title: Enhanced AOX accumulation and aquatic toxicity during 2,4,6-trichlorophenol degradation in a Co(II)/peroxymonosulfate/Cl⁻ system.
abstract: Chloride ion is known to affect on degradation kinetics in different ways during HO· and SO4(·-)-based advanced oxidation processes (AOPs). However, its effect on absorbable organic halogen (AOX) evolution and acute toxicity of treated water remains unknown, despite the importance of the two parameters in evaluating the applicability of AOPs. In the present study, Co/peroxymonosulfate (Co/PMS) and UV/hydrogen peroxide (UV/H2O2) treatment of 2,4,6-trichlorophenol was compared in terms of AOX formation, chlorinated byproducts and acute toxicity. Both Co/PMS and UV/H2O2 systems were more reactive under acidic conditions, resulting in elevated AOX levels when compared with those at neutral pH. The presence of high levels of chloride led to an accumulation and increase of AOX in the Co/PMS system. The toxicity of chlorinated byproducts was evaluated using Photobacterium phosphoreum, and the results revealed a sharp increase in acute toxicity of Co/PMS reaction solutions on addition of chloride ion. However, addition of Cl(-) had no apparent impact on AOX and toxicity of UV/H2O2 reaction solutions. These findings may have significant technical implications for selecting feasible technologies to treat high salinity wastewater.
authors.affiliation: State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.
authors.forename: Changling
authors.initials: C
authors.lastname: Fang
authors.affiliation: State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.
authors.forename: Dongxue
authors.initials: D
authors.lastname: Xiao
authors.affiliation: State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.
authors.forename: Wenqian
authors.initials: W
authors.lastname: Liu
authors.affiliation: State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.
authors.forename: Xiaoyi
authors.initials: X
authors.lastname: Lou
authors.affiliation: State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.affiliation: State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; Southern Cross GeoScience, Southern Cross University, Lismore, NSW 2480, Australia. Electronic address: zhaohuiwang@dhu.edu.cn.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Wang
authors.affiliation: State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China. Electronic address: liujianshe@dhu.edu.cn.
authors.forename: Jianshe
authors.initials: J
authors.lastname: Liu
mesh_terms: D002712:Chlorides / Q000737:chemistry*; D002733:Chlorophenols / Q000737:chemistry / Q000633:toxicity*; D003035:Cobalt / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry; D010776:Photobacterium / Q000187:drug effects*; D014466:Ultraviolet Rays; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity*
chemical_list: D002712:Chlorides; D002733:Chlorophenols; D003035:Cobalt; D006861:Hydrogen Peroxide; D010545:Peroxides; D062065:Wastewater; D014874:Water Pollutants, Chemical; C038288:peroxymonosulfate; C024564:2,4,6-trichlorophenol
keywords: Active chlorine species; Hydroxyl radical; Polychlorinated organic compounds; Sulfate radical