Equilibrium kinetic studies on biosorption of zinc onto Gallus domesticus Shell Powder

Biosorption is potentially an attractive technology for treatment of wastewater for retaining heavy metals from dilute solutions. Studies carried through the environmental biotechnology have shown that many biosorbents present in the nature have great capacity for removal of heavy metals. The paper presents the results of studies carried out on sorption of zinc ions from aqueous solutions by Gallus Domesticus shell powder as a low-cost sorbent. It was found that crushed Gallus Domesticus shell posse’s relatively high sorption capacity, when comparing with other sorbents that was evaluated as 46.05 mg/g. The biosorption experiments were performed under various conditions such as different initial concentrations, pH, biosorbent concentration and biosorbent particle size. It was found that the equilibrium of the process was reached after 60 min. About 0.1g of Gallus Domesticus shell powder was found to be enough to remove 86.50 % of zinc for 20 mg/l of metal ion concentration from 30 ml aqueous solution. The optimum pH value was found to be 6. The pseudo first order and pseudo second order kinetic models were used to describe the kinetic data. The dynamic data fitted with the pseudo second order kinetic model for zinc. The experimental equilibrium data were adjusted by the biosorption isotherms from Langmuir, Freundlich, Redlich & Peterson and Temkin models, and their equilibrium parameters were determined. The best-adjusted model to the experimental equilibrium data for egg shell powder was the Freundlich mode