Hydrothermal Synthesis of nanocrystalline powders of alkaline-earth hydroxyapatites, A10(PO4)6(OH)2 (A = Ca, Sr and Ba)

In the present work, we report a direct precipitation of nanocrystalline powders of alkaline-earth hydroxyapatites of the compositions, A10(PO4)6(OH)2 (A = Ca, Sr or Ba) from aqueous solutions containing Na3PO4 and MCl2 (M = Ca, Sr or Ba) at 150◦C for 2 days and autogeneous pressure under hydrothermal conditions. The products were characterized by X-ray powder diffraction, transmission electron microscopy and scanning electron microscopy. The paper also discusses a convenient and economical hydrothermal route for the extraction of nanocrystalline calcium hydroxyapatite, from fish bone waste. C 2006 Springer Science + Business Media, Inc.