Fenton法与光Fenton法降解2,4-D的研究  

STUDY ON DEGRADATION OF 2,4-D BY FENTON AND PHOTO-FENTON REACTION

作　　者：孙红文[1] 吕俊岗[1] 翟洪艳[1] 

机构地区：[1]南开大学环境科学与工程学院,天津300071

出　　处：《环境化学》2005年第4期365-369,共5页Environmental Chemistry

基　　金：天津市科学基金项目(No:023605911)

摘　　要：对Fenton法与光Fenton法降解农药2,4-D进行了研究.探索了反应条件对降解效果的影响;确定了反应动力学和处理效率;同时考察了主要阴离子对反应效率的影响;以及不同条件下体系中羟自由基(·OH)的产生规律.结果表明,过氧化氢或亚铁离子的浓度过低或过高都对2,4-D的降解有不利影响,氧化剂与催化剂之间的最佳比例为5:1,最佳初始pH值在3.0-3.5之间.在最佳条件下,氧化剂与2,4-D比例为1:1时,可在10min内降解85%的农药,TOC去除率也达80%以上.引入紫外线,可在降低氧化剂剂量下达到同样效果.碳酸根和磷酸根分别在不同程度上影响2,4-D的降解效率.各种条件对体系中·OH产生效率的影响与2,4-D降解效果的变化规律一致,说明·OH是导致2,4-D降解的活性基团.Degradation of 2,4-D by Fenton and photo-Fenton reaction was studied in this paper. The influence on degradation efficiency of reaction conditions was discussed, and dynamics of the reaction and final treat efficiency were determined. Moreover, the effect of main anions on reaction efficiency was also observed. Finally, the producing rule of·OH under different conditions was studied. The results showed that adverse effects on 2,4-D degradation occurred when concentrations of H2O2 and Fe + were too high and too low, with the best ratio of H2O2 and Fe2 +being 5:1. The optimum pH occurred at 3.0-3.5. Under these optimum conditions, 85% of 2 ,4-D could be destructed in 10 min with TOC losing above 80% when the dose of the oxidant equaled to the concentration of 2,4-D. The introduction of UV could acquire the similar treatment efficiency under lower dose of Fenton reagent. The existence of carbonate and phosphate could inhibit the degradation efficiency of 2,4-D. The changing tendencies of the 2,4-D degradation efficiency and OH producing efficiency were highly comparable under different conditions, which indicated that OH was the reactive species responsible for the destruction of 2,4-D.

关 键 词：光FENTON法 TOC去除率 降解效果 反应动力学 初始PH值 氧化剂 降解农药 反应条件 处理效率 反应效率 产生规律 羟自由基 亚铁离子 过氧化氢 不利影响 最佳比例 最佳条件 降解效率 产生效率 变化规律 活性基团 离子对 催化剂 

分 类 号：X592[环境科学与工程—环境工程]