摘要
以气体扩散电极为阴极,以Ti/SnO2-Sb2O5-IrO2为阳极,构建了电-Fenton氧化系统降解水中2,4-DCP(2,4-二氯酚),在考察气体扩散阴极产生H2O2适宜电位基础上,研究了初始c(Fe2+)和电化学反应时间对2,4-DCP降解的影响以及反应过程中c(H2 O2)、c(Fe2+)和ρ(Cl-)的变化.结果表明:该方法联合了电-Fenton氧化和钛基氧化物阳极氧化2种作用共同降解2,4-DCP,在阴极电位为-0.7 V、c(Fe2+)为0.15 mmol/L、反应60 min时,2,4-DCP去除率为89.1%;反应120 min时,2,4-DCP的吸收特征峰完全消失,去除率达到100%;反应240 min时,ρ(TOC)降至9.15 mg/L,去除率达79.4%.反应体系中ρ(H2O2)与ρ(Fe2+)呈负相关.2,4-DCP被降解后,其苯环上的氯主要以Cl-的形式存在于溶液中.
An eleetro-Fenton oxidation system using a gas diffusion electrode as the cathode and Ti/SnO2-Sb2O5-IrO2 as the anode was constructed and used for the degradation of 2,4-dichlorophenol （2,4-DCP）. Based on an investigation of the optimal potential for the gas diffusion electrode to generate H202, the effects of Fe2＋ and reaction time on the degradation of 2,4-DCP were studied. Moreover, the variations of H2O2, Fe2＋ and CI- concentrations during 2,4-DCP degradation were also investigated. The results showed that the degradation of 2,4-DCP was attributed to the co-action of electro-Fenton oxidation and anodic oxidation. Under the cathodic potential of -01 7 V, Fe2＋ concentration of 0. 15 mmol/L and reaction time of 60 minutes, 89. 1% of 2,4-DCP was removed. The characteristic absorption peak of 2,4-DCP disappeared completely, and the 2,4-DCP removal rate reached 100% after 120 minutes of treatment. TOC concentration was reduced to 9.15 mg/L, and its removal rate reached 79.4% after 240 minutes of treatment. There was a negative correlation between H2O2 and Fe2＋. After degradation, the chlorine in the molecule of 2,4-DCP existed in the form of Cl- in the solution.
出处
《环境科学研究》
EI
CAS
CSCD
北大核心
2012年第9期1041-1046,共6页
Research of Environmental Sciences
基金
国家自然科学基金项目(50808103)
