针对Fenton反应过程中生成的Fe³⁺的还原速率相对于Fe²⁺和H₂O₂的反应速率较慢限制了其降解效率的问题,以N,N-二乙基-间甲苯酰胺(DEET)为目标污染物,比较了3种络合剂对Fenton反应的促进效应。结果表明,在DEET浓度为200 μmol/L、H₂O₂/Fe²⁺摩尔比为20∶1、初始Fe²⁺浓度为50 μmol/L、没食子酸(GA)/Fe²⁺摩尔比为1∶1以及pH=7.0的条件下,DEET的去除效率在20 min内达到75.3%。与传统的Fenton体系相比,DEET的降解效率提高了63.8%。HO·是加速DEET降解和矿化的主要活性氧物质。GA促进了Fe³⁺的还原和H₂O₂的分解,从而促进了额外自由基的生成,加速了Fe²⁺/H₂O₂体系对DEET的降解。

The reduction rate of Fe³⁺ generated in Fenton process is relatively slower than the reaction rate between Fe²⁺ and H₂O₂,which limits the degradation efficiency of Fe³⁺.Taking N,N-diethyl-m-toluamide (DEET) as the target pollutant,the promoting effects of three complexing agents on Fenton reaction are compared.Studies show that the removal efficiency of DEET reaches 75.3% within 20 min under the conditions that DEET concentration is 200 μmol·L^-1,the molar ratio of H₂O₂/Fe²⁺ is 20∶1,the initial concentration of Fe²⁺ is 50 μmol·L^-1,the molar ratio of gallic acid /Fe²⁺ is 1∶1 and pH=7.0.Compared with the traditional Fenton system,the degradation efficiency of DEET is 63.8% higher.HO· is the main active oxygen species that accelerates DEET to degrade and mineralize.Gallic acid promotes the reduction of Fe³⁺ and the decomposition of H₂O₂,thus promoting the generation of additional free radicals and accelerating the degradation of DEET in Fe²⁺/H₂O₂ system.

李明慧(1998-),女,硕士生,研究方向为高级氧化法处理工业废水,924516743@qq.com;李海松(1980-),男,博士,教授,研究方向为市政污水深度脱氮,通讯联系人,lhs@zzu.edu.cn。