The removal of heavy metals from aqueous solutions by sawdust adsorption -removal of lead and comparison of its adsorption with copper

In this work sorption of lead on sawdust (SD) has been studied by using bat ch techniques. Similar to the sorption of copper, the equilibrium sorption levels for lead is a function of the solution pH, contact time, sorbent and sorbate concentration. The equilibrium adsorption capacity of sawdust for lead was measured and extrapolated using Linear Freundlich and Langmuir iso therms and compared with that for copper. Metal ions which are bounded to t he sawdust could be stripped by acidic solution so that the sawdust can be recycled. Non-equilibrium experiments were done by using glass columns. The results indicate the potentially practical value of this method in industr ies and also provide strong evidence to support the adsorption mechanism pr oposed. Even though the focus of this work is on lead, some results from pr evious study for copper have been incorporated here for sake of comparison. (C) 2001 Published by Elsevier Science B.V. All rights reserved.