Chemical reductive technologies for the debromination of polybrominated diphenyl ethers: A review

作     者：Ming Lei Yao Tang Lihua Zhu Heqing Tang Ming Lei;Yao Tang;Lihua Zhu;Heqing Tang

作者机构：College of Resources and Environmental ScienceSouth-Central Minzu UniversityWuhan 430074China School of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China 

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

年 卷 期：2023年第127卷第5期

页      面：42-59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）] 082803[工学-农业生物环境与能源工程] 08[工学] 0828[工学-农业工程] 

基　　金：supported by the National Natural Science Foundation of China(Nos.21707170,21777194 and 22076052) the Natural Science Foundation of Hubei Province(No.2021CFB535) the Fundamental Research Funds for the Central Universities of South-Central MinZu University(No.CZT20019). 

主　　题：Polybrominated diphenyl ethers (PBDEs) Debromination Chemical reduction Electron transfer Hydrogenation 

摘      要：Polybrominated diphenyl ethers(PBDEs)are widely used as brominated flame retardants,which had attracted amounts of attention due to their harmful characteristics of high toxicity,environmental persistence and potential bioaccumulation.Many chemical reductive debromination technologies have been developed for the debromination of PBDEs,including photolysis,photocatalysis,electrocatalysis,zero-valent metal reduction,chemically catalytic reduction and mechanochemical method.This review aims to provide information about the degradation thermodynamics and kinetics of PBDEs and summarize the degradation mechanisms in various systems.According to the comparative analysis,the rapid debromination to generate bromine-free products in an electron-transfer process,of which photocatalysis is a representative one,is found to be relatively difficult,because the degradation rate of PBDEs depended on the Br-rich phenyl ring with the lowest unoccupied molecular orbital(LUMO)localization.On the contrary,the complete debromination occurs easily in other systems with active hydrogen atoms as the main reactive species,such as chemically catalytic reduction systems.The review provides the knowledge on the chemical reductive technique of PBDEs,which would greatly help not only clarify the degradation mechanism but also design the more efficient system for the rapid and deep debromination of PBDEs in the future.