DEOXYGENATION OF CARBOHYDRATES AND THEIR ISOPROPYLIDENE DERIVATIVES OVER ZSM-5 ZEOLITE CATALYSTS

The catalytic conversion of D-glucose, D-fructose and their isopropylidene derivatives over H-ZSM-5, Zn-ZSM-5 and Mn-ZSM-5 zeolite catalysts to deoxygenated compounds have been studied in a fixed-bed microreactor. Low yields of deoxygenated hydrocarbons were obtained due to significant thermal polymerization of the carbohydrates at reaction temperatures of 350 degree C and higher. Increasing the (H : C) //e//f//f ratio of the feed with methanol did not result in any significant increase of the hydrocarbon yields for the carbohydrates. Reaction mechanisms for polymerization and volatile products from the carbohydrates at high temperatures are discussed.