Synthesis of Femur extracted hydroxyapatite reinforced nanocomposite and its application for Pb(II) ions abatement from aqueous phase.

This research study shows the adsorptive potential of biopolymer based nanocomposite for the removal of Pb(II) ions from aqueous phase. The nanocomposite was synthesized by Femur calcined hydroxyapatite and glutaraldehyde cross-linked chitosan. Characterizations like Fourier Transform Infrared (FTIR) Spectroscopy, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were performed to investigate the structural modifications, mineral composition and the surface texture of prepared nanocomposite. The adsorption of Pb(II) ions over nanocomposite reveals that the synthesized solid sorbent has promising abatement tendency for heavy metal ions. The adsorption process followed the pseudo-second-order kinetics and the equilibrium data of lead ions adsorption was best fitted to Sips isotherm model. The uptake capacity of synthesized nanocomposite increased from 209 mg/g to 354 mg/g with rise in temperature from 18 °C to 48 °C. The thermodynamic analysis suggested that the Pb(II) ions adsorption was spontaneous and endothermic in nature. Additionally, enthalpy of adsorption (~22.07 KJ/mol) indicated that the heavy metal ions were chemisorbed over nanocomposite surface. Adsorption of Pb increased about ~1.6 times in the observed pH range and highest uptake was obtained at pH 5.