Consequences of assuming a maxwellian energy distribution for adsorption sites

Abstract

A general adsorption isotherm has been previously proposed by us and applied to zeolites and metals. The isotherm is based on a Maxwell–Boltzmann distribution function for the energy of the adsorption sites and on the Langmuir isotherm for each set of homotactic sites. The general isotherm is explored further, and is applied to the adsorption of noble gases on metal films in ultra-high vacuum conditions. The general picture of adsorption on metals and on zeolites as it emerges from such considerations is discussed and the predicted behaviour of the differential heats of adsorption is compared to the predictions of the Dubinin Radushkevich isotherm.