The biosorption of lead ions from aqueous solution by Rhodococcus opacus bacteria was evaluated in this study. The effects of the solution's pH, biomass concentration, contact time and initial metal concentration were studied in batch experiments. The results of the kinetics studies revealed that the biosorption of lead on R. opacus cells followed pseudo-second order kinetics. The equilibrium data was analyzed using Freundlich and Langmuir models. The maximum uptake capacity (q max) obtained by the Langmuir adsorption model was 94.34 mg.g-1. In the competitive biosorption experiments, the lead removal was affected by the presence of other metal ions in the solution.
Lead; biosorption; bio-hydrometallurgy; Rhodococcus opacus
