第26卷第5期 2012年10月
代
质
现
地
GEOSCIENCE
Vol. 26
Na.5 Oet 2012
膨润土负载纳米铁去除地下水中六价铬研究
李晨桦，陈家玮
（中国地质大学地球科学与资源学院，北京
100083）
摘要：随着人民生活水平的提高和城市化进程的加快，有机污染物及重金属高强度场地污染对人类健康、生态环境及社会安全构成了严重威胁。地下水中的重金属Cr(VI)污染逐渐受到重视，纳米零价铁可以有效地将六价铬还原成三价铬，使其沉淀固定下来，从而将污染源区的污染物消减固定，防止其向周围扩散。然面由于纳米铁颗粒微小，易被氧化，极易团聚，自身活性受到限制，因此，纳米铁的分散性、稳定性、良好活性研究至关重要。采用低成本环境友好型粘土矿影润土作为负载材料制备膨润土负载纳米铁（B-NZV1），批实验和柱实验研究B-NZVI去除模拟地下水中Cr（VI）。结果表明：（1)自制的润土负载纳米铁个体呈球形，呈分散状负载于膨润土；（2)相同铁含量的B-NZVI处理 Cr(VI)的效率远大于纳米铁，还原反应符合伪一级反应动力学模型，表观速率常数K随着B-NZVI初始浓度的减小而减小；（3)B-NZVI在石英砂柱中基本无迁移，适用于点源污染，Cr(VI)穿透曲线为B-NZVI的实际应用提供了理论和实验基础。
关键调：膨润土；纳米铁；六价铬；批实验；柱实验
中图分类号：P595；X142
文献标志码：A
文章编号：10008527(2012)05093207
A Study on Bentonite-supported Nano Iron for Removal
ofCr（vI）inGroundwater
LI Chen-hua, CHEN Jia-wei
(Sechool of Earth Seciences and Resources, China Unitersity of Geosciences, Bejing100083, China)
Abstract : With the development of living standard and urbanization, groundwater pollution is becoming serious. It is hazardous to human health, ecotope and social security with the heavy metal and organic field pollutants. The issues of Cr( VI) contaminated groundwater are paid more attention on recently. As Cr( VI) has high toxici-ty and mobility in water compared to Cr( IIl ) , it is very important to deposit chromium by reduction of Cr( VI) into Cr( II ) using nano iron ; therefore, the contaminants in source region are stabilized and indiffused from all around. While the agglomeration and oxidation of nano iron is often unavoidable due to the very small particles, it is essential to study the disperse and stability of nano iron. In this paper, bentonite was used as a porous-based support material for synthesized nano iron. The results showed as follows. (1) Bentonite-supported nano iron particles are well sphere scattering on the bentonite. (2) The removal efficiency of B-NZVI is better than NZVI comparing the same iron content (1 g/L) B-NZVI, NZVI and 1 g/L bentonite. Reduction kinetics of Cr( V1) by B-NZVI were described by a pseudo first-order reaction. Kinetics studies of Cr( VI) reduction using B-NZVI suggested that the reactivity of NZVI particles supported on bentonite were decreased significantly with the decrease of initial iron content. (3) Column experiments showed that B-NZVI was no migratory in the column packed silicon dioxide and it indicated B-NZVI is suitably applied in point-source pollution. Breakthrough curve
收稿日期：20120420；改回日期：20120707；责任编辑：或开静。
基金项目：中国地质调查局项目（1212011120288）；中央高校基本科研业务费专项资金项目（2012123，2010ZD14）：国家科技重
00000
作者简介：李晨择，女，硕土研究生，1990年出生，总质工程专业，主要从事应用地球化学方面的研究。
Email; lcheugb@ 163. com。
通信作者：陈家玮，男，教投，博士，1974年出生，地球化学专业，主要从事地球化学研究和教学工作。
Email; chenjiawei@ cugh. edu. en。