Effect of surface heterogeneity on adsorption on solid surfaces - Application of inverse gas chromatography in the studies of energetic heterogeneityof adsorbents

The paper presents a literature review of the chromatographic methods used for investigations of the heterogeneity of solid surfaces. Special attentio n is paid to inverse gas chromatography (IGC). Quantitative characteristics of heterogeneity of real solid surfaces including extreme models on adsorp tion centre topography of the "patch-wise" and "random" types are described . Analytical and numerical methods used for calculating the adsorption ener gy distribution function as a quantitative measure of surface heterogeneity are presented. Special attention is paid to the condensation approximation as well as to other approximations based on this assumption. IGC is presen ted as a quick precise and effective method to characterise physicochemical properties of different kinds of adsorbents. Advantages of IGC over tradit ional methods of gas and vapour adsorption are shown. (C) 2000 Elsevier Sci ence B.V. All rights reserved.