Mechanistic insight into degradation of endocrine disrupting chemical by hydroxyl radical: An experimental and theoretical approach

Ruiyang Xiao; Lingwei Gao; Zongsu Wei; Richard Spinney; Shuang Luo; Donghong Wang; Dionysios D Dionysiou; Chong-Jian Tang; Weichun Yang

doi:10.1016/j.envpol.2017.09.006

Mechanistic insight into degradation of endocrine disrupting chemical by hydroxyl radical: An experimental and theoretical approach

Environ Pollut. 2017 Dec;231(Pt 2):1446-1452. doi: 10.1016/j.envpol.2017.09.006. Epub 2017 Sep 13.

Authors

Ruiyang Xiao¹, Lingwei Gao¹, Zongsu Wei², Richard Spinney³, Shuang Luo¹, Donghong Wang⁴, Dionysios D Dionysiou⁵, Chong-Jian Tang⁶, Weichun Yang⁷

Affiliations

¹ Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China.
² Grand Water Research Institute - Rabin Desalination Laboratory, The Wolfson Faculty of Chemical Engineering, Technion - Israel Institute of Technology, Technion City 32000, Haifa, Israel.
³ Department of Chemistry and Biochemistry, The Ohio State University, Columbus 43210, OH, USA.
⁴ Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
⁵ Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH, 45221, USA.
⁶ Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China. Electronic address: cjtang@csu.edu.cn.
⁷ Institute of Environmental Engineering, School of Metallurgy and Environment, Central South University, Changsha 410083, China; Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Changsha 410083, China. Electronic address: yang220@csu.edu.cn.

PMID: 28917817
DOI: 10.1016/j.envpol.2017.09.006

Abstract

Advanced oxidation processes (AOPs) based on formation of free radicals at ambient temperature and pressure are effective for treating endocrine disrupting chemicals (EDCs) in waters. In this study, we systematically investigated the degradation kinetics of bisphenol A (BPA), a representative EDC by hydroxyl radical (OH) with a combination of experimental and theoretical approaches. The second-order rate constant (k) of BPA with OH was experimentally determined to be 7.2 ± 0.34 × 10⁹ M^-1 s^-1 at pH 7.55. We also calculated the thermodynamic and kinetic behaviors for the bimolecular reactions by density functional theory (DFT) using the M05-2X method with 6-311++G** basis set and solvation model based on density (SMD). The results revealed that H-abstraction on the phenol group is the most favorable pathway for OH. The theoretical k value corrected by the Collins-Kimball approach was determined to be 1.03 × 10¹⁰ M^-1 s^-1, which is in reasonable agreement with the experimental observation. These results are of fundamental and practical importance in understanding the chemical interactions between OH and BPA, and aid further AOPs design in treating EDCs during wastewater treatment processes.

Keywords: Bisphenol A; DFT; Hydroxyl radical; Second–order rate constants.

MeSH terms

Benzhydryl Compounds / chemistry*
Endocrine Disruptors / chemistry*
Hydroxyl Radical / chemistry*
Kinetics
Models, Chemical*
Oxidation-Reduction
Phenols / chemistry*
Thermodynamics

Substances

Benzhydryl Compounds
Endocrine Disruptors
Phenols
Hydroxyl Radical
bisphenol A