Role of reactive oxygen species in the dechlorination of trichloroethene and 1.1.1-trichloroethane in aqueous phase in UV/TiO2 systems
Role of reactive oxygen species in the dechlorination of trichloroethene and 1.1.1-trichloroethane in aqueous phase in UV/TiO2 systems
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活性氧在 UV/TiO2 系统水相中三氯乙烯和 1.1.1-三氯乙烷脱氯中的作用
DOI：
10.1016/j.ces.2014.11.034
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发表时间：
2015-02
影响因子：
4.7
通讯作者：
Bozhong Mu
中科院分区：
文献类型：
--
作者：
L;ry Biyoghe Bi Ndong;Xiaogang Gu;Shuguang Lu;Murielle Primaelle Ibondou;Zhaofu Qiu;Qian Sui;Serge Maurice Mbadinga;Bozhong Mu
研究了紫外光（UV）和UV/TiO2对水溶液中三氯乙烯（TCE）和1.1.1-三氯乙烷（TCA）的降解和脱氯性能。pH值的影响和目标污染物的降解过程中产生的活性氧物种的作用进行了评价。采用钛酸四丁酯和氢氟酸的简单水热溶液合成了TiO2，并通过X射线衍射（XRD）、Brunauer − Emmett − Teller（BET）分析、透射电子显微镜（TEM）和X射线光电子能谱（XPS）进行了表征。结果表明，TiO2以Ti-F键的形式存在于光催化剂表面，形成了规则的片状结构，呈长方形。TCE和TCA在光照60 min和90 min时完全降解（100%），TCE的降解符合准一级动力学模型，而TCA的降解呈现先缓慢后快速的变化规律。pH对TCE降解的抑制作用可以忽略不计，因为在所有测试的pH溶液中都发生了完全降解。相反，pH影响TCA的降解。使用硝基苯（NB）和四氯甲烷（CT）进行的探针化合物测试发现了UV/TiO 2系统中羟基自由基（·OH）和超氧自由基阴离子（O2·-）的产生。自由基淬灭研究表明，所有研究的活性氧化物种的TCE和TCA降解。O2·−和·OH是主要的自由基，对降解过程的贡献大于3O2自由基。本研究结果可为进一步开展UV/TiO2修复含氯溶剂地下水的研究提供参考。
The performance of trichloroethene (TCE) and 1.1.1-trichloroethane (TCA) degradation and dechlorination in aqueous solution using UV and UV/TiO2was investigated. The effects of pH and the roles of the reactive oxygen species generated during the degradation of the target contaminant were evaluated. The TiO2was synthesized using a simple hydrothermal solution containing tetrabutyl-titanate and hydrofluoric acid and was characterized by X-ray diffraction (XRD), Brunauer−Emmett−Teller (BET) analysis, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The results showed that the TiO2, which was in the form of anatase, consisted of well-defined sheet-shaped structures with a rectangular outline≡Ti-F bonds that were formed on the surfaces of photocatalysts. TCE and TCA were completely degraded (100%) in 60 and 90 min of illumination, and the degradation of TCE followed the pseudo-first order kinetic model, while the degradation of TCA showed a slow degradation stage initially followed by a fast stage later. The inhibitive effects of pH on TCE degradation were negligible because complete degradation occurred in all the tested pH solutions. Instead, the pH affected the degradation of TCA. Probe compound tests using nitrobenzene (NB) and tetrachloromethane (CT) identified the generation of hydroxyl radicals (•OH) and the superoxide radical anion (O2•−) in the UV/TiO2system. Free radical quenching studies demonstrated that all of the studied reactive oxidative species contributed to the TCE and TCA degradation. However, O2•−and•OH were main detected radicals and contributed more to the degradation process than the3O2radical. It is believed that the results from this study can be used to support further UV/TiO2studies for remediating groundwater contaminated with chlorinated solvents.
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影响因子：
11.4
作者：
T. Vogel;P. McCarty
通讯作者：
T. Vogel;P. McCarty
影响因子：
3.2
作者：
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通讯作者：
T. Whang;M. Hsieh;T. Shi;C. Kuei
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11.4
作者：
Ryu, J;Choi, W
通讯作者：
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影响因子：
8.8
作者：
Liang, Chenju;Wang, Zih-Sin;Bruell, Clifford J.
通讯作者：
Bruell, Clifford J.
影响因子：
13.6
作者：
J. Joo;C. Ahn;D. Jang;Y. Yoon;J. K. Kim;L. Campos;Hosang Ahn
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