改性阴极强化电芬顿降解污水处理厂出水中的新污染物  

Enhanced Degradation of Emerging Contaminants from Secondary Effluent by Electron-Fenton Using Modified Cathode

作　　者：熊艳芳 郑磊 高镱萌[2] 郝庆菊[1] 江长胜[1] XIONG Yanfang;ZHENG Lei;GAO Yimeng;HAO Qingju;JIANG Changsheng(College of Resource and Environment,Southwest University,400715;Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences,400714,Chongqing,China)

机构地区：[1]西南大学资源环境学院,400715 [2]中国科学院重庆绿色智能技术研究院,重庆400714

出　　处：《水处理技术》2023年第7期50-55,共6页Technology of Water Treatment

基　　金：国家自然科学基金资助项目(52100066,52131003);重庆市自然科学基金博士后科学基金项目(cstc2021jcyj-bshX0057);中国科学院特别研究助理资助项目。

摘　　要：研究了电芬顿对于城市污水处理厂二级出水中的7种典型新污染物(避蚊胺、西玛津、阿特拉津、敌草隆、磺胺甲恶唑、甲氧苄啶)的降解性能。探讨了氢氧化钠改性对碳毡形貌结构和产H_(2)O_(2)能力的影响;利用正交试验探究了电芬顿主要运行参数:pH、Fe^(2+)、工作电压对于体系中羟基自由基(^(·)OH)产量的影响并确定电芬顿运行最优条件。结果表明,改性碳毡由于含氧官能团的引入,表面粗糙度和亲水性增强,使得产H_(2)O_(2)能力提高;正交试验确定的最优条件为pH为3,Fe^(2+)为14 mg/L,工作电压为-2.01 V;此条件下模拟污水中的污染物降解率均在2 h内达到80%以上,而实际污水中可溶性有机物与目标污染物存在竞争效应,导致降解率降低(30%~75%);芳环上具有吸电子效应的卤素基团导致西玛津和阿特拉津在两种体系中降解率皆为最低;目标污染物在两种体系中的降解行为均遵循准一级动力学模型,且在实际污水中的降解速率常数远小于模拟污水。以上研究旨为电芬顿的实际应用提供切实可行的策略。This study investigated that the degradation of seven emerging contaminants(DEET,Simazine,Atrazine,Diuron,Sulfamethoxazole,Trimethoprim,Triclocarban)from the secondary effluent by electron-Fenton.The effects of sodium hydroxide(NaOH)modification on the morphology and structure of carbon felt were discussed and H_(2)O_(2) production of two carbon felts were also compared.The orthogonal test was conducted to optimize hydroxyl radical(^(·)OH)generation.The results demonstrated that the H_(2)O_(2) generation of carbon felt was improved by the NaOH activation due to the increase of surface roughness and hydrophilicity as well as oxygen containing group addition.The optimal conditions were obtained from the orthogonal test(pH 3,14 mg/L Fe^(2+)and-2.01 V).Degradation tests showed that the removal of each contaminant in the synthetic wastewater was over 80%within 2 h.Since the dissolved organic matters competed with the target pollutants for reacting with·OH,there was a decrease in the degradation(30%~75%).The electron-withdrawing halogen group on the aromatic ring resulted in the lowest degradation of simazine and atrazine in both conditions.The degradation process of the target contaminants followed a pseudo first-order kinetic model,and the rate constant of reaction in the secondary effluent was much smaller than that in the synthetic wastewater.This study aimed to provide a practical strategy for the practical application of electro-Fenton.

关 键 词：新污染物 电芬顿 改性碳毡 二级出水 

分 类 号：X703.1[环境科学与工程—环境工程]