Oxygen dependent oxidation of trimethoprim by sulfate radical:Kinetic and mechanistic investigations  

作　　者：Xuerui Yang Xi Ding Lei Zhou Yuefei Ji Guangli Xiu 

机构地区：[1]Shanghai Environmental Protection Key Laboratory for Environmental Standard and Risk Management of Chemical Pollutants,School of Resources&Environmental Engineering,East China University of Science and Technology,Shanghai 200237,China [2]State Environmental Protection Key Lab of Environmental Risk Assessment and Control on Chemical Processes,School of Resources&Environmental Engineering,East China University of Science and Technology,Shanghai 200237,China [3]Shanghai Institute of Pollution Control and Ecological Security,Shanghai 200092,China [4]College of Resources and Environmental Sciences,Nanjing Agricultural University,Nanjing 210095,China

出　　处：《Chinese Chemical Letters》2021年第10期3164-3168,共5页中国化学快报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.21806037)。

摘　　要：Trimethoprim(TMP)is a typical antibiotic to treat infectious disease,which is among the most commonly detected antibacterial agents in natural waters and municipal wastewaters.In the present study,the impacts of dissolved oxygen(DO)on the oxidation efficiency and pathways of TMP by reaction with sulfate radicals(SO_(4)^(-1))were investigated.Our results revealed that the presence of DO was favourable for TMP degradation.Specifically,TMP would react initially with SO_(4)^(-1)via electron-transfer process to form a carbon-centered radical.In the absence of oxygen,the carbon-centered radical could undergo hydrolysis to produceα-hydroxytrimethoprim(TMPàOH),followed by the further oxidation which generatedα-ketotrimethoprim(TMP=O).However,in the presence of oxygen,the carbon-centered radical would alternatively combine with oxygen,leading to a sequential reaction in which peroxyl radical and a tetroxide were formed,and finally generated TMPàOH and TMP=O simultaneously.The proposed pathways were further confirmed by density functional theory(DFT)calculations.The results obtained in this study would emphasize the significance of DO on the oxidation of organic micropollutants by SO_(4)^(-1).

关 键 词：ANTIBIOTICS Sulfate radicals Dissolved oxygen HYDROXYLATION DFT calculations 

分 类 号：X703[环境科学与工程—环境工程] O643.1[理学—物理化学]