Certain aspects of heterophase ion exchange

Ion exchange between an aqueous solution of KCl and a solution of tetraoctylammonium bromide in toluene has been studied at 20–70°C. Equilibrium exchange constants were measured. The free energy of the ion exchange is determined to a large extent by Coulombic interaction, which increases with decrease in the radius of the ion. The strength of the Q⁺X^– bond is weakened on passing from the normal onium salt to the hydrate and the rate of ion exchange increases. The position of equilibrium during approach to it from different sides may be affected by different formation processes of complexes with low activity in respect to exchange.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1773–1776, August, 1991.