Catalytic conversion of polyols (sorbitol and xylitol) to hydrocarbons over hierarchical ZSM-5 zeolite catalysts in a fixed bed reactor

Abstract

The catalytic activity of hierarchical ZSM-5 zeolites was investigated in the polyols (sorbitol and xylitol) to hydrocarbons conversion in a fixed bed reactor under atmospheric pressure by altering different parameters. A lower sorbitol and xylitol conversion was achieved at the reaction temperature of 375 °C, whereas a higher value of 92.33 and 88.19% sorbitol conversion, 95.58 and 92.32% xylitol conversion was obtained when the reaction temperature was further elevated to 425 °C for ZSM-5-WS(28) and ZSM-5-WOS(28) catalysts. Other important parameters, such as substrate concentration, weight hourly space velocity (WHSV) and Si/Al ratio strongly influenced the polyols to hydrocarbons conversion reaction. The optimal conditions are substrate concentration (sorbitol/xylitol) of 15%, WHSV of 1.0 h−1, reaction temperature of 425 °C. In addition to that, the recycling performances of the ZSM-5 catalysts were carried out for four runs and the catalysts were showed better recycling performance and stability.