Experimental Studies of the Generalized Adsorption Isotherm for the Supercritical Region

摘要

Some problems arise with the characteristic curve proposed by the Dubinin-Polanyi potential theory when this is applied to supercritical adsorption although, as an alternative, the generalized isotherm is capable of well modelling isotherms for different temperatures. In this paper, the general applicability of the generalized isotherm is demonstrated by the experimental adsorption data for N_2 and CH_4 on activated carbon and silica gel. It has been shown that although the prerequisite of an energetically uniform surface is not essential, the surface concentration is limited to a range beyond which the general isotherm cannot be constructed.