Fabrication of biphasic calcium phosphate bioceramics from the recycling of bone ash

Biphasic calcium phosphate bioceramics were fabricated from the recycling of bone ash which is mostly used as raw materials of bone china. Precursor calcium phosphate powders were prepared by soaking the commercial bone ash in 0.1 M of NaOH solution at 80 degrees C for 4 h. Calcium phosphate powders was obtained by calcination at 800 degrees C for 1 h to completely remove residual organics. Biphasic calcium phosphate bioceramics which is composed of hydroxyapatite and tricalcium phosphate was fabricated by the sintering of pressed compacts at 1200 degrees C for 1 h under moisture protection. The bone ash derived-biphasic calcium phosphate ceramics consists of mostly HA and small amounts of alpha-tricalcium phosphate, magnesium oxide and calcium oxide. After polishing the HA ceramics, they were immersed in buffered water at 37 degrees C for 3 and 7 days. The bone ash derived- biphasic calcium phosphate ceramics show high biostability in liquid environment with immersion time compared with commercial calcium phosphate ceramics.