Inverse Gas Chromatographic Study of the Factors Affecting Surface Diffusivity of Gases over Heterogeneous Solids

Abstract

In the present work, the various parameters affecting the variation of the surface diffusion coefficients, determined by the novel methodology of reversed‐flow gas chromatography (RF‐GC), for CO adsorption on a well‐studied Pt/SiO₂ catalyst, are under investigation. These are the adsorption energy, ?, the lateral interaction energy, β, the surface coverage, θ and the surface concentration of the adsorbate, c _s *. The magnitude of surface diffusion coefficient values, determined by RF‐GC, is comparable to those obtained by other experimental techniques, ascertaining the potential of the method. Physicochemical parameters giving information for the surface mobility, such as adsorption energies, local isotherms, local surface concentration of the adsorbate, and energy distribution functions can be determined in a single kinetic run.