MOLECULAR ADSORPTION ON SILICA-GEL SURFACE FROM LIQUID-MIXTURES

Adsorption isotherms from ternary liquid mixtures (polar component + b inary solvent) on silica gel have been determined at 298 K. The analys is of the changes of a binary solvent composition during adsorption of a polar component enables determining if the surface phase contains t he molecules of polar component only or if there exists the possibilit y of the formation of the mixed surface phase. Monolayer capacities ha ve been determined for investigated systems. Taking into account appro priate cross-sectional areas of adsorbate molecules, the specific surf ace area of the silica gel has been calculated on the basis of liquid adsorption data. Obtained specific surface areas for different adsorba tes were compared with BET values from nitrogen adsorption data.