SORPTION CHARACTERISTICS OF AGRO WASTE PRODUCT IN THE REMOVAL OF LEAD (II)

Abstract

The influence of particle size, contact time, initial concentration of the adsorbent, adsorbent dose, pH, cation, anions and co-ions, and temperature on the adsorption capacity of sawdust to remove Pb(II) from aqueous systems was determined. The adsorption of Pb(II) over sawdust revealed maximum capacity for the sorbents with the smallest particle size. The mimimum contact time required to attain equilibrium for the system was 20 minutes at an initial concentration of 10 mg/litre. The sorptive behaviour was observed to improve under the conditions of pH 5. The adsorption of the metal ion was significantly inhibited by the presence of cations, anions and co-ions. The adsorption dynamics and equilibrium factors were confirmed with the use of the Fruendlich, Langmuir and Tempkin isotherm models. Sawdust was found to be effective with higher chelating ability in the removal of Pb(II).