Kinetic and thermodynamic investigation on adsorption of lead onto apatite extracted from mixed fish bone

Abstract

Fish bone derived apatite has been used as adsorbent to remove lead from aqueous solution. The mixed fish bone was treated at three different temperatures starting from 300 °C with an increment of 100 °C. Variation in calcination temperature effects the particle size and the adsorption efficiency of the apatite. The calcined fish bone samples were investigated using XRD, FT-IR, SEM, EDS and XPS. A batch experiment was carried out to examine the effect of pH, initial concentration, and contact time on lead adsorption. The observation shows that the efficiency of adsorption was affected with the contact time, pH, and initial concentration. The highest lead removal efficiency was above 99 %, which was obtained at pH 8 with initial concentration of lead was 25 mg/L and contact time of 60 min. Furthermore, adsorption equilibrium and kinetics of lead were then examined. Kinetics data were analysed by pseudo first and second order models. The adsorption data were then associated with the Langmuir and Freundlich isotherm models. The results obtained indicate that the fish bone derived apatite can be used as an effective adsorbent for removal of Pb(II) from aqueous solution.