含水量对电动修复铬污染高岭土的影响

Effect of Water Content on the Electrokinetic Remediation of Cr（Ⅵ） from Kaolin

土壤含水量对于污染土壤电动修复效率有着重要影响.实验选用受重铬酸钾作为污染物，高岭土作为污染土壤，研究了含水量对电动修复效率的影响.实验配制高岭土中Cr（Ⅵ）初始质量分数为500mg／kg，实验过程中施加电压20V，实验运行48h，用乙酸控制阴极pH在4-7之间。实验结果表明：高岭土的含水量在30％以下肘，由于电迁移和电渗流作用较小，去除效率很低，电能消耗教高}含水量超过50％，达到饱和含水量附近时，去除效率较高，含水量增加对其影响较小；含水量在30％-50％之间时，含水量对去除效率影响较为显著，随着含水量的增加去除效率呈线性升高。

This paper presents the effect of water content on electrokinetic remediation of the chromium polluted kaolin at laboratory scale. Potassium dichromate was chosen as the pollutant and its initial concentration was 500mg·kg^-1 kaolin. 20 DCV was applied, the experiments were operated 48h, and the pH of cathode was control at 4-7 with acetic acid. The results indicate that when water content was less than 30%, the process of electromigration and electroosmosis was not strong, the efficiency was very low, and the electric energy consumption was high. When water content was reach up to 50% i.e. saturated water content around, the removal efficiency was higher, and the effect of water content was insig-nificant. When the water content of kaolin is between 30% and 50%, the removal efficiencies increased linearly with the increase of water content.