镉在蒙脱石等粘土矿物上的吸附行为研究  

The adsorption behaviors of montmorillonite and some other clay minerals for cadmium

作　　者：朱霞萍[1] 白德奎[1] 李锡坤[2] 曾江萍[1] 曹三勇[1] 

机构地区：[1]成都理工大学材料与化学与化工学院,四川成都610059 [2]广东省物料实验检测中心,广东广州510080

出　　处：《岩石矿物学杂志》2009年第6期643-648,共6页Acta Petrologica et Mineralogica

基　　金：广东省地调项目(1212010511216-04-02-01);成都理工大学校研究基金(2006YG05)

摘　　要：研究了土壤中主要硅酸盐粘土矿物蒙脱石、伊利石、高岭石、海泡石对重金属镉的吸附行为。结果表明:硅酸盐粘土矿物吸附镉受酸度和离子强度的影响;吸附反应是快反应,能很好地符合Lagergren二级吸附速度方程;优化条件下的高岭石对镉吸附很弱,蒙脱石、伊利石、海泡石对镉的实验饱和吸附容量分别为2.88、1.08、2.82mg/g,蒙脱石吸附镉更适合Freundlich拟合,伊利石、海泡石对镉的吸附结果更适合Langmuir拟合;相关性分析表明,硅酸盐粘土矿物对镉的饱和吸附容量大小与其理化性质有关,其中矿物中氧化锰含量高低与其对镉饱和吸附容量大小的相关性达到极显著水平。An experimental study of the adsorption of clay minerals such as montmorillonite,illite,kaolinite and sepiolite for Cd2＋ was conducted. The results indicate that acidity and ion intensity are factors affecting adsorption,that the adsorption reaction is rapid,and that adsorption kinetics is fitted well with the Lagergren quasi-second reaction rate model. Under the optional conditions,the adsorption of kaolinite for cadmium is weak,and the saturated adsorption capacities of montmorillonite,illite and sepiolite for cadmium are 2.88,1.08 and 2.82 mg/g respectively. The behaviors of adsorption of Cd2＋ on montmorillonite are fitted to Freundlich Model,while the behaviors of adsorption of Cd2＋ on illite and sepiolite are fitted to Langmuir Model. Correlation analysis shows that the saturated adsorption capacity of cadmium on silicate clay minerals is related to its physical and chemical properties,and the correlation between manganese oxides and the saturated adsorption capacity of cadmium is extremely significant.

关 键 词：粘土矿物 镉 吸附 

分 类 号：P579[天文地球—矿物学]