Patent ID: 9120987
Filing Date: 2015-09-01
Classification: B01D,C02F,C10L,C11B,C12P

Abstract:
1. A method of separating neutral lipids from intact algal cells, comprising: providing a wet algal biomass comprising intact algal cells which comprise proteins that are soluble in an amphipathic solvent, polar lipids and neutral lipids; dewatering the wet algal biomass by removing extracellular water to increase the solid content of the wet algal biomass to between 5% and 50% to generate a partially dewatered wet algal biomass; mixing the partially dewatered wet algal biomass with a first amphipathic solvent set in a ratio of about one part first amphipathic solvent set to about one part wet algal biomass by weight, and a first hydrophobic solvent set to generate a first extraction mixture comprising a first heavier phase and a first lighter phase, wherein the first heavier phase comprises the first amphipathic solvent set, neutral lipids, proteins that are soluble in an amphipathic solvent, and partially dewatered wet algal biomass and the first lighter phase comprises the first hydrophobic solvent set and polar lipids; separating the first lighter phase of the extraction mixture from the first heavier phase of the extraction mixture; separating the partially dewatered wet algal biomass from the first amphipathic solvent set in the first heavier phase of the extraction mixture to generate a separated partially dewatered wet algal biomass comprising neutral lipids; and a protein mixture comprising proteins that are soluble in an amphipathic solvent, water and the first amphipathic solvent set; mixing the separated partially dewatered algal biomass with a second amphipathic solvent set in a ratio of about one part second amphipathic solvent set to about one part separated partially dewatered wet algal biomass by weight, and a second hydrophobic solvent set to generate a second extraction mixture comprising a second heavier phase and a second lighter phase, wherein the second heavier phase comprises the second amphipathic solvent set and separated partially dewatered wet algal biomass and the second lighter phase comprises the second hydrophobic solvent set and the neutral lipids; separating the second heavier phase from the second lighter phase; recycling at least a portion of the second heavier phase for further mixing with a third amphipathic solvent set in a ratio of about one part third amphipathic solvent set to about one part separated partially dewatered wet algal biomass by weight, and a third hydrophobic solvent set to generate a third extraction mixture comprising a third heavier phase and a third lighter phase, wherein the third heavier phase comprises the third amphipathic solvent set and separated partially dewatered wet algal biomass and the third lighter phase comprises the third hydrophobic solvent set and the neutral lipids; separating the third heavier phase from the third lighter phase; and separating the neutral lipids from the second lighter phase and the third lighter phase, wherein the first lighter phase has a higher concentration of polar lipids than the second and third lighter phases, and the second and third lighter phases have a higher concentration of neutral lipids than the first lighter phase.