壳聚糖稳定纳米铁去除地表水中Cr(Ⅵ)污染的影响因素  

EFFECT OF SOME FACTORS ON Cr(Ⅵ) REMOVAL IN SURFACE WATER BY CHITOSAN-STABILIZED NANOSCALE ZERO-VALENT IRON

作　　者：张娜[1] 耿兵[1] 李铁龙[1,2] 金朝晖[1,2] 

机构地区：[1]南开大学环境科学与工程学院,天津300071 [2]环境污染过程与基准教育部重点实验室,南开大学,天津300071

出　　处：《环境化学》2010年第2期290-294,共5页Environmental Chemistry

基　　金：天津市自然科学基金重点项目(07JCZDJC01800);教育部博士点新教师基金资助(20070055053)

摘　　要：以壳聚糖为稳定剂,制备纳米零价铁颗粒,TEM表征结果显示:其粒径分布范围为20—150 nm,平均粒径为82.4 nm.研究表明,壳聚糖稳定的纳米铁去除Cr(Ⅵ)的还原反应符合一级反应动力学方程.溶液中投加稳定剂壳聚糖,当壳聚糖浓度为150 mg.l-1时,80 min内表观一级动力学常数kobs约为空白溶液的2倍;干扰离子Ca2+,Mg2+,HCO3-和CO32-对壳聚糖稳定纳米铁去除Cr(Ⅵ)的批试验结果显示,Ca2+和Mg2+在80 min内使壳聚糖稳定纳米铁对Cr(Ⅵ)去除率分别降低了约20%和10%;HCO3-和CO32-的存在使去除率降低了约10%.Nanoscale zero-valent iron was synthesized using chitosan as a stabilizer. The results of TEM show that the size of the zero-valent iron ranges from 20 nm to 150 nm, with a mean partical size of 82.4 nm. The rate of reduction of Cr（Ⅵ） can be modelled by a pseudo-first-order reaction kinetics equation. When the concen- tration of chitosan is 150 mg · l-1 the first-order kinetic constant （kobs ） is about twice of the contorl. The existence of Ca2＋ and Mg2 ＋ decreased the Cr（Ⅵ） removal efficiency of zero-valent iron about 20% and 10%, respectively. HCO3-and CO32- decreased the Cr（Ⅵ） removal efficiency of zero-valent iron by about 10%.

关 键 词：纳米铁 地表水 六价铬 影响因素. 

分 类 号：X52[环境科学与工程—环境工程]