A mathematical method for determination of absolute adsorption from experimental isotherms of supercritical gases

A mathematical method was proposed for the determination of absolute adsorp tion from experimental isotherms. The method is based on the numerical equa lity of the absolute and the excess adsorption when either the gas phase de nsity or the amount adsorbed is not quite considerable. The initial part of the experimental isotherms, which represents the absolute adsorption, beca me linear with some mathematical manipulations, The linear isotherms were r eliably formulated. As consequence, either the volume or the density of the supercritical adsorbate could be determined by a non-empirical way. This m ethod was illustrated by the adsorption data of supercritical hydrogen and methane on a superactivated carbon in large ranges of temperature and press ure.