Wet synthesis of carbonated hydroxyapatite

Carbonated hydroxyapatite of predominant B-type of substitution has been synthesized at various temperatures, carbonate concentrations and time of immersion in mother solution. Carbonated hydroxyapatite synthesized at 80 °C contains the largest amount (up to 9 wt.%) of calcite impurity and has a low specific surface area (40 m2/g). Lowering the synthesis temperature to 20 °C leads to a slight decrease in the content of calcite impurity (up to 5–7 wt.%) and an increase in the specific surface up to 125 m2/g. The introduction of the maturation stage for carbonated hydroxyapatite precipitated at 20 °C for 4 days suppresses the calcite impurity formation and leads to the increase in the specific surface up to 155 m2/g.