膨润土、高岭石对锌的吸附和解吸

THE CHARACTERISTICS OF ADSORPTION AND DESORPTION OF ZINC BY BENTONITE AND KAOLINITE

本文研究了膨润土和高岭石对Zn^(2+)的吸附和解吸。结果表明,所得到的吸附Zn^(2+)量的资料适合Freudlich和Langmuir方程,与CEC(阳离子交换量)呈正相关,Mg质粘土矿物略高于Ca质。这是由于阳离子水化度不同所致。从Ca质的膨润土和高岭石解吸Zn^(2+)状况看,粘粒表面解吸下来的Zn^(2+)数量与其吸附量呈正相关。经连续解吸后,高岭石粘粒表面吸持的Zn^(2+)量占解吸量的百分数高于膨润土。表明高岭石与Zn^(2+)亲和力高于膨润土。

This paper centres on the characteristics of adsorption and desorption of zinc on kaolinite and bentonite. The data on zinc adsorption obtained from the present study fit with Freundlich and Langmuir equations. The amounts of zinc adsorbed are directly proportional to the eation exehange capacity of these minerals. The amounts of zinc adsorbed on Mg-bentonite and Mg-kaolinite are higher than those on these minerals saturated with calcium, depending on hydration. The amounts of zinc desorbed from Ca-bentonite and Ca-kaolinite increase with those of zinc adsorbed. Zinc is bound with kaolinite more tightly than with bentonite.