title: Organic pollutants removal in wastewater by heterogeneous photocatalytic ozonation.
abstract: Heterogeneous photocatalysis and ozonation are robust advanced oxidation processes for eliminating organic contaminants in wastewater. The combination of these two methods is carried out in order to enhance the overall mineralization of refractory organics. An apparent synergism between heterogeneous photocatalysis and ozonation has been demonstrated in many literatures, which gives rise to an improvement of total organic carbon removal. The present overview dissects the heterogeneous catalysts and the influences of different operational parameters, followed by the discussion on the kinetics, mechanism, economic feasibility and future trends of this integrated technology. The enhanced oxidation rate mainly results from a large amount of hydroxyl radicals generated from a synergistically induced decomposition of dissolved ozone, besides superoxide ion radicals and the photo-induced holes. Six reaction pathways possibly exist for the generation of hydroxyl radicals in the reaction mechanism of heterogeneous photocatalytic ozonation.
authors.affiliation: National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Beijing 100190, China; Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Jiadong
authors.initials: J
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; Beijing Engineering Research Center of Process Pollution Control, Beijing 100190, China. Electronic address: ybxie@ipe.ac.cn.
authors.forename: Yongbing
authors.initials: Y
authors.lastname: Xie
authors.affiliation: National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Beijing 100190, China; Beijing Engineering Research Center of Process Pollution Control, Beijing 100190, China. Electronic address: hbcao@ipe.ac.cn.
authors.forename: Hongbin
authors.initials: H
authors.lastname: Cao
mesh_terms: D002384:Catalysis; D017665:Hydroxyl Radical / Q000737:chemistry; D007700:Kinetics; D009930:Organic Chemicals / Q000032:analysis*; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D055668:Photochemical Processes; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods*
chemical_list: D017665:Hydroxyl Radical; D009930:Organic Chemicals; D010126:Ozone; D062065:Wastewater; D014874:Water Pollutants, Chemical
keywords: Catalyst; Mechanism; Photocatalytic ozonation; Wastewater treatment