不同土壤粘粒对Cu^(2+)和Pb^(2+)的等温吸附特征研究

Isothermal Adsorption Characteristics of Different Soil Clay to Cu^(2+) and Pb^(2+)

以取自孝感市孝南区的水稻土、武汉市黄陂区的林地土壤、武汉市东西湖区的黄瓜菜地土壤、武汉理工大学的荒地土壤为对象,研究了4种不同类型土壤粘粒对Cu2+、Pb2+的等温吸附特征及初始pH值对重金属吸附的影响。结果表明:4种土壤粘粒对Cu2+的吸附均可用Frendlich、Langmuir方程进行拟合,但用Frendlich方程拟合效果相对较好;相同初始浓度情况下,4种土壤粘粒对Pb2+的吸附量约为对Cu2+的吸附量的5倍;在所研究的pH值范围内,4种土壤粘粒对Cu2+的吸附量随pH值的升高变化不大,但对Pb2+的吸附量随pH值的升高而增大。

To study the isothermal adsorption characteristics of four different types of soil clay to Cu2+, Pb2+ and influences of initial pH on adsorption of heavy metals, the paddy soil from south Xiaogan city, the forest soil from Huangpi district of Wuhan city, the cucumber garden soil from Dongxihu district of Wuhan city and the wasteland soil from Wuhan University of Technology were taken as materials. The Langmuir equation and Frendlich equation were developed for adsorption characteristics of the four types of soil clay to Cu2+ and Pb2+, and the results ind icated that adsorption was characterized better in Frendlich equation; the adsorption amount of all the types of soil clay to Pb2+ was about five times as to Cu2+ with the same initial concentration; as pH rised, the changes of adsorption amount of all the types of soil clay to Cu2+ were not obvious but increased to Pb2+.