Removal of Lead and Cobalt from Pharmaceutical Effluent: Efficiency of Activated Coconut Shell and Commercial Activated Carbon

Zinc Chloride, Sodium Sulphate and Boric acid were used as activating agents for coconut shell. The activated carbons prepared from the mentioned activating agents labelled AC1, AC2, and AC3 were tested for their adsorptive capacities compared with commercially activated carbon (CAC) made from wood, a product of Calgon for their removal of lead and cobalt from pharmaceutical effluent. The percentage removal of Cobalt and lead onto activated carbons from coconut shell was investigated in a batch system by considering the effects of contact time and pH. Adsorption processes in the study indicate that the sorption of lead and cobalt with AC1, AC2 and AC3 were higher than with CAC. Contact times of 60 and 90 min were found to be the optimum for Cobalt and lead respectively. The adsorption kinetic data were analysed with pseudo first-order, pseudo second-order, Natarajan and Khalaf first-order and Elovich models. The results indicated that the second order model best described the adsorption kinetic data. The proximity of generated data to those reviewed in literatures is an indication that activated carbons from coconut shell have the potential for the adsorption of cobalt and lead from pharmaceutical effluent.