Liquefaction of Softwoods and Hardwoods in Supercritical Methanol: A Novel Approach to Bio-Oil Production

  • J. Andres Soria
  • Armando G. McDonald


The production of consistent renewable-based hydrocarbons from woody biomass involves the efficient conversion into stable product streams. Supercritical methanol treatment is a new approach to efficiently convert woody biomass into bio-oil at modest processing temperatures (> 238 °C) and pressures (> 8.1 MPa). The conversion of common Alaskan tree species namely, Alaskan birch and Sitka spruce, was evaluated using the supercritical methanol liquefaction process to yield bio-oil and biochar fractions. Results show that liquefaction of softwoods and hardwoods can be achieved in excess of 90 wt%. The biochar was characterized by Fourier transform infrared spectroscopy and showed that this was lignin derived. The volatile components from the resultant bio-oil were chemically characterized (composition) by gas chromatography-mass spectrometry. The resulting bio-oil was comprised of partially methylated lignin-derived monomers and sugar derivatives which results in a stable and consistent product platform that can be followed by catalytic upgrading into a drop-in-fuel. The broader implications of this novel approach to obtain sustainable bioenergy and biofuel infrastructure are discussed.


Thermochemical Conversion Generation Biofuel Supercritical Methanol Liquid Biofuel Biochar Sample 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This project was supported by USDA-CSREES Wood Utilization Research program grant #2008-34158-19486. The FTIR spectrometer was supported by a USDA-CSREES-NRI equipment grant #2005-35103–15243.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Agricultural and Forestry Experiment StationUniversity of Alaska FairbanksPalmerUSA
  2. 2.School of EngineeringUniversity of Alaska AnchoragePalmerUSA
  3. 3.Renewable Materials Program, College of Natural ResourcesUniversity of IdahoMoscowUSA

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