Comparative study between chemical precipitation and chemical precipitation by spraying for the recovery of nanometric hydroxyapatite

Abstract

The aim of this work was to develop a new method of assisted precipitation by spraying to obtain nanometer-sized hydroxyapatite and to compare it with conventional chemical precipitation by droplets. Scanning electron microscopy showed the morphological characteristics flake-like of HAp particles synthesized by the spray method at different reaction times and the formation of HAp from the first reaction time, which is different from the droplet method. X-ray diffraction confirmed the crystal structure and size of the synthesized HAp by Rietveld refinement, showing a crystallite size of about 3.77 nm for the spray synthesis and 18 nm for the droplet synthesis. FTIR and Raman were used to analyze the active normal vibrational modes of the synthesized HAp. The results showed that in the spray system, HAp formation occurs at the beginning of the reaction, a phenomenon that was not observed in the droplet method. In particular, FTIR analysis showed the presence of phosphate and carbonate modes of HAp as early as 9 minutes, which persisted throughout the reaction. This Furthermore, dynamic light scattering measurements show that the size distribution of HAp particles synthesized using the novel spray system is between 2 and 5 μm. This shows that the distribution with the spray method is more stable than with the droplet method, which shows the presence of irregular particles with a size distribution at 3 μm. The results emphasize the effectiveness of the proposed method in producing HAp with desirable properties for various biomedical applications.