Application of Waste Egg Shell for Adsorption of Cd(II) and Pb(II) Ions to Protect Environment: Equilibrium, Kinetic and Adsorption Studies

Abstract

In the present work, we studied the impact of adsorption parameters on adsorption of M (II) [Cadmium and Lead] using calcinated chicken egg shell as biomaterial. The characterization of biomaterial reveals; crystallite size by Scherrer formula is 66.58 nm and 9.80 m2/g BET surface area. The adsorption of cadmium and lead on calcinated egg shell was found to be dependent on equilibrium adsorption parameters. The adsorption kinetic models and adsorption isotherm were successfully applied. The removal method was validated with anodic stripping voltametric technique. For standard aqueous sample of M (II), maximum removals were obtained at pH 5 and 200 mg of adsorbent and 120 minutes of contact time. The kinetic model followed pseudo second order kinetics at equilibrium contact time of 120 minute. The amounts of M (II) adsorbed per unit mass of calcinated egg shell increases with initial concentration up to 50 mg/L followed by deviation in results were observed. The Freundlich’s adsorption isotherm model is better fitted for M (II) adsorption with R2 closed to unity i.e0.9998 for Cadmium and 0.9983 for Lead. For real samples, adsorbed M (II) also recovered with 98 + 0.5 % recovery using 10 ml of 1.0 M HCl with flow rate of 2 ml per minute.