Effect of anaerobic biological activity on the adsorptive capacity of granular activated carbon

Abstract

The impact of anaerobic biological activity on the capacity of granular activated carbon (GAC) to adsorb organic compounds has not received much attention. In this study, the capacities of GAC for o‐cresol obtained from bottle‐point isotherm experiments were compared with the capacities measured in a completely mixed, biologically active, anaerobic GAC reactor treating a high‐strength synthetic wastewater containing acetic acid, phenol, and o‐cresol. O‐cresol was not biodegraded in the reactors and was removed solely by adsorption. Because of the low concentrations of phenol measured in the effluents from the reactors, no competition for adsorption between phenol and o‐cresol was observed. Also, the role of biological activity in the regeneration of GAC was demonstrated by preloading GAC with phenol and recovering the adsorbed phenol after the establishment of an active bacterial film on the GAC surface.