CHEMOSPHERE
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2022
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IF 8.943
Zhangbin Pan,Zhenqi Du,Junqi Jia,Aiguo Lin,Yongqiang Wang,Wuchang Song,Shaohua Sun,Hongbo Wang,Ruibao Jia,Lian Hou
2,6-dichloro-1,4-benzoquinone (DCBQ), a typical representative of Halobenzoquinones, is an emerging aromatic disinfection by-product (DBP) with high toxicity and carcinogenicity , generated commonly through the chlorination in the drinking water disinfection process while there is still a lack of research on its removal. In this study, the effects of ultraviolet-based advanced oxidation processes (UV-AOPs) on the degradation of DCBQ were evaluated. The results showed that UV-AOPs are effective in degrading DCBQ. The removal of DCBQ by UV/H 2 O 2 /O 3 was more significant than by UV/H 2 O 2 or UV/O 3, achieving a 96.7% removal rate at both the O 3 and H 2 O 2 doses of 1 mg/L. The results also indicated the alkaline and weakly acidic environments could facilitate the degradation of DCBQ, inorganic anions could inhibit DCBQ degradation and the degree of inhibition increased as the matrix concentration increased. The degradation of DCBQ was inhibited more by the CO 3 2− than the other matrix components, such as Cl − and NO 3 − . It was shown by the density functional theory simulations and the ultrahigh-performance liquid chromatography (UPLC) - Orbitrap mass spectra that the electrons in DCBQ are mainly on the chlorine atom connected to the carboatomic ring and that OH• can attack the chlorine atom to cause de-chlorination. The DCBQ degradation pathway may involve the oxidation of DCBQ to 3-hydroxy-2,6-DCBQ (HO–DCBQ) and 3,5-dichloro-1,2,4-pyrogallol, the further degradation of intermediate products by OH• to dechlorinated forms of HO–DCBQ and DCBQ.
研究领域:
环境科学
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水处理工程
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化学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
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2021
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IF 7.086
Hongyan Zhai,Jun Zhao,Rumeng Wang,Yuwei Yan,Shanshan Yu,Yingxin Zhao
As a typical aromatic disinfection byproduct (DBP), 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ) attracts much concern due to the potential toxicity. To further evaluate the role of 2,6-DCBQ as an intermediate DBP in water with or without chlorine, their decomposition characteristics and transformation potential to the regulated DBPs (i.e., trihalomethanes (THMs) and haloacetic acids (HAAs)) were investigated under different chlorine doses, pH values, temperatures, contact times, and bromide levels. The decomposition of 2,6-DCBQ under different conditions all fit apparent first-order kinetics. The hydrolysis rate constants of 2,6-DCBQ significantly increased with pH. The half-live values of 2,6-DCBQ were 108.3–568.7 h at pH 6.0–6.5, and 1.8–31.1 h at pH 7.0–8.5. During the hydrolysis of 2,6-DCBQ, there was no THMs and HAAs generated. During chlorination, 2,6-DCBQ decayed rapidly accompanied by the fast formation of trichloromethane (TCM) and the gradual generation of dichloroacetic acid and trichloroacetic acid. The molar conversion rates of 2,6-DCBQ-to-THMs (i.e., TCM) and 2,6-DCBQ-to-HAAs were 2.9–10.0% and 0.1–2.2% under different conditions. The presence of bromide increased the conversion rates of 2,6-DCBQ-to-THMs and caused the generation of brominated THMs and HAAs. According to the decomposition characteristics of 2,6-DCBQ and the formation trends of THMs and HAAs under different conditions, multiple formation pathways from 2,6-DCBQ to THMs and HAAs were proposed.
研究领域:
环境科学
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水处理工程
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化学动力学
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
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2021
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IF 9.028
Shuo Xu,Shaoyang Hu,Lizhong Zhu,Wei Wang
Haloquinone chloroimides (HQCs) are suspected to be highly toxic contaminants, and their production during drinking water disinfection is predicted. However, HQC disinfection byproducts (DBPs) have not been reported in drinking water to date because of analytical limitations. In this study, we developed an analytical method to detect five HQCs, including 2,6-dichloroquinone-4-chloroimide (2,6-DCQC), 2,6-dibromoquinone-4-chloroimide (2,6-DBQC), 2-chloroquinone-4-chloroimide (2-CQC), 3-chloroquinone-4-chloroimide (3-CQC), and 2,6-dichloroquinone-3-methyl-chloroimide (2,6-DCMQC). This method combined a derivatization reaction of HQCs with phenol in alkaline solutions to produce halogenated indophenols, a solid-phase extraction pretreatment using hydrophilic–lipophilic balanced (HLB) cartridges, and a multiple reaction monitoring (MRM) method for quantification. The method was demonstrated to be sensitive and accurate with recoveries of 71–85% and limits of detection of 0.1–0.2 ng/L for the five tested HQCs. Using this method, five tested HQCs were identified in drinking water samples from nine water treatment plants and water distribution systems as new DBPs at concentrations of up to 23.1 ng/L. The cytotoxicity of the five tested HQCs in HepG2 cells was higher than or comparable to that of 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ), an emerging DBP that was hundreds to thousands of times more toxic than regulated DBPs. This study presents the first analytical method for HQC DBPs in drinking water and the first set of occurrence and cytotoxicity data of HQC DBPs.
研究领域:
环境科学
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化学工程
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分析化学
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毒理学
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水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Xu-Hui Sun,Jiang Wu,Ying-Chun Yu,Zheng-Chao Shen,Muhammad Mujahid Ali,Zhen-Xia Du
The disinfection of drinking water is an important treatment process for protecting consumers from potential waterborne infectious and parasitic pathogens. However, the disinfection process may introduce disinfection by-products (DBPs), which are harmful to human health. It is necessary to control the contents of DBPs and their precursors. In this study, we synthesized Fe 3 O 4 @SiO 2 @PDA@NH 2 -MIL-53(Fe) magnetic composites via layer-by-layer self-assembly method. This green and eco-friendly materials were thoroughly characterized and used to adsorb the highly toxic DBPs, 2,6-dichloro-1,4-benzoquinone (2,6-DCBQ) and its precursors, bisphenol A and phenol . The maximum adsorption quantity of Fe 3 O 4 @SiO 2 @PDA@NH 2 -MIL-53(Fe) was up to 109.3 mg g -1 for 2,6-DCBQ, 82.4 mg g -1 for bisphenol A, and 64.8 mg g -1 for phenol. The saturation magnetization value of Fe 3 O 4 @SiO 2 @PDA@NH 2 -MIL-53(Fe) was 39 emu g -1 , which could be fast magnetic separated. In addition, the adsorption process was fitted into the pseudo-first-order adsorption model and Freundlich equation, in which π-π interaction, hydrogen bond and pore-filling were the main adsorption mechanisms. After 5 cycles, the adsorption rate of the as-synthesized magnetic composites is still more than 80%. Due to its fast and strong adsorption capability, excellent stability, and easy separation ability from water, Fe 3 O 4 @SiO 2 @PDA@NH 2 -MIL-53(Fe) magnetic composites have the potential to be a promising adsorption material for removing the disinfection by-products in future.
研究领域:
环境科学
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材料科学
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水处理
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）