Performance of low-cost adsorbents for the removal of copper and lead

Bagasse and fly-ash are waste materials and have been used for the removal of copper and lead from aqueous solutions. Investigations were carried out using a batch sorption process. The efficiency of sorption of copper and lead is affected by aqueous solution pH, contact time, adsorbent dose, type and size of adsorbents and initial metal ion concentration; all of which factors were investigated. Results of the investigations were used in kinetic studies to understand the mechanism of the adsorption process. The adsorption equilibrium is well correlated by the Langmuir, Freundlich and Bhattacharya & Venkobachar models. The adsorption capacity follows the sequence of fly-ash>bagasse>PAC for Cu(II) removal, and PAC>bagasse>fly-ash for Pb(II) removal, in optimum conditions.