A magnetic nanocomposite produced from camel bones for an efficient adsorption of toxic metals from water

Abstract

Abstract A new, simple, clean, and green procedure for the production of a magnetic nanocomposite (MBBC) from waste camel bone biochar was here described. MBBC particles were in the nano-size range (∼12 nm), having characteristics of both hydroxyapatite and magnetite. The produced nanocomposite was characterized by FT-IR, XRD, TG, SEM, TEM, BET, XRD, Zeta potential and XPS analyses. MBBC exhibited a paramagnetic behavior, having a saturation magnetization of 50.20 emu/g and a mesoporous structure with a BET surface area of 162 m2/g. The FT-IR spectrum of MBBC displayed doublet peaks at 573–601 cm−1 (corresponding to Fe–O vibrations) and a peak at 1046 cm−1 (associated with HPO4), which support the successful formation of MBBC. The maximum adsorption capacities of MBBC, as for the Langmuir isotherm model fittings, were 344.8, 322.6 and 294.1 mg/g for Pb(II), Cd(II) and Co(II), respectively. MBBC showed rapid heavy metals adsorption rates, accomplishing ∼75% adsorption within 5 min. After adsorption accomplishment, MBBC particles were magnetically separated from treated water and heavy metals from saturated MBBC were efficiently desorbed by elution with 0.01 M HCl. Under such elution, the MBBC stability against acid leaching of Fe was proved. Hence, it could be inferred that the production of MBBC from waste camel bones and its utilization for the removal of heavy metals from water is a novel approach within the cleaner production concept.