中文摘要：

以模拟Cd污染土壤为供试土壤，使用阳离子交换膜，在电场强度为1 V·cm^-1的条件下研究了电动修复过程中土壤中不同位置pH值和Cd浓度的关系，建立了一套与阳极距离相关的线性模型。该模型表明，阳离子交换膜阻止阴极产生的0H^-进入土壤，阳极产生的H＋在土壤颗粒表面不断发生吸附-脱附过程并达到平衡，土壤各剖面pH值与该剖面和阳极的距离成反比。此外，在电动修复初期，土壤中Cd分布较为均匀，不同位置Cd去除速率与该位置和阳极的距离成反比。由修复实验的相关数据进行拟合得到的结果也很好地证实了这一点（r^2〉0．94）。有助于预测不同位置的电动修复效果，了解土壤中Cd的迁移过程及制约因素，为增强修复效果及改进电动修复技术提供理论依据。

英文摘要：

A distance-based linear model （DBLM） was developed to describe the relationship between soil pH values and the removal of total Cd across the tested soils as a function of distance from the anode during Electrokinetic Remediation （ER） with cation exchange membrane （CEM）. As OH^- generated at cathode could not pass through the CEM, an adsorption-desorption balance of H^＋ generated at anode was formed on the surface of soil particles. The model showed that pH values in the soil were inverse proportion to the distance from the anode. Besides, at the beginning of ER, Cd concentration and other chemical properties were almost the same all over the soil, and the removal velocity of total Cd was also in inverse proportion to the distance from the anode. To evaluate this model, an experiment using simulated Cd polluted soil was carried out, showing that this model could fit with the data very well （r^2〉0.94）. The model will help to predict the effect of ER on different soil profiles, also to learn Cd migration and factors limiting it.