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    谢晴

    • 高级工程师    
    • 主要任职:无
    • 性别:女
    • 毕业院校:大连理工大学
    • 学位:博士
    • 在职信息:在职
    • 所在单位:环境学院
    • 学科:环境工程
    • 办公地点:环境楼A315
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    Faster photodegradation rate and higher dioxin yield of triclosan induced by cationic surfactant CTAB

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    论文类型:期刊论文

    第一作者:Qiao, Xianliang

    通讯作者:Qiao, XL (reprint author), Dalian Univ Technol, Sch Environm Sci & Technol, Key Lab Ind Ecol & Environm Engn MOE, Linggong Rd 2, Dalian 116024, Peoples R China.

    合写作者:Zheng, Xiaodong,Xie, Qing,Yang, Xianhai,Xiao, Jie,Xue, Weifeng,Chen, Jingwen

    发表时间:2014-06-30

    发表刊物:JOURNAL OF HAZARDOUS MATERIALS

    收录刊物:SCIE、EI、PubMed、Scopus

    卷号:275

    页面范围:210-214

    ISSN号:0304-3894

    关键字:Triclosan; Surfactants; CTAB; pKa; Anionic speciation, Dioxin yield

    摘要:Triclosan has received extensive attention as it has been frequently detected in the aquatic environment. Photolysis was found to be a major pathway governing the fate of triclosan in the aquatic environment. However, the effects of surfactants that usually coexist with triclosan, on the photodegradation of triclosan, are largely unknown. In this study, the effects of selected surfactants on the photodegradation of triclosan were investigated experimentally. The results show that anionic sodium dodecyl benzene sulfonate, sodium dodecyl sulfate and neutral polyoxyethylene (20) sorbitan monooleate inhibit the photolysis of triclosan, whereas cationic cetyltrimethylammonium bromide (CTAB) significantly accelerates the photodegradation rate of triclosan. The interactions between the hydrophilic group of CAB and anionic triclosan lead to the apparent decrease of pK(a) of triclosan from 8.4 to 6.1, which increase the fraction of anionic triclosan from 4% to 89% in neutral solution. A red shift in the UV-VIS absorption spectrum is exhibited, thus leading to the increased photodegradation rate of triclosan. The accelerations caused by CTAB were observed under xenon lamp and Hg lamp irradiances, as well as under natural sunlight. Effect of CTAB demonstrated pH dependence with significantly enhancement under pH 5 similar to 9 and inhibition at pH=3. The presence of CTAB also increased the yield of 2,8-dichlorodibenzo-p-dioxin from the photolysis of triclosan about 7 times at pH=7. (C) 2014 Elsevier B.V. All rights reserved.