Adsorption of Two Heavy Metal Ions on Dry Garlic Stem

This study reported the feasibility of adsorption of heavy metals using dry garlic stem, an environmentally-friendly and natural adsorbent．Using batch adsorption technique, the efficiency of the adsorbent was studied under different experimental conditions by varying parameters such as pH, initial concentration and contact time. The results show that at pH 2.03, adsorption temperature 35℃, the adsorption time 90 min and the amount of garlic stem 1.0 g, Pb²⁺ have the maximum adsorption capacity. The maximum adsorption capacity of the Pb²⁺ on garlic stem is 28.42 mg/g and the adsorption rate is 94.74%. At pH 4.05, the adsorption time 120 min and the amount of garlic stem 1.0, Cu²⁺ have the maximum adsorption at the same temperature. The maximum adsorption of the Cu²⁺ is 20.90 mg/g and the adsorption rate is 69.75%. The dry garlic stem was found to be efficient in removing lead and copper from aqueous solution as compared to other adsorbents already used for the removal of these ions.