Patent ID: 6043063
Filing Date: 2000-03-28
Classification: C08G,C08J,C12P,Y02W

Abstract:
A method of recovering polyhydroxyalkanoate (PHA) from biomass comprising:providing biomass containing PHA;dissolving PHA with a solvent to produce PHA-enriched solvent and residual biomass materials;separating the residual biomass materials from the PHA-enriched solvent; andrecovering PHA polymer from the PHA-enriched solvent, wherein:the PHA is selected from the group consisting of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (3HB4HB), and polymers and copolymers of hydroxyterminated polyhydroxybutyrate (PHB-OH); andwhen the PHA is 3HB4HB or PHB-OH, the solvent is selected from the group consisting of: cyclic and acyclic R'--OH alcohols where R'=C.sub.4 -C.sub.10, dimethyl glutarate, dimethyl adipate, isobutyl acetate, ethyl lactate, isoamyl acetate, benzyl acetate, 2-methoxy ethyl acetate, tetrahydrofurfuryl acetate, propyl propionate, pentyl propionate, butyl butyrate, isobutyl isobutyrate, ethyl butyrate, ethyl valerate, methyl valerate, benzyl benzoate, methyl benzoate, methyl propionate, allyl alcohol, tetrahydrofurfuryl alcohol, furfuryl alcohol, ethyl benzene, 1,3-dimethoxybenzene, cumene, benzaldehyde, 2-furaldehyde, 1,2-propanediol, 1,2-diaminopropane, ethylene glycol diethyl ether, 1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene, 1,3-dioxane, 1-nitropropane, toluene-2,4-diisocyanate, acetic acid, acrylic acid, acetic anhydride, methyl isobutyl ketone, methyl n-amyl ketone, 5-methyl-2-hexanone, acetophenone, dimethyl acetamide, alpha-methyl styrene, and propylene carbonateand when the PHA is PHBV, the solvent is selected from the group consisting of cumene, benzaldehyde, 2-furaldehyde, toluene-2,4-diisocyanate, alpha-methylstyrene, acetic acid, acrylic acid, acetic anhydride, 1,2-diaminopropane, 1-nitropropane, and an amyl alcohol mixed isomeric solution comprising 1-pentanol, 2-methyl-1-butanol, and 3-methyl-1-butanol.