Kinetic and Equilibrium Studies For the Removal of Chromium Using Eggshell Powder

Removal of toxic metals from wastewater occurs by either biological methods or physicochemical methods (e.g., adsorption, oxidation-reduction, chemical coagulation, ozone treatment, and membrane filtration). Low cost adsorbents have gained attention over decades as a means of achieving very high removal efficiency to meet discharge standards. The eggshell in a powdered form is a potentially useful material for the removal of toxic metal from industrial wastewater. It is suggested that the work is designed to increase the scale of egg shell application to cope with the removal of chromium under industrial conditions should be initiated. The principal component of the shell is calcium carbonate which comprises more than 90% of the carbon material. Powdered egg shell has a substantially larger capacity to remove the toxic metals by adsorption. The performance analysis was carried out as function of various operating parameters such as contact time, initial concentration, adsorbent dose, and particle size. The parameters affecting kinetics and equilibrium of Cr+6 adsorption onto egg shell powder was studied, Detailed data analysis indicated that the adsorption of chromium followed Freundlich isotherm and Langmuir isotherm.