251
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Sun J, Liu L, Yang F. Electro-enhanced chlorine-mediated ammonium nitrogen removal triggered by an optimized catalytic anode for sustainable saline wastewater treatment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 776:146035. [PMID: 33652320 DOI: 10.1016/j.scitotenv.2021.146035] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/18/2021] [Accepted: 02/18/2021] [Indexed: 06/12/2023]
Abstract
Electrochemical technology has unique superiorities in chlorine-mediated pollutant oxidation, but has limited application in saline wastewater treatment due to inadequate efficiency and high energy consumption. To promote electrochemical oxidation capacity, a novel but low-cost electrode containing TiO2/Co-WO3/SiC was prepared and optimized, achieving highly efficient chlorine-mediated ammonium nitrogen oxidation (98.3 ± 2.2% in 120 min, with initial NH4+-N of 10.2 ± 0.5 mg L-1) in a simple electrochemical system with supplied current density only at 1.00 mA cm-2. Comparing with unmodified carbon fiber cloth, the catalytic anode achieved 96.0% nitrogen selectivity, enhanced the system current efficiency by 20.6% and reduced the energy consumption by 54.4%, making the treatment of simulated mariculture wastewater both energy-saving (36.5 ± 2.8 kWh kg-1 NH4+-N) and cost-effective (1.45 US$ m-3), comparing with previously reported electrochemical processes (54-622 kWh kg-1 NH4+-N). The nitrogen content (<1 mg L-1) in the treated wastewater, containing only 0.18 mg L-1 NH4+-N, meets the discharge standard of mariculture wastewater. The promoted electrochemical oxidation should be attributed to the chloride derived species (HOCl and ClO-) and related active species (Cl, ClO, OH, etc.). This easily prepared and reusable catalytic electrode is a promising alternative to conventional anode materials in sustainable electrochemical treatment of saline wastewater.
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Affiliation(s)
- Jiaqi Sun
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science & Technology, Dalian University of Technology, Dalian 116024, China
| | - Lifen Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science & Technology, Dalian University of Technology, Dalian 116024, China; School of Ocean Science and Technology, Dalian University of Technology, Panjin, China.
| | - Fenglin Yang
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science & Technology, Dalian University of Technology, Dalian 116024, China
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252
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Clark JA, Yang Y, Ramos NC, Hillhouse HW. Selective oxidation of pharmaceuticals and suppression of perchlorate formation during electrolysis of fresh human urine. WATER RESEARCH 2021; 198:117106. [PMID: 33933918 DOI: 10.1016/j.watres.2021.117106] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 03/12/2021] [Accepted: 03/31/2021] [Indexed: 06/12/2023]
Abstract
Urine comprises only a small (~1%) volumetric fraction of municipal wastewater, but represents a dominant source of pharmaceuticals, many of which may pass through conventional wastewater treatment and pose risks to aquatic ecosystems. Point-source treatment of source-separated urine presents a unique opportunity to degrade pharmaceuticals before dilution with wastewater, and electrochemical advanced oxidation processes are one increasingly investigated option. However, they often lead to the formation of oxidation byproducts including chlorate, perchlorate at very high concentrations. Here, we show that the high urea content of fresh human urine suppresses the formation of oxychlorides by inhibiting formation of HOCl/OCl‒ during electrolysis, while still enabling pharmaceutical degradation due to the slow rate of urea oxidation by •OH. This results in improved performance compared to equivalent treatment of hydrolyzed aged urine. This electrochemical oxidation scheme is shown to degrade the model contaminants cyclophosphamide and sulfamethoxazole with surface-area-to-volume-normalized pseudo-first-order rate constants greater than 0.08 cm/min in authentic fresh human urine. It results in ~100 × decrease in pharmaceutical concentrations in 2 h while generating ~1000 × lower oxychloride byproduct concentrations in synthetic fresh urine than synthetic hydrolyzed aged urine matrixes. Importantly, this proof-of-principle shows that simple and safe electrochemical methods can be used for point-source-remediation of pharmaceuticals in fresh human urine (before storage and hydrolysis), without formation of significant oxychloride byproducts.
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Affiliation(s)
- James A Clark
- Department of Chemical Engineering, Clean Energy Institute, Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA, 98195-1750, USA
| | - Yuhang Yang
- Department of Materials Science and Engineering, University of Washington, Seattle, WA, 98195-2120, USA
| | - Nathanael C Ramos
- Department of Chemical Engineering, Clean Energy Institute, Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA, 98195-1750, USA
| | - Hugh W Hillhouse
- Department of Chemical Engineering, Clean Energy Institute, Molecular Engineering & Sciences Institute, University of Washington, Seattle, WA, 98195-1750, USA.
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253
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Degradation of Trimethoprim Using the UV/Free Chlorine Process: Influencing Factors and Optimal Operating Conditions. WATER 2021. [DOI: 10.3390/w13121656] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Trimethoprim (TMP) is a pharmaceutical compound, which is commonly found in the water environment. The UV/chlorine process forms several reactive species, including hydroxyl radicals (HO•) and reactive chlorine species, to degrade contaminants. The influencing factors and the optimal operational conditions for the degradation of TMP by the UV/chlorine process were investigated. The degradation of TMP was much faster by the UV/chlorine process as compared to the UV alone or free chlorine alone process. A kinetic model was developed to simulate the degradation of TMP and determine the unknown rate constants. This study also predicted the relative contributions of each of the reactive species and photolysis using the developed kinetic model. It was found that the ClO• radical was the major reactant responsible for the degradation of TMP. Furthermore, the most important finding was the identification of the best operational conditions. The best operational conditions resulted in the lowest use of energy and electrical energy per order (EE/O), namely, (1) for the ultrapure water, the optimum intensity of the UV light and the free chlorine dosage were 2.56 Einstein/L·s and 0.064 mM, respectively, with a minimum EE/O of 0.136 kWh/m3; and (2) for the water matrix containing 3 mg/L NOM, the optimum intensity of the UV light and the free chlorine dosage were 3.45 Einstein/L s and 0.172 mM, respectively, with a minimum EE/O of 0.311 kWh/m3.
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254
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Yang Q, Guo Y, Xu J, Wu X, He B, Blatchley ER, Li J. Photolysis of N-chlorourea and its effect on urea removal in a combined pre-chlorination and UV 254 process. JOURNAL OF HAZARDOUS MATERIALS 2021; 411:125111. [PMID: 33485223 DOI: 10.1016/j.jhazmat.2021.125111] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 12/27/2020] [Accepted: 01/10/2021] [Indexed: 06/12/2023]
Abstract
Urea is one of the most important nitrogenous organic pollutants in water, and its removal attracts attention because of a growing concern related to water eutrophication. Urea has previously been considered to be largely unaffected by the UV-chlorine process. However, N-chlorourea, an intermediate of urea chlorination, has been shown to absorb ultraviolet radiation, and as such its photolysis is possible. Experiments were conducted to quantify the kinetics of N-chlorourea degradation under UV254 irradiation. The results showed that about 92% of N-chlorourea was degraded under UV254 irradiation. Ammonia and nitrate were detected as the primary nitrogen containing products of the photolysis of N-chlorourea. Solution pH ranging from 3.0 to 7.5 influenced the distribution of these products but not on the degradation rate. Based on these data, a possible pathway of photodegradation of N-chlorourea under UV254 is proposed. The degradation of urea was also achieved by the photolysis of N-chlorourea during the combined pre-chlorination and UV254 process. Insights gained in this study may be useful for exploring the potential of combined pre-chlorination and UV254 process on urea removal in water treatment.
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Affiliation(s)
- Qian Yang
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, PR China
| | - Yang Guo
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, PR China
| | - Jie Xu
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, PR China
| | - Xingyi Wu
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, PR China
| | - Bingying He
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, PR China
| | - Ernest R Blatchley
- Lyles School of Civil Engineering, 550 Stadium Mall Drive, Purdue University, West Lafayette, IN 47907, USA; Division of Environmental & Ecological Engineering, Purdue University, West Lafayette, IN 47907, USA
| | - Jing Li
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, PR China.
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255
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Wang A, Hua Z, Wu Z, Chen C, Hou S, Huang B, Wang Y, Wang D, Li X, Li C, Fang J. Insights into the effects of bromide at fresh water levels on the radical chemistry in the UV/peroxydisulfate process. WATER RESEARCH 2021; 197:117042. [PMID: 33784605 DOI: 10.1016/j.watres.2021.117042] [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: 12/18/2020] [Revised: 02/18/2021] [Accepted: 03/10/2021] [Indexed: 06/12/2023]
Abstract
Bromide (Br-) is a typical scavenger to sulfate radical (SO4•-) and hydroxyl radical (HO•), which simultaneously forms secondary reactive bromine species (RBS) such as Br• and Br2•-. This study investigated the effects of Br- at fresh water levels (~μM) on the radical chemistry in the UV/peroxydisulfate (UV/PDS) process by combining the degradation kinetics of probe compounds (nitrobenzene, metronidazole, and benzoate) with kinetic model. Br- at 1 - 50 μM promoted the conversion from SO4•- to HO• and RBS in the UV/PDS process. At pH 7, the concentration of SO4•- monotonically decreased by 31.5 - 94.8% at 1 - 50 μM Br-, while that of HO• showed an increasing and then decreasing pattern, with a maximum increase by 171.7% at 5 μM Br-. The concentrations of Br• and Br2•- (10-12 - 10-10 M) were 2 - 3 orders of magnitude higher than SO4•- and HO•. Alkaline condition promoted the conversion from SO4•- to HO•, and drove the transformation from RBS to HO•, resulting in much lower concentrations of RBS at pH 10. Br- at 1 μM and 5 μM decreased the pseudo-first-order reaction rates (k's) of 15 pharmaceuticals and personal care products (PPCPs) by 15.2 - 73.9%, but increased k's of naproxen and ibuprofen by 13.7 - 57.3% at pH 7. The co-existence of 10 - 1000 μM Cl- with 5 μM Br- further promoted the conversion from SO4•- to HO• compared to Br- alone. Bicarbonate consumed SO4•- and HO• but slightly affected RBS, while natural organic matter (NOM) exerted scavenging effects on HO• and RBS more significantly than SO4•-. This study demonstrated that Br- at fresh water levels significantly altered the radical chemistry of the UV/PDS process, especially for promoting the formation of HO•.
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Affiliation(s)
- Anna Wang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, 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, China
| | - Zihao Wu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, 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, China
| | - Shaodong Hou
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Bangjie 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
| | - Yuge Wang
- School of Civil Engineering, Southeast University, Nanjing 210096, PR China
| | - Ding Wang
- General Institute of Water Resources and Hydropower Planning and Design, Beijing 100120, China
| | - Xuchun Li
- School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018, China
| | - Chuanhao 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
| | - 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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256
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Zhang T, Lv K, Lu Q, Wang L, Liu X. Removal of antibiotic-resistant genes during drinking water treatment: A review. J Environ Sci (China) 2021; 104:415-429. [PMID: 33985744 DOI: 10.1016/j.jes.2020.12.023] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/14/2020] [Accepted: 12/21/2020] [Indexed: 06/12/2023]
Abstract
Once contaminate the drinking water source, antibiotic resistance genes (ARGs) will propagate in drinking water systems and pose a serious risk to human health. Therefore, the drinking water treatment processes (DWTPs) are critical to manage the risks posed by ARGs. This study summarizes the prevalence of ARGs in raw water sources and treated drinking water worldwide. In addition, the removal efficiency of ARGs and related mechanisms by different DWTPs are reviewed. Abiotic and biotic factors that affect ARGs elimination are also discussed. The data on presence of ARGs in drinking water help come to the conclusion that ARGs pollution is prevalent and deserves a high priority. Generally, DWTPs indeed achieve ARGs removal, but some biological treatment processes such as biological activated carbon filtration may promote antibiotic resistance due to the enrichment of ARGs in the biofilm. The finding that disinfection and membrane filtration are superior to other DWTPs adds weight to the advice that DWTPs should adopt multiple disinfection barriers, as well as keep sufficient chlorine residuals to inhibit re-growth of ARGs during subsequent distribution. Mechanistically, DWTPs obtain direct and inderect ARGs reduction through DNA damage and interception of host bacterias of ARGs. Thus, escaping of intracellular ARGs to extracellular environment, induced by DWTPs, should be advoided. This review provides the theoretical support for developping efficient reduction technologies of ARGs. Future study should focus on ARGs controlling in terms of transmissibility or persistence through DWTPs due to their biological related nature and ubiquitous presence of biofilm in the treatment unit.
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Affiliation(s)
- Tuqiao Zhang
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou 310058, China
| | - Kunyuan Lv
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou 310058, China
| | - Qingxiao Lu
- Ocean College, Zhejiang University, Hangzhou 310058, China
| | - Lili Wang
- Environmental Engineering, Jiyang College of Zhejiang A & F University, Zhuji 311800, China
| | - Xiaowei Liu
- Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University, Hangzhou 310058, China; Ocean College, Zhejiang University, Hangzhou 310058, China.
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257
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Lai X, Ning XA, Zhang Y, Li Y, Li R, Chen J, Wu S. Treatment of simulated textile sludge using the Fenton/Cl - system: The roles of chlorine radicals and superoxide anions on PAHs removal. ENVIRONMENTAL RESEARCH 2021; 197:110997. [PMID: 33713713 DOI: 10.1016/j.envres.2021.110997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/20/2021] [Accepted: 03/05/2021] [Indexed: 06/12/2023]
Abstract
The main content of this work is to investigate the removal of polycyclic aromatic hydrocarbons (PAHs: phenanthrene, anthracene, and fluoranthene) from simulated sludge solid phase employing an Fenton/Cl- system under various Cl- contents and pH values. The steady-state concentrations of the hydroxyl, chlorine, and dichloride anion radicals ([·OH]ss, [·Cl]ss, and [Cl2·-]ss) in heterogeneous system were first measured using tert-butanol, nitrobenzene, and benzoic acid. The outcomes exhibited that increasing the Cl- content from 50 to 2000 mg/L (pH = 3.0) or raising the pH from 3.0 to 5.0 (1000 mg/L Cl-) caused [·OH]ss to continuously decrease and [Cl2·-]ss and the concentration of superoxide anions (HO2·/O2·-) to continuously increase. When the pH was 3.0 and the Cl- concentration was 1000 mg/L, [·Cl]ss had a maximum value of 9.27 × 10-14 M. Combining the results of PAH removal, radical quenching, and product analysis, it was found that ·Cl in the Fenton/Cl- system promoted the oxidative degradation of phenanthrene without forming chlorination byproducts. Furthermore, HO2·/O2·- was helpful in removing anthracene and fluoranthene. Under the environment of high Cl- content (≥1000 mg/L), PAHs could be removed more effectively by using HO2·/O2·-. This investigation underpins further study on the regulation of reactive species and the efficient degradation of target organic matter in Fenton/Cl- system, and provides a basis for studying the formation of chlorinated or toxic byproducts in the process of treating textile dyeing sludge by Fenton.
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Affiliation(s)
- Xiaojun Lai
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Xun-An Ning
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Yaping Zhang
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Yang Li
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Riwen Li
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Jiayi Chen
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Shiyin Wu
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, China
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258
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Sengar A, Vijayanandan A. Comprehensive review on iodinated X-ray contrast media: Complete fate, occurrence, and formation of disinfection byproducts. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 769:144846. [PMID: 33736235 DOI: 10.1016/j.scitotenv.2020.144846] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 12/19/2020] [Accepted: 12/20/2020] [Indexed: 05/22/2023]
Abstract
Iodinated contrast media (ICM) are drugs which are used in medical examinations for organ imaging purposes. Wastewater treatment plants (WWTPs) have shown incapability to remove ICM, and as a consequence, ICM and their transformation products (TPs) have been detected in environmental waters. ICM show limited biotransformation and low sorption potential. ICM can act as iodine source and can react with commonly used disinfectants such as chlorine in presence of organic matter to yield iodinated disinfection byproducts (IDBPs) which are more cytotoxic and genotoxic than conventionally known disinfection byproducts (DBPs). Even highly efficient advanced treatment systems have failed to completely mineralize ICM, and TPs that are more toxic than parent ICM are produced. This raises issues regarding the efficacy of existing treatment technologies and serious concern over disinfection of ICM containing waters. Realizing this, the current review aims to capture the attention of scientific community on areas of less focus. The review features in depth knowledge regarding complete environmental fate of ICM along with their existing treatment options.
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Affiliation(s)
- Ashish Sengar
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Arya Vijayanandan
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110016, India.
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259
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Li ZY, Wang L, Liu YL, He PN, Zhang X, Chen J, Gu HT, Zhang HC, Ma J. Overlooked enhancement of chloride ion on the transformation of reactive species in peroxymonosulfate/Fe(II)/NH 2OH system. WATER RESEARCH 2021; 195:116973. [PMID: 33677242 DOI: 10.1016/j.watres.2021.116973] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 02/17/2021] [Accepted: 02/22/2021] [Indexed: 06/12/2023]
Abstract
Though hydroxylamine (NH2OH) is effective for accelerating pollutants degradation in Fenton and Fenton-like systems, the effect of anions simultaneously introduced by the hydroxylamine salts have always been ignored. Herein, effect of two commonly used hydroxylamine salts, hydroxylamine hydrochloride (NH2OH·HCl) and hydroxylamine sulfate [(NH2OH)2·H2SO4], for the degradation of dimethyl phthalate (DMP) in peroxymonosulfate (PMS)/Fe(II) system was comparatively investigated. Degradation efficiency of DMP with NH2OH·HCl was 1.6 times of that with same dosages of (NH2OH)2·H2SO4. SO4·-, Fe(IV) and ·OH formed in the PMS/Fe(II)/NH2OH system, but ·OH was the major species for DMP degradation. Addition of Cl- significantly improved the production of ·OH and Cl·, and the exposure dose of ·OH (CT·OH) was more than 10 times that of CTCl· as the concentration of Cl- increased to 1 mM. Calculations based on branching ratios of Cl· and ·OH indicated that the reactions of Cl- with SO4·- and Cl· with H2O were not the only production sources of ·OH in the system. Further experiments with methyl phenyl sulfoxide (PMSO) as the probe indicated that Cl- would facilitate the shift of reactive species from Fe(IV) to radicals (SO4·- or ·OH) in the system. Both hydroxylation and nitration intermediate products were detected in the oxidation of DMP. Cl- promoted the formation of hydroxylation intermediates and reduced the formation of nitration intermediates. This study revealed for the first time that Cl- could shift reactive species from Fe(IV) to radicals in PMS/Fe(II) system, raising attention to the influence of the coexisting anions (especially Cl-) for pollutants oxidation in iron-related oxidation processes.
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Affiliation(s)
- Zhuo-Yu Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Lu Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Yu-Lei Liu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Pei-Nan He
- State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Xin Zhang
- State Key Laboratory of Chemical Resource Engineering, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, PR China
| | - Jia Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Hai-Teng Gu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Hao-Chen Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, PR China
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260
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Wang P, Bu L, Wu Y, Deng J, Zhou S. Mechanistic insights into paracetamol transformation in UV/NH 2Cl process: Experimental and theoretical study. WATER RESEARCH 2021; 194:116938. [PMID: 33636666 DOI: 10.1016/j.watres.2021.116938] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/20/2021] [Accepted: 02/14/2021] [Indexed: 05/28/2023]
Abstract
The UV/monochloramine (NH2Cl) process is an advanced oxidation process that can effectively remove emerging contaminants (ECs). However, the degradation mechanisms of reactive radicals with ECs are not clear. In this work, we combined theoretical calculations with experimental studies to investigate the kinetics and mechanism of radical-mediated degradation of paracetamol (AAP) in UV/NH2Cl process. The degradation of AAP in UV/NH2Cl process accords with the pseudo first-order kinetics. Impact factors including NH2Cl dose, pH, natural organic matter, HCO3-, and NO3- were evaluated. The reaction mechanisms of AAP with hydroxyl radical (HO·), reactive chlorine species (RCS), and reactive nitrogen species (RNS) were discussed in detail. Specifically, HO· attacked AAP mainly through hydrogen atom transfer (HAT) and radical adduct formation (RAF), while Cl2·- play a certain role through single electron transfer (SET). ·NH2 and Cl· destructed AAP mainly through HAT. Based on the mechanism analysis, the second-order rate constants of AAP reacts with HO·, Cl·, ·NH2, ClO·, Cl2·- and ·NO2 were calculated through transition state theory as 2.66×109 M-1 s-1, 2.61×109 M-1 s-1, 1.02×107 M-1 s-1, 7.74×106 M-1 s-1, 1.32×106 M-1 s-1, 1.48×103 M-1 s-1 respectively. The second-order rate constants were then used to distinguish the contribution of radicals to the degradation of AAP. Thirteen transformation products were identified by high-resolution mass spectrometry. Combined active sites with potential energy surface, the detailed reaction pathways were proposed. Overall, this study provides deep insights into the mechanism of radical-mediated degradation of AAP.
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Affiliation(s)
- Pin Wang
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Lingjun Bu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China.
| | - Yangtao Wu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Jing Deng
- College of Civil Engineering, Zhejiang University of Technology, Hangzhou, 310023, China
| | - Shiqing Zhou
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China.
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261
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Lei X, Lei Y, Zhang X, Yang X. Treating disinfection byproducts with UV or solar irradiation and in UV advanced oxidation processes: A review. JOURNAL OF HAZARDOUS MATERIALS 2021; 408:124435. [PMID: 33189471 DOI: 10.1016/j.jhazmat.2020.124435] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 06/11/2023]
Abstract
This review focuses on the degradation kinetics and mechanisms of disinfection byproducts (DBPs) under UV and solar irradiation and in UV-based advanced oxidation processes (AOPs). A total of 59 such compounds are discussed. The processes evaluated are low pressure, medium pressure and vacuum UV irradiation, solar irradiation together with UV/hydrogen peroxide, UV/persulfate and UV/chlorine AOPs. Under UV and solar irradiation, the photodegradation rates of N-nitrosamines are much higher than those of halogenated DBPs. Among halogenated DBPs, those containing iodine are photodegraded more rapidly than those containing bromine or chlorine. This is due to differences in their bond energies (EN-N < EC-I < EC-Br < EC-Cl). Molar absorption coefficients at 254 nm and energy gaps can be used to predict the photodegradation rates of DBPs under low pressure UV irradiation. But many DBPs of interest cannot be degraded to half their original concentration with less than a 500 mJ cm-2 dose of low pressure UV light. HO• generally contributes to less than 30% of the degradation of DBPs except iodo-DBPs in UV/H2O2 AOPs. Reaction mechanisms under UV irradiation and in HO•-mediated oxidation are also summarized. N-N bond cleavage initiates their direct UV photolysis of N-nitrosamines as C-X cleavage does among halogenated compounds. HO• generally initiates degradation via single electron transfer, addition and hydrogen abstraction pathways. Information on the reaction rate constants of SO4•- and halogen radicals with DBPs is rather limited, and little information is available about their reaction pathways. Overall, this review provides improved understanding of UV, solar and AOPs.
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Affiliation(s)
- Xin Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Yu Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Xinran Zhang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Xin Yang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China.
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262
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Sgroi M, Anumol T, Vagliasindi FGA, Snyder SA, Roccaro P. Comparison of the new Cl 2/O 3/UV process with different ozone- and UV-based AOPs for wastewater treatment at pilot scale: Removal of pharmaceuticals and changes in fluorescing organic matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 765:142720. [PMID: 33572038 DOI: 10.1016/j.scitotenv.2020.142720] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 09/27/2020] [Accepted: 09/27/2020] [Indexed: 06/12/2023]
Abstract
This work critically compared the removal of fluorescing PARAFAC components and selected pharmaceuticals (carbamazepine, fluoxetine, gemfibrozil, primidone, sulfamethoxazole, trimethoprim) from a tertiary wastewater effluent by different UV- and ozone-based advanced oxidation processes (AOPs) operated at pilot-scale. Investigated AOPs included UV/H2O2, UV/Cl2, O3, O3/UV, H2O2/O3/UV, and the new Cl2/O3/UV. AOPs comparison was accomplished using various ozone doses (0-9 mg/L), UV fluences (191-981 mJ/cm2) and radical promoter concentrations of Cl2 = 0.04 mM and H2O2 = 0.29 mM. Chlorine-based AOPs produced radical species that reacted more selectively with pharmaceuticals than radical species and oxidants generated by other AOPs. Tryptophan-like substances and humic-like fluorescing compounds were the most degraded components by all AOPs, which were better removed than microbial products and fulvic-like fluorescing substances. Removal of UV absorbance at 254 (UV254) nm was always low. Overall, chlorine-based AOPs were more effective to reduce fluorescence intensities than similar H2O2-based AOPs. The Cl2/O3/UV process was the most effective AOP to degrade all target micro-pollutants except primidone. On the other hand, the oxidation performance of pharmaceuticals by other ozone-based AOPs followed the order H2O2/O3/UV > O3/UV > O3. UV/Cl2 process outcompeted UV/H2O2 only for the removal of trimethoprim and sulfamethoxazole. Correlations between the removal of pharmaceuticals and spectroscopic indexes (PARAFAC components and UV254) had unique regression parameters for each compound, surrogate parameter and oxidation process. Particularly, a diverse PARAFAC component for each investigated AOP resulted to be the most sensitive surrogate parameter able to monitor small changes of pharmaceuticals removal.
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Affiliation(s)
- Massimiliano Sgroi
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Tarun Anumol
- Agilent Technologies Inc., 2850 Centerville Road, Wilmington, DE 19808, USA; Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, AZ, 85721, USA
| | - Federico G A Vagliasindi
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Shane A Snyder
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, AZ, 85721, USA; Nanyang Technological University, Nanyang Environment & Water Research Institute, 1 Cleantech Loop, CleanTech One, #06-08, 637141, Singapore.
| | - Paolo Roccaro
- Department of Civil Engineering and Architecture, University of Catania, Viale A. Doria 6, 95125 Catania, Italy.
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263
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Chen C, Du Y, Zhou Y, Wu Q, Zheng S, Fang J. Formation of nitro(so) and chlorinated products and toxicity alteration during the UV/monochloramine treatment of phenol. WATER RESEARCH 2021; 194:116914. [PMID: 33636667 DOI: 10.1016/j.watres.2021.116914] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 02/03/2021] [Accepted: 02/04/2021] [Indexed: 06/12/2023]
Abstract
The UV/monochloramine (UV/NH2Cl) process is an emerging advanced oxidation process (AOP) to remove organic contaminants in water treatment with radicals including hydroxyl radicals (HO•), reactive chlorine species (RCS) and reactive nitrogen species (RNS). This study investigated the formation of nitro(so) and chlorinated products and toxicity alteration during the UV/NH2Cl treatment of phenol. RNS and/or RCS induced the formation of nitro(so), chlorinated and polymeric compounds during phenol transformation by UV/NH2Cl. These compounds dramatically increased the cytotoxicity to Chinese hamster ovary cells after 20 min UV/NH2Cl treatment, which was 10 times higher than that after 24 h chloramination. The increase of cytotoxicity in UV/NH2Cl was primarily attributable to 4-nitrosophenol, and the cytotoxicity followed the order of 4-nitrosophenol >> 4-nitrophenol > 2,4,6-trichlorophenol > 2,4-dichlorophenol > phenol. 4-Nitrosophenol was significantly generated by the combination of •NO and phenoxy radical, where the maximum conversion rates of phenol to 4-nitrosophenol increased from 4.9% to 62.4% when pH increased from 5 to 10. The highest conversion rate was at pH 10 because the •NO concentration increased with increasing pH from 5 to 10 in UV/NH2Cl, as verified by the electron paramagnetic resonance (EPR) analysis. Nitrophenols were also detected at much lower concentrations than 4-nitrosophenol, which were mainly formed by the oxidation of 4-nitrosophenol and the combination of •NO2 with phenoxy radicals. RCS was responsible for the formation of chlorinated products mainly through Cl• addition and the reactions of Cl•/Cl2•- with phenoxy radicals. Also, RCS and RNS significantly enhanced the formation of carbonaceous (i.e., chloroform and chloral hydrate) and nitrogenous disinfection byproducts (i.e., chloropicrin and dichloroacetonitrile) in UV/NH2Cl. This study indicates that the UV/NH2Cl treatment significantly increased toxicity and validates the roles of RNS and RCS in producing toxic nitro(so) and chlorinated products.
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Affiliation(s)
- 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
| | - Ye Du
- Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen, 518055, PR China
| | - Yujie Zhou
- Hainan Provincial Department of Ecological Environment, Haikou, 570203, PR China
| | - Qianyuan Wu
- Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen, 518055, PR China
| | - Shanshan Zheng
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, 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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264
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Liu Z, Xu B, Zhang TY, Hu CY, Tang YL, Dong ZY, Cao TC, El-Din MG. Formation of disinfection by-products in a UV-activated mixed chlorine/chloramine system. JOURNAL OF HAZARDOUS MATERIALS 2021; 407:124373. [PMID: 33153788 DOI: 10.1016/j.jhazmat.2020.124373] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 10/10/2020] [Accepted: 10/21/2020] [Indexed: 06/11/2023]
Abstract
In recent years, ultraviolet (UV) irradiation coupled with chlor(am)ination process is ubiquitous in secondary water supply systems in many cities of China. However, the disinfection by-products (DBPs) formation in a UV-activated mixed chlorine/chloramine system (MCCS) still remains unclear. In this study, the DBPs formation in a UV-activated MCCS was systematically investigated, considering influencing factors including the mass ratios of free chlorine to NH2Cl, UV irradiation, pH values, NOM types, Br- concentration and toxicity of the DBPs. Results indicated that DBPs formation decreased remarkably as mass ratio of free chlorine to NH2Cl changed from 5:0 to 0:5. The DBPs formation in humic acid (HA)-containing water was the highest, followed by those in fulvic acid (FA) and algal organic matter (AOM). Besides, better control of the DBP-related calculated toxicity can be achieved in acidic conditions regardless of the UV irradiation. Furthermore, in the presence of Br-, a significant reduction of DBPs formation could be achieved in a UV-activated MCCS. The findings also demonstrated that DBPs formation in real water can be effectively reduced at high UV fluence in a MCCS.
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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
| | - 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
| | - Yu-Lin Tang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Zheng-Yu Dong
- 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
| | - 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
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton AB T6G1H9, Canada
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265
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Ruan X, Xiang Y, Shang C, Cheng S, Liu J, Hao Z, Yang X. Molecular characterization of transformation and halogenation of natural organic matter during the UV/chlorine AOP using FT-ICR mass spectrometry. J Environ Sci (China) 2021; 102:24-36. [PMID: 33637249 DOI: 10.1016/j.jes.2020.08.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 08/18/2020] [Accepted: 08/30/2020] [Indexed: 06/12/2023]
Abstract
UV/chlorine process, as an emerging advanced oxidation process (AOP), was effective for removing micro-pollutants via various reactive radicals, but it also led to the changes of natural organic matter (NOM) and formation of disinfection byproducts (DBPs). By using negative ion electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS), the transformation of Suwannee River NOM (SRNOM) and the formation of chlorinated DBPs (Cl-DBPs) in the UV/chlorine AOP and subsequent post-chlorination were tracked and compared with dark chlorination. In comparison to dark chlorination, the involvement of ClO•, Cl•, and HO• in the UV/chlorine AOP promoted the transformation of NOM by removing the compounds owning higher aromaticity (AImod) value and DBE (double-bond equivalence)/C ratio and causing the decrease in the proportion of aromatic compounds. Meanwhile, more compounds which contained only C, H, O, N atoms (CHON) were observed after the UV/chlorine AOP compared with dark chlorination via photolysis of organic chloramines or radical reactions. A total of 833 compounds contained C, H, O, Cl atoms (CHOCl) were observed after the UV/chlorine AOP, higher than 789 CHOCl compounds in dark chlorination, and one-chlorine-containing components were the dominant species. The different products from chlorine substitution reactions (SR) and addition reactions (AR) suggested that SR often occurred in the precursors owning higher H/C ratio and AR often occurred in the precursors owning higher aromaticity. Post-chlorination further caused the cleavages of NOM structures into small molecular weight compounds, removed CHON compounds and enhanced the formation of Cl-DBPs. The results provide information about NOM transformation and Cl-DBPs formation at molecular levels in the UV/chlorine AOP.
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Affiliation(s)
- Xiaoxue Ruan
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Yingying Xiang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, 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, Hong Kong, China
| | - Shuangshuang Cheng
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Jingfu Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhineng Hao
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Xin Yang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China.
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266
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Lee JY, Lee YM, Kim TK, Choi K, Zoh KD. Degradation of cyclophosphamide during UV/chlorine reaction: Kinetics, byproducts, and their toxicity. CHEMOSPHERE 2021; 268:128817. [PMID: 33162158 DOI: 10.1016/j.chemosphere.2020.128817] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/13/2020] [Accepted: 10/27/2020] [Indexed: 06/11/2023]
Abstract
Cyclophosphamide (CP) is a widely used anticancer drug and an immunosuppressant. Since CP is nonbiodegradable, it is hardly removed by the conventional wastewater treatment processes, resulting in continuous detection in surface water. In this study, the degradation of CP during the UV-B/chlorine reaction was investigated. CP was not degraded by UV-B photolysis and chlorination only but was effectively degraded in the UV-B/chlorine reaction with pseudo-first-order kinetics. Acidic pH conditions in the UV-B/chlorine reaction showed the most effective removal of CP. More than 56% of the CP was mineralized within 8 h of the reaction. Seven organic transformation products (TPs) (m/z = 141.01, 192.10, 198.03, 212.01, 258.01, 274.00, and 276.02, respectively) and four inorganic byproducts (NH4+, NO3-, HCOO-, and PO43-) were identified using LC-qTOF/MS and ion chromatography, respectively. Microtox test based on bioluminescence inhibition showed that the toxicity inhibition increased to 88% as the reaction proceeded during the UV/chlorine reaction, probably due to the production of TPs, especially TP 258 (m/z = 258.01). The results of this study imply that the toxicity of TPs needs to be reduced when applying a UV-B/chlorination process to treat CP in water.
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Affiliation(s)
- Ji-Young Lee
- Department of Environmental Health Sciences, School of Public Health, Seoul National University, Seoul, South Korea
| | - Young-Min Lee
- Institute of Health and Environment, Seoul National University, Seoul, South Korea
| | - Tae-Kyoung Kim
- Environmental Fate and Exposure Research Group, Korea Institute of Toxicology, Jinju, South Korea
| | - Kyungho Choi
- Department of Environmental Health Sciences, School of Public Health, Seoul National University, Seoul, South Korea; Institute of Health and Environment, Seoul National University, Seoul, South Korea
| | - Kyung-Duk Zoh
- Department of Environmental Health Sciences, School of Public Health, Seoul National University, Seoul, South Korea; Institute of Health and Environment, Seoul National University, Seoul, South Korea.
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267
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Han M, Jafarikojour M, Mohseni M. The impact of chloride and chlorine radical on nitrite formation during vacuum UV photolysis of water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 760:143325. [PMID: 33221016 DOI: 10.1016/j.scitotenv.2020.143325] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/07/2020] [Accepted: 10/19/2020] [Indexed: 06/11/2023]
Abstract
The impact of chloride ion and chlorine radical on the formation of nitrite was investigated under Vacuum-UV (VUV) photolysis of nitrate contaminating water. An increase in chloride concentration reduced nitrite formation in part due to the relatively high VUV absorption of chloride. The use of various radical scavengers, such as acetate and acetone, helped delineate the specific roles of hydroxyl radical (HO) and chlorine radical (Cl) in oxidation and VUV photolysis of nitrate, and the subsequent formation of nitrite. HO reduced nitrite formation due to its high reaction rate constant with nitrite. Nitrite formation in both chloride and dissolved organic carbon (DOC) containing solution depended primarily on their relative concentrations. Carbamazepine (CBZ) was also used to analyze the effect of Cl on both the degradation of CBZ and the formation of nitrite. Cl showed to significantly increase the degradation of CBZ, but it had little impact on the formation of nitrite. This paper, utilizing detailed experimental data combined with kinetic modeling and mechanistic analysis of VUV photolysis in the presence of chloride and nitrate, provides the necessary scientific guidance towards more effective and optimized applications of VUV technology for drinking water treatment.
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Affiliation(s)
- Mengqi Han
- Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada
| | - Morteza Jafarikojour
- Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada
| | - Madjid Mohseni
- Department of Chemical and Biological Engineering, University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada.
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268
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Zhou Y, Cheng F, He D, Zhang YN, Qu J, Yang X, Chen J, Peijnenburg WJGM. Effect of UV/chlorine treatment on photophysical and photochemical properties of dissolved organic matter. WATER RESEARCH 2021; 192:116857. [PMID: 33517044 DOI: 10.1016/j.watres.2021.116857] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 01/15/2021] [Accepted: 01/17/2021] [Indexed: 06/12/2023]
Abstract
Dissolved organic matter (DOM) is a ubiquitous component in effluents, DOM discharged with an effluent can affect the composition and properties of natural DOM in the receiving waters. As the photophysical and photochemical properties of effluent DOM can be changed by wastewater treatment processes, the effect of UV/chlorine treatment on the photophysical and photochemical properties of DOM was investigated using Suwannee River fulvic acid (SRFA) and Suwannee River natural organic matter (SRNOM) as representatives. Results showed that the absorbance of the two DOM was significantly decreased. The evolution trends of three representative photophysical parameters upon increase of chlorine dosages were observed. Also, a decrease in DOM aromaticity, molecular weight and electron-donating capacity was observed upon increasing chlorine dosage. Quantum yields of excited triplet state of DOM (3DOM*), singlet oxygen (1O2) and hydroxyl radicals (·OH) first decreases and then increased in the UV/chlorine systems upon increasing chlorine dosages due to the different reaction pathways of the two DOM. Moreover, 3DOM* can not only be regarded as a "controller" of other reactive intermediates, but also effectively promote the photodegradation of bezafibrate, which is classified as a persistent organic contaminant. This study gives deep insights into effects of UV/chlorine on the photophysical and photochemical properties of DOM, and is helpful for understanding the dynamic roles of DOM in the photodegradation of micropollutants.
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Affiliation(s)
- Yangjian Zhou
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China; School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Fangyuan Cheng
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China
| | - Dongyang He
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China
| | - Ya-Nan Zhang
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Jiao Qu
- State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
| | - Xin Yang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Jingwen Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Willie J G M Peijnenburg
- Institute of Environmental Sciences, Leiden University, Leiden, the Netherlands; National Institute of Public Health and the Environment (RIVM), Center for Safety of Substances and Products, Bilthoven, the Netherlands
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269
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Yang T, Mai J, Wu S, Liu C, Tang L, Mo Z, Zhang M, Guo L, Liu M, Ma J. UV/chlorine process for degradation of benzothiazole and benzotriazole in water: Efficiency, mechanism and toxicity evaluation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 760:144304. [PMID: 33341627 DOI: 10.1016/j.scitotenv.2020.144304] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 10/30/2020] [Accepted: 11/27/2020] [Indexed: 06/12/2023]
Abstract
Benzothiazole (BZA) and benzotriazole (BTZ) as emerging contaminants were found persistent in aquatic environments and toxic to aquatic organisms. The degradation of BZA and BTZ by UV/chlorine was systematically investigated in this study, and the results showed that BZA and BTZ can be remarkably removed by UV/chlorine compared with UV alone and dark chlorination. The radical quenching tests showed that degradation of BZA and BTZ by UV/chlorine involved the participation of reactive chlorine species (RCS), hydroxyl radical (HO·), and UV photolysis. HO· dominated BZA degradation at neutral and alkalinity, while RCS dominated BTZ degradation. The second-rate order constants for ClO· and BZA and BTZ were 2.22 × 108 M-1 s-1, and 2.40 × 108 M-1 s-1, respectively. Besides, the second-order rate constants for HO· and BZA and BTZ were also determined at pH 5.0, 7.0, and 9.0, respectively. The degradation efficiency of BZA by UV/chlorine was substantially promoted at acidic conditions, while the degradation efficiency of BTZ was promoted at both acidic and specific alkaline range mainly due to the reactivity of radical species and deprotonated form. The influence of Cl- was negligible, but the suppression effect of humic acid was slight during the BZA and BZT degradation by UV/chlorine. The transformation products were detected and the possible pathways were proposed. Seven disinfection by-products (DBPs) were identified both in BZA and BTZ degradation and trichloromethane was the main DBP. The toxicity assessment performed by luminescent bacteria and ECOSAR analysis indicated that the detoxification of BZA could be achieved by UV/chlorine, whereas the toxicity of BTZ was increased mainly due to the formation of intermediates. The findings from this study demonstrated UV/chlorine is likewise efficient for BZA and BTZ removal but the toxicity should be considered in the BTZ degradation.
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Affiliation(s)
- Tao Yang
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Jiamin Mai
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Sisi Wu
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Chunping Liu
- Department of Cardiovascular Medicine, Guangdong Hospital of Traditional Chinese Medicine, Guangzhou, China
| | - Liuyan Tang
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Zongwen Mo
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Mengchen Zhang
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Lin Guo
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China
| | - Minchao Liu
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, Guangdong Province, China.
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environmental, Harbin Institute of Technology, Harbin 150090, China.
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270
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Chen T, Yu Z, Xu T, Xiao R, Chu W, Yin D. Formation and degradation mechanisms of CX 3R-type oxidation by-products during cobalt catalyzed peroxymonosulfate oxidation: The roles of Co 3+ and SO 4·. JOURNAL OF HAZARDOUS MATERIALS 2021; 405:124243. [PMID: 33109408 DOI: 10.1016/j.jhazmat.2020.124243] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 10/07/2020] [Accepted: 10/08/2020] [Indexed: 06/11/2023]
Abstract
Sulfate radical (SO4·-)-based advanced oxidation processes (AOPs) attract increasing attention in the control of micropollutants. However, SO4·- can react with other chemicals present in water and result in undesired oxidation by-products (OBPs) generation. The formation and degradation mechanisms of CX3R-type OBPs during cobalt catalyzed peroxymonosulfate (Co2+/PMS) oxidation were investigated. In the formation of CX3R-type OBPs, both Co3+ and SO4·- could convert chloride to free chlorine that then reacted with natural organic matter, leading to the formation of CX3R-type OBPs. The concentrations of trichloromethane, chloral hydrate, dichloroacetonitrile, dichloroacetamide and trichloroacetamide after 15 min reaction were 9.8, 3.9, 1.2, 5.9 and 22.3 nM, respectively. Compared to SO4·-, Co3+ played a more significant role in the CX3R-type OBP formation and calculated toxicity values of CX3R-type OBPs. CX3R-type OBPs could not only be formed but also be degraded at the same time during Co2+/PMS oxidation. As for the degradation of CX3R-type OBPs, both Co3+ and SO4·- could transform CX3R-type OBPs to chloride. Compared to Co3+, SO4·- played a more important role in the degradation of CX3R-type OBPs and the conversion from chloride to final by-product chlorate. The adverse effects that results from Co3+ need more attention in SO4·--based AOPs application.
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Affiliation(s)
- Tiantian Chen
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Zhenyang Yu
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Ting Xu
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Rong Xiao
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China
| | - Wenhai Chu
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
| | - Daqiang Yin
- State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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271
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Djaballah ML, Merouani S, Bendjama H, Hamdaoui O. Development of a free radical-based kinetics model for the oxidative degradation of chlorazol black in aqueous solution using periodate photoactivated process. J Photochem Photobiol A Chem 2021. [DOI: 10.1016/j.jphotochem.2020.113102] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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272
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Wang P, Bu L, Wu Y, Ma W, Zhu S, Zhou S. Mechanistic insight into the degradation of ibuprofen in UV/H 2O 2 process via a combined experimental and DFT study. CHEMOSPHERE 2021; 267:128883. [PMID: 33183784 DOI: 10.1016/j.chemosphere.2020.128883] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 11/01/2020] [Accepted: 11/04/2020] [Indexed: 06/11/2023]
Abstract
The study investigated the degradation kinetic and transformation mechanism of ibuprofen (IBP) in UV/H2O2 process from both experimental and theoretical aspects. Impacts of H2O2 dosage, solution pH, quenching agent, and concentration of nitrite (NO2-) on IBP degradation in UV/H2O2 process were evaluated. Both experimental results and theoretical calculations indicated that •OH played an important role in the degradation of IBP and its transformation products. The second-order rate constants of •OH and •NO2 with IBP were calculated as 3.93 × 109 M-1 s-1 and 5.59 × 10-3 M-1 s-1, based on the transition state theory, which explained the phenomenon that addition of NO2- inhibited IBP degradation. Further, according to the results of ultra-high-resolution mass and density functional theory calculations, mechanisms of a detailed degradation pathway for IBP were clarified. Namely, the detailed mechanistic formation pathways for hydroxylated and keto-based products were proposed. Then, possible active sites of the keto-based products, as well as the corresponding subsequent products were predicted by Condensed Fukui Function. Our study can broaden the knowledge of the reactions of emerging contaminants with •OH, and provide theoretical foundation for the optimization of UV/H2O2 process.
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Affiliation(s)
- Pin Wang
- Key Laboratory of Building Safety and Energy Eficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Lingjun Bu
- Key Laboratory of Building Safety and Energy Eficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China.
| | - Yangtao Wu
- Key Laboratory of Building Safety and Energy Eficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Wangchi Ma
- Key Laboratory of Building Safety and Energy Eficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Shumin Zhu
- Key Laboratory of Building Safety and Energy Eficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
| | - Shiqing Zhou
- Key Laboratory of Building Safety and Energy Eficiency, Ministry of Education, Department of Water Engineering and Science, College of Civil Engineering, Hunan University, Changsha, 410082, China
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273
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Zhang W, Zhou S, Wu Y, Zhu S, Crittenden J. Computerized Pathway Generator for the UV/Free Chlorine Process: Prediction of Byproducts and Reactions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:2608-2617. [PMID: 33522788 DOI: 10.1021/acs.est.0c07080] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The ultraviolet (UV)/free chlorine process is a very promising treatment technology to remove persistent organic contaminants (POCs, e.g., pharmaceutical and personal care products) from water. The radical chain reactions involved in the UV/free chlorine process are very complicated, and the reaction pathways for organic contaminants degradation are largely unknown. Therefore, we developed a computerized pathway generator that uses graph theory and experimentally determined reaction rules that were reported for the UV/free chlorine process. Our pathway generator predicts all possible intermediates, byproducts, and elementary reactions that are involved in the oxidation of organic contaminants. For example, the degradation of tricholoroethylene (TCE) produces 497 species (i.e., intermediates and byproducts) and 6608 elementary reactions. The predicted species from our pathway generator not only predict the major and stable byproducts that were observed in our experiments (e.g., CHCl2COOH, CHCl(OCl)COOH, etc.) but also include many other minor and toxic byproducts that were produced but not measured because they have a short lifetime. Overall, our pathway generator significantly improves our understanding of the reaction pathways that are involved in organic contaminant degradation in the UV/free chlorine process.
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Affiliation(s)
- Weiqiu Zhang
- School of Civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Shiqing Zhou
- School of Civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Yangtao Wu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - Shumin Zhu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha 410082, China
| | - John Crittenden
- School of Civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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274
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Wang J, Wu Y, Bu L, Zhu S, Zhang W, Zhou S, Gao N. Simultaneous removal of chlorite and contaminants of emerging concern under UV photolysis: Hydroxyl radicals vs. chlorate formation. WATER RESEARCH 2021; 190:116708. [PMID: 33279746 DOI: 10.1016/j.watres.2020.116708] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 11/23/2020] [Accepted: 11/28/2020] [Indexed: 06/12/2023]
Abstract
It is well known that using chlorine dioxide (ClO2) as a disinfectant inevitably produces a common disinfection byproducts chlorite (ClO2‒). In this study, we found that UV photolysis after ClO2 disinfection can effectively eliminate both ClO2‒ and contaminants of emerging concern (CECs). However, the kinetic mechanisms of UV/ClO2‒ process destructing CECs, as well as transformation of ClO2‒ in UV/ClO2‒ system are not clear yet. Therefore, we systematically investigated the UV/ClO2‒ system to assist us appropriately design this process under optimal operational conditions. In this work, we first investigated the impact of water matrix conditions (i.e., pH, bicarbonate and natural organic matter (NOM)) and ClO2‒ dosage on the UV/ClO2‒ process. We found that bicarbonate and NOM have inhibition effects, while lower pH and higher ClO2‒ dosage have enhancement effects. Besides, hydroxyl radical (HO•) and reactive chlorine species (RCS) are generated from UV/ClO2‒ system, and RCS are main contributors to CBZ degradation. Then we proposed a possible degradation pathway of CBZ based on the determined products from experiments. Additionally, we found that photolysis of ClO2‒ resulted in the generation of chloride (Cl‒) and chlorate (ClO3‒). As the ClO2‒ dosage increases, the yield of ClO3‒ increased while that of Cl‒ decreased. Finally, we elucidated the second order rate constant of the target organic compound with HO• has a strong correlation with the formation of ClO3‒.
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Affiliation(s)
- Jue Wang
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, PR China
| | - Yangtao Wu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, PR China
| | - Lingjun Bu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, PR China
| | - Shumin Zhu
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, PR China
| | - Weiqiu Zhang
- Brook Byer Institute for Sustainable Systems and School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Shiqing Zhou
- Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, College of Civil Engineering, Hunan University, Changsha, Hunan, 410082, PR China.
| | - Naiyun Gao
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China
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275
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Yang P, Li D, Zhang W, Ai J, Peng S, Wang D, Cui F. Study of sludge conditioning using organic acids chelated ferrous ion catalyzed NaClO oxidation: Evolution of extracellular polymeric substances and floc structure. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 280:111757. [PMID: 33298393 DOI: 10.1016/j.jenvman.2020.111757] [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: 05/08/2020] [Revised: 11/10/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
In previous studies, we interestingly found that several ligands (e.g., nitrilotriacetate and humic acid) could significantly accelerate the oxidation of NaClO by ferrous ion, via complexing with Fe(II). This inspired us to hypothesis that organic acids (OA) chelated Fe(II) might enhance the NaClO oxidation for improving sludge dewaterability. In this work, the OA chelated ferrous ions activated NaClO (OA-Fe(II)-NaClO) process was utilized for sludge conditioning, which exhibited significantly improved dewatering performance, as evidenced by capillary suction time (CST), specific resistance to filtration (SRF) and cake moisture of sludge. The normalized CST (CSTn) and SRF decreased to 1.22 s × L/g and 3.24 × 108 m/kg, when ratio dosage of [ClO-]/[Fe2+] (NaClO: 0.75%(v/v)) was 1 at pH of 2. During the NaClO activation by Fe(II), tightly bound extracellular polymeric substances (TB-EPS) was cracked into soluble EPS (S-EPS), followed by oxidizing into smaller molecular organic matters due to the production of hydroxyl radicals. Meanwhile, OA complexed to ferrous ion inhibited hydrolysis of ferric ions, leading to better catalytic performance of NaClO under neutral pH conditions. In addition, the molecular structure of OA determined the low complexing ability and steric hindrance for OA-Fe(II). When molar ratio of [Oxalic acid]/[Fe2+] was 1, oxalic acid-Fe(II)-NaClO improved sludge dewaterability significantly due to the coagulation and skeleton builder properties of formed iron oxalate precipitates. This work provides an eco-friendly and cost-effective method for improving sludge dewaterability.
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Affiliation(s)
- Peng Yang
- School of Civil Engineering and Architecture, Northeast Electric Power University, Jilin, 132012, Jilin, China; School of Environmental Studies, China University of Geosciences, Wuhan, 430074, Hubei, China
| | - Dandan Li
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, Hubei, China
| | - Weijun Zhang
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, Hubei, China.
| | - Jing Ai
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, Hubei, China
| | - Sainan Peng
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, Hubei, China
| | - Dongsheng Wang
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, Hubei, China
| | - Fengguo Cui
- School of Civil Engineering and Architecture, Northeast Electric Power University, Jilin, 132012, Jilin, China
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276
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Zhao J, Shang C, Zhang X, Yang X, Yin R. The multiple roles of chlorite on the concentrations of radicals and ozone and formation of chlorate during UV photolysis of free chlorine. WATER RESEARCH 2021; 190:116680. [PMID: 33285457 DOI: 10.1016/j.watres.2020.116680] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/08/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Chlorine dioxide (ClO2) has emerged as a promising alternative to free chlorine for water disinfection and/or pre-oxidation due to its reduced yields of chlorinated disinfection byproducts. ClO2 decomposes to form chlorite (ClO2-), which influences the following advanced oxidation processes (AOPs) for micropollutant abatement in drinking water. This study aims at investigating the effects of ClO2- on the concentrations of reactive species (e.g., radicals and ozone) and on the formation of chlorate in the UV/chlorine AOP. Results showed that the concentration of ClO· in the UV/chlorine process remarkably decreased by 98.20-100.00% in the presence of ClO2- at concentration of 0.1-1.0 mg·L-1 as NaClO2. The concentrations of HO· and ozone decreased by 42.71-65.42% and by 22.02-64.31%, respectively, while the concentration of Cl· was less affected (i.e., 31.00-36.21% reduction). The overall concentrations of the reactive species were differentially impacted by ClO2-'s multiple roles in the process. UV photolysis of ClO2- generated HO· but not Cl·, ClO· or ozone under the drinking water relevant conditions. ClO2- also competed with chlorine for UV photons but this effect was minor (< 1.0%). The radicals/ozone scavenging by ClO2- outcompeted the above two to lead to the overall decreasing concentrations of the reactive species, in consistency with the kinetic model predicted trends. ClO2- reacted with radicals and ozone to form chlorate (ClO3-) but not perchlorate (ClO4-). HO· played a dominant role in ClO3- formation. The findings improved the fundamental understanding on micropollutant abatement and inorganic byproduct formation by the UV/chlorine process and other AOPs in ClO2--containing water.
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Affiliation(s)
- Jing Zhao
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong; Hong Kong Branch of Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
| | - Xinran Zhang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xin Yang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, China.
| | - Ran Yin
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
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277
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Phattarapattamawong S, Chareewan N, Polprasert C. Comparative removal of two antibiotic resistant bacteria and genes by the simultaneous use of chlorine and UV irradiation (UV/chlorine): Influence of free radicals on gene degradation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 755:142696. [PMID: 33059146 DOI: 10.1016/j.scitotenv.2020.142696] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/12/2020] [Accepted: 09/27/2020] [Indexed: 06/11/2023]
Abstract
The research aimed to remove antibiotic resistance by the simultaneous use of UV irradiation and chlorine (UV/chlorine). The inactivations of tetracycline resistant bacteria (TRB) during chlorination, UV irradiation, and UV/chlorine was investigated and compared with those of amoxicillin resistant bacteria (AmRB). Similar examination was also conducted for comparing the removals of their resistant genes (i.e., tetM and blaTem). The removals of antibiotic resistance highly depended on chlorine doses and UV intensities. The sufficient chlorine dose (20 mg.L-1) in the chlorination and the UV/chlorine completely inactivated TRB and AmRB (>7.3 log), while the UV irradiation could not achieve the complete disinfection. Microorganisms resistant to different antibiotics exhibit different susceptibility to the disinfection processes. The removals of antibiotic resistant genes (i.e., tetM and blaTem) were more difficult than those of TRB and AmRB. The UV/chlorine was the greatest process for tetM and blaTem removals, followed by chlorination and UV irradiation, respectively. Chlorination decreased the tetM and blaTem by 0.40-1.45 log and 1.04-2.45 log, respectively. The blaTem gene was highly reactive to chlorine, compared with tetM. The UV irradiation caused the tetM and blaTem reductions by 0.32-0.91 log and 0.59-0.96 log, respectively. The UV/chlorine improved the tetM and blaTem removals by 0.98-3.20 log and 1.28-3.36 log, respectively. The •OH contributed to the fraction of tetM and blaTem removals by 48% and 19%, respectively. The effect of reactive chlorine species on the tetM and blaTem removals was minor. The pseudo 1st-order kinetic constants (k') for tetM and blaTem removals by the UV/chlorine were highest. The •OH enhanced the k' values by 120% and 20% for the tetM and blaTem removals, respectively. The study showed the potential use of UV/chlorine for controlling antibiotic resistance.
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Affiliation(s)
- Songkeart Phattarapattamawong
- Department of Environmental Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi (KMUTT), Thailand; Center of Excellence on Hazardous Substance Management (HSM), Thailand.
| | - Narissara Chareewan
- Department of Environmental Engineering, Faculty of Engineering, King Mongkut's University of Technology Thonburi (KMUTT), Thailand
| | - Chongrak Polprasert
- Department of Civil Engineering, Faculty of Engineering, Thammasat University, Thailand
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278
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Lee YM, Lee G, Zoh KD. Benzophenone-3 degradation via UV/H 2O 2 and UV/persulfate reactions. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123591. [PMID: 32795823 DOI: 10.1016/j.jhazmat.2020.123591] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 07/13/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
The degradation of benzophenone-3 (BP3) in water via the UV/H2O2 and UV/persulfate (UV/PS) reactions was investigated. The degradation of BP3 exhibited pseudo-first-order kinetics in both reactions. The degradation efficiency of BP3 was higher in the UV/PS reaction than in the UV/H2O2 reaction. In both reactions, the observed rate constants (kobs) of BP3 degradation were highest at pH 6 and increased linearly with increasing dosage of H2O2 and persulfate. The second-order rate constants of BP3 with •OH (k•OH_BP3) and •SO4- (k•SO4-_BP3) were determined to be 1.09 (± 0.05) × 1010 and 1.67 (± 0.04) × 109 M-1 s-1, respectively. The kobs values of BP3 were affected by water components such as HCO3-, NO3-, Cl-, and Br- ions, as well as humic acid. Based on the identified transformation products (TPs), the degradation pathway of BP3 during both reactions was a hydroxylation reaction. The inhibition of bioluminescence in Vibrio fischeri due to BP3 and its TPs decreased more quickly in the UV/PS reaction than in the UV/H2O2 reaction. The results suggest that the UV/PS process is a better alternative to the UV/H2O2 process for removing BP3 and its toxicity in water.
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Affiliation(s)
- Young-Min Lee
- Institute of Health and Environment, Seoul National University, Seoul, South Korea
| | - Gowoon Lee
- Institute of Health and Environment, Seoul National University, Seoul, South Korea
| | - Kyung-Duk Zoh
- Department of Environmental Health Sciences, School of Public Health, Seoul National University, Seoul, South Korea.
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279
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Zhao N, Liu K, Yan B, Zhu L, Zhao C, Gao J, Ruan J, Zhang W, Qiu R. Chlortetracycline hydrochloride removal by different biochar/Fe composites: A comparative study. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123889. [PMID: 33264955 DOI: 10.1016/j.jhazmat.2020.123889] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/19/2020] [Accepted: 08/29/2020] [Indexed: 05/22/2023]
Abstract
In the last years, the synthesis and applications of biochar/Fe composites have been extensively studied, but only few papers have systematically evaluated their removal performances. Herein, we successfully synthesized and structurally characterized Fe0, Fe3C, and Fe3O4-coated biochars (BCs) for the removal of chlortetracycline hydrochloride (CH). Evaluation of their removal rate and affinity revealed that Fe0@BC could achieve better and faster CH removal and degradation than Fe3C@BC and Fe3O4@BC. The removal rate was controlled by the O-Fe content and solution pH after the reaction. The CH adsorption occurred on the O C groups of Fe0@BC and the OC and OFe groups of Fe3C@BC and Fe3O4@BC. Electron paramagnetic resonance analysis and radical quenching experiments indicated that HO and 1O2/ O2- were mainly responsible for CH degradation by biochar/Fe composites. Additional parameters, such as effects of initial concentrations and coexisting anions, regeneration capacity, cost and actual wastewater treatment were also explored. Principal component analysis was applied for a comprehensive and quantitative assessment of the three materials, indicating Fe0@BC is the most beneficial functional material for CH removal.
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Affiliation(s)
- Nan Zhao
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, PR China; School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Kunyuan Liu
- School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Bofang Yan
- School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Ling Zhu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, PR China
| | - Chuanfang Zhao
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China
| | - Jia Gao
- School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Jujun Ruan
- School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Weihua Zhang
- School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, PR China
| | - Rongliang Qiu
- Guangdong Laboratory for Lingnan Modern Agriculture, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, PR China; School of Environmental Science and Engineering, Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou, 510275, PR China.
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280
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Yang T, Wu S, Liu C, Liu Y, Zhang H, Cheng H, Wang L, Guo L, Li Y, Liu M, Ma J. Efficient Degradation of Organoarsenic by UV/Chlorine Treatment: Kinetics, Mechanism, Enhanced Arsenic Removal, and Cytotoxicity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:2037-2047. [PMID: 33435681 DOI: 10.1021/acs.est.0c05084] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Roxarsone (ROX) has been widely used as an organoarsenic additive in animal feeding operations and poses a risk to the environment. Here, we first report the efficient degradation of ROX by UV/chlorine, where the kinetics, removal of total arsenic (As), and cytotoxicity were investigated. The kinetics study presented that reactive chlorine species (RCS) and HO• were the dominant species to react with ROX. Furthermore, the degradation rate of ROX can reach the maximum value at pH 7.5 due to the formation of more RCS. The degradation of ROX was affected by the amount of chlorine, pH, and water matrix. Through product analysis and Gauss theoretical calculation, two possible ROX degradation pathways were proposed. The free radicals attacked the As-C bond of ROX and resulted in releasing arsenate (As(V)). It was the reason that for an enhancement of the removal of total As by ferrous appeared after UV/chlorine, and over 98% of the total As was removed. In addition, cytotoxicity studies indicated that the cytotoxicity significantly enhanced during the degradation of ROX by UV/chlorine. However, by combination of UV/chlorine and adsorption, cytotoxicity can be greatly eliminated, probably due to the removal of As(V) and chlorinated products. These results further demonstrated that UV/chlorine treatment could be an effective method for the control of the potential environmental risks posed by organoarsenic.
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Affiliation(s)
- Tao Yang
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Sisi Wu
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Chunping Liu
- Department of Cardiovascular Medicine, Guangdong Hospital of Traditional Chinese Medicine, Guangzhou 510120, China
| | - Yulei Liu
- Technology R&D Center for Environmental Engineering, Dongguan University of Technology, Dongguan 523808, China
| | - Haochen Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environmental, Harbin Institute of Technology, Harbin 150090, China
| | - Haijun Cheng
- State Key Laboratory of Urban Water Resource and Environment, School of Environmental, Harbin Institute of Technology, Harbin 150090, China
| | - Lu Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environmental, Harbin Institute of Technology, Harbin 150090, China
| | - Lin Guo
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Yuying Li
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Minchao Liu
- School of Biotechnology and Health Science, Wuyi University, Jiangmen 529020, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environmental, Harbin Institute of Technology, Harbin 150090, China
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281
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Dong F, Lin Q, Li C, He G, Deng Y. Impacts of pre-oxidation on the formation of disinfection byproducts from algal organic matter in subsequent chlor(am)ination: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 754:141955. [PMID: 32920386 DOI: 10.1016/j.scitotenv.2020.141955] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 08/21/2020] [Accepted: 08/22/2020] [Indexed: 06/11/2023]
Abstract
Algae cells and algal organic matter (AOM) present in algae impacted source water pose a serious threat to the safety of drinking water. Conventional water treatment processes poorly remove AOM that can transform to harmful disinfection byproducts (DBPs) during ensuing disinfection. This article offers a comprehensive review on the impacts of pre-oxidation on the formation of DBPs from AOM in subsequent chlor(am)ination. Various characterization techniques for algal cells and AOM are first overviewed with an effort to better understanding of correlation between the AOM properties and downstream DBP formation. Then, the present work reviews recent studies on application of different pre-oxidation technologies, such as chlor(am) ination, UV irradiation, ozonation, ferrate (VI), permanganate oxidation and UV-based advanced oxidation processes (AOPs), to remove algal cells and degrade AOM. Pre-oxidation can reduce the stability of algal cells and inactivate algal cells for promoting cell aggregation and thus favoring coagulation. Meanwhile, pre-oxidation can mitigate and degrade AOM into small molecular weight organic compounds to reduce DBP formation potential during subsequent chlor(am)ination. Finally, this review provides an overall evaluation on the applicability of different pre-oxidation processes, and identifies future research demands.
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Affiliation(s)
- Feilong Dong
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
| | - Qiufeng Lin
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, United States
| | - Cong Li
- School of Environment and Architecture, University of Shanghai for Science and Technology, Shanghai 200433, China.
| | - Guilin He
- School of Municipal and Environmental Engineering, Shandong Jianzhu University, China
| | - Yang Deng
- Department of Earth and Environmental Studies, Montclair State University, Montclair, NJ 07043, United States
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282
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Cao Y, Qiu W, Li J, Zhao Y, Jiang J, Pang S. Sulfite enhanced transformation of iopamidol by UV photolysis in the presence of oxygen: Role of oxysulfur radicals. WATER RESEARCH 2021; 189:116625. [PMID: 33227612 DOI: 10.1016/j.watres.2020.116625] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 10/09/2020] [Accepted: 11/07/2020] [Indexed: 06/11/2023]
Abstract
UV/sulfite process in the absence of oxygen was previously applied as an advanced reduction process for the removal of many halogenated organics and inorganics in water and wastewater. Here, it was found that UV/sulfite process in the presence of oxygen could act as an advanced oxidation process. Specifically, the oxysulfur radicals (including sulfate radical (SO4·-) and sulfite/peroxomonosulfate radicals (SO3·-/SO5·-)) played important roles on the degradation of iopamidol (IPM) as a typical iodinated contrast media (ICM). Furthermore, the contribution of SO4·- on IPM removal gradually increased as pH increased from 5 to 7 and that of SO3·-/SO5·- decreased. Besides, all water quality parameters (i.e., chloride (Cl-), iodide (I-) and natural organic matter (NOM)) investigated here exhibited inhibitory effect on IPM removal. Three inorganic iodine species (i.e., I-, reactive iodine species and iodate (IO3-)) were detected in UV/sulfite process in the presence of oxygen, while only I- was detected in that without oxygen. During UV/sulfite/ethanol, UV photolysis and UV/peroxydisulfate (PDS)/tert-butyl alcohol (TBA) processes, thirteen transformation products including eleven deiodinated products of IPM were identified by ultra HPLC quadrupole time of flight-mass spectrometry (UPLC-Q-TOF-MS). Besides, these products generated by direct UV photolysis, SO4·- and SO3·-/SO5·- were further distinguished. The acute toxicity assay of Vibrio fischeri indicated that transformation products by UV/sulfite under aerobic conditions were less toxic than that by direct UV photolysis.
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Affiliation(s)
- Ying Cao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Wei Qiu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Juan Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yumeng Zhao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jin Jiang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458, China.
| | - Suyan Pang
- Key Laboratory of Songliao Aquatic Environment, Ministry of Education, School of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun, 130118, China
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283
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Ding J, Nie H, Wang S, Chen Y, Wan Y, Wang J, Xiao H, Yue S, Ma J, Xie P. Transformation of acetaminophen in solution containing both peroxymonosulfate and chlorine: Performance, mechanism, and disinfection by-product formation. WATER RESEARCH 2021; 189:116605. [PMID: 33189970 DOI: 10.1016/j.watres.2020.116605] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 11/02/2020] [Accepted: 11/04/2020] [Indexed: 06/11/2023]
Abstract
With the fast development of peroxymonosulfate (PMS)-dominating processes in drinking water and wastewater treatment, residual PMS is easy to come across chlorine as these processes are usually followed by secondary chlorine disinfection. The synergistic effect of PMS and chlorine on the degradation of micro-organic pollutants is investigated by selecting acetaminophen (ACT) as a reference compound for the first time in this study. Unlike conventional PMS or chlorine activation which generates reactive species such as hydroxyl radical (HO•), sulfate radical (SO4•-), chlorine radical (Cl•), and singlet oxygen (1O2), the efficient ACT removal is attributed to the direct catalytic chlorination by PMS due to the significantly enhanced consumption of chlorine along with negligible change of PMS concentration at neutral condition, and the same reaction pathways in both PMS/chlorine and chlorine processes. The kinetic study demonstrates that ACT oxidation by PMS/chlorine follows second order reaction, and the degradation efficiency can be promoted at alkaline conditions with peak rate constants at pH 9.0-10.0. The presence of chloride can enhance the removal of ACT, while ammonium and humic acid significantly retard ACT degradation. Higher formation of selected disinfection by-products (DBPs) is observed in the PMS/chlorine process than in the sole chlorination. This study highlights the important role of PMS in organic pollutants degradation and DBPs formation during the chlorination process.
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Affiliation(s)
- Jiaqi Ding
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Hui Nie
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Songlin Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yongsheng Chen
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Ying Wan
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Jingwen Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Haoliang Xiao
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Siyang Yue
- School of Architecture & Urban Planning, Huazhong University of Science and Technology (HUST), Wuhan 430074, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Pengchao Xie
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China; Center for the Environmental Implications of Nanotechnology (CEINT), Duke University, Durham 27708-0287, USA.
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284
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Parvizi T, Parsa JB, Farnood R. Highly-efficient degradation of organic pollutants and synchronous electricity generation in a photocatalytic fuel cell based on the catalytic reactions of hydroxyl and chlorine radicals. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.137753] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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285
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Abdalrhman AS, Wang C, How ZT, Gamal El-Din M. Degradation of cyclohexanecarboxylic acid as a model naphthenic acid by the UV/chlorine process: Kinetics and by-products identification. JOURNAL OF HAZARDOUS MATERIALS 2021; 402:123476. [PMID: 32711384 DOI: 10.1016/j.jhazmat.2020.123476] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/29/2020] [Accepted: 07/11/2020] [Indexed: 06/11/2023]
Abstract
Degradation kinetics, by-products identification and pathways of a model naphthenic acid, cyclohexanecarboxylic acid (CHA), by the UV/Chlorine process were investigated in this study. Mathematical modeling indicated that the initial CHA decay rate increased rapidly with the chlorine dose when the chlorine dose was lower than 45 mg/L and decreased with further chlorine dose increases. Increasing the chlorine dose from 400 to 800 mg/L resulted in a steady increase in the total removal of CHA after 60 min of UV photolysis. By dividing the 700 mg/L chlorine dose into five separated doses (140 mg/L each) added at 10 min intervals, the total CHA removal increased from 72% to 91%. This implies that the ideal condition of the UV/Chlorine process in degrading CHA is to add chlorine continuously at a constant rate to compensate any chlorine consumption to reduce the radical scavenging effect. It was found that the CHA decay was mainly attributed to the hydroxyl radical (OH) attack and the reactive chlorine species (RCS) contribution was relatively small. Various by-products, including the mono-chlorinated and di-chlorinated by-products, were identified and the reaction pathway for CHA degradation during UV/Chlorine treatment was proposed.
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Affiliation(s)
- Abdallatif Satti Abdalrhman
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada; Department of Civil and Mineral Engineering, University of Toronto, 35 St. George Street, Toronto, ON, M5S 1A4, Canada
| | - Chengjin Wang
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada; Department of Civil and Mineral Engineering, University of Toronto, 35 St. George Street, Toronto, ON, M5S 1A4, Canada
| | - Zuo Tong How
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada
| | - Mohamed Gamal El-Din
- Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada.
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286
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Dong Y, Peng W, Liu Y, Wang Z. Photochemical origin of reactive radicals and halogenated organic substances in natural waters: A review. JOURNAL OF HAZARDOUS MATERIALS 2021; 401:123884. [PMID: 33113752 DOI: 10.1016/j.jhazmat.2020.123884] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 08/14/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
Halogenated organic compounds, also termed organohalogens, were initially regarded to be of almost exclusively anthropogenic origin. However, recent research has demonstrated that photochemical reactions are important abiotic sources of organohalogen compounds in sunlit surface waters. Halide ions (X-, X represents Cl, Br and I) are common anions in natural waters and might be oxidized by reactive species originated from photochemistry of dissolved organic matter (DOM) or inorganic photoactive species. The resulting reactive halogen species may react with organic substances with diverse bimolecular reaction rate constants, depending on the complexity and structure of organic substances. Therefore, the chemical mechanism of halogenation remains challenging to be fully elucidated. To better understand the trends in the existing data and to identify the knowledge gaps that may merit further investigation, this review gives an integrative summary on the sources of reactive oxygen species (ROS) and halogen radicals (X/X2-). Photochemical halogenation of phenolic compounds and formation of methyl halide and brominated organic pollutants are highlighted. By evaluating existing literature and identifying some uncertainties, this review emphasizes the environmental significance of sunlight-driven halogenation and proposes further research directions on mechanistic investigation and rational experimental design close to natural systems.
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Affiliation(s)
- Yongxia Dong
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Wenya Peng
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Yunjiao Liu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Zhaohui Wang
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, Shanghai 200241, China; Technology Innovation Center for Land Spatial Eco-restoration in Metropolitan Area, Ministry of Natural Resources, 3663 N. Zhongshan Road, Shanghai 200062, China.
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287
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Lei Y, Lei X, Westerhoff P, Zhang X, Yang X. Reactivity of Chlorine Radicals (Cl • and Cl 2•-) with Dissolved Organic Matter and the Formation of Chlorinated Byproducts. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:689-699. [PMID: 33346661 DOI: 10.1021/acs.est.0c05596] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Chlorine radicals, including Cl• and Cl2•-, can be produced in sunlight waters (rivers, oceans, and lakes) or water treatment processes (e.g., electrochemical and advanced oxidation processes). Dissolved organic matter (DOM) is a major reactant with, or a scavenger of, Cl• and Cl2•- in water, but limited quantitative information exists regarding the influence of DOM structure on its reactivity with Cl• and Cl2•-. This study aimed at quantifying the reaction rates and the formation of chlorinated organic byproducts produced from Cl• and Cl2•- reactions with DOM. Laser flash photolysis experiments were conducted to quantify the second-order reaction rate constants of 19 DOM isolates with Cl• (kDOM-Cl•) and Cl2•- (kDOM-Cl2•-), and compare those with the hydroxyl radical rate constants (kDOM-•OH). The values for kDOM-Cl• ((3.71 ± 0.34) × 108 to (1.52 ± 1.56) × 109 MC-1 s-1) were orders of magnitude greater than the kDOM-Cl2•- values ((4.60 ± 0.90) × 106 to (3.57 ± 0.53) × 107 MC-1 s-1). kDOM-Cl• negatively correlated with the weight-averaged molecular weight (MW) due to the diffusion-controlled reactions. DOM with high aromaticity and total antioxidant capacity tended to react faster with Cl2•-. During the same experiments, we also monitored the formation of chlorinated byproducts through the evolution of total organic chlorine (TOCl) as a function of chlorine radical oxidant exposure (CT value). Maximum TOCl occurred at a CT of 4-8 × 10-12 M·s for Cl• and 1.1-2.2 × 10-10 M·s for Cl2•-. These results signify the importance of DOM in scavenging chlorine radicals and the potential risks of producing chlorinated byproducts of unknown toxicity.
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Affiliation(s)
- Yu Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Xin Lei
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Paul Westerhoff
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona 85287-3005, United States
| | - Xinran Zhang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Xin Yang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, China
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288
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Zhang X, Chen Z, Kang J, Zhao S, Wang B, Yan P, Deng F, Shen J, Chu W. UV/ peroxymonosulfate process for degradation of chloral hydrate: Pathway and the role of radicals. JOURNAL OF HAZARDOUS MATERIALS 2021; 401:123837. [PMID: 33113746 DOI: 10.1016/j.jhazmat.2020.123837] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 08/27/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
In this study, kinetics, influencing factors and potential mechanisms involved in the degradation of chloral hydrate (CH) by UV/peroxymonosulfate (PMS) process were demonstrated. The degradation rate of CH could reach 89.6% by UV254/PMS process, significantly exceeding UV300/PMS (0.7%), UV350/PMS (6.3%), UV254 direct photolysis (9.0%) and PMS alone (0.0%) processes. CH degradation in UV254/PMS system followed pseudo first-order degradation kinetics with an apparent rate constant of 0.186 min-1, which was suppressed by Cl- and HCO3-. The optimal pH for CH degradation was around 5.0. Direct mineralization accounted for the CH degradation in UV/PMS system. Interestingly, the addition of PMS at the neutral condition before UV irradiation transferred CH into trichloroacetic acid (TCAA). The transformation efficiency of CH into TCAA at 10 min was enhanced from 2.17%-40.38% with the elevation of initial pH from 7.0-8.0. The subsequent exposure of UV lamps ceased the transformation of CH into TCAA and facilitated the direct mineralization of CH, but it did not work in the refractory TCAA degradation. Finally, it was revealed that HO predominantly participated CH degradation in UV/PMS process, while O2- was responsible for the transformation of CH into TCAA by addition of PMS before UV irradiation.
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Affiliation(s)
- Xiaoxiao Zhang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China; Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Zhonglin Chen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jing Kang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Shengxin Zhao
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Binyuan Wang
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Pengwei Yan
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Fengxia Deng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jimin Shen
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Wei Chu
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
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289
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Zhang X, Wei D, Yu Q, Du Y. Characterization of UV and chlorine contributions to transformation of 2,3,4-trihydroxybenzophenone under combined UV-chlorine treatment. CHEMOSPHERE 2021; 263:128310. [PMID: 33297246 DOI: 10.1016/j.chemosphere.2020.128310] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/07/2020] [Accepted: 09/09/2020] [Indexed: 06/12/2023]
Abstract
Combined UV-chlorine treatment is a promising disinfection technology providing synergistic effects on bacteria-killing. The interaction between UV and chlorine would affect pollutants removal and disinfection by-products formation, while little is known about how UV and chlorine respectively contribute to pollutants transformation under combined UV-chlorine treatment. In this study, UV filter 2,3,4-trihydroxybenzophenone (2,3,4-THBP) was selected as a model compound to investigate the transformation characteristics and acute toxicity variation under combined UV-chlorine treatment. Especially, separative UV and chlorination treatments were conducted to illustrate their respective contribution in combined UV-chlorine treatment. It was found that the optimal removal percentage of 2,3,4-THBP under combined UV-chlorine treatment was 85.3% within 5 min and kept stable until 3 h at 3-equivalent (equiv.) of free available chlorine (FAC) and 1 mW/cm2 of irradiation intensity. Correspondingly, acute toxicity of reaction mixture at 3 h increased twice as high as that of 2,3,4-THBP itself. Four transformation products were tentatively identified, and their formation possibly involved the reactions of chlorine substitution, oxidation, hydroxylation, and hydrolysis. FAC initiated the preliminary transformation of 2,3,4-THBP, and the synergistic effects of UV and chlorine promoted the further transformation of intermediates from chlorination treatment. Most important was that, 2,3,4-THBP could form some toxic products in the real ambient water matrix under solar irradiation, and acute toxicity of reaction mixture was 1.84 times higher than that of 2,3,4-THBP. This study would provide a better understanding on the transformation characteristics of pollutants under combined UV-chlorine treatment, and provide a reference for optimizing disinfection treatment.
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Affiliation(s)
- Xinyi Zhang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Dongbin Wei
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Qi Yu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China; Environmental Development Center of the Ministry of Ecology and Environment (Sino-Japan Friendship Centre for Environmental Protection), Beijing, 100029, China
| | - Yuguo Du
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China
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290
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Goulart LA, Moratalla A, Lanza MR, Saez C, Rodrigo MA. Photocatalytic performance of Ti/MMO/ZnO at degradation of levofloxacin: Effect of pH and chloride anions. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2020.114894] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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291
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Luo H, Zhou X, Guo X, Fang Z, Chen Q, Zhou J. WS 2 as highly active co-catalyst for the regeneration of Fe(II) in the advanced oxidation processes. CHEMOSPHERE 2021; 262:128067. [PMID: 33182131 DOI: 10.1016/j.chemosphere.2020.128067] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 08/04/2020] [Accepted: 08/18/2020] [Indexed: 06/11/2023]
Abstract
The greatest constraint in the advanced oxidation processes involved Fe(II)/PMS was the low utilization of Fe(II) and PMS. In the present study, the co-catalytic effect of WS2 on the Fe(II)/PMS system for the degradation of organics was investigated. In the presence of WS2, Fe(III) was reduced to Fe(II) during the reaction and resulted in improved decomposition of PMS as well as the degradation of 4-chloriphenol (4-CP). The decomposition rate of PMS and degradation efficiency of 4-CP were 10% and 25% in the Fe(II)/PMS process, while the efficiencies respectively increased to 99% and 100% in the WS2 assisted Fe(II)/PMS system. The degradation of 4-CP was completed via the free radical pathway and SO4•- played a more important role than other active species. Low concentration of inorganic ions such as Cl- and HCO3- exhibited irrelevant effect while humic acid showed significant suppression on the WS2/Fe(II)/PMS system. Additionally, characterization and recycle results implied that WS2 maintained a good stability during the co-catalytic processes.
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Affiliation(s)
- Haopeng Luo
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China
| | - Xin Zhou
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China
| | - Xiaojie Guo
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China
| | - Zhiyong Fang
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China
| | - Quanyuan Chen
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China
| | - Juan Zhou
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
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292
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Hua Z, Li D, Wu Z, Wang D, Cui Y, Huang X, Fang J, An T. DBP formation and toxicity alteration during UV/chlorine treatment of wastewater and the effects of ammonia and bromide. WATER RESEARCH 2021; 188:116549. [PMID: 33152588 DOI: 10.1016/j.watres.2020.116549] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/16/2020] [Accepted: 10/21/2020] [Indexed: 05/03/2023]
Abstract
The UV/chlorine process is efficient for the abatement of micropollutants; yet, the formation of disinfection by-products (DBPs) and the toxicity can be altered during the treatment. This study investigated effluent organic matter characterization, DBP formation and toxicity alteration after the UV/chlorine treatment of wastewater; particularly, typical water matrix components in wastewater, namely, ammonia and bromide, were studied. The raw wastewater contained low levels of ammonia (3 µM) and bromide (0.5 µM). The UV/chlorine treatment efficiently eliminated 90 - 94% of fluorescent components. Compared with chlorination alone, a 20 min UV/chlorine treatment increased the formation of trihalomethanes (THMs), haloacetic acids (HAAs), chloral hydrate (CH), haloacetonitriles (HANs), trichloronitromethane (TCNM) and haloacetamides (HAcAms) by 90 - 508%. In post-chlorination after the UV/chlorine treatment, the formation of CH, HANs, TCNM and HAcAms increased by 77 - 274%, whereas the formation of both THMs and HAAs increased slightly by 11%. Meanwhile, the calculated cytotoxicity and genotoxicity of DBPs increased considerably after the UV/chlorine treatment and in post-chlorination, primarily due to the increased formation of HAAs and nitrogenous DBPs (N-DBPs). However, the acute toxicity of the wastewater to Vibrio fischeri and genotoxicity determined by the umu test decreased by 19% and 76%, respectively, after the 20 min UV/chlorine treatment. An additional 200 µM ammonia decreased the formation of all detected DBPs during the UV/chlorine treatment and 24 h post-chlorination, except that TCNM formation increased by 11% during post-chlorination. The acute toxicity of wastewater spiked with 200 µM ammonia was 32% lower than that of raw wastewater after the UV/chlorine treatment, but the genotoxicity was 58% higher. The addition of 1 mg/L bromide to the UV/chlorine process dramatically increased the formation of brominated DBPs and the overall calculated cytotoxicity and genotoxicity of DBPs. However, the acute toxicity and genotoxicity of the wastewater decreased by 7% and 100%, respectively, when bromide was added to the UV/chlorine treatment. This study illuminated that UV/chlorine treatment can decrease acute and geno- toxicities of wastewater efficiently.
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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
| | - Dan Li
- Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Zihao Wu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Ding Wang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China; Independent researcher, 25 Tuscany Springs Terr NW, Calgary, AB T3L 2V2, Canada
| | - Yonglin Cui
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
| | - Xiongfei 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.
| | - Taicheng An
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
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293
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Transformation of Contaminants of Emerging Concern (CECs) during UV-Catalyzed Processes Assisted by Chlorine. Catalysts 2020. [DOI: 10.3390/catal10121432] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Every compound that potentially can be harmful to the environment is called a Contaminant of Emerging Concern (CEC). Compounds classified as CECs may undergo different transformations, especially in the water environment. The intermediates formed in this way are considered to be toxic against living organisms even in trace concentrations. We attempted to identify the intermediates formed during single chlorination and UV-catalyzed processes supported by the action of chlorine and hydrogen peroxide or ozone of selected contaminants of emerging concern. The analysis of post-processing water samples containing benzocaine indicated the formation of seven compound intermediates, while ibuprofen, acridine and β-estradiol samples contained 5, 5, and 3 compound decomposition by-products, respectively. The number and also the concentration of the intermediates decreased with the time of UV irradiation. The toxicity assessment indicated that the UV-catalyzed processes lead to decreased toxicity nature of post-processed water solutions.
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294
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Xiang Y, Gonsior M, Schmitt-Kopplin P, Shang C. Influence of the UV/H 2O 2 Advanced Oxidation Process on Dissolved Organic Matter and the Connection between Elemental Composition and Disinfection Byproduct Formation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14964-14973. [PMID: 33179505 DOI: 10.1021/acs.est.0c03220] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The UV/H2O2 process is a promising advanced oxidation process (AOP) for micropollutant abatement in drinking water treatment and water reuse plants. However, during micropollutant degradation by the AOP, dissolved organic matter (DOM) and the disinfection byproduct (DBP) formation potential may also be altered. This study investigated the influence of the UV/H2O2 AOP on the elemental composition and DBP formation potential of two DOM isolates by using ultrahigh-resolution mass spectrometry (UHRMS). After the AOP, 629 new chemical formulas with an increased degree of oxidation and decreased aromaticity were obtained. Such alterations led to the formation of 226 unknown DBPs with decreased aromaticity indices (AImod) in the subsequent 3-day chlorination. Links between the unknown DBPs and the corresponding precursors in DOM were visualized by network computational analysis. The analysis gave three zones in the van Krevelen diagram based on the possibility of the C7-22HnOm formulas located in each zone to link to the corresponding DBPs. A further investigation with two model compounds reconfirmed the hydroxylation and ring cleavage of DOM by HO· attack during the AOP and the influence on DBP formation. These results obtained from UHRMS build the connection between the elemental composition of DOM and the formation potential of DBPs.
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Affiliation(s)
- Yingying Xiang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 000, Hong Kong SAR
| | - Michael Gonsior
- Chesapeake Biological Laboratory, University of Maryland Center for Environmental Science, Solomons, Maryland 20688, United States
| | - Philippe Schmitt-Kopplin
- Helmholtz Zentrum Muenchen, Research Unit Analytical BioGeoChemistry, Neuherberg 85764, Germany
- Technische Universität München, Chair of Analytical Food Chemistry, Freising-Weihenstephan 80333, Germany
| | - Chii Shang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon 000, Hong Kong SAR
- 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 000, Hong Kong SAR
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295
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Yang B, Peng T, Cai WW, Ying GG. Transformation of diazepam in water during UV/chlorine and simulated sunlight/chlorine advanced oxidation processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 746:141332. [PMID: 32758990 DOI: 10.1016/j.scitotenv.2020.141332] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 06/20/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
Psychoactive drug diazepam is one of benzodiazepines widely used in human medicine. It has been found to be relatively resistant to chlorination and photolysis. Here we investigated the transformation mechanism of diazepam in aqueous solution through UV/chlorine and simulated sunlight/chlorine treatments. The results showed that the UV/chlorine and sunlight/chlorine processes significantly increased the degradation of diazepam in water. These observed degradations can be elucidated by in-situ generation of reactive species including hydroxyl radical (HO), reactive chlorine species (RCS) and ozone (O3) during photolysis of chlorine. In the UV/chlorine treatment, the degradation efficiency of diazepam for HO, chlorine, UV and RCS reaction at 90 min was calculated to be 62.1%, 3.8%, 11.9% and 12.3%, respectively. In the simulated sunlight/chlorine treatment, the calculated degradation of 53.1%, 8.1% and 11.2% was attributed to HO, chlorine and RCS reaction, with negligible loss by O3 reaction and sunlight irradiation. In the UV/chlorine and sunlight/chlorine treatments, a total of 70 transformation products was detected using a high-resolution TripleTOF mass system. Six transformation pathways have been tentatively proposed for the diazepam, which includes hydroxylation, chlorination, hydrolyzation, N-demethylation, loss of phenyl group, benzodiazepine ring rearrangement and contraction. Most of the obtained transformation products were less toxic to aquatic organisms including fish, daphnia and green algae than diazepam itself according to the toxicity prediction tool, and did not cause significant changes in toxicity to luminescent bacteria.
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Affiliation(s)
- Bin Yang
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China; School of Environment, South China Normal University, Guangzhou 510006, China.
| | - Tao Peng
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Wen-Wen Cai
- State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Guang-Guo Ying
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China; School of Environment, South China Normal University, Guangzhou 510006, China
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296
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Wang J, Wan Y, Ding J, Wang Z, Ma J, Xie P, Wiesner MR. Thermal Activation of Peracetic Acid in Aquatic Solution: The Mechanism and Application to Degrade Sulfamethoxazole. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14635-14645. [PMID: 33108174 DOI: 10.1021/acs.est.0c02061] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Chemical oxidation using peracetic acid (PAA) can be enhanced by activation with the formation of reactive species such as organic radicals (R-O•) and HO•. Thermal activation is an alternative way for PAA activation, which was first applied to degrade micropollutants in this study. PAA is easily decomposed by heat via both radical and nonradical pathways. Our experimental results suggest that a series of reactive species including R-O•, HO•, and 1O2 can be produced through the thermal decomposition of PAA. Sulfamethoxazole (SMX), a typical sulfa drug, can be effectively removed by the thermoactivated PAA process under conditions of neutral pH. R-O• including CH3C(O)O• and CH3C(O)OO• has been shown to play a primary role in the degradation of SMX followed by direct PAA oxidation in the thermoactivated PAA process. Both higher temperature (60 °C) and higher PAA dose benefit SMX degradation, while coexisting H2O2 inhibits SMX degradation in the thermoactivated PAA process. With a variation of solution pH, conditions near a neutral value show the best performance of this process in SMX degradation. Based on the identified intermediates, transformation of SMX was proposed to undergo oxidation of the amine group and oxidative coupling reactions. This study definitively illustrates the PAA decomposition pathways at high temperature in aquatic solution and addresses the possibility of the thermoactivated PAA process for contaminant destruction, demonstrating this process to be a feasible advanced oxidation process.
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Affiliation(s)
- Jingwen Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Ying Wan
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jiaqi Ding
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Zongping Wang
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Pengchao Xie
- School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
- Center for the Environmental Implications of Nanotechnology (CEINT), Durham, North Carolina 27708-0287, United States
| | - Mark R Wiesner
- Center for the Environmental Implications of Nanotechnology (CEINT), Durham, North Carolina 27708-0287, United States
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297
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Lai X, Ning XA, Chen J, Li Y, Zhang Y, Yuan Y. Comparison of the Fe 2+/H 2O 2 and Fe 2+/PMS systems in simulated sludge: Removal of PAHs, migration of elements and formation of chlorination by-products. JOURNAL OF HAZARDOUS MATERIALS 2020; 398:122826. [PMID: 32506047 DOI: 10.1016/j.jhazmat.2020.122826] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 04/23/2020] [Accepted: 04/23/2020] [Indexed: 06/11/2023]
Abstract
In this study, polycyclic aromatic hydrocarbons (PAHs) at practical concentrations in the simulated sludge treated by the Fe2+/H2O2 and Fe2+/peroxymonosulfate (PMS) systems were evaluated in terms of the PAHs (phenanthrene, anthracene, fluoranthene) removal, element migration, Cl- effect, and chlorination by-product formation. The results indicated that according to the removal rate of PAHs, the optimal dosage of the Fe2+/PMS system (∑PAHs removal rate was 64.66 ± 2.82 %) was 1/30 of that for the Fe2+/H2O2 system (∑PAHs removal rate was 78.63 ± 0.38 %). The elemental contents in the simulated sludge were mainly affected by the extent of advanced oxidation and the amount of generated iron flocs. By studying the PAHs removal, free chlorine formation, total organochlorine content, and PAHs products in Fe2+/H2O2/Cl- and Fe2+/PMS/Cl- systems, it was found that chlorine radicals (·Cl) had high reactivity with phenanthrene and fluoranthene, whereas dichloride anion radicals (Cl2·-) exhibited the opposite behavior. Furthermore, PAHs were oxidized by ·Cl and hydroxyl radical in the Fe2+/H2O2/Cl- system, whereas PAHs and their products were chlorinated by free chlorine and ·Cl in the Fe2+/PMS/Cl- system to six chlorinated by-products such as Cl-PAHs (9-Cl-phenanthrene, 2-Cl-anthracene, 9,10-Cl2-anthracene, 3-Cl-fluoranthene). These results provide some useful suggestions for the safe advanced oxidation process treatment of textile dyeing sludge.
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Affiliation(s)
- Xiaojun Lai
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Xun-An Ning
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China.
| | - Jiayi Chen
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Yang Li
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Yaping Zhang
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
| | - Yiqian Yuan
- Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, School of Environmental Science and Engineering, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China
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298
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Qin W, Lin Z, Dong H, Yuan X, Qiang Z, Liu S, Xia D. Kinetic and mechanistic insights into the abatement of clofibric acid by integrated UV/ozone/peroxydisulfate process: A modeling and theoretical study. WATER RESEARCH 2020; 186:116336. [PMID: 32889366 DOI: 10.1016/j.watres.2020.116336] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 08/08/2020] [Accepted: 08/23/2020] [Indexed: 06/11/2023]
Abstract
The feasibility of integrated UV/ozone (O3)/peroxydisulfate (PDS) process for abatement of clofibric acid (CA) was systematically explored in this study with focus on the kinetic simulation and oxidation mechanisms. The results indicated the UV/O3/PDS process was of prominent treatment capability with pseudo-first-order rate constant of CA degradation increased by 65.9% and 86.0% compared to UV/O3 and UV/PDS processes, respectively. A chemical kinetic model was developed and successfully employed to predict CA elimination as well as the specific contributions of UV, hydroxyl radical (•OH) and sulfate radical (SO4•-) under different PDS dosage, pH, natural organic matters, bicarbonate and chloride conditions in UV/O3/PDS process. According to quantum chemical calculation, radical addition on ortho site of isopropoxy substituent and single electron transfer were corroborated to be the dominant reaction channels for the oxidation of CA by •OH and SO4•-, respectively. Additionally, the reactive sites and transformation pathways of CA were proposed via Fukui function calculation and UPLC-Q-TOF-MS analysis. Moreover, the performance of UV/O3/PDS process was further evaluated with regard to the energy demand and bromate formation. This study first proposed a kinetic model in UV/O3/PDS process and elucidated the regioselectivity and products distribution of CA during oxidative treatment.
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Affiliation(s)
- Wenlei Qin
- School of Environmental Engineering, Wuhan Textile University, No.1 Sunshine Avenue, Wuhan 430200, China; Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing 100085, China
| | - Zhuang Lin
- School of Environmental Engineering, Wuhan Textile University, No.1 Sunshine Avenue, Wuhan 430200, China
| | - Huiyu Dong
- Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing 100085, China
| | - Xiangjuan Yuan
- School of Environmental Engineering, Wuhan Textile University, No.1 Sunshine Avenue, Wuhan 430200, China; Engineering Research Center for Clean Production of Textile Dyeing and Printing, Ministry of Education, No.1 Sunshine Avenue, Wuhan 430200, China.
| | - Zhimin Qiang
- Research Center for Eco-Environmental Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 18 Shuang-qing Road, Beijing 100085, China
| | - Shaogang Liu
- School of Chemistry and Chemical Engineering, Guangxi University for Nationalities, 158 Da-xue Road, Nanning 530008, China
| | - Dongsheng Xia
- School of Environmental Engineering, Wuhan Textile University, No.1 Sunshine Avenue, Wuhan 430200, China; Engineering Research Center for Clean Production of Textile Dyeing and Printing, Ministry of Education, No.1 Sunshine Avenue, Wuhan 430200, China.
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299
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Cheng S, Wu J, Zuo YT, Han YZ, Ji WX, Li Y, Huo ZL, Li AM, Li WT. Developing a restricted chlorine-dosing strategy for UV/chlorine and post-chlorination under different pH and UV irradiation wavelength conditions. CHEMOSPHERE 2020; 258:127393. [PMID: 32947669 DOI: 10.1016/j.chemosphere.2020.127393] [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: 03/18/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
UV/chlorine and chlorination processes have drawn great interests of water treatment utilities for oxidation and disinfection purposes. This work proposed a restricted chlorine-dosing strategy for UV/chlorine and post-chlorination under different pH and UV irradiation conditions by comprehensively assessing the oxidation of natural organic matter (NOM), formation of 9 haloacetic acids (HAA9) and bromate, and alteration of toxicity. During UV/chlorine with restricted chlorine doses, the oxidation of NOM chromophores (i.e., ΔUVA254) showed an apparent dependence on cumulative exposures of free available chlorine (CTFAC); Meanwhile, HAA9 formation was determined by CTFAC values and could be linearly correlated with ΔUVA254 irrespective of pH and UV irradiation wavelength. Irradiated by 254 nm LP-Hg lamp, the faster chlorine photolysis produced relatively higher steady-state concentrations of Cl• and HO• species but resulted in lower CTFAC. Reducing CTFAC values by operation parameters (pH, UV wavelength and irradiation fluence) could mitigate HAA9 formation during UV/chlorine at a specific chlorine dose. Additionally, high bromide concentration and acidic pH promoted more bromo-HAAs formation, and the presence of NOM significantly suppressed bromate formation. Analogous to ozonation, the UV/chlorine pre-oxidation could reduce the HAA9 formation potentials during post-chlorination at mildly alkaline pH. The photobacterium bioassay further demonstrated that although the UV/chlorine treatment might have increased the acute toxicity, the post-chlorination treatment could polish the acute toxicity to the level of chlorination alone. These results suggest that with the restricted chlorine-dosing strategy, the trade-off between oxidation/disinfection efficiency and DBPs formation can be controlled by monitoring CTFAC and ΔUVA254 values during UV/chlorine treatment.
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Affiliation(s)
- Shi Cheng
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Ji Wu
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Yan-Ting Zuo
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Yu-Ze Han
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Wen-Xiang Ji
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Yan Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Zong-Li Huo
- Jiangsu Province Center for Disease Control and Prevention, Nanjing, 210023, China
| | - Ai-Min Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Wen-Tao Li
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China.
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300
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Kang J, Zhou L, Duan X, Sun H, Wang S. Catalytic degradation of antibiotics by metal-free catalysis over nitrogen-doped graphene. Catal Today 2020. [DOI: 10.1016/j.cattod.2018.12.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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