title: Degradation of carbamazepine by UV/chlorine advanced oxidation process and formation of disinfection by-products.
abstract: Pharmaceuticals in water are commonly found and are not efficiently removed by current treatment processes. Degradation of antiepileptic drug carbamazepine (CBZ) by UV/chlorine advanced oxidation process was systematically investigated in this study. The results showed that the UV/chlorine process was more effective at degrading CBZ than either UV or chlorination alone. The CBZ degradation followed pseudo-first order reaction kinetics, and the degradation rate constants (kobs) were affected by the chlorine dose, solution pH, and natural organic matter concentration to different degrees. Degradation of CBZ greatly increased with increasing chlorine dose and decreasing solution pH during the UV/chlorine process. Additionally, the presence of natural organic matter in the solution inhibited the degradation of CBZ. UV photolysis, chlorination, and reactive species (hydroxyl radical •OH and chlorine atoms •Cl) were identified as responsible for CBZ degradation in the UV/chlorine process. Finally, a degradation pathway for CBZ in the UV/chlorine process was proposed and the formation potentials of carbonaceous and nitrogenous disinfection by-products were evaluated. Enhanced formation of trichloroacetic acid, dichloroacetonitrile, and trichloronitromethane precursors should be considered when applying UV/chlorine advanced oxidation process to drinking water.
authors.affiliation: Department of Water Engineering and Science, College of Civil Engineering, Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Hunan University, Changsha, Hunan, 410082, People's Republic of China. shiqingzhouwater@163.com.
authors.forename: Shiqing
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Department of Water Engineering and Science, College of Civil Engineering, Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Hunan University, Changsha, Hunan, 410082, People's Republic of China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Xia
authors.affiliation: Department of Water Engineering and Science, College of Civil Engineering, Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Hunan University, Changsha, Hunan, 410082, People's Republic of China.
authors.forename: Ting
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Water Engineering and Science, College of Civil Engineering, Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Hunan University, Changsha, Hunan, 410082, People's Republic of China.
authors.forename: Tian
authors.initials: T
authors.lastname: Yao
authors.affiliation: Department of Water Engineering and Science, College of Civil Engineering, Key Laboratory of Building Safety and Energy Efficiency, Ministry of Education, Hunan University, Changsha, Hunan, 410082, People's Republic of China.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China.
authors.forename: Shumin
authors.initials: S
authors.lastname: Zhu
authors.affiliation: State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, People's Republic of China.
authors.forename: Naiyun
authors.initials: N
authors.lastname: Gao
mesh_terms: D000927:Anticonvulsants; D002220:Carbamazepine / Q000032:analysis / Q000737:chemistry*; D002713:Chlorine / Q000737:chemistry*; D004202:Disinfectants / Q000032:analysis / Q000737:chemistry*; D004203:Disinfection / Q000379:methods; D054879:Halogenation; D006843:Hydrocarbons, Chlorinated; D017665:Hydroxyl Radical; D007477:Ions; D007700:Kinetics; D008956:Models, Chemical; D010084:Oxidation-Reduction; D010782:Photolysis; D014466:Ultraviolet Rays; D014867:Water; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
chemical_list: D000927:Anticonvulsants; D004202:Disinfectants; D006843:Hydrocarbons, Chlorinated; D007477:Ions; D014874:Water Pollutants, Chemical; D014867:Water; D017665:Hydroxyl Radical; D002220:Carbamazepine; D002713:Chlorine; C100187:chloropicrin
keywords: Carbamazepine; Disinfection by-product; Kinetics; Oxidation; UV/chlorine