Concurrent removal of cadmium and benzene from aqueous solution by powdered activated carbon impregnated alginate beads

Abstract

Applicability of a powdered activated carbon impregnated alginate beads (ABPAC) was examined toward simultaneous removal of heavy metal (cadmium) and volatile organic compound (benzene) from water. Sorption of cadmium and benzene by ABPAC was investigated in both single and binary systems as a function of contact time (1h–11d), initial pH (4–7), and initial concentration of cadmium and benzene (10–600mgL–1). The sorption capacity of APBAC for cadmium and benzene was 149.32 and 89.60mgg–1, respectively. Sorption kinetics was well described by the pseudo-second-order model with correlation coefficients, R2>0.994. Cadmium sorption capacity increased from 41.76 to 56.09mgg–1 with increasing pH from 4 to 7, while benzene sorption was not much influenced. The Langmuir model best correlated with adsorption of cadmium and benzene on ABPAC. Our results indicated no competition effects in a binary-contaminant system, which proves the practical utility of ABPAC for the concurrent sorptive removal of aqueous phase heavy metals and volatile organic compounds.