Application of the shrinking core model to the kinetics of extraction of gold(I), silver(I) and nickel(II) cyanide complexes by novel anion exchange resins

This paper describes an investigation of the kinetics of loading of gold(I), silver(I), and nickel(II) cyanide complexes onto two novel anion exchange resins with high selectivity for the linear dicyanoaurate(I) and dicyanoargentate(I) complexes. The kinetic data fit well to a shrinking core theoretical model, and indicate that in all three complexes, the loading is controlled by the rate of diffusion of the ions penetrating the reacted layer. Diffusion coefficients were determined and those of Au(I) and Ag(I) cyano complexes are similar to one another but much higher (30 to 60 times) those of the Ni(II) cyano complex on these two resins.