不同螯合剂对零价铁活化过硫酸盐降解对氯苯胺的影响  

Effect of chelating agents on the degradation of p-chloroaniline in Fe^0-persulfate system

作　　者：钟燕清[1] 张永清[1] 陈宪方 黄少斌[1] 

机构地区：[1]华南理工大学环境与能源学院,广州510006

出　　处：《环境化学》2015年第4期685-691,共7页Environmental Chemistry

基　　金：制浆造纸工程国家重点实验室开放基金资助项目(201477);亚热带建筑科学国家重点实验室开放基金资助项目(2015ZB25);广东省大气环境与污染控制重点实验室开放基金资助项目(2011A060901011);国家自然科学基金(51378217;U1360101)资助

摘　　要：研究了螯合剂EDTA、草酸(OA)、柠檬酸(CA)以及2,2-联吡啶(BPY)对零价铁(ZVI)活化过硫酸盐(PS)降解对氯苯胺(PCA)的影响;考察了溶液中PCA的降解率、PS消耗量和溶液中的Fe2+含量对反应的影响.结果表明,在中性条件下,EDTA、OA、CA等3种螯合剂抑制PCA在零价铁活化过硫酸盐体系中降解.而BPY促进了PCA的降解,增加溶液中BPY浓度,PCA的降解率增大;且PCA的降解是拟一级反应,其速率和BPY浓度呈正比;溶液初始p H值为3.0—11.0时,PCA在中性和碱性条件下的降解效率高于酸性条件.相对未加入BPY的体系,在中性和碱性条件下,BPY促进ZVI中Fe2+的溶出而提高PS活化效率,在酸性条件下,BPY由于减少了溶液中游离的Fe2+浓度,表现出对PCA的降解抑制.本文结果进一步证明了零价铁活化过硫酸盐非均相体系中,零价铁是作为活化PS的Fe2+的替代来源.This article investigated the degradation of p-chloroaniline （ PCA） in aqueous solution by persulfate （ PS） activated with zero valent iron in the presence of chelating agents such as EDTA, oxalic acid （ OA） , citric acid （ CA） and 2, 2-pyridine （ BPY）; The effects of Fe^2＋ concentration, PCA degradation rate, PS consumption and Fe^2＋ contents were discussed. The results showed that the degradation of PCA was inhibited by EDTA, OA and CA under neutral conditions in PS-ZVI system. The degradation of PCA increased with the increasing concentrations of BPY. PCA degradation is a pseudo-first-order reaction and the reaction rate is directly proportional to BPY concentration. The degradation efficiency of PCA was higher in neutral and alkaline conditions compared to acidic conditions at initial pH 3. 0—11. 0. Our study further proved that ZVI-PS is a heterogeneous system and ZVI is the source of Fe^2＋ for PS activation.

关 键 词：螯合剂 对氯苯胺 过硫酸盐 零价铁 硫酸根自由基 

分 类 号：X703[环境科学与工程—环境工程]