Journal of Environmental Sciences
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2020
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IF 4.302
Biao Yang,Hua Fang,Bingqi Chen,Shun Yang,Zhichao Ye,Jianghua Yu
Chlorine dioxide (ClO 2 ) disinfection usually does not produce halogenated disinfection by-products, but the formation of the inorganic by-product chlorite (ClO 2 – ) is a serious consideration. In this study, the ClO 2 – formation rule in the ClO 2 disinfection of drinking water was investigated in the presence of three representative reductive inorganics and four natural organic matters (NOMs), respectively. Fe 2+ and S 2– mainly reduced ClO 2 to ClO 2 – at low concentrations. When ClO 2 was consumed, the ClO 2 – would be further reduced by Fe 2+ and S 2– , leading to the decrease of ClO 2 – . The reaction efficiency of Mn 2+ with ClO 2 was lower than that of Fe 2+ and S 2– . It might be the case that MnO 2 generated by the reaction between Mn 2+ and ClO 2 had adsorption and catalytic oxidation on Mn 2+ . However, Mn 2+ would not reduce ClO 2 – . Among the four NOMs, humic acid and fulvic acid reacted with ClO 2 actively, followed by bovine serum albumin, while sodium alginate had almost no reaction with ClO 2 . The maximum ClO 2 – yields of reductive inorganics (70%) was higher than that of NOM (around 60%). The lower the concentration of reductive substances, the more ClO 2 – could be produced by per unit concentration of reductive substances. The results of the actual water samples showed that both reductive inorganics and NOM played an important role in the formation of ClO 2 – in disinfection.
研究领域:
环境科学
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水处理
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2021
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IF 7.963
Mengge Fan,Xin Yang,Qingqing Kong,Yu Lei,Xinran Zhang,Ehsan Aghdam,Ran Yin,Chii Shang
This study systematically revealed the feasibility of the sequential ClO 2 -UV/chlorine process for micropollutant removal and disinfection byproduct (DBP) control. The results demonstrated that the sequential ClO 2 -UV/chlorine process was effective for the removal of 12 micropollutants. ClO 2 pre-treatment reduced the formation of disinfect byproducts (DBPs) in the UV/chlorine process. Compared to the UV/chlorine process, ClO 2 pre-treatment (1.0 mg L −1 ) decreased the formation of the 6 DBPs by 25.1–72.2%; and decreased the formation potential of the 6 DBPs by 13.9–51.8%. Moreover, ClO 2 pre-treatment reduced the concentration of total organic chlorine by 19.8%. ClO 2 pre-treatment affected the UV/chlorine process in different ways. Firstly, ClO 2 pre-treatment generated chlorite, which dominantly served as a scavenger of chlorine radical (Cl ) and hydroxyl radical (HO ). Secondly, ClO 2 pre-treatment decreased the reactivity of natural organic matter (NOM) towards radicals. Finally, ClO 2 pre-treatment altered the properties of NOM, in terms of reducing the electron-donating capacity and aromaticity of NOM (SUVA 254 ), and slightly reducing the average molecular weight of NOM. Overall, ClO 2 pre-treatment effectively controlled the formation of DBPs in the UV/chlorine process. This study confirmed the sequential ClO 2 -UV/chlorine process was an alternative strategy to balancing the micropollutant removal and DBP control.
研究领域:
环境科学
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水处理
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
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2023
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IF 8.8
Jiafu Li,Jingsi Chen,Zhiyong Hu,Xinyu Li,Mei Li,Yuan Wang,Zengli Zhang,Xiaojun Liang
Trichloroisocyanuric acid (TCCA) is a popular disinfectant for swimming pools in China. However, the occurrence and importance of regulated disinfection byproducts (DBPs) in TCCA-disinfected swimming pools are less understood. This study analyzed 12 regulated DBPs (4 trihalomethanes (THMs), 5 haloacetic acid (HAAs), bromate , chlorate, and chlorite) in 85 swimming pool water samples and 17 input tap water samples from one swimming pool for 17 days continuously. Considering water temperature, pH, free chlorine, total chlorine, and urea, most of swimming pool water samples were within the water quality limits for China. Total concentrations of THMs, HAAs, and inorganic DBPs of 20.4–42.2, 82.0–229, and 100–729 μg/L in the swimming pool, and 16.6–28.3, 8.2–12.8, and 64.4–95.6 μg/L in the tap water, indicating inorganic DBPs are the dominant swimming pool and drinking water pollutants. Cancer risk values of regulated DBPs in swimming pools and input tap water are 2.7E-05 and 8.1E-05, respectively, and exceed the US EPA's threshold (1.0E-06). The non-cancer risk is below the US EPA's threshold. Following TCCA disinfection, the concentration and calculated cytotoxicity of regulated DBPs had a 3.6-fold and 1.9-fold increase, respectively. Inorganic DBPs contribute to the calculated concentration and cancer risks of DBPs in swimming pools and tap water at sufficient concentrations warranting regulation. This study provides data on 12 regulated DBPs in TCCA-disinfected indoor swimming pools, highlighting the importance of inorganic DBPs from evidences of concentration, cytotoxicity, and cancer risk for the first time.
研究领域:
环境科学
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公共卫生
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水质
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毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）