• 论文 •

### 粒度不均一交换剂的离子交换反应动力学(Ⅰ)——粒内扩散或液膜扩散控制反应速度的同位素交换反应

1. 兰州大学现代物理系
• 收稿日期:1980-07-04 出版日期:1982-04-24 发布日期:1982-04-24

### KINETICS OF ION EXCHANGE IN POLYDISPERSE SYSTEMS (I)——RATE LAWS FOR PARTICLE-DIFFUSION OR FIRM-DIFFUSION CONTROLLING ISOTOPIC EXCHANGE

Xing Zheng, Tao Zuyi

1. Department of Modern Physics, Lanzhou University, Lanzhou
• Received:1980-07-04 Online:1982-04-24 Published:1982-04-24

Abstract: In the earlier theoretical treatment, it is usually assumed that all beads of ion-exchanger are spherical and uniform in size.So far the rigorous treatment of isotopic exchange reaction with nonuniform spherical particles has not been given. In this paper, the kinetics of isotopic exchange reaction in systems simultaneously involving ion-exchanger particles of different radii is investigated.The theoretical expressions of polydisperse systems for particle-diffusion control or film-diffusion control have been deduced to predict the fraction of heterogeneous isotopic exchange between ion-exchangers and ions in a solution of finite volume. These expressions have been calculated by computer. It is shown that the smaller particles, reacting more rapidly all the time, will overshoot their eventual equilibrium value and, therefore, they have to release, after some time, a considerable amount of these isotopes already absorbed in favor of the slower reacting particles. Some other conclusions have also been drawn.