Calculation of the Henry constant for the adsorption of unsaturated and cyclic hydrocarbons on a uniform plane surface

A method previously proposed for describing the adsorption of nonpolar molecules on uniform adsorbents was used for a priori calculation of adsorption characteristics for a broad spectrum of molecules including cyclic and unsaturated hydrocarbons. Relationships of the adsorption parameters with molecular structure and with three main characteristics of a uniform adsorbent (the van der Waals size of surface atoms and the energies of interaction of sigma and pi electrons with the surface) were established. These relationships allow calculating the adsorption energy and the Henry constant over a wide temperature range to a high accuracy. Theoretical temperature dependences of Henry constants for a number of polycyclic and unsaturated hydrocarbons were compared to experimental data.