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The theory underlying the adsorption behavior of carbon adsorbents is discussed as a basis f o r quantitat i v e analysis of t h e i r adsorption properties and microporow f i l l i n g of micropores f o r homogeneous and nonhomogeneous microporous s t r u c t u r e s are considered. Three principal parameters are proposed which describe the physical vapor adsorption end characterize the microporous structure.structure. The equations of the theory of volume As a r u l e carbonaceous adsorbents are microporous i n structure and cont a i n a r e l a t i v e l y small proportion of mesopores. The adsorption potentials of dispersion forces are enhanced i n micropores due t o the overlap of the f i e l d s from the opposite pore walls and interactions between the adsorbed molecules . Physical adsorption of vapors i n homogeneous micropores is described by the Theory of volume f i l l i n g of micropores (TVPM) ('Ref.1). The Dubinin-Raduehkevich (DR) equation is the principal formula of the theory w = woe-[ -( u p g O ) 2 ] (1 1 where A i s the d i f f e r e n t i a l molar work A = RTln(p,/p) (2) Using the small-angle X-ray scatering and adsorption techniquee (c& , 293 9) we have obtained f o r a slit-shaped model of carbon micropores CRef .2) where xo is the micropore half-width and Eo -c h a r a c t e r i s t i c adsorption energy. Stoeckli and Krachenbuehl developed a method f o r determining the magnitude 2x0 involving calorimetric measurements of the heats of immersion Into liquids w i t h d i f f e r e n t molecular s i z e (Ref .3) . McEnaney has summarized a l l the results and obtained k = 12.0 2 1 . 4 kJ.nm/mol (Ref.4). Considering (1) and (3) the DR equation becomes (4) x0 = WEo (3 1 (4) w = w R , e x p [ -m x ,~ 2 2 3 where m = ( 1 /~3 k )~ ia a coefficient f o r a given vapor. According t o eqn. 0) the constancy of Eo meam that the micropore s i z e xo 5s 1841

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