Water in homoionic and heteroionic mordenites: a calorimetric study. Part 1.—Alkali and alkaline earth metal forms

Abstract

Heats of immersion in liquid water of Na-Zeolon exchanged with alkali metal, alkaline earth, Ag⁺, Ti⁺ and Pb²⁺ ions are reported. The levels of ion exchange of Zeolon are shown to depend markedly on the degree of hydration of the cations. The heat data show that the Li⁺, Ca²⁺, Mg²⁺ and Sr²⁺ ions are located in the main channels after the immersion process and that the magnitude of the heats are governed by the energy of solvation of the cations by the anhydrous lattice. Correlations between the heats and cationic radii are shown to exist and these correlations could be useful for interpolation purposes.