Changes in hydroxyapatite powder properties via heat treatment

Abstract

The properties of hydroxyaptite (HA) powder, especially its physical one, are largely influenced by the heat treatment process. Controlling of these changes is vital in deciding the suitability of applying this powder in wet processing routes for green body fabrication. Chemically, the crystallinity of the HA powder was found to be largely enhanced with the increase in calcination temperatures. In contrary, a high retardation in the carbonate ion content was found. Physically, all the powder properties in terms of particle size, its distribution, pore volume, pore size and surface area are considerably varied with calcination temperatures. It was found that HA powder calcined at both 1000 and 1100 • C possesses reasonable physico-chemical properties for being applied in wet processing routes. Using heat-treated powder at 1000 and 1100 • C with 0.3 wt% sodium polyacrylate (as a dispersing agent) turned out to be beneficial in developing a low viscosity and high turbidity suspensions.

The effect of sintering temperature on characteris-tic and properties of hydroxyapatite extracted from fish scale bio-waste

“…Increase in calcination temperature produced a narrow stretching band of adsorbed denoted by water wavelength 2357.01cm-1. The results were in agreement with Ahmed et al [26] which reported adsorbed water becomes narrower under the treatment of heat. Another significant peak attributed to CO3 2also found at wavelength 1409.96 cm -1 and 1186.22 cm -1 .…”

“…The absorption band is observed at wavelength 2360.87cm -1 attributed to stretching band confirmed presence of OH -. An earlier report by Ahmed et al [26], has mention presence of OHin the sample of hydroxyapatite when sintered at 900 o C. Fig.2 (e) represent FSHAp-1000 display by broad-spectrum contains functional group attribute to OHwith ion stretching mode ranging from wavelength 3400 cm -1 which engaged in amorphous solid. Asymmetric stretching of CO3 2is observed at wavelength 1406.11 cm -1 while the asymmetric stretching mode belongs to PO4 2at wavelength was detected at wavelength 1012.63 cm -1 .…”

Tailoring the morphological features of sol–gel synthesized mesoporous hydroxyapatite using fatty acids as an organic modifier

“…The presence of broad peaks reveals the occurrence of smaller-sized particles, compared to samples prepared without SA. 30 The presence of SA in the precipitation of HAP has a strong inuence in the particle size. The average crystallite size of the HAP samples calculated using Debye-Scherrer's equation is given in Table 1.…”

Role of strontium substitution in spray drying of hydroxyapatite: A comparative study on physical properties

“…Spray dried granules presented the highest degree of SSA and total pore volume. The heat treatment decreased the SSA and total pore volume due to growth and necking of HA nanoparticles during the sintering process . The SSA and total pore volume of the SD‐HA and SD‐8SrHA decreased sharply to the lower degrees after the heat treatment at 1000°C.…”