Preparation and characterization of powdered and granular activated carbon from Palmae biomass for cadmium removal

Abstract

This paper investigated the characteristics of powdered activated carbon (PAC) and granular activated carbon (GAC) derived from African Palmae shell and its application in the removal of cadmium(II) ions in aqueous media. The African Palmae shell is obtained from a widely and easily grown palm tree found in the African tropics. This biomass has not been adequately studied as a precursor in the production of activated carbon. Palmae shell has been processed into powdered and activated carbon and tested for its efficiency in removing cadmium(II) (Cd(II)) ions. The characterization includes determination of proximate analysis, ultimate analysis, point of zero charges, and surface area. The reaction mechanism and kinetics were predicated on the proton coefficient that was < 1 for both PAC and GAC, some mass transfer rates, and intraparticle diffusion. The values for these characteristics revealed that protonation was not actively involved in the adsorption process. The reaction also was not a rate-limiting process. The parametric batch mode studies of contact time (maximizing at 93.2% for PAC and 83.5% for GAC), initial Cd(II) concentration, pH (93% for PAC and 88% for GAC), and dosage of activated carbon indicated that PAC readily removes Cd(II) than GAC. Both PAC and GAC derived from Palmae shell are, therefore, novel biosorbents.