Adsorption of zinc, cadmium and mercury ions from aqueous solutions on an activated carbon cloth

The adsorption of zinc, cadmium and mercury ions from aqueous solutions on an activated carbon cloth was studied as a function of their concentrations and solution pH. For that purpose, pertinent adsorption isotherm data was collected at different pH values. The amount of adsorbed zinc and cadmium ions increases while the amount of adsorbed mercury remains constant with an increase in the equilibrium pH of the solution. The adsorption mechanisms of metal ions on activated carbon cloth are discussed, Under the conditions investigated, these primarily involve adsorption of monovalent cations (Zn and Cd) or precipitation of metal hydroxides (Cd and Hg) on the activated carbon cloth tested. (C) 2002 Elsevier Science Ltd. All rights reserved.