镉在蒙脱石上的吸附解吸动力学与热力学研究  

Kinetics and Thermodynamics of Cadmium Adsorption and Desorption on Montmorillonite

作　　者：刘慧[1] 朱霞萍[1] 付小君[1] 刘文华 赵秋香 李锡坤 

机构地区：[1]成都理工大学材料与化学化工学院,四川省矿产资源化学高校重点试验室,四川成都610059 [2]广东省物料试验检测中心,广东广州510080

出　　处：《矿产综合利用》2013年第1期73-77,共5页Multipurpose Utilization of Mineral Resources

基　　金：广东省财政厅地质专项资助(2011208)

摘　　要：通过模拟自然环境特征,研究了不同温度下镉在蒙脱石上长时间的吸附和模拟酸雨对蒙脱石吸附镉的解吸动力学及热力学行为,结果表明:30、40、50℃时,蒙脱石对镉的吸附及模拟酸雨对镉的解吸均能很好地符合Lagergren二级动力学方程,相关系数R均在0.98以上;不同温度下的蒙脱石对镉的吸附量随时间的增加均呈上升-下降-平衡的趋势,酸雨对蒙脱石吸附镉的解吸量则随时间的增加表现为先上升后趋于平衡;蒙脱石对镉的吸附是一个自发的吸热过程,受温度影响较小,而模拟酸雨对镉的解吸过程与吸附过程相反,是一个非自发的放热过程,温度对它的影响较大。An experimental study of adsorption kinetics and thermodynamics for Cd2＋ on the montmorillonite and de- sorption kinetics and thermodynamics for Cd2＋ with simulated acid rain were conducted by simulating the natural en- vironment. The results indicated that the adsorption kinetics and desorption kinetics were fitted to the Lagergren quasi-second equation, the correlation coefficients（R） were larger than 0.98 when the temperatures were 30℃ ,40℃ and 50℃ respectively. The adsorption capacity of cadmium on montmorillonite exhibited a process of rise-fall-rise- balance with the time delay at different temperature, and desorption capacity were increased at first and then equi- librium with increase of time. Adsorption process of cadmium on montmorillonite was a spontaneous endothermic process ,and it was affected little by temperature. Desorption process was a non-spontaneous exothermic process ,and temperature had a big influence on it.

关 键 词：蒙脱石 镉 吸附 解吸 动力学 热力学 

分 类 号：TD926.5[矿业工程—选矿]