Biosorption of Zinc from Wastewater by using Green Pea Pods

The removal of zinc (Zn(II)) ions from real and synthetic wastewater has been examined using an agro-waste, green pea (Pisum sativum) pod, as low-cost adsorbent material. The removal studies were done as a function of pH, contact time, biosorbent dosage and initial metal ion concentration. With increasing pH of the solutions, the adsorption of zinc by green pea pods was increased and adsorption capacity attained a maximum value at pH=8. With increasing the contact time, the amount of zinc adsorbed was increased and reached on equilibrium after 60 min. While, with increasing the amount of adsorbent to the solution, the adsorption of zinc was decreased and with increasing initial concentration of zinc ions, the removal efficiency was decreased but the metal uptake increased. Langmuir and Freundlich adsorption isotherm models were applied to determine the efficiency of pea pods used as an adsorbent. The linear regression analysis showed that the experimental data perfectly fit both models (Experimental data obtained were tested with the adsorption models like Langmuir and Freundlich isotherms).

Keywords:

Pea Pods , Adsorption , Metal Removal , Zinc , Isotherm