Equilibrium, Isotherm and Kinetics Studies for the Uptake of Lead Ions from Aqueous Solution Using Rice Husk

Abstract- Industrial and domestic effluents, as well as indiscriminate applications of various chemicals, pesticides etc. have contributed to the deterioration of environmental quality. Among these pollutants, heavy metals represent a special group because they are not chemically or biologically degraded in a natural manner. The adsorption process is being widely used by various researchers for the removal of heavy metals from waste streams and activated carbon has been frequently used as an adsorbent. Despite its extensive use in the water and wastewater treatment industries, activated carbon remains an expensive material. In recent years, the need for safe and economical methods for the elimination of heavy metals from contaminated waters has necessitated research interest towards the production of low cost alternatives to commercially available activated carbon. The adsorption of Pb (II) metal ions on rice husk has been found to be pH, contact time, adsorbent dose and initial metal ion concentration dependent with the maximum removal efficiency of 80%. The adsorption parameters were determined using Langmuir and Freundlich isotherm models. Also, the adsorption kinetics was studied using pseudo first order and second order model showing that the adsorption process follows the second order kinetics.