Synthesis of Calcium Phosphates with Various Ca/P Ratios Using Phytic Acid as a Green Phosphorus Source

Abstract

The synthesis of calcium phosphate from natural phosphorus sources has attracted attention because it saves finite resources. Herein, a novel approach for the synthesis of calcium phosphates using phytic acid as a natural phosphorus source was developed. Calcium phytate was synthesized from phytic acid and calcium chloride, which was mixed with calcium chloride to adjust the Ca/P ratio in the range of 1.0–1.67. The calcination at a temperature of 1100 °C of the mixtures yielded various calcium phosphates, including β-calcium pyrophosphate, β-tricalcium phosphates (β-TCP), and hydroxyapatite (HAP), depending on the Ca/P ratio in the mixtures. Additionally, the X-Ray diffraction (XRD) analysis revealed that α-calcium pyrophosphate, spodiosite, and chlorapatite (ClAP) are formed as intermediates during the calcination process.