封面图片
2022年, 第16卷 第6期
Halobenzoquinones (HBQs) are not only emerging disinfection by-products (DBPs), but also precursors of other DBPs such as trihalomethanes (THMs). UV irradiation is increasingly combined with chlorine disinfection technology for treatment of drinking water, swimming pool water and wastewater, which may affect DBP formation and thus pose implications to public health and the environment. Herein, this study identified the mechanism for the promoting roles of UV irradiation and hydroxylation of HBQs play in the formation of THM DBPs by using experimental measurements and density functional theory (DFT) calculations. UV could significantly enhance the hydroxylation of dichlorobenzoquinone (DCBQ) and the formation of chloroform (CHCl3) by almost 10 times, mainly due to the production of OH-DCBQ*. The excited DCBQ* by UV could benefit nucleophilic hydrolysis to produce OH-DCBQ*, which favored electrophilic attack by chlorine, thereby inducing more THMs formation. Hydroxylation of tetrachlorobenzoquinone (TCBQ) and UV irradiation were both important in promoting THMs formation due to the high electrophilic ability of OH-TCBQ and TCBQ*. This work suggested that enhanced formation of THMs from HBQs should be considered in the application of combined UV and chlorine processes.[展开] ...
ISSN 2095-2201N (Print)
ISSN 2095-221X (Online)
CN 10-1013/X
Postal Subscription Code 80-973
原刊名 Frontiers of Environmental Science & Engineering in China 2018 Impact Factor: 3.883