(723e) Hydrodeoxygenation and Hydroisomerization of Algae Oils to Hydrocarbon Fuels

Microalgae are a promising feedstock for renewable fuels and chemicals because of their potentially high growth rate and lipid content. Recent interest in converting the lipid fraction into completely deoxygenated jet- and diesel-range fuels has motivated research and development efforts in catalyst and process development for deoxygenation and isomerization steps for these lipids, but literature data for algal lipid composition with respect to its effects on DO and HI is sparse. In this work, we report detailed characterization of the extracted lipids as well as deoxygenation (DO) and hydroisomerization (HI) of the lipids extracted from mid-stage (high-carbohydrate content) Scenedesmus algae. Over a Pd/C catalyst, nearly complete deoxygenation is achievable, and the DO product is readily isomerized over a Pt/SAPO-11 catalyst. The isomerized product has boiling points primarily in the diesel range and cloud points < -10 °C. Minimal cleanup of the oils is required prior to catalytic upgrading, but bleaching with SiO2 or H3PO4 results in a product with lower nitrogen content.