污染控制技术及原理
吴进华,李小明,曾光明,杨麒,黄昱,易婷.含乐果废水的循环电-Fenton氧化过程及其影响因素[J].环境科学学报,2008,28(8):1534-1541
含乐果废水的循环电-Fenton氧化过程及其影响因素
- Oxidation treatment of dimethoate-containing wastewater by a circulating electro fenton method
- 基金项目：国际科技合作重点项目(No2004DFA06200);新世纪优秀人才支持计划资助(NoNCET-04-0770)
- 作者
- 单位
- 吴进华
- 湖南大学环境科学与工程学院, 长沙 410082
- 李小明
- 湖南大学环境科学与工程学院, 长沙 410082
- 曾光明
- 湖南大学环境科学与工程学院, 长沙 410082
- 杨麒
- 湖南大学环境科学与工程学院, 长沙 410082
- 黄昱
- 湖南大学环境科学与工程学院, 长沙 410082
- 易婷
- 湖南大学环境科学与工程学院, 长沙 410082
- 摘要：为克服传统Fenton(Conventional Fenton,简称CF)法中存在着Fe2+在反应初始时即被氧化且反应过程中产生大量铁泥(Fe的复杂络合物)的不足,研究了循环电-Fenton(Circulating Electro Fenton,简称CEF-FeRe)法氧化降解自配乐果废水的过程及其各影响因子的作用机制.CEF-FeRe反应所需的H2O2通过蠕动泵缓慢加入到电解池中,而被氧化了的Fe2+又在阴极被还原,使得Fenton反应能持续进行.在乐果浓度为200mg·L-1时,通过多个单因素试验确定最佳CEF-FeRe反应条件为:常温、pH值为3.0、H2O2/Fe2+的摩尔比为10、H2O2的加入量为理论剂量、恒流0.5A.结果表明,在此条件下反应120min后COD去除率为81.67%,乐果在25min内去除率为99.4%.通过测定CEF-FeRe以及CF反应过程中Fe2+和H2O2的变化情况验证了CEF-FeRe反应的机理.动力学研究结果表明,乐果废水的CEF-FeRe反应符合一级动力学反应规律.CEF-FeRe法处理实际乐果废水也可以得到91.16%的乐果去除及68.53%的COD去除,这表明CEF-FeRe法处理乐果废水效率高且运行费用较低的特点.
- Abstract：The main disadvantage of Conventional Fenton (CF) treatment is the lack of Fe2+ due to the rapid oxidation of Fe2+ to Fe3+.To solve this problem,a Circulating Electro-Fenton reactor (CEF-FeRe) was employed to degrade dimethoate,during which H2O2 was added to the electrolytic cell continuously by a peristaltic pump and Fe2+ could be regenerated to Fe3+ on the cathode. The operating conditions for this CEF-FeRe,such as pHvalue,electric current,Fenton reagent dosage,and the molar ratio of Fe2+ to H2O2,were optimized by individual factor experiments. The research results showed that the optimal conditions for dimethoate (200 mg·L-1) degradation are: pH=3.0,n(Fe2+)/n(H2O2)=0.1,electric current=0.5 Aand Fenton's reagent dosage at its theoretical dosage. Under these conditions,CODremoval rates reached 81.67% within120 min,while 99.4% of dimethoate was degraded within 25min. The mechanism of the CEF-FeRe reaction was investigated by monitoring the changes of H2O2 and Fe2+ concentration during the process. Kinetics results revealed that dimethoate oxidation follows the pseudo-first-order kinetic model at different pHvalues. Treatment of actual dimethoate wastewater by the CEF-FeRe showed that the removal rates of dimethoate and COD were about 91.16% and 68.53%,respectively,which indicated that the CEF-FeRe could be a cost-efficient method for dimethoate degradation.
摘要点击次数： 2909 全文下载次数： 2911
