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%.
出处
《环境化学》
CAS
CSCD
北大核心
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)
关键词
纳米铁
地表水
六价铬
影响因素.
nanoscale zero-valent iron, surface water, hexavalent chromium, influential factors.
