中文摘要：

采用1次平衡法，研究了不同pH值条件下重金属Cd^2＋的吸附特性。结果表明：在砂壤土中，相同pH值条件下，Cd^2＋的吸附量随体积分数的增加而增加，但各个阶段增加速度存在明显差别：初始体积分数为（0．1～1）×10^-6时，随着平衡体积分数的增加，吸附量变化较为缓慢；初始体积分数为（10～40）×10^-6时，吸附量随着体积分数的增加而迅速增加；当体积分数大于40×10^-6时，随着体积分数的增加，吸附量增长速度开始减慢。不同pH值条件下，随着pH值的升高，吸附量逐渐增加，当pH为3时，同等体积分数条件下吸附量最小，pH为11时，吸附量最大，在pH值从7变化为9时，变化最为明显。Freundich方程能较好的模拟不同pH值条件下的土壤对重金属Cd^2＋的吸附特性。

英文摘要：

The balance method was used to study the adsorption of Cd^2＋ under the condition of different pH level. The results show that. the adsorption capacity of Cd^2＋ increases with the concentration increasing under the condition of the same pH. There are obvious difference in different stages： the change of absorption capacity becomes slowly with the balance concentration increasing when the initial concentration is from 0.1 × 10^-6 to 1 × 10^-6 ; The absorption capacity increases rapidly with the balance concentration increasing when the initial concentration is from 10 × 10^-6 to 40 × 10^-6. When the inintial cencentration is more 40 × 10^-6 , the adsorption capacity increases become slowly with the balance concentration increasing. Under the condition of different pH, the adsorption capacity increases with the increase of pH. The absorption capacity is minimum when pH is 3, it is maximum when pH is 11 under the same concentration. The change become most obviously from pH 7 to 9. The Freundich function can well simulate the absorption of Cd^2＋ in sandy loam under the different pH.