Quantitative Structure鈥揂ctivity Relationship (QSAR) for the Oxidation of Trace Organic Contaminants by Sulfate Radical
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- 作者：Ruiyang Xiao ; Tiantian Ye ; Zongsu Wei ; Shuang Luo ; Zhihui Yang ; Richard Spinney
- 刊名：Environmental Science & Technology
- 出版年：2015
- 出版时间：November 17, 2015
- 年：2015
- 卷：49
- 期：22
- 页码：13394-13402
- 全文大小：428K
- ISSN：1520-5851
文摘
The sulfate radical anion (SO4鈥⑩€?/sup>) based oxidation of trace organic contaminants (TrOCs) has recently received great attention due to its high reactivity and low selectivity. In this study, a meta-analysis was conducted to better understand the role of functional groups on the reactivity between SO4鈥⑩€?/sup> and TrOCs. The results indicate that compounds in which electron transfer and addition channels dominate tend to exhibit a faster second-order rate constants (kSO4鈥⑩€?/sup>) than that of H鈥揳tom abstraction, corroborating the SO4鈥⑩€?/sup> reactivity and mechanisms observed in the individual studies. Then, a quantitative structure activity relationship (QSAR) model was developed using a sequential approach with constitutional, geometrical, electrostatic, and quantum chemical descriptors. Two descriptors, ELUMO and EHOMO energy gap (ELUMO鈥?i>EHOMO) and the ratio of oxygen atoms to carbon atoms (#O:C), were found to mechanistically and statistically affect kSO4鈥⑩€?/sup> to a great extent with the standardized QSAR model: ln kSO4鈥⑩€?/sup> = 26.8鈥?.97 脳 #O:C 鈥?0.746 脳 (ELUMO鈥?i>EHOMO). In addition, the correlation analysis indicates that there is no dominant reaction channel for SO4鈥⑩€?/sup> reactions with various structurally diverse compounds. Our QSAR model provides a robust predictive tool for estimating emerging micropollutants removal using SO4鈥⑩€?/sup> during wastewater treatment processes.