ADSORPTION-ISOTHERMS FOR BIVALENT-CATIONS ON ION-EXCHANGE RESINS

Adsorption of the bivalent cations, manganese, cadmium and copper, on a strongly acidic cation exchange resin (R-Na form) followed the Freun dlich adsorption isotherm quite closely. On the basis of this fact, an empirical formula for such adsorption on iron exchange resins is prop osed. The proposed formula describes quantitatively the amounts of ion adsorbed on the resin as a function of the concentration of ion in qu estion, the concentration of coexistent salt and the pH of solution. A dsorption of bivalent cations onto a sodium form of cation exchange re sin was an endothermic reaction. The proposed formula also describes t he adsorption of copper on a chelating poly(4-vinylpyridine) resin.