The free and total energies of interaction of coals with methyl alcohol

Abstract

It is possible, in principle, to calculate the heat of immersion of a solid in a liquid from adsorption data. Thus, for reversible adsorption of an insoluble vapour, the free-energy lowering AG of the adsorbent is given by the integrated form of the Gibbs-Duhem equation,where PI, p 2 are the initial and final pressures of the vapour, m is the quantity in grams of vapour adsorbed at a pressure p (or fugacity f), and M is the molecular weight of the adsorbate. This equation holds whatever the mechanism of interaction : e.g. whether the adsorbed phase Bangham, Nature, 1944, 154, 837.