The potential theory of adsorption has been modified, taking into acco
unt the adsorbate compressibility. A new equation has been obtained fo
r adsorption isotherms in general cases. A particular case of micropor
ous adsorbents such as active carbons is considered in detail. The Dub
inin-Radushkevich equation has been corrected. The estimations, with t
he example of benzene adsorption on a model typical microporous adsorb
ent, show that ignoring the adsorbate compressibility leads to mistake
s in the calculation of adsorption isotherms via the conventional Dubi
nin-Radushkevich equation of about 10% at room temperature, and this d
ifference increases with an increase in the temperature. This paper is
a development of the previous paper (Commun. Acad. Sci. USSR (Chem.)
1, 13 (1992)), in which attention was paid mainly to calculating the m
icropore volume from the experimental value of the limit of adsorption
. (C) 1994 Academic Press, Inc.