Removal of Cu(II) ions from water using thermally-treated horn–hoof powder as biosorbent

In this work, thermally-treated “horn–hoof” powder was studied as biosorbent to remove copper (II) ions from aqueous solutions. Adsorption of copper onto horn–hoof powder was tested in batch process at different experimental conditions. The effect of the initial metal ion concentration, biosorbent dosage, contact time, pH and temperature were investigated with respect to the biosorption characteristics of Cu(II) ion on the horn–hoof powder. The biosorbent characterization was carried out by Fourier transform infrared spectroscopy, mini-cell electrophoresis, BET and particle sizing analysis. According to the tests, the adsorption equilibrium time was reached within 48 h and the optimum adsorption of Cu(II) ions took place at the pH value of 5.5. The Langmuir adsorption isotherm was successfully applied to the biosorption process of Cu(II) ions onto horn–hoof powder. The thermodynamic and kinetic data suggested that the biosorption process is an endothermic process involving chemical reactions and following a pseudo-second-order model.