Removal of metal ions from aqueous solution by activated carbons obtained from different raw materials

Abstract

Abstract The adsorption of Pb 2+ , Cu 2+ , Zn 2+ and Cd 2+ from aqueous solution at 293 K by activated carbons obtained from different raw materials was studied. These carbons were prepared by water vapour pyrolysis of the raw materials—apricot stones, coconut shells and lignite coal. The influence of the solution pH on the adsorption processes has been studied. The presence of other metal ions in the solution decreases the adsorption of each of the ions. The selective adsorption of the metal ions is observed but the ones preferentially adsorbed do not completely prevent the adsorption of other ions. The chemical nature of the carbon surface and metal ions have great significance for the adsorption process.