类Fenton降解对氯苯酚中Fe^(3+)的还原——两种途径及其作用  

Reduction of Fe^(3+)during 4-chlorophenol degradation by Fenton-like process:Role of two reduction pathways

作　　者：杜瑛珣[1] 年跃刚[2] 周明华[1] 雷乐成[1] 

机构地区：[1]浙江大学环境工程研究所,浙江杭州310027 [2]中国环境科学研究院生态环境研究所,北京100012

出　　处：《浙江大学学报（工学版）》2005年第10期1618-1622,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(20176053)

摘　　要：为更好的了解类Fenton体系降解对氯苯酚(4-CP)过程Fe2+的来源,考察了过程中Fe2+的变化并分析了两种Fe3+还原途径.Fe2+的生成分成3个阶段:缓慢增加、快速增加和停止增加;Fe3+还原存在两种途径:H2O2的还原作用(A)和中间产物对苯二酚对Fe3+的还原(B).实验数据拟合表明Fe3+被对苯二酚还原的速率与溶液中Fe3+的浓度的平方成正比,与对苯二酚浓度成正比,反应速率常数为4.96×105(mol/L)-2.s-1.降解过程中,两种还原途径交互起作用.反应启动时,A途径起着关键作用并导致B途径的产生;降解12 min后,B途径居主导地位,20 min后,A途径的作用可忽略不计.To better understand the source of Fe^2＋ during the degradation of 4-chlorophenol （4-CP） by Fenton-like process better, change of Fe^2＋ was measured during the whole course and two reduction pathways of Fe^3＋ were analyzed. Formation of Fe^2＋ was divided into three phases： slow phase, fast phase and the phase in which no Fe^2＋ formed. Fe^3＋ is not only reduced by hydrogen peroxide （pathway A） but by the intermediate- hydroquinone （pathway B）. The experimental data showed that the reduction rate of Fe^3＋ by hydroquinone was first order to the concentration of 4-CP and second order to the concentration of Fe^3＋. The rate constant is 4.96×10^5 （mol/L）^-2·s^-1. These two pathways interact during the degradation of 4- CP. At the time when the reaction starts, pathway is very important and gives rise to pathway B. But after 12 min, pathway pathnay B becomes dominant and pathway A can be neglected after 20 min.

关 键 词：类FENTON 对氯苯酚 对苯二酚 H2O2 Fe^3+还原 

分 类 号：X783[环境科学与工程—环境工程]