Applied Catalysis A: General, Vol.542, 136-145, 2017
Carbonate hydroxyapatite as a catalyst for ethanol conversion to hydrocarbon fuels
Carbonate hydroxyapatite (CHAP) was successfully used as a catalyst for direct ethanol conversion into hydrocarbon fuels in a single-step gas-phase reaction. The CHAP was synthesized by chemical precipitation method in basic media using an alkali-free system. After heat treatments, it was widely characterized by XRF, XRD, FTIR, XPS, pyridine-TPD, CO2 chemisorption, and N-2 adsorption at -196 degrees C. The physical-chemical analysis indicates the formation of B-type CHAP and the presence of acid and basic surface sites being able to act as a bifunctional catalyst. Under optimum conditions of reaction temperature (500 degrees C) and modified residence time W/F-Ethanot (40 g h mol(-1)), the ethanol conversion showed a high yield (approximate to 97%) to a mixture of non oxygenated and oxygenated hydrocarbon fuels with carbon chain lengths in the range from C-4 to C18+. After condensation of the reaction products an oily and one aqueous phases were obtained. The net calorific value (NCV) of the oily phase (approximate to 41.3 MJ kg(-1)) was close to those found in conventional fossil fuels.