation products of BP-8 suggested hydroxylation, bond breaking, polymerization and carboxylation steps in the oxidation. Toxicity assessments by ECOSAR program showed that the oxidized intermediate products posed a tapering ecological risk during the degradation process. Overall, the addition of Mn(VII) could improve the oxidation efficiency of Fe(VI).
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Affiliation(s)
- Mingzhu Liu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing, 210023, P. R. China
| | - Nannan Wu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing, 210023, P. R. China
| | - Xiaoyu Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing, 210023, P. R. China
| | - ShengNan Zhang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing, 210023, P. R. China
| | - Virender K Sharma
- Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, TX, 77843, United States.
| | - Jamaan S Ajarem
- Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
| | - Ahmed A Allam
- Department of Zoology, Faculty of Science, Beni Suef University, Beni Suef, 65211, Egypt
| | - Ruijuan Qu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Jiangsu Nanjing, 210023, P. R. China.
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Li J, Song Y, Jiang J, Yang T, Cao Y. Oxidative treatment of NOM by selective oxidants in drinking water treatment and its impact on DBP formation in postchlorination. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:159908. [PMID: 36336058 DOI: 10.1016/j.scitotenv.2022.159908] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 10/26/2022] [Accepted: 10/29/2022] [Indexed: 06/16/2023]
Abstract
Natural organic matter (NOM), as a ubiquitous component in aqueous environments, has raised continuous scientific concerns due to its role as an organic precursor to disinfection by-products (DBPs) in the subsequent chlorination process. Selective oxidants, including ozone (O3), chlorine dioxide (ClO2), permanganate (Mn(VII)), and ferrate (Fe(VI)) are widely used in the preoxidation stage in drinking water treatment. The selective reactivity of those oxidants toward NOM is expected to alternate NOM properties and consequently DBP formation in postchlorination. Despite extensive studies on the interactions of NOM with selective oxidants, there is currently a lack of an overview of this area. To fill this gap, this study presents the current knowledge of the modification of NOM properties by selective oxidants and its impact on DBP formation in postchlorination. The NOM property changes in three aspects, including bulk property (e.g., total organic carbon, ultraviolet absorbance), fractional constituent (e.g., molecular size, hydrophilicity/hydrophobicity), and elemental composition (e.g., functional group) by the four selective oxidants (i.e., O3, ClO2, Mn(VII), and Fe(VI)) were discussed. Thereafter, the impacts of alteration of NOM properties by those selective oxidants on DBP formation in the subsequent chlorination were summarized, wherein the key influencing factors were discussed. Finally, the future perspectives in this area were forwarded, which highlighted the significance of process optimization, the attention to the less studied but more toxic DBPs, and the need for the identification of unknown DBPs. This review presented a state-of-the-art knowledge pool of the fate of NOM in oxidation and chlorination processes, promoted our understanding of the relationship between NOM properties and DBP formation, and identified further research needs in this area.
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Affiliation(s)
- Juan Li
- Advanced Interdisciplinary Institute of Environment and Ecology, Beijing Normal University, Zhu Hai 519087, China.
| | - Yang Song
- School of Civil and Transportation Engineering, 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
| | - Tao Yang
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Ying Cao
- School of Environment, Harbin Institute of Technology, Harbin 150090, China
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Zheng ZX, Lin YL, Fang RF, Zhou XY, Liu Z, Dong ZY, Zhang TY, Xu B. Removal of algae and algogenic odor compounds via combined pre-chlorination and powdered activated carbon adsorption for source water pretreatment. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2022.122365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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5
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Luo Y, Liu C, He S. Synthesis and characterization of a novel magnetic resin (m-MAR resin) and its removal performance for alkaline amino acids. ENVIRONMENTAL RESEARCH 2022; 214:114067. [PMID: 35963319 DOI: 10.1016/j.envres.2022.114067] [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: 05/10/2022] [Revised: 07/23/2022] [Accepted: 08/04/2022] [Indexed: 06/15/2023]
Abstract
Alkaline amino acids as dissolved organic nitrogen (DON) have raised much concern in drinking water treatment due to poor removal in conventional treatment process and high potential for nitrogenous disinfection by-products (N-DBPs). This work was intended to devise a new magnetic adsorption resin (noted as m-MAR resin) for the efficient reduction of alkaline amino acids and explore the application potential of combined MIEX and m-MAR resins. The distribution and composition of DON and amino acids was clarified for different water sources in Lake Taihu basin, in which alkaline amino acids accounted for a higher proportion. The removal of different nitrogenous organics by MIEX resin was also examined, where the resin was effective in removing phycocyanin (65.6%) and glutamic acid (74.2%), reducing the generation of disinfection by-products (DBPs). The m-MAR resin was manufactured and characterized to cope with alkaline amino acids, and batch experiments were undertaken to investigate its adsorption behaviors on histidine and arginine under different operating conditions. The maximal adsorption capacities of arginine and histidine onto m-MAR resin were 2.84 mg/g and 1.62 mg/g, respectively, which was better than MIEX resin. The removal mechanism of the two basic amino acids by m-MAR resin was mainly due to the hydrogen bonding and the acid-base reaction. Moreover, the reusability of the m-MAR resin was elucidated after six successive adsorption-desorption cycles. Finally, the effectiveness of combined MIEX and m-MAR resin in treating DON derived from Microcystis aeruginosa reached 35.2% and the DON concentration in Lake Taihu could be reduced from 0.56 to 0.16 mg/L, which simultaneously decreased the generation potential of N-DBPs. The enhancement of coagulation by the combined process of m-MIER and m-MAR as pretreatment was estimated.
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Affiliation(s)
- Yuye Luo
- College of Environment, Hohai University, Nanjing, 210098, China
| | - Cheng Liu
- Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education, Hohai University, Nanjing, 210098, China; College of Environment, Hohai University, Nanjing, 210098, China.
| | - Siyuan He
- College of Environment, Hohai University, Nanjing, 210098, China
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Mondal P, Singh P, Morgan D, Bose A, Sen K. Ni-Sinapic Acid Nanocomposite in the Selective Sensing of Permanganate ions. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.114458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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7
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Ma B, Liu Y, Lin H, Fan H, Lu C, Zhao K, Qi J. A pilot-scale study of the integrated floc-ultrafiltration membrane-based drinking water treatment process. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 830:154809. [PMID: 35341872 DOI: 10.1016/j.scitotenv.2022.154809] [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: 10/01/2021] [Revised: 02/18/2022] [Accepted: 03/21/2022] [Indexed: 06/14/2023]
Abstract
Although applications of the integrated ultrafiltration (UF) membrane have been investigated for years, most studies have been conducted at the lab scale. Here, a case study on the integrated Fe-based floc-UF process was presented. To enhance membrane performance, both pre-filtration (bag filter) and pre-oxidation were used as pretreatments to remove particles and inhibit the development of microorganisms. Results showed that the integrated process operated stably with pre-treatments, and the UF membrane fouling behavior could be divided into three different phases: slow increase rate (phase I), medium increase rate (phase II), and fast increase rate (phase III). In comparison to those in phases II and III, both natural organic matters and colloids were the main membrane fouling mechanisms during phase I, as the pollutants were not successfully removed by flocs initially. With the continuous injection of flocs, a loose cake layer became the main fouling mechanism during phase II, resulting in the deterioration of membrane fouling. During phase III, however, microorganisms (e.g., Proteobacteria) were inevitably nourished within the cake layer and played an important role in aggravating the degree of membrane fouling. During this integrated membrane-based process, several operating factors, including floc concentration, sludge discharge frequency, and the aeration rate during backwashing, played important roles in determining membrane performance. In addition, except for oxygen consumption, all the effluent quality parameters met the drinking water criteria followed in China (GB5749-2006).
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Affiliation(s)
- Baiwen Ma
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; Lehrstuhl für Technische Chemie II, Universität Duisburg-Essen, Essen 45117, Germany.
| | - Yansong Liu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; College of New Energy and Environment, Jilin University, Changchun, 130021, Jilin, China
| | - Hui Lin
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hongwei Fan
- College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Chaojie Lu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kai Zhao
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jing Qi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
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8
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Dong H, Zhang H, Wang Y, Qiang Z, Yang M. Disinfection by-product (DBP) research in China: Are we on the track? J Environ Sci (China) 2021; 110:99-110. [PMID: 34593199 DOI: 10.1016/j.jes.2021.03.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 03/10/2021] [Indexed: 06/13/2023]
Abstract
Disinfection by-products (DBPs) formed during water disinfection has drawn significant public concern due to its toxicity. Since the first discovery of the trihalomethanes in 1974, continued effort has been devoted on DBPs worldwide to investigate the formation mechanism, levels, toxicity and control measures in drinking water. This review summarizes the main achievements on DBP research in China, which included: (1) the investigation of known DBP occurrence in drinking water of China; (2) the enhanced removal of DBP precursor by water treatment process; (3) the disinfection optimization to minimize DBP formation; and (4) the identification of unknown DBPs in drinking water. Although the research of DBPs in China cover the whole formation process of DBPs, there is still a challenge in effectively controlling the drinking water quality risk induced by DBPs, an integrated research framework including chemistry, toxicology, engineering, and epidemiology is especially crucial.
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Affiliation(s)
- Huiyu Dong
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Haifeng Zhang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yan Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhimin Qiang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Min Yang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Xu Z, Huang W, Xie H, Feng X, Wang S, Song H, Xiong J, Mailhot G. Co-adsorption and interaction mechanism of cadmium and sulfamethazine onto activated carbon surface. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126540] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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Bibliometric review of research trends on disinfection by-products in drinking water during 1975–2018. Sep Purif Technol 2020. [DOI: 10.1016/j.seppur.2020.116741] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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11
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Liu Z, Lin YL, Chu WH, Xu B, Zhang TY, Hu CY, Cao TC, Gao NY, Dong CD. Comparison of different disinfection processes for controlling disinfection by-product formation in rainwater. JOURNAL OF HAZARDOUS MATERIALS 2020; 385:121618. [PMID: 31791866 DOI: 10.1016/j.jhazmat.2019.121618] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/28/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
With increasing shortage of clean water, rainwater has been considered as a precious alternative drinking water source. The processes applied to rainwater treatment are responsible for the safety of drinking water. Therefore, we systematically compared different disinfection processes to evaluate the control of disinfection by-product (DBP) formation and integrated cyto- and genotoxicity of the treated rainwater for the first time. The evaluated disinfection processes included chlorination and chloramination, pre-oxidation by potassium permanganate (KMnO4) and potassium ferrate (K2FeO4), ultraviolet/hydrogen peroxide (UV/H2O2), and ultraviolet/persulfate (UV/PS) processes. The results revealed that chloramination was effective for controlling the formation of carbonaceous DBPs (C-DBPs), but not nitrogenous DBPs (N-DBPs). Compared to KMnO4 pre-oxidation, better reduction of almost all DBPs was observed during K2FeO4 pre-oxidation. According to the calculation of cytotoxicity index (CTI) and genotoxicity index (GTI), cyto- and genotoxicity of the samples decreased obviously at the dosage of ≥ 2.0 mg/L KMnO4 and K2FeO4. The control of the cyto- and genotoxicity of the formed DBPs from the two UV-related AOPs was more effective at the dosage of ≥ 1.0 mM PS and ≥ 5.0 mM H2O2. Moreover, UV/PS was much more powerful to alter the structure of DBP precursors in rainwater.
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Affiliation(s)
- Zhi Liu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Yi-Li Lin
- Department of Safety, Health and Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 824, Taiwan, ROC
| | - Wen-Hai Chu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Bin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
| | - Tian-Yang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Chen-Yan Hu
- College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, PR China
| | - Tong-Cheng Cao
- School of Chemical Science and Engineering, Key Laboratory of Road and Traffic Engineering of Ministry of Education, Tongji University, Shanghai 200092, PR China
| | - Nai-Yun Gao
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Cheng-Di Dong
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan, ROC
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Hua Z, Kong X, Hou S, Zou S, Xu X, Huang H, Fang J. DBP alteration from NOM and model compounds after UV/persulfate treatment with post chlorination. WATER RESEARCH 2019; 158:237-245. [PMID: 31039453 DOI: 10.1016/j.watres.2019.04.030] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 04/10/2019] [Accepted: 04/13/2019] [Indexed: 06/09/2023]
Abstract
The UV/persulfate process is an effective advanced oxidation process (AOP) for the abatement of a variety of micropollutants via producing sulfate radicals (SO4•-). However, when this technology is used to reduce target pollutants, the precursors of disinfection byproducts (DBPs), such as natural organic matter (NOM) and organic nitrogen compounds, can be altered. This study systematically investigated the DBP formation from NOM and five model compounds after UV/H2O2 and UV/persulfate treatments followed with 24 h chlorination. Compared to chlorination alone, the yields of trichloromethane (TCM) and dichloroacetonitrile (DCAN) from NOM decreased by 50% and 54%, respectively, after UV/persulfate treatment followed with chlorination, whereas those of chloral hydrate (CH), 1,1,1-trichloropropanone (1,1,1-TCP) and trichloronitromethane (TCNM) increased by 217%, 136%, and 153%, respectively. The effect of UV/H2O2 treatment on DBP formation shared a similar trend to that of UV/persulfate treatment, but the DBP formation was higher from the former. As the UV/persulfate treatment time prolonged or the persulfate dosage increased, the formation of TCM and DCAN continuously decreased, while that of CH, 1,1,1-TCP and TCNM presented an increasing and then decreasing pattern. SO4•- activated benzoic acid (BA) to form phenolic compounds that enhanced the formation of TCM and CH, while it deactivated resorcinol to decrease the formation of TCM. SO4•- reacted with aliphatic amines such as methylamine (MA) and dimethylamine (DMA) to form nitro groups, which significantly increased the formation of TCNM in post chlorination, and the rate was determined to be higher than that of HO•. This study illuminated the diverse impacts of the structures of the precursors on DBP formation after UV/persulfate treatment, and DBP alteration depended on the reactivity between SO4•- and specific precursor.
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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
| | - 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, China
| | - Shaodong Hou
- Guangdong Shaoke Environmental Protection Technology Co., Ltd., Shaoguan, 512000, China
| | - Shiqian Zou
- Suzhou Environmental Monitoring Center, Suzhou, 215000, China
| | - Xibing Xu
- China Shipbuilding Industry Corporation International Engineering Co., Ltd., Beijing, 100121, China
| | - Huang Huang
- 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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Bio-Optimization of Chemical Parameters and Earthworm Biomass for Efficient Vermicomposting of Different Palm Oil Mill Waste Mixtures. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16122092. [PMID: 31200470 PMCID: PMC6616581 DOI: 10.3390/ijerph16122092] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 06/03/2019] [Accepted: 06/05/2019] [Indexed: 12/24/2022]
Abstract
The present study reports mathematical modelling of palm oil mill effluent and palm-pressed fiber mixtures (0% to 100%) during vermicomposting process. The effects of different mixtures with respect to pH, C:N ratio and earthworms have been optimized using the modelling parameters. The results of analysis of variance have established effect of different mixtures of palm oil mill effluent plus palm press fiber and time, under selected physicochemical responses (pH, C:N ratio and earthworm numbers). Among all mixtures, 60% mixture was achieved optimal growth at pH 7.1 using 16.29 C:N ratio in 15 days of vermicomposting. The relationship between responses, time and different palm oil mill waste mixtures have been summarized in terms of regression models. The obtained results of mathematical modeling suggest that these findings have potential to serve a platform for further studies in terms of kinetic behavior and degradation of the biowastes via vermicomposting.
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14
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Im D, Nakada N, Fukuma Y, Tanaka H. Effects of the inclusion of biological activated carbon on membrane fouling in combined process of ozonation, coagulation and ceramic membrane filtration for water reclamation. CHEMOSPHERE 2019; 220:20-27. [PMID: 30579170 DOI: 10.1016/j.chemosphere.2018.12.071] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Revised: 11/09/2018] [Accepted: 12/09/2018] [Indexed: 06/09/2023]
Abstract
We investigated the effects of the inclusion of biological activated carbon (BAC) on membrane fouling in combined process of ozonation, coagulation and ceramic membrane filtration (O3 + PACl + CMF) for treating secondary effluent. Inclusion of BAC between ozonation and coagulation reduced membrane permeability. The normalized flux decreased to 90% of the initial value after 305 h of operation in O3 + PACl + CMF, while it decreased to 20% in combined process of ozonation, BAC, coagulation and ceramic membrane filtration. BAC not only decreased residual ozone that is helpful to mitigate ceramic membrane fouling, but also released microorganisms. In addition, BAC doubled the integrated fluorescence intensity of soluble microbial products (SMP), which cause irreversible fouling. The SMP produced and accumulated by microorganisms on the BAC bed likely flowed into the BAC effluent with the microorganisms. The proportion of SMP in the extracted foulant increased from 25% without BAC to 31% with BAC. Moreover, the inclusion of BAC nearly doubled the concentration of protein in the extracted foulant to 13 g/m2 and quadrupled that of carbohydrate to 6 g/m2. BAC was effective in improving the quality of ceramic membrane permeates and reducing health risk associated with formaldehyde and N-nitrosodimethylamine. However, the release of SMP from BAC accelerated membrane fouling in subsequent ceramic membrane filtration.
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Affiliation(s)
- Dongbum Im
- Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University, 1-2 Yumihama, Otsu, Shiga, 520-0811, Japan
| | - Norihide Nakada
- Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University, 1-2 Yumihama, Otsu, Shiga, 520-0811, Japan.
| | - Yasuyuki Fukuma
- Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University, 1-2 Yumihama, Otsu, Shiga, 520-0811, Japan
| | - Hiroaki Tanaka
- Research Center for Environmental Quality Management, Graduate School of Engineering, Kyoto University, 1-2 Yumihama, Otsu, Shiga, 520-0811, Japan
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15
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Liu H, Rong J, Shen G, Song Y, Gu W, Liu X. A fluorescent probe for sequential sensing of MnO4− and Cr2O72− ions in aqueous medium based on a UCNS/TMB nanosystem. Dalton Trans 2019; 48:4168-4175. [DOI: 10.1039/c9dt00360f] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Distinguishable and sequential detection of MnO4− and Cr2O72− was realized by the reactions above and IFE between UCNS and oxTMB.
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Affiliation(s)
- Haiquan Liu
- College of Chemistry
- Nankai University
- Tianjin 300071
- China
- Collaborative Innovation Center of Chemical Science and Engineering
| | - Jianing Rong
- College of Chemistry
- Nankai University
- Tianjin 300071
- China
| | - Guoqiong Shen
- College of Chemistry
- Nankai University
- Tianjin 300071
- China
| | - Yao Song
- College of Chemistry
- Nankai University
- Tianjin 300071
- China
| | - Wen Gu
- College of Chemistry
- Nankai University
- Tianjin 300071
- China
- Collaborative Innovation Center of Chemical Science and Engineering
| | - Xin Liu
- College of Chemistry
- Nankai University
- Tianjin 300071
- China
- Collaborative Innovation Center of Chemical Science and Engineering
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16
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Liu X, Cai H, Zou J, Pang Z, Yuan B, Zhou Z, Cheng Q. Spectrophotometric determination of trace permanganate in water with N,N-diethyl-p-phenylenediamine (DPD). CHEMOSPHERE 2018; 212:604-610. [PMID: 30172042 DOI: 10.1016/j.chemosphere.2018.08.087] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Revised: 08/16/2018] [Accepted: 08/17/2018] [Indexed: 05/19/2023]
Abstract
A sensitive spectrophotometric method (the N,N-diethyl-p-phenylenediamine (DPD) method) was established for the determination of trace permanganate concentration (0-10 μM) in water. The DPD method was based on the oxidative coloration reaction where permanganate could oxidize DPD to form the red colored DPD radical (DPD•+) with a second-order rate constant of 2.96 × 104 M-1 s-1 at pH 6 (50 mM phosphate buffer). The generated DPD•+ could be quantitatively measured at 551 nm using an UV-Vis spectrophotometer. There was a good linear relationship (R2 = 0.999) between the absorbance of DPD•+ and permanganate concentration. The DPD method was highly sensitive, and the absorbance of generated DPD•+ at 551 nm was as high as 5.70 × 104 cm-1 per M (mol L-1) of permanganate. The reaction of permanganate with DPD in the pH range of 4.0-8.0 had a stoichiometric coefficient of 1:2.71. The residual absorbance of DPD•+ in ultrapure water and natural waters was fairly stable for 30 min. Limits of detection of the proposed DPD method in ultrapure water and natural waters were calculated to be as low as 0.010 μM and 0.017 μM, respectively. Moreover, trace permanganate concentrations of 0.04 and 0.10 μM were found in natural waters and wastewater by the proposed DPD method. Additionally, the DPD method could be applied to measure the second-order rate constants of the reaction of permanganate with phenol at pH 7.0 (28.2 M-1 s-1).
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Affiliation(s)
- Xin Liu
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, Fujian 361021, PR China
| | - Huahua Cai
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, Fujian 361021, PR China
| | - Jing Zou
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, Fujian 361021, PR China.
| | - Zijun Pang
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, Fujian 361021, PR China
| | - Baoling Yuan
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, Fujian 361021, PR China.
| | - Zhenming Zhou
- Institute of Municipal and Environmental Engineering, College of Civil Engineering, Huaqiao University, Xiamen, Fujian 361021, PR China
| | - Qingfeng Cheng
- College of Resources and Environment, Chengdu University of Information Technology, Chengdu, Sichuan 610225, PR China
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17
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Kosaka K, Iwatani A, Takeichi Y, Yoshikawa Y, Ohkubo K, Akiba M. Removal of haloacetamides and their precursors at water purification plants applying ozone/biological activated carbon treatment. CHEMOSPHERE 2018; 198:68-74. [PMID: 29421762 DOI: 10.1016/j.chemosphere.2018.01.093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 01/16/2018] [Accepted: 01/21/2018] [Indexed: 06/08/2023]
Abstract
Haloacetamides (HAcAms) are nitrogenous disinfection byproducts in drinking water. The profiles of six HAcAms and their formation potentials (FPs) upon chlorination at water purification plant 1 (WPP-1) in September 2016 and at WPP-2 in September 2016 and January 2017 were investigated. HAcAms were removed effectively when they were formed via intermediate chlorination during water purification processes. Removal of total HAcAm-FPs ranged from 50% to 75%. Coagulation/flocculation/sand filtration showed the highest removal of total HAcAm-FPs. As for individual HAcAms, while chlorinated acetamide-FPs were removed, brominated acetamide-FPs, particularly 2,2-dibromoacetamide, remained. The bromine incorporation factors increased during all water purification processes except ozonation and the ozone/hydrogen peroxide process for diHAcAms (2,2-dichloroacetamide, 2-bromo-2-chloroacetamide, and 2,2-dibromoacetamide). The trends in relationships between DOM indices (fractions of dissolved organic matter, ultraviolet absorbance at 260 nm, and fluorescence intensities representing humic-like and tryptophan-like compounds) and total HAcAm-FPs during ozonation and ozone/hydrogen peroxide process were different from those during other processes.
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Affiliation(s)
- Koji Kosaka
- Graduate School of Engineering, Kyoto University, C-1 Katsura, Nishikyo-ku, Kyoto, Kyoto, 615-8540, Japan.
| | - Azusa Iwatani
- Kanagawa Prefectural Enterprise Bureau, 1 Nihon-Odori, Naka-ku, Yokohama, Kanagawa, 231-8588, Japan
| | - Yuuki Takeichi
- Aichi Public Enterprise Bureau, 3-1-2 Sannomaru, Naka-ku, Nagoya, Aichi, 460-8501, Japan
| | - Yusuke Yoshikawa
- Waterworks Bureau, City of Kawasaki, 1 Miyamoto-cho, Kawasaki-ku, Kawasaki, Kanagawa, 210-8577, Japan
| | - Keiko Ohkubo
- National Institute of Public Health, 2-3-6 Minami, Wako, Saitama, 351-0197, Japan
| | - Michihiro Akiba
- National Institute of Public Health, 2-3-6 Minami, Wako, Saitama, 351-0197, Japan
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18
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Srithep S, Phattarapattamawong S. Kinetic removal of haloacetonitrile precursors by photo-based advanced oxidation processes (UV/H 2O 2, UV/O 3, and UV/H 2O 2/O 3). CHEMOSPHERE 2017; 176:25-31. [PMID: 28254711 DOI: 10.1016/j.chemosphere.2017.02.107] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 02/17/2017] [Accepted: 02/20/2017] [Indexed: 06/06/2023]
Abstract
The objective of the study is to evaluate the performance of conventional treatment process (i.e., coagulation, flocculation, sedimentation and sand filtration) on the removals of haloacetonitrile (HAN) precursors. In addition, the removals of HAN precursors by photo-based advanced oxidation processes (Photo-AOPs) (i.e., UV/H2O2, UV/O3, and UV/H2O2/O3) are investigated. The conventional treatment process was ineffective to remove HAN precursors. Among Photo-AOPs, the UV/H2O2/O3 was the most effective process for removing HAN precursors, followed by UV/H2O2, and UV/O3, respectively. For 20min contact time, the UV/H2O2/O3, UV/H2O2, and UV/O3 suppressed the HAN formations by 54, 42, and 27% reduction. Increasing ozone doses from 1 to 5 mgL-1 in UV/O3 systems slightly improved the removals of HAN precursors. Changes in pH (6-8) were unaffected most of processes (i.e., UV, UV/H2O2, and UV/H2O2/O3), except for the UV/O3 system that its efficiency was low in the weak acid condition. The pseudo first-order kinetic constant for removals of dichloroacetonitrile precursors (k'DCANFP) by the UV/H2O2/O3, UV/H2O2 and standalone UV systems were 1.4-2.8 orders magnitude higher than the UV/O3 process. The kinetic degradation of dissolved organic nitrogen (DON) tended to be higher than the k'DCANFP value. This study firstly differentiates the kinetic degradation between DON and HAN precursors.
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Affiliation(s)
- Sirinthip Srithep
- Department of Environmental Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, Thailand
| | - Songkeart Phattarapattamawong
- Department of Environmental Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi, Bangkok, Thailand; Research Program in Hazardous Substance Management in Agricultural Industry, Center of Excellence on Hazardous Substance Management (HSM), Thailand.
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19
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Adeleke AO, Latiff AAA, Al-Gheethi AA, Daud Z. Optimization of operating parameters of novel composite adsorbent for organic pollutants removal from POME using response surface methodology. CHEMOSPHERE 2017; 174:232-242. [PMID: 28171839 DOI: 10.1016/j.chemosphere.2017.01.110] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2016] [Revised: 01/20/2017] [Accepted: 01/21/2017] [Indexed: 06/06/2023]
Abstract
The present work aimed to develop a novel composite material made up of activated cow bone powder (CBP) as a starting material for reducing chemical oxygen demand (COD) and ammonia-nitrogen (NH3N) from palm oil mill effluent (POME). The optimization of the reduction efficiency was investigated using response surface methodology (RSM). Six independent variables used in the optimization experiments include pH (4-10), speed (0.27-9.66 rcf), contact time (2-24 h), particle size (1-4.35 mm), dilution factor (100-500) and adsorbent dosage (65-125 g/L). The chemical functional groups were determined using Fourier transform irradiation (FTIR). The elemental composition were detected using SEM-EDX, while thermal decomposition was investigated using thermo gravimetric analysis (TGA) in order to determine the effects of carbonization temperature on the adsorbent. The results revealed that the optimal reduction of COD and NH3N from raw POME was observed at pH 10, 50 rpm, within 2 h and 3 mm of particle size as well as at dilution factor of 500 and 125 g L-1 of adsorbent dosage, the observed and predicted reduction were 89.60 vs. 85.01 and 75.61 vs. 74.04%, respectively for COD and NH3N. The main functional groups in the adsorbent were OH, NH, CO, CC, COC, COH, and CH. The SEM-EDX analysis revealed that the CBP-composite has a smooth surface with high contents of carbon. The activated CBP has very stable temperature profile with no significant weight loss (9.85%). In conclusion, the CBP-composite investigated here has characteristics high potential for the remediation of COD and NH3N from raw POME.
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Affiliation(s)
- A O Adeleke
- Department of Water and Environmental Engineering, Faculty of Civil & Environmental Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), 86400, Parit Raja, Batu Pahat, Johor, Malaysia.
| | - Ab Aziz Ab Latiff
- Department of Water and Environmental Engineering, Faculty of Civil & Environmental Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), 86400, Parit Raja, Batu Pahat, Johor, Malaysia
| | - A A Al-Gheethi
- Department of Water and Environmental Engineering, Faculty of Civil & Environmental Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), 86400, Parit Raja, Batu Pahat, Johor, Malaysia
| | - Zawawi Daud
- Department of Water and Environmental Engineering, Faculty of Civil & Environmental Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), 86400, Parit Raja, Batu Pahat, Johor, Malaysia
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20
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Chu W, Yao D, Deng Y, Sui M, Gao N. Production of trihalomethanes, haloacetaldehydes and haloacetonitriles during chlorination of microcystin-LR and impacts of pre-oxidation on their formation. JOURNAL OF HAZARDOUS MATERIALS 2017; 327:153-160. [PMID: 28064143 DOI: 10.1016/j.jhazmat.2016.12.058] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 12/07/2016] [Accepted: 12/29/2016] [Indexed: 06/06/2023]
Abstract
Microcystins (MCs) in drinking water have gained much attention due to their adverse health effects. However, little is known about the impact of pre-oxidation in the formation of disinfection by-products (DBPs) during the downstream chlorination of MCs. The present study examined the formation of both carbonaceous and nitrogenous DBPs from chlorination of MC-LR (the most abundant MC species) and evaluated the impact of permanganate (PM), hydrogen peroxide (H2O2) and chlorine dioxide (ClO2) pre-oxidation on the DBP formation in chlorination. Higher yields of chloroform (CF) (maximum 43.0%) were observed from chlorination of MC-LR than free amino acids which are included in MC-LR structure. Chloral hydrate (CH) and dichloroacetonitrile (DCAN) were also produced from the chlorination of MC-LR, and the latter one was formed probably due to the chlorination of peptide bonds. A high pH favored the production of CF and CH, but inhibited the formation of DCAN. In the presence of bromide, bromo-DBPs could be produced to pose a threat. For example, 0.58μg/L of tribromoacetaldehyde was produced from the chlorination of MC-LR at Br-=200μg/L. PM and ClO2 pre-oxidation could both reduce the DBP formation from MC-LR. In contrast, H2O2 appeared not to significantly control the DBP formation.
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Affiliation(s)
- Wenhai Chu
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
| | - Dechang Yao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yang Deng
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, USA
| | - Minghao Sui
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Naiyun Gao
- State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
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21
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Chang Y, Bai Y, Qu J. Does KMnO4 preoxidation reduce the genotoxicity of disinfection by-products? CHEMOSPHERE 2016; 163:73-80. [PMID: 27521641 DOI: 10.1016/j.chemosphere.2016.08.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/01/2016] [Accepted: 08/02/2016] [Indexed: 06/06/2023]
Abstract
Potassium permanganate (KMnO4) preoxidation is capable of affecting the formation of disinfection by-products (DBPs). However, few studies have focused on the toxicity of DBPs after KMnO4 preoxidation, which is an important index to evaluate alternative treatment processes. Herein genotoxicity (SOS/umu test) was used to clarify the impact of KMnO4 preoxidation on the chlorination byproducts produced from two representative precursors, tyrosine (Tyr) and 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid (BP-4), and their mixture. Results revealed that although KMnO4 could not oxidize BP-4, after chlorination KMnO4 could oxidize the chlorination byproducts of BP-4 and thus decrease the genotoxicity production. For Tyr, KMnO4 preoxidation could increase or decrease the genotoxicity of DBPs, depending on the KMnO4 dose. The optimal initial molar ratio of KMnO4 to Tyr was confirmed to be 1:1. It has been proved that both the oxidation of Tyr by KMnO4 and manganese dioxide (MnO2, the reduction product of KMnO4) and the oxidation of chlorination byproducts by MnO2 can decrease the genotoxicity production of chlorinated Tyr. Remarkably, during chlorination, the competition of manganese(II) oxidation with organic oxidation can result in less chlorine reacting with organics, to induce an increase in genotoxicity. This is the main cause for the increase in genotoxicity of chlorinated Tyr after KMnO4 preoxidation. Additionally, the genotoxicity of the chlorinated mixture was shifted from being higher than the sum of individual genotoxicities of the chlorinated precursors to being lower than their sum with increasing KMnO4 dosage, due to the combined effects between the preoxidation-chlorination products from the two compounds.
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Affiliation(s)
- Yangyang Chang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yaohui Bai
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.
| | - Jiuhui Qu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
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