Facile Synthesis of Hydroxyapatite Particles from Cockle Shells (Anadaragranosa) by Hydrothermal Method

Hydroxyapatite particles, Ca10(PO4)6(OH)2, (HAp), have been successfully synthesized by hydrothermal method using cockle shells (Anadaragranosa) waste as the starting material. The cockle shells were calcined, hydrated (slaking) and undergone carbonation to form precipitated calcium carbonate (PCC). The PCC was added with (NH4)2HPO4 to form HAp by varying the temperatures and reaction times under basic condition (pH 10-11). The X-ray Diffraction (XRD) patterns revealed that the excellent product of HAp with hexagonal crystal structure can obtained via facile hydrothermal procedure (140 ° C for 16 h). Fourier transform infrared spectroscopy (FTIR) spectra analyses showed the presence of OH, HPO4 2-, and PO4 3- absorption bands, indicating the formation of HAp. The dried HAp particles powder was extremely pure with a specific surface area of 17.8 m2/g.