纳米铁对水中Cr(Ⅵ)和p-NCB的同步修复机制  

Simultaneous Remediation of Cr(Ⅵ) and p-NCB by Nanosacle Iron

作　　者：牛少凤[1] 李春晖[2] 楼章华[1] 许月萍[1] 

机构地区：[1]浙江大学建筑工程学院,杭州310027 [2]北京师范大学环境学院、水沙科学教育部重点实验室,北京100875

出　　处：《环境科学》2009年第1期146-150,共5页Environmental Science

基　　金：国家自然科学基金项目(50709002,20407015)

摘　　要：采用化学沉淀法制备纳米级Fe和纳米级Ni/Fe,利用制备的纳米催化剂对六价铬[Cr(Ⅵ)]与对硝基氯苯(p-NCB)进行同步修复研究.主要探讨纳米级Fe及纳米级Ni/Fe对Cr(Ⅵ)和p-NCB同步修复过程中,受污染水体中Cr(Ⅵ)和对硝基氯苯(p-NCB)的相互影响.实验表明,纳米级Fe可将p-NCB降解为对氯苯胺(p-CAN),并不能进一步脱氯,Cr(Ⅵ)与p-NCB的降解存在着竞争关系.纳米级Ni/Fe双金属应用于p-NCB和Cr(Ⅵ)同步修复,可以取得良好的修复效率,反应产物为Cr(Ⅲ)和苯胺,并不产生中间产物.Ni(Ⅱ)浓度的增加,可以促进脱氯反应的进行,最佳Ni/Fe质量比为1∶50.而Cr(Ⅵ)、p-NCB初始浓度增加会导致脱氯率的下降.Cr(Ⅵ)浓度为20 mg/L时,对应的最大脱氯效率为43.0%,而p-NCB的浓度为40 mg/L时,对应的六价铬还原效率为71.4%.Nanoscale Fe and Ni/Fe, which were prepared by chemical deposition, were utilized as catalyst for remediation of Cr（ Ⅵ ） and p- NCB in contaminated water. The interactions between Cr（ Ⅵ ） and p-NCB in contaminated water during the simultaneous remediation process were analyzed. It is demonstrated from the experiment that p-NCB can be degradated into p-CAN by nanoscale iron, but cannot exhibit the effect of dechlorination, and that there is a competitive relationship between Cr（ Ⅵ ） and p-NCB in the remediation process. The nanoscale Ni/ Fe bimetals could be applied in simultaneous remediation of p-NCB with Cr（ Ⅵ ） and give rise to a good remediation efficiency, where the products are only Cr（ Ⅲ ） and p-CAN without any intermediate products. It was found that the conditions of higher Ni（ Ⅱ ） concentration can promote the degradation rate of p-NCB. The optimum Ni/Fe ratio is 1：50. Whereas, the higher concentrations of Cr（ Ⅵ ） and p-NCB will lead to the lower degradation rate. Under the condition that concentration of Cr （Ⅵ） was 20 mg/L, the corresponding maximum dechlorination of p-NCB was 43.0% ; under the condition that concentration of p-NCB was 40 mg/L, the corresponding maximum removal efficiency of Cr（Ⅵ ）was 71.4%.

关 键 词：纳米铁 Cr(Ⅵ) p-NCB 同步修复 

分 类 号：X52[环境科学与工程—环境工程]