Abstract
Calcium phosphate hydroxyapatite, Ca10(PO4)6(OH)2, is a typical apatite compound which has a high thermal stability and an affinity for organic compounds of biomass derivatives. It has a capacity for substitutions of Ca2+ ions and PO43- ions by other cations and anions. Here in, we will report the selective conversions of biomass derivatives, such as ethanol and lactic acid, into useful chemicals over the apatite compounds, such as Ca10(PO4)6(OH)2, Sr10(PO4)6(OH)2, Pb10(PO4)6(OH)2, and Ca10(VO4)6(OH)2. The apatite compounds were powders prepared by the hydrothermal method. In the ethanol conversion, the Sr-P apatite catalyst exhibited high 1-butanol selectivity (sel. > 80 C-%), which was significantly higher than that over the Ca-P apatite catalyst. In contrast, the Pb-P apatite catalyst selectively gave acetaldehyde, and the Ca-V apatite catalyst accelerated the dehydration into ethylene.
