On the formation of supramolecular systems in the adsorption of aromatic compounds at porous adsorbents

Competitive adsorption of anisole, benzaldehyde, benzoic acid, benzene, toluene, and phenol from dilute solutions in n-heptane at three chemically different porous adsorbents was studied by high-performance liquid chromatography (HPLC). The retention times of these compounds were used to calculate the equilibrium constants of the adsorption isotherms, the partition coefficients, and the Gibbs energy changes. The results obtained made it possible to estimate the Gibbs energy changes in the competitive adsorption of arenes leading to the formation of supramolecular surface compounds at cellulose and silica and the formation of arene clusters at the pyrocarbon surface from dilute solutions in n-heptane.