The mechanism of ligand-exchange sorption of aromatic amines such as p-chloroaniline, p-toluidine, and p-nitroaniline as ligands on a Co2+-loaded ligand exchanger has been studied. The observed rate seems to be related to the rate of ligand sorption with the mobile phase and pH in the aqueous phase. The saturation capacity and binding constant of ligand sorption on the resin increase with increasing basicity of amines. The rate of attainment of equilibrium sorption of aromatic amines is seen to be nearly similar. Coupled with the fact that different concentrations of solution were employed, these results may be interpreted as indicating that particle diffusion is the rate-controlling step. On the contrary, film diffusion was not rate-controlling step in the ligand sorption process under the conditions employed. It is shown that the kinetic parameters measured in single component experiments provide good prediction behavior. The pH dependencies and sorption isotherms of aromatic amines on the resins were also studied.