Gas Chromatographic Study of Specific Physisorption by Activated Carbons

Abstract
Gas chromatography has been used to study the adsorption of C2–C6 n-alkenes and methanol by activated carbons. Although the higher alkenes adsorb non-specifically only, ethene can also undergo specific interactions with hydroxyl surface sites. The adsorption of alcohols is effected by both adsorbate–adsorbent and adsorbate–adsorbate interactions to such an extent that only in the case of methanol is it possible to obtain reliable chromatographic results. Methanol can undergo specific interactions with both hydroxyl and carbonyl surface sites. The use of methanol and ethene in combination can be used to follow changes in surface polarity brought about by surface modification procedures.