Application of a New Thermal Model for the Determination of London Dispersive Properties of H-β-Zeolite/Rhodium Catalysts Using New 2D Chromatographic Models.

A new methodology based on the Hamieh thermal model was applied for the determination of the surface properties of solid surfaces. The new approach consisted of the accurate quantification of the London dispersive surface energy of materials using the two-dimensional inverse gas chromatography technique at infinite dilution. This technique used the notion of the net retention volume of adsorbed molecules on the solid catalysts, allowing the determination of the free energy of adsorption. The Hamieh thermal model proving the temperature effect on the surface area of organic molecules adsorbed on H-β-zeolite/rhodium catalysts at different rhodium percentages was used to determine the accurate values of the London dispersive surface energy of solid surfaces at different temperatures. This new method also allowed a precise evaluation of the dispersive adhesion work, dispersive surface enthalpy, and entropy of adsorption of n-alkanes adsorbed on the catalysts. In this paper, the London dispersive surface energy and adhesion work of H-β-zeolite-supported rhodium catalysts were determined using the free energy of adsorbed molecules obtained from the two-dimensional inverse gas chromatography technique at infinite dilution. It was proved that the London dispersive surface energy strongly depended on the temperature and the rhodium percentage, while the dispersive adhesion work of n-alkanes adsorbed on H-β-zeolite/rhodium catalysts was proved to be a function of the temperature, rhodium percentage, and the carbon atom number of the n-alkanes.