ENERGY-DISTRIBUTION FUNCTION-ASSOCIATED WITH DUBININ DESCRIPTION OF WATER-ADSORPTION ON ZEOLITE-Y

Different equations based on the Polanyi-Dubinin potential theory and applicable to the description of adsorption isotherms on zeolites are presented. Specifically, these equations are suitable for characterizi ng the adsorption potential distributions, the parameters of which are related to the energetic and structural heterogeneities of zeolites. The results presented show that the equation which takes into account both the surface and structural heterogeneities as well as the distrib ution of sizes of micropores participating in the process of adsorptio n is especially interesting. This equation represents the experimental adsorption data better than the other equations considered. Different heterogeneities of the samples of zeolite Y used in this study were a chieved by modification by ion exchange.