Thermal Treatment of Crude Algae Oils Prepared Under Hydrothermal Extraction Conditions

We demonstrate that removal of oxygen and metals from crude algae oils produced by hydrothermal treatment processes is possible by thermal means alone and without the use of catalysts or hydrogen. Thermal treatment can reduce the total amounts of acids in the crude algae oil and thus decrease the total acidity of the oil. Thermal treatment also reduces the boiling point range of crude algae oils, making them more volatile and less viscous, benefitting shipping and upgrading. Trace metals are significantly reduced as the thermal treatment temperature increases. The results obtained in this study are consistent with existing theories of the formation of petroleum crude oils and create a link between the upgrading of crude algae oils and the mechanisms involved in the formation of conventional fossil fuels. The results and possible pathways of the reaction mechanisms are presented.

[1]  Y. Chisti.  Biodiesel from microalgae. , 2007, Biotechnology advances.

[2]  Phillip E. Savage,et al.  Hydrothermal Liquefaction and Gasification of Nannochloropsis sp. , 2010 .

[3]  Philip Owende,et al.  Biofuels from microalgae—A review of technologies for production, processing, and extractions of biofuels and co-products , 2010 .

[4]  P. Biller,et al.  Potential yields and properties of oil from the hydrothermal liquefaction of microalgae with different biochemical content. , 2011, Bioresource technology.

[5]  D. Fabbri,et al.  Hydrothermal Treatment (HTT) of Microalgae: Detailed Molecular Characterization of HTT Oil in View of HTT Mechanism Elucidation , 2012 .

[6]  K. Das,et al.  Effect of operating conditions of thermochemical liquefaction on biocrude production from Spirulina platensis. , 2011, Bioresource technology.

[7]  Prasant Kumar Rout,et al.  Production of first and second generation biofuels: A comprehensive review , 2010 .

[8]  P. Biller,et al.  Catalytic hydrothermal processing of microalgae: decomposition and upgrading of lipids. , 2011, Bioresource technology.

[9]  Morgan Fröling,et al.  Thermochemical biofuel production in hydrothermal media: A review of sub- and supercritical water technologies , 2008 .

[10]  L. Rosendahl,et al.  Hydrothermal liquefaction of biomass: A review of subcritical water technologies , 2011 .

[11]  Phillip E. Savage,et al.  Characterization of Product Fractions from Hydrothermal Liquefaction of Nannochloropsis sp. and the Influence of Solvents , 2011 .

[12]  Q. Hu,et al.  Microalgal triacylglycerols as feedstocks for biofuel production: perspectives and advances. , 2008, The Plant journal : for cell and molecular biology.

[13]  Michimasa Kishimoto,et al.  Oil production from algal cells of Dunaliella tertiolecta by direct thermochemical liquefaction , 1995 .

[14]  Jacinto F. Fabiosa,et al.  Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change , 2008, Science.

[15]  Yutaka Dote,et al.  Recovery of liquid fuel from hydrocarbon-rich microalgae by thermochemical liquefaction , 1994 .

[16]  Douglas C. Elliott,et al.  Historical Developments in Hydroprocessing Bio-oils , 2007 .

[17]  Sascha R.A. Kersten,et al.  Hydrothermal Treatment (HTT) of Microalgae: Evaluation of the Process As Conversion Method in an Algae Biorefinery Concept , 2012 .

[18]  Anoop Singh,et al.  Renewable fuels from algae: an answer to debatable land based fuels. , 2011, Bioresource technology.

[19]  Amanda Lea-Langton,et al.  Hydrothermal processing of microalgae using alkali and organic acids , 2010 .

[20]  Shicheng Zhang,et al.  Hydrothermal Liquefaction of Macroalgae Enteromorpha prolifera to Bio-oil , 2010 .