个人信息Personal Information
副教授
博士生导师
硕士生导师
任职 : 环境生态与工程研究生导师纵向党支部书记
性别:男
毕业院校:中科院南京土壤所
学位:博士
所在单位:环境学院
学科:环境科学
办公地点:环境楼B409
联系方式:办公电话:84707189 手机:13610848936
电子邮箱:xlqiao@dlut.edu.cn
Faster photodegradation rate and higher dioxin yield of triclosan induced by cationic surfactant CTAB
点击次数:
论文类型:期刊论文
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.
上一条:Development of in silico models for predicting LSER molecular parameters and for acute toxicity prediction to fathead minnow (Pimephales promelas)
下一条:Development and validation of theoretical linear solvation energy relationship models for toxicity prediction to fathead minnow (pimephales promelas)