MICROPORE STRUCTURE OF ACTIVATED CARBONS PREPARED FROM A SPANISH SUBBITUMINOUS COAL STUDIED BY CO2, BENZENE, AND CYCLOHEXANE ADSORPTION

Two series of activated carbons with different degrees of activation w ere prepared from a Spanish subbituminous coal by pyrolysis and steam activation. The micropore structure of the activated carbons so obtain ed was characterized by CO2 adsorption at 273 K by applying the Dubini n-Astakhov equation and by benzene and cyclohexane adsorption at 303 K by applying the Dubinin-Stoeckli equation corrected with the Dubinin- Zaverina equation, This last method has allowed discovery of the real micropore volume and its distribution and dispersion, as well as the m esopore surface area of the activated carbons. Results obtained also s how that the Dubinin-Astakhov equation applied to CO2 adsorption isoth erms on activated carbons with a medium to high degree of activation i s affected by the adsorption on the mesopore surface.