Synthesis and Sintering-wet Carbonation of Nano-sized Carbonated Hydroxyapatite

Synthetic carbonated apatite ceramics are considered as promising alternative to auto- and allograft materials for bone substitute. In this study, Carbonated hydroxyapatite (CHA) was synthesized by nanoemulsion method. The powder produced was B-type CHA in nano-sized and had 8.25% carbonate content. The CHA samples were made into pellets and were sintered to 800 °C. Upon cooling down to 150, 200, 250 and 300 °C, carbonation with wet CO2 was performed on the CHA in a desiccator to re-compensate the carbonate loss due to sintering and improve densification. The aim of this study was to investigate and compare the effect of cooled down temperatures on dense CHA with two kind of wet CO2 atmospheres: direct wet CO2 and dry CO2 through water. Sintered CHA carbonated by using dry CO2 through water had overall higher amount of carbonate content as compared to carbonation from wet CO2 directly from tank. D200, sample undergone carbonation by carbonated by dry CO2 through water at 200 °C had the highest carbonate content (3.35%).