PROCESS FOR LIQUID/SOLID SEPARATION OF LIGNOCELLULOSIC BIOMASS HYDROLYSATE FERMENTATION BROTH

• US 20120178976A1
• Filed: 04/25/2011
• Published: 07/12/2012
• Est. Priority Date: 04/28/2010
• Status: Active Grant

• Current Assignee: Sustainable Technology Corporation
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Hennessey, Susan Marie, Mitchell, Annemarie, Stolarski, Mathias E., Wood, James Gregory
• Granted Patent: US 8,906,235 B2
• Time in Patent Office: Days
• US Class Current: 568/913
• CPC Class Codes: C12P 1/00 Preparation of compounds or compositions, not provided for in groups C12P3/00 - C12P39/00, by using microorganisms or enzymes
• CPC Class Codes: C12P 7/10 substrate containing cellulosic material
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

When lignocellulosic biomass hydrolysate is included in fermentation medium, the broth resulting from biocatalyst production is complex with low filterability. A heat treatment was found to increase filterability, allowing efficient separation of a liquid fraction from a solid fraction, which is further processed for water recycle and syrup production.

Claims

1. A process for separating a liquid fraction from a lignocellulosic biomass hydrolysate fermentation broth comprising:

a) providing a lignocellulosic biomass hydrolysate fermentation broth comprising a target product;

b) optionally removing the target product from the lignocellulosic biomass hydrolysate fermentation broth of (a), producing a depleted broth;

c) treating the broth of (a) or depleted broth of (b) at a temperature and for a time sufficient to produce a broth or depleted broth having at least about 20% reduced filter cake resistance as compared to the respective starting broth of (a) or depleted broth of (b); and

d) passing the treated broth or depleted broth of (c) through a filter, thereby separating a liquid fraction from a solid fraction.

2. The process of claim 1 wherein the treating step of (c) is at a temperature between about 70°

C. and about 150°

C.

3. The process of claim 2 wherein the temperature is between about 95°

C. and about 150°

C.

4. The process of claim 1 wherein the time of treating in step (c) is for between about 30 seconds and about 210 minutes.

5. The process of claim 1 wherein the treating of step (c) is at a temperature of between about 110°

C. and about 150°

C., and for a time of between about 30 seconds and about two minutes.

6. The process of claim 1 wherein the lignocellulosic biomass hydrolysate fermentation broth of (a) or depleted broth of (b) attains a pH of about pH 6 or lower before or during treating of (c).

7. The process of claim 1 wherein passing through a filter of (d) is by vacuum filtration or pressure filtration.

8. The process of claim 1 wherein the target product is selected from the group consisting of acids, alcohols, alkanes, alkenes, aromatics, aldehydes, ketones, biopolymers, proteins, peptides, amino acids, vitamins, antibiotics, and pharmaceuticals.

9. The process of claim 8 wherein the target product is selected from the group consisting of ethanol, butanol and 1,3-propanediol.

10. The process of claim 1 wherein the target product is ethanol, and wherein the ethanol is removed from the lignocellulosic biomass hydrolysate fermentation broth in step (b) by distillation producing a depleted broth that is a whole stillage.

11. The process of claim 1 wherein the target product is butanol and wherein the butanol is removed from the lignocellulosic biomass hydrolysate fermentation broth in step (b) by solvent extraction producing a depleted broth.

12. The process of claim 1 wherein the lignocellulosic biomass hydrolysate fermentation broth is produced from biomass that is selected from the group consisting of switchgrass, waste paper, sludge from paper manufacture, corn cobs, corn husks, corn stover, grasses, wheat, wheat straw, hay, barley straw, rice straw, sugar cane bagasse, components obtained from processing of grains, trees, branches, roots, leaves, wood chips, sawdust, shrubs and bushes, vegetables, fruits, and flowers

13. The process of claim 1 wherein the liquid fraction of step (d) is recycled.