Fe^(2+)/S_2O_8^(2-)/EDTA体系中自由基离子对啶虫脒的氧化降解  

Chemical Oxidation Degradation of Acetamiprid by Radical Ions in Fe^(2+)/S_2O_8^(2-)/EDTA Aqueous Solution

作　　者：阳海[1] 黎源[1] 徐淼[1] 刘华杰[1] 庞怀林[2] 张冠杰[1] 易兵[1] 

机构地区：[1]湖南工程学院化学化工学院,生态纺织材料及染整新技术湖南省高校重点实验室,湖南湘潭411104 [2]湖南化工研究院,国家农药创制工程技术研究中心,湖南长沙410007

出　　处：《环境科学研究》2014年第3期321-327,共7页Research of Environmental Sciences

基　　金：国家自然科学基金项目(21207034);湖南省产业培育化项目(11CY007);湖南省教育厅重点项目(10A022)

摘　　要：为探讨水环境中自由基离子对啶虫脒的共降解作用,研究了Fe2+S2O82-EDTA体系中啶虫脒降解的可行性,以及在Fe2+S2O82-EDTA体系中3种组分最佳配比条件下自由基离子和底物浓度对啶虫脒降解率的影响.结果表明,在Fe2+S2O82-EDTA体系下反应360 min后啶虫脒的降解率达到58.25%,c(Fe2+)、c(S2O82-)和c(EDTA)对Fe2+S2O82-EDTA体系的氧化能力均有较大的影响.通过中心复合试验对Fe2+S2O82-EDTA体系中3种离子的最佳配比进行优化,c(EDTA)、c(Fe2+)、c(S2O82-)分别为1.61、3.46、7.99 mmolL.Fe2+S2O82-EDTA体系中·SO4-和·OH等自由基离子的存在是引起啶虫脒降解的主要原因,中性条件最有利于自由基离子的产生并提高啶虫脒高的降解率.然而该体系中自由基离子的量是一定的,过高的c(啶虫脒)(>200μmolL)对降解率有明显抑制.Acetamiprid used in plant and soil has widely drawn more and more attentions due to its actions type and environmental toxicity in recent years. In order to probe the environmental transformation characteristic, the chemical oxidation degradation kinetics of acetamiprid were carried out in Fe2＋/S2O82-/EDTA aqueous solution. Various parameters such as the concentration of Fe2＋/S2O82- and EDTA, affecting on degradation efficiencies were investigated by single-variable-at-a-time （SVAT） and central composite design （CCD） based on response surface methodology （ RSM ）. The results showed that the degradation efficiency of acetamiprid was achieved as 58.25% after 360 minutes reaction. The oxidizing ability of Fe2＋/S2O82-/EDTA was significantly affected by the concentration of Fe2＋/S2O82-and EDTA, respectively. The degradation optimum conditions of acetamiprid were obtained by CCD as follows： EDTA as 1.61 mmol/L, Fe2＋ as 3.46 mmol/L and S2O82- as 7.99 mmol/L in Fe2＋/S2O82-/EDTA aqueous solution. Additionally, the degradation efficiencies of acetamiprid were attributed to reactive oxidation species （ROSs） , and the neutral solution was favor for generating ROSs in Fe2＋/S2O82-/EDTA aqueous solution. However, due to certain amounts of ROSs in Fe2＋/S2O82-/EDTA aqueous solution, the higher concentration of aeetamiprid （ 〉 200 μmol/L ） retard its degradation obviously, and then lead to lower degradation efficiencies. These results provide fundamental information necessary for the environmental transformation characteristic by ROSs in environmental water.

关 键 词：啶虫脒 氧化降解 FE^2+ S2O8^2- EDTA体系 自由基离子 

分 类 号：X592[环境科学与工程—环境工程]