Introduction into the characterisation of porous materials by inverse gas chromatography

Modern methods for the characterisation of porous materials are probably as numerous and divers as applications of porous solids. In recent years interest has grown in a deeper understanding of surface phenomena beyond the usual description of surface area and adsorption isotherm. This has lead to an introduction of more sophisticated approaches, which allow for a study of thermodynamic and kinetic information. One technique, which has been shown to be very valuable is inverse gas chromatography (IGC). Due to its increasing application in industry it is the intention of this short review to introduce the principals as well as the more common applications of IGC. The methods and parameters to be discussed include isotherm determination, the measurement of surface and free energy as well as the calculation of acid–base parameters. Further, the determination of the surface heterogeneity and heat of sorption is shown. The measurement and calculation of diffusion parameters is also briefly described. It is also the intention of this paper to discuss experimental aspects and common misconceptions.