title: Mechanism and toxicity research of benzalkonium chloride oxidation in aqueous solution by H2O2/Fe(2+) process.
abstract: As widely used disinfectants, the pollution caused by benzalkonium chloride (BAC) has attracted a lot of attention in recent years. Since it is not suitable for biodegradation, BAC was degraded firstly by Fenton advanced oxidation technologies (AOTs) in this research to enhance the biodegradability of the pollutions. The result revealed that the optimal molar ratio of H2O2/Fe(2+) for BAC degradation was 10:1, and the COD removal rate was 32 %. To clarify the pathway of degradation, the technique of GC-MS was implemented herein to identify intermediates and the toxicity of those BAC intermediates were also novelty tested through microbial fuel cells (MFC). The findings indicated that ten transformation products including benzyl dimethyl amine and dodecane were formed during the H2O2/Fe(2+) processes, which means the degradation pathway of BAC was initiated both on the hydrophobic (alkyl chain) and hydrophilic (benzyl and ammonium moiety) region of the surfactant. The toxicity of BAC before and after treated by Fenton process was monitored through MFC system. The electricity generation was improved 337 % after BAC was treated by H2O2/Fe(2+) oxidation processes which indicated that the toxicity of those intermediates were much lower than BAC. The mechanism and toxicity research in this paper could provide the in-depth understanding to the pathway of BAC degradation and proved the possibility of AOTs for the pretreatment of a biodegradation process.
authors.affiliation: Department of Environmental Science and Engineering, Hua-Qiao University, Xiamen, 361021, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Environmental Science and Engineering, Hua-Qiao University, Xiamen, 361021, China.
authors.forename: Yu-Feng
authors.initials: YF
authors.lastname: Xia
authors.affiliation: Department of Environmental Science and Engineering, Hua-Qiao University, Xiamen, 361021, China. jmhong@hqu.edu.cn.
authors.forename: Jun-Ming
authors.initials: JM
authors.lastname: Hong
mesh_terms: D001548:Benzalkonium Compounds / Q000633:toxicity*; D001673:Biodegradation, Environmental; D004202:Disinfectants; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008956:Models, Chemical; D010084:Oxidation-Reduction; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D001548:Benzalkonium Compounds; D004202:Disinfectants; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical; D006861:Hydrogen Peroxide; D007501:Iron
keywords: Benzalkonium chloride; Fenton advanced oxidation technologies; Mechanism; Microbial fuel cells