摘要
采用纳米零价铁(nZVI)活化过硫酸钠产生强氧化性的硫酸根自由基(SO-4·)去除目标污染物2,4-二氯苯酚(2,4-DCP).通过比较nZVI与Fe2+催化S2O2-8对2,4-DCP的降解,结合SEM、EDS对nZVI反应前后表面结构变化分析发现,nZVI在过硫酸盐氧化降解2,4-DCP中主要起到Fe2+离子源的作用,也具有还原和吸附作用.深入研究不同因素(初始pH值、nZVI投加量、S2O2-8初始浓度、2,4-DCP初始浓度)对2,4-DCP降解的影响,结果表明降低溶液初始pH值能提高nZVI/S2O2-8对2,4-DCP的降解率.在2,4-DCP初始浓度为30 mg·L-1,S2O2-8浓度为12.5 mmol·L-1,nZVI为2.0 g·L-1,pH值为3.0,温度为30℃下,2,4-DCP的去除率能达到92.1%,其降解过程符合准一级动力学,表观活化能为91.48 kJ·mol-1,是表面控制过程.
Nanoscale zero-valent iron （ nZVI ） was used as catalyst for persulfate oxidation of 2,4-dichlorophenol （2,4-DCP） to understand the roles of nZVI in generation of sulfate radicals. The results obtained from SEM and EDS demonstrate that changes on the surfaces of the nZVI were observed due to the Fe2＋leaching, adsorption of organic matter and oxidation. In addition, the effects of initial pH, nZVI dosage, initial concentrations of persulfate and 2,4-DCP, temperature on the degradation of 2,4-DCP were investigated. The results indicated that 2,4-DCP removal efficiency increased with decreasing pH. When the concentration of DCP, S2 O2-8 , nZVI were 30 mg·L-1, 12.5 mmol·L-1, 2.0 g·L-1, the removal efficiency of 2,4-DCP reached 92.1%. The degradation process of 2,4-DCP conformed to the pseudo first-order kinetics. It was proposed to be a surface-controlled process with activation energy of 91.48 kJ·mol-1 .
出处
《环境化学》
CAS
CSCD
北大核心
2014年第5期812-818,共7页
Environmental Chemistry
基金
福建师范大学"闽江学者"人才建设项目
福建省教育厅资助项目(JA13071)资助
关键词
过硫酸盐
纳米零价铁
2
4-二氯苯酚
氧化降解
sulfate radical anion
nanoscale zero-valent iron
2,4-dichlorophenol
oxidation
