Solid Phase Lipid Extraction of Algal Oil

Extraction is a major cost driver in the production of algal oil. Reducing extraction cost is critical for the economic viability of algal biofuels. This project uses solid phase, hydrophobized silica resin to improve extraction of algal lipids. Process streams containing lipid and other hydrophobic compounds are treated to recover lipids and Corp) for extraction of the algal lipid produced after the Heteroboost process. Hydrophobized resins were evaluated with model triacylglycerides (TAGs) and fatty acids (FFA) to efficacy and selectivity of adsorption of TAGs and FFAs. Resins were then tested in complex mixtures of algal lipids, with or without algal cell debris or biomass. The inability to separate silica from cell debris cleanly ruled out use in these complex mixtures. However, the resins effectively removed algal TAGs and FFAs from clarified aqueous process liquids generated in Phycals aqueous extraction process. Additionally, this efficacy was maintained for 10 adsorption/desorption cycles. Phase II will focus on recovery of hydrophobic compounds from two process streams generated by Phycals aqueous extraction process. The ability to capture algal oil that is currently lost directly improves production cost. Recovering polar lipids that are not currently captured in aqueous extraction will provide additional cost savings. The project will focus on validation of the adsorption/desorption process at the subpilot, documentation of any higher value hydrophobic compounds recovered from this process, scale up of the process to the pilot plant, and develop a cost analysis/model to allow transition to the commercial plants to be constructed in Hawaii. The deliverables will be an optimized reactor design for adsorption/desorption on hydrophobized resins, optimized silica resin, optimized process at subpilot-scale, and field testing of the optimized reactor/methods at pilot-scale. Commercial Applications & amp; Other Benefits: Phycal is constructing a pilot-scale algal oil production facility on the Island of Oahu, Hawaii. This facility is designed to incorporate our existing production methods, but also to be available for testing improvements to these methods that will lower the cost of the algal biofuels that will be produced. This project could have a significant and positive impact on the cost of production of the algal oil by reducing the loss of lipid in process wastestreams and capturing of other hydrophobic compounds that have value either as an additional fuel feedstock or higher value product.