Kinetics of Adsorption from Single and Binary Solutions on Activated Carbons with Chemically Different Surfaces

Abstract

The effective surface diffusion coefficient DS for model adsorption systems was determined experimentally in a mixer tank with a constant solution volume. As an adsorbent, modified activated carbons with chemically different surfaces were used. The adsorbates were single and binary aqueous solutions of 10 phenolic compounds. The effect of the physicochemical parameters characteristic for the adsorption system (pure energy of adsorption, dipole moment, molar reaction, parachor, solubility, molecular diffusion coefficient in water) on changes in the DS values was analyzed. It was observed that the extent to which DS decreased for adsorption from binary solutions relative to single solutions depended on the adsorbent–adsorbate interactions and the content of oxygen on the activated carbon surfaces.