Ponkan peel: A potential biosorbent for removal of Pb(II) ions from aqueous solution

The ability of ponkan peel, a natural biosorbent, to remove Pb(II) ions from aqueous solution by adsorption was studied. The experiments were carried out by batch method at 25 °C. Important parameters such as pH, initial Pb(II) concentration and contact time on the biosorption were investigated. The optimal pH value for adsorption capacity was 5.0. The biosorption was relatively quick, about 60 min. Based on the Langmuir-type isotherms the maximum uptake capacity of lead ions on ponkan peel was 112.1 mg g−1. The result shows that ponkan peel is a good biosorbent for removing lead ions from aqueous solution and does not need any chemical or physical pre-treatment. The ponkan peel biosorbent is a low cost material that shows potential to be applied in wastewater technology for remediation of toxic metal.