Abstract: The Nernst-Planck equations were applied to the study of the ion exchange reaction kinetics for the transition metal ions(Co²⁺, Cu²⁺, Zn²⁺and Cd²⁺) with H+-ions on stannic antimonylpy-rophosphate(SSbPP). Under the control of particle diffusion, the rate of exchange has been found to be independent of the metal ion concentration at and above 0. 050 mol/L. The self-diffusion coefficients (D₀), the activation energies(E_a) and the entropies of activation (△S^*) of transition metal ions have also been calculated by solving Nernst-Planck equations with Apple-II computer. These parameters are useful for predicting the ion exchange mechanism taking place on SSbPP.

Key words: Inorganic ion exchanger, Stannic Antimonylpyrophosphate, Transition metal ions, Kinetics of ion exchange reaction