Application of the Integral Equation Approach to the Study of Enthalpic Effects Accompanying Mixed-Gas Adsorption on Heterogeneous Solid Surfaces

Abstract

The possibilities of the Integral Equation approach for describing mixed-gas adsorption equilibria are presented. In this study, the energetic heterogeneity was described through the use of the Gaussian-like adsorption energy distribution function. As a result, very simple equations describing the isosteric heats of mixture components were obtained. The advantage of the model presented is the possibility of predicting the phase diagrams and enthalpic effects accompanying mixed-gas adsorption from a theoretical viewpoint based on pure-component adsorption data. New equations for isosteric heats of component mixtures were examined using the experimental data obtained by Dunne et al. (1996a, b, 1997), i.e. C2H6, CH4 adsorbed on silicalite and CO2, C2H6 adsorbed on NaX zeolite. The calculations are relatively simple and can be applied industrially.