Biosorption of Ni(II), Pb(II) and Zn(II) on calcium alginate beads: equilibrium, kinetic and mechanism studies

The biosorption process of three divalent metal ions - nickel, lead and zinc-from on calcium alginate from aqueous solution was studied, in single component systems. The biosorbent were investigated by Fourier Transform Infrared Spectroscopy. The batch mode experiments of the adsorption process were carried out as a function of pH, initial metal ions concentration, sorbent dosage and contact time. The adsorption influencing parameters for the maximum removal of metal ions were optimized. The experimental data were analyzed using the Langmuir, Freundlich, Langmuir-Freundlich, Koble-Corrigan and Redlich-Peterson models. The kinetic data of biosorption process were evaluated using pseudo-first and pseudo-second order equations. The Weber and Morris model was employed to interpret the metal ions diffusion in biosorption process.