EDTA催化Fe^(3+)/H_2O_2降解水中孔雀石绿  

Degradation of Malachite Green in Aqueous Solution by Fe^(3+)/H_2O_2 Catalyzed with EDTA

作　　者：李春娟[1] 马军[1] 余敏[1] 张瑛洁[1] 

机构地区：[1]哈尔滨工业大学市政环境工程学院,哈尔滨150090

出　　处：《环境科学》2008年第5期1255-1260,共6页Environmental Science

基　　金：教育部科技创新重大项目培育基金项目(705013)

摘　　要：以孔雀石绿(malachite green,MG)为目标物,在pH=7的中性条件下,考察EDTA对Fe3+/H2O2降解水中孔雀石绿的影响,发现EDTA很大程度地促进了Fe3+/H2O2对孔雀石绿的降解.EDTA的加入可以使MG的脱色率由43%升至98.3%.在本实验条件下,EDTA的投加量增加5倍时,MG的脱色率上升40%.随着H2O2投量的增加,MG的脱色率显著上升.随着温度的升高,MG的脱色率显著上升.叔丁醇的加入抑制了EDTA对Fe3+/H2O2降解孔雀石绿的催化效果.总量相同H2O2的多次投加并未获得明显优于一次投加的去除效果.EDTA催化Fe3+/H2O2降解水中孔雀石绿并不遵循简单的羟基自由基机理,同时存在的中间价态铁的物种起着主要的氧化作用.随着反应的进行,EDTA被部分降解.This study found that the discolorization of malachite green solutions （0.01 mmol/L） was improved by Fe^3＋/H2 O2 catalyzed with EDTA, at pH 7. Oxidation was carried out in presence of various hydrogen peroxide concentrations, in a wide range of temperature and EDTA concentration. It was found that oxidation with EDTA promoted the discolorization of MG from 43 % to 98.3 % as compared with the cases without EDTA. The discolorization of MG increased by 40% with the increase of EDTA concentration by 5 fold. The H2 02 concentration and temperature are higher, the discolorization of MG better, t-BuOH inhibited the improvement from EDTA. With the same total dosage of applied H2 O2, the multiple steps addition did not show a much higher removal efficiency than that obtained by one step. OH free radical or an iron-oxo species may be the highly reactive oxidizing species, the latter may be the major oxidant. With the time, EDTA was a little oxidized.

关 键 词：EDTA 催化 类芬顿体系 孔雀石绿 降解 中间价态铁 

分 类 号：X703.1[环境科学与工程—环境工程]