DESCRIPTION OF SORPTION EQUILIBRIA FOR IONS ONTO ACTIVATED CARBON USING THE SURFACE COMPLEXATION THEORY

The surface of activated carbon contains a large variety of ionizable groups which lead to the sorption of either anions and/or cations from the aqueous phase. The amphoteric sorption of simple inorganic specie s has been described by means of the theory of surface complexation. E ach kind of species is assumed to be arranged in an ordered Stern laye r parallel to the surface. For the sorption of each kind of ion a set of two characteristic equilibrium parameters can be evaluated from equ ilibrium data. Evaluation is possible both from simple or from multico mponent systems. The parameters remain unchanged also in systems with additional ions. Evaluation of data for two commercially available car bons reveals a very satisfactory prediction of the carbon loading. (C) 1997 IAWQ. Published by Elsevier Science Ltd.