Eco-friendly synthesis and characterization of hydroxyapatite nanoparticles from Syrian phosphate ore

Abstract

Hydroxyapatite Nanoparticles (HAp-NPs) were Synthesized by dissolution and reprecipitation methods from Syrian Phosphate Ore as an economical, Renewable source of phosphate and calcium. The phosphate ore sample was dissolved using 0.5M nitric acid, leading to the liberation of calcium and phosphate ions. subsequently, 25% ammonium hydroxide was added to the resulting filtrate as an alkaline precipitating agent in order to precipitate hydroxyapatite. XRD analysis revealed the phase purity of the synthesized material, showing characteristic peaks of hydroxyapatite with Crystallite size 49.13 nm. while FT-IR results revealed the presence of functional groups such as phosphate groups denoting the successful synthesis of hydroxyapatites nanoparticles. FESEM images Showed hydroxyapatite deposition as agglomerated crystalline clusters Also, the obtained (HAp-NPs) has Ca/P molar ratio of 2.09 and exhibited high total surface area of 73 m²/g. AFM images confirmed the hydroxyapatite formation in the particle range between 70 nm and 90 nm. Thermogravimetric and differential thermal analysis (TGA/DTA) demonstrated the high thermal stability of HAp-NPs up to 800 °C. The obtained results show that Syrian phosphate ore is an inexpensive, eco-friendly precursor as a starting material for hydroxyapatite nanoparticles synthesis with wide applications in biomedical, environmental, and industrial processes.