Patent ID: 7378266

Claim:
An improved process for extracting polyhydroxyalkanoate from a biomass containing the polyhydroxyalkanoate comprising the steps of: a) combining the biomass containing the polyhydroxyalkanoate with a solvent selected from the group consisting of lower chain ketones, and mixtures thereof to form a biomass liquor wherein the biomass liquor comprises less than about 25% water; b) mixing the biomass liquor for from about 10 to about 300 minutes at a temperature in the range of from about 70° C. to about 120° C.; c) separating the polyhydroxyalkanoate from the biomass liquor to form a PHA-enriched liquor, wherein the separating occurs at a temperature of at least about 40° C.; d) mixing the PHA-enriched liquor with water to form precipitated polyhydroxyalkanoate and an impure solvent liquor, wherein the water is mixed with the PHA-enriched liquor in the ratio of from at least about 3 parts water to one part polyhydroxyalkanoate; and e) recovering the precipitated polyhydroxyalkanoate from the impure solvent liquor.