镉在土壤中吸持等温线及模拟研究

研究了重金属镉在黄绵土、黑垆土、土娄土、黄褐土、黄棕壤、黄壤和渭河砂土上的吸附特征。结果表明 ,供试土壤镉吸持能力为石灰性土壤 >砂土 >酸性土壤 ,黄棕壤显著大于黄壤。在试验浓度范围内 ,镉在土壤中吸持的最佳模型为 Henry模型。黄壤 Cd2 +吸持过程为放热反应 ,黄棕壤的热效应不明显 ,其余土壤为吸热反应 ;p H对 Cd2 +吸持有显著影响 ,是这 3类土壤吸持 Cd2 +能力产生差异的主导因素 ;粘粒对镉吸持也有一定的影响

Soil cadmium retention isotherms and simulation research

The ability of cadmium retention in the test soils are as follows:calcareous soil >sand soil>acid soil.The yellow brown soil is much bigger than that of yellow soil.In the range of concentration of experiment,the optimal model of cadmium retention in the soils is Henry model.The result of the experiments express that the processes of cadmium retention of yellow soil is exothermic,and of yellow brown soil has little heating effect,and of the other soils are endothermic reactions.The soil pH and clay content have significant effects on cadmium retention reaction,and the soil pH is the dominant factor of the three kinds of soils influencing the soil cadmium retention ability.