离子交换平衡及动力学的研究——Ⅳ.Ca^(2+)-H^+阳离子交换平衡及动力学  

Studies on Ion Exchange Equilibria and Kinetics Ⅳ.Ca2+-H+ Cation Exchange Equilibrium and Kinetics

作　　者：刘怀振 杨彦文 陈星蕖[1] 陶祖贻[1] 

机构地区：[1]兰州大学现代物理系,兰州730000

出　　处：《离子交换与吸附》1992年第6期485-489,共5页Ion Exchange and Adsorption

基　　金：国家自然科学基金

摘　　要：用强酸性阳离子交换树脂001×7研究了Ca^(2+)-H^+阳离子交换反应的平衡及动力学,测得该反应的等温线及选择系数,求得修正选择系数、合理热力学平衡常数(K_α=18)以及交换剂相中各组分的合理活度系数。实验发现,该反应的正、逆交换的机理不同。结合以前研究过的Na^+-H^+、UO_2^(2+)-H^+及Y^(3+)-H^+反应的正、逆交换的机理,探讨了造成正、逆交换机理不同的原因。本文还估算了液膜互扩散系数与液膜厚度之比,求得了随交换剂相组成变化的积分粒内互扩散系数。The kinetics of ion exchange of two different counter ions on the strong acid cation exchange resin depends on the selectivety of the resin for them as well as the difference in their ionic mobility. In the previous literature, influence of selectivity of strong acid cation exchange resin on the ion exchange reaction mechanism is less noted, especially its effect on the forward and reverse exchange mechanisms is neglected. In this paper,the equilibrium and kinetics of cation exchange 2HR+Ca2+=CaR2+2H+ with 001×7 strong acid cation resin has been studied. The isotherm for this exchange reaction has been determined, and the rational equilibrium constant Ka calculted,Ka=18. The difference in exchange mechanisms of forward and reverse reactions,HR/Ca2+ and CaR2/H+,has been found,and this difference also found for the forward and reverse exchanges,HR/UO22+ and UO2R2/H+,HR/Y3+ and YR3/H+ in our previous papers. This difference attributes to the great preference of resin for metal ion over hydrogen.

关 键 词：离子交换 平衡 钙离子 氢离子 

分 类 号：O647.316.1[理学—物理化学]