Statistical Thermodynamics of the Sorption of Vapors by Solids

Abstract

The statistical method of treating the sorption of vapors, begun by Fowler and Guggenheim and extended to multilayer sorption by Cassie and Hill, is further generalized to include variable heats of sorption in different layers. It is shown under what conditions multilayer sorption can lead to a linear isotherm and to various modifications of the BET equation. The treatment is also extended to the case of interaction between sorbed molecules in the same layer.