Remarks on the Adsorption of Alcohols from Ternary Solutions in Benzene and n-Heptane on Silica Gel

Abstract

Adsorption equilibria of binary and ternary solutions of alcohols in benzene and n-heptane on silica gel have been studied in order to clarify the mechanism of adsorption process of these compounds. The excess adsorption isotherms have been measured for hydrocarbon solutions of methanol, ethanol, butanol and pentanol. Interpretation of the experimental data was performed in terms of material balance relationships between bulk and surface phase. In the case of n-heptane solutions the multilayer surface structure is formed and the surface phase contains the alcohol molecules only. For benzene and ternary (alcohol + benzene + n-heptane) solutions the mixed character of the surface phase is observed. The composition of this phase is determined by competition of liquid components for the silica surface as well as its complexing tendency. Moreover, the extent of adsorption in methanol systems is connected with miscibility of liquid components.