Paramagnetic Iron-Doped Hydroxyapatite Nanoparticles with Improved Metal Sorption Properties, A Bioorganic Substrates-Mediated Synthesis

摘要

This paper describes the synthesis of para-megnetic iron-containing hydroxyapatite nanoparticles and their increased Cu~(2+) sorbent capacity when using Ca~(2+) complexes of soluble bioorganic substrates from urban wastes as synthesis precursors. A thorough characterization of the particles by TEM, XRD, FTIR spectroscopy, specific surface area, TGA, XPS, and DLS indicates that loss of crystallinity, a higher specific area, an increased surface oxygen content, and formation of surface iron phases strongly enhance Cu~(2+) adsorption capacity of hydroxyapatite-based /materials. However, the major effect of the surface and morphologycal modifications is the size diminution of the aggregates formed in aqueous solutions leading to an increased effective surface available for Cu~(2+) adsorption. Maximum sorption values of 550—850 mg Cu~(2+) per gram of particles suspended in an aqueous solution at pH 7 were determined, almost 10 times the maximum values observed for hydroxyapatite nanoparticles suspensions under the same conditions.