Optimization of renewable C5 and C6 alkane production from acidic biomass hydrolysate over Ru/C catalyst

In this work, a dual-bed aqueous catalysis system with Ru/C as catalyst was proposed for the liquid alkane (pentane/hexane: C5/C6) production from acid biomass hydrolysate. The low temperature (413   K) hydrogenation of biomass-derived carbohydrates into polyols was carried out in the first fixed-bed. The high temperature (523   K) hydrodeoxygenation (HDO) of polyols into alkanes was carried out in the down-stream bed. To screen the optimal reaction conditions, glucose and sorbitol were chosen for model tests. Whereby, reactor types, solution pH value, mineral acid, reaction temperature, pressure and sorbitol concentrations were studied. A maximum C5/C6 alkane yield of 61.9% was achieved from 20   wt% sorbitol solution (pH   =   1.5) under 523   K and 4   MPa H 2 pressure in the fixed-bed reactor. For cassava and corncob hydrolysate, C5/C6 alkane yield of 38.8% and 44.1% were obtained, respectively.