【摘要】 采用间歇法研究了镉在不同土壤中吸持的动力学特征 .镉在土壤中的吸持分为快速反应和慢速反应两个阶段 ,其中快速吸持阶段以化学吸持为主 ,而慢速吸持以物理吸附为主 ;在低温下 (2 93K) ,镉吸持速率与时间符合方程lnV =A +Bt ,高温下 (313K)为V =A+Blnt;不同类型土壤镉吸持的动力学模型以双常数模型较优 .更多还原

【Abstract】 Kinetic characteristics of cadmium retention by different soils were studied using the batch techniques. Cadmium is adsorbed by the soils at different rates. According to the rate, the reaction of retention can be divided into two types: fast and slow. For the fast reaction, the chemical adsorption is the main adsorption, for the slow one, the physical adsorption is the main adsorption. At low temperature (293K), cadmium retention rate and the time accord with the model ln V=A+Bt, at high temperature (313K), V=A+B ln t model is the best one. For the different soils, the optimum model of cadmium retention is the two constants model.更多还原