One-pot catalytic hydrocracking of diesel distillate and residual oil fractions obtained from bio-oil to gasoline-range hydrocarbon fuel

Bio-oil can be fractionated into three parts according to their boiling point. Here we report that diesel distillate and residual oil fractions can be converted into high-quality fuels by catalytic hydrocracking with the combined CoMoS/Al2O3 and HZSM-5 catalysts. Under the conditions of 390 °C and 6 MPa H2, a high yield (87.0 wt.%) of liquid products was obtained. The compositions were C7-C14 hydrocarbons, including 23.3% of saturated naphthene, 23.4% of saturated chain hydrocarbons, 30.5% of aromatic hydrocarbons, and 22.8% of polycyclic aromatic hydrocarbons with one of ring saturated. The high heating value of products was 42.35 MJ/kg. The amounts of coking was only 1.15 wt.%, and the combined catalysts were recycled three times without the obvious decline of activity. Moreover, the reaction process did not need any solvent, and the products were easily separated. Based on the material balance, the net hydrogen consumption for the hydrocracking process was 38 g of H2/kg of bio-oil, and the energy efficiency could reach up to 84%. This approach provides a high-efficiency route for the preparation of high-quality hydrocarbon fuel from bio-oil.