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DOE OSTI · 1039789

Algae Biofuels Collaborative Project (CRADA Final Report)

French, Richard J.
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Abstract

The goal of this project is to advance biofuels research on algal feedstocks and NREL's role in the project is to explore novel liquid extraction methods, gasification and pyrolysis as means to produce fuels from algae. To that end several different extraction methods were evaluated and numerous gasification and pyrolysis conditions were explored. It was found that mild hydrothermal treatment isa promising means to improve the extraction and conversion of lipids from algae over those produced by standard extraction methods. The algae were essentially found to gasify completely at a fairly low temperature of 750 °C in the presence of oxygen. Pyrolysis from 300-550 °C showed sequential release of phytene hydrocarbons, glycerides, and aromatics as temperature was increased. It appears that this has potential to release the glycerides from the non-fatty acid groups present in the polar lipids to produce a cleaner lipid. Further research is needed to quantify the pyrolysis and gasification yields, analyze the liquids produced and to test strategies for removing organic-nitrogen byproducts produced because of the high protein content of the feed. Possible strategies include use of high-lipid/low-protein algae or the use of catalytic pyrolysis.

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09 BIOMASS FUELS59 BASIC BIOLOGICAL SCIENCESALGAEAROMATICSBIOFUELSCRADAGASIFICATIONHYDROCARBONSLIPIDSOXYGENPROTEINSPYROLYSIS

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French, Richard J.. 2012-04-01. Algae Biofuels Collaborative Project (CRADA Final Report). https://doi.org/10.2172/1039789

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