Efficient one-pot process to convert bio-oil fractions to gasoline-range hydrocarbons
24 July 2015
A team at South China University of Technology has developed a one-pot process to convert the diesel distillate and residual oil fractions in bio-oil into high-quality fuels by catalytic hydrocracking with combined CoMoS/Al2O3 and HZSM-5 catalysts. A paper on their process is published in the journal Fuel.
Bio-oil—the end product of biomass pyrolysis—can be distilled into three fractions according to their boiling points—essentially light, medium and heavy. The light fraction is mostly water.
Under the conditions of 390 °C and 6 MPa H2, the researchers obtained a high yield (87.0 wt.%) of liquid products from the catalytic conversion of the medium and heavy fractions. The end product was 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 amount 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%.
The results suggested that the approach provides a high-efficiency route for the preparation of high-quality hydrocarbon fuel from bio-oil.
Resources
Xianwei Zheng, Jie Chang, Yan Fu (2015) “One-pot catalytic hydrocracking of diesel distillate and residual oil fractions obtained from bio-oil to gasoline-range hydrocarbon fuel,” Fuel, Volume 157, Pages 107-114, doi: 10.1016/j.fuel.2015.05.002
Christian Lindfors, Eeva Kuoppala, Anja Oasmaa, Yrjö Solantausta, and Vesa Arpiainen (2014) “Fractionation of Bio-Oil” Energy & Fuels 28 (9), 5785-5791 doi: 10.1021/ef500754d
Comments