Table 2.
Thermal decomposition of HA. V represents a vacancy and x < 1 [72].
| Ca10(PO4)6(OH)2 → Ca10(PO4)6(OH)2-2xOxVx + xH2O | (1) |
| Hydroxyapatite → Oxyhydroxyapatite (OHA) | |
| Ca10(PO4)6(OH)2-2xOxVx → Ca10(PO4)6OxVx + (1-x)H2O | (2) |
| Oxyhydroxyapatite → Oxyapatite (OA) | |
| Ca10(PO4)6OxVx → 2Ca3(PO4)2 + Ca4O(PO4)2 | (3) |
| Oxyapatite → Tricalcium phosphate (TCP) + Tetracalcium phosphate (TTCP) | |
| Ca3(PO4)2 → 3CaO + P2O5 | (4a) |
| Tricalcium phosphate → Calcium oxide + Phosphorus pentoxide | |
| Ca4O(PO4)2 → 4CaO + P2O5 | (4b) |
| Tetracalcium phosphate → Calcium oxide + Phosphorus pentoxide |