Henry coefficients of adsorption predicted from solid Hamaker constants

A new model is proposed to a priori predict single component adsorption equ ilibria of different gases and vapours on activated carbons and graphite/gr aphitized carbon black. Emphasis is laid on the Henry region, where the int eraction energy between adsorbate molecules and the adsorbent determines ad sorption characteristics. II is shown that Henry coefficients can be predic ted on the basis of the three-dimensional van-der-Waals equation for gases and the Hamaker constant of solid, which is different for activated carbon or graphite/graphitized carbon black, respectively. The quality of predicti on is superior to the Steele/Lennard-Jones model in the case of graphite/gr aphitized carbon black, and yields a priori results for activated carbon wi thout any adjustment. (C) 2001 Elsevier Science Ltd. All rights reserved.