This paper presents a theoretical analysis of experimental data for equilibrium sorption of CH/sub 4/ and CO/sub 2/ in fossil coals from a position of theory for volumetric micropore filling (TVMF) and ideas about coal as a loose polydispersed sorbent. Results of technical analysis for the test coals are presented. The analysis indicates that characteristic adsorption energy for methane on coal over the whole range of yield of volatile substances is greater than for CO/sub 2/ by a factor of 1.5-1.6. This indicates that with stable equilibrium conditions, sorption of CO/sub 2/ on coal is energetically more suitable than for CH/sub 4/.

On the basis of analysis of experimental data from equilibrium sorption of methane and carbon dioxide by natural coal, an expression for characteristic sorption energy is represented by equation of quasi-free state of sorbate molecules. Complex parameter formed by values obtained during analysis of sorption isotherms is a universal parameter linking energy and structural properties of various sorbents with different sorbates. Thermodynamic characteristics of sorbent are determined predominantly by inner structure of microsorptional area. Results of determination of sorption isotherm in coal from the Artema mine (Donbass area) at 303.2 K and coal from Zolotaya mine (Pervomaiskugol' association) within 0-70 C range using equations taken from previous report are given. 4 refs.