Chlorination of para-substituted phenols:Formation of α, β-unsaturated C4-dialdehydes and C4-dicarboxylic acids

作     者：Zhuoyue Zhang Carsten Prasse Zhuoyue Zhang;Carsten Prasse

作者机构：Department of Environmental Health and EngineeringJohns Hopkins UniversityBaltimoreMD 21218USA 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2022年第34卷第7期

页      面：197-208页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 0815[工学-水利工程] 

基　　金：supported by internal funding from Johns Hopkins University 

主　　题：High-resolution mass spectrometry Ring cleavage products Quantification Transformation pathways Mass balance 

摘      要：Despite the widespread occurrence of phenols in anthropogenic and natural compounds, their fate in reactions with hypochlorous acid(HOCl), one of the most common water treatment disinfectants, remains incompletely understood. To close this knowledge gap, this study investigated the formation of disinfection by-products(DBPs) in the reaction of free chlorine with seven para-substituted phenols. Based on the chemical structures of the DBPs and the reaction mechanisms leading to their formation, the DBPs were categorized into four groups: chlorophenols, coupling products, substituent reaction products, and ring cleavage products. In contrast to previous studies that investigated the formation of earlystage chlorophenols, the primary focus of this study was on the elucidation of novel ring cleavage products, in particular α, β-unsaturated C-dialdehydes, and C-dicarboxylic acids, which, for the first time, were identified and quantified in this study. The molar yields of 2-butene-1,4-dial(BDA), one of the identified α, β-unsaturated C-dialdehydes, varied among the different phenolic compounds, reaching a maximum value of 10.4% for bisphenol S. Molar yields of 2-chloromaleic acid(Cl-MA), one of the identified C-dicarboxylic acids, reached a maximum value of 30.5% for 4-hydroxy-phenylacetic acid under given conditions. 2,4,6-trichlorophenol(TCP) was shown to be an important intermediate of the parent phenols and the C-ring cleavage products. Based on the temporal trends of α, β-unsaturated C-dialdehydes and C-dicarboxylic acids, their formation is likely attributable to two separate ring cleavage pathways. Based on the obtained results, an overall transformation pathway for the reaction of para-substituted phenols with free chlorine leading to the formation of novel Cring cleavage products was proposed.