| Abstract: | An inverse selectivity was found for the adsorption of alkali metal cations on the side walls of montmorillonite and kaolinite crystals. The results are in accord with the data for the adsorption of alkali metal cations on silica gel at neutral and high pH and on alumina and hematite at pH values above their isoelectric points. The existence of a direct or inverse selectivity series for these cations depends on the concentration of exchange sites on the surface of mineral ion exchange materials and the contribution of the energy of the electrostatic repulsion between adjacent cations to the total energy of their adsorption on the ion exchange materials. A. V. Dumanskii Institute of Colloid Chemistry and Water Chemistry, National Academy of Sciences of Ukraine, 42 Akademika Vernadskogo Prosp., Kiev-142, Ukraine 252680. Translated from Teoreticheskaya i éksperimental’naya Khimiya, Vol. 34, No. 1, pp. 32–35, January–February, 1998. |
