Production of fermentable sugars and lignin from biomass using supercritical fluids

• US 10,053,745 B2
• Filed: 05/03/2016
• Issued: 08/21/2018
• Est. Priority Date: 01/19/2010
• Status: Active Grant

• Current Assignee: Renmatix, Inc.
• Original Assignee: Renmatix, Inc.
• Inventors: Kilambi, Srinivas, Kadam, Kiran L.
• Primary Examiner(s): Mayes, Melvin C.
• Assistant Examiner(s): Cohen, Stefanie J
• Application Number:
  US15/145,043
• Publication Number:
  US 20160244852A1
• Time in Patent Office: 840 Days
• Field of Search: None
• CPC Class Codes: B29C 48/41 Intermeshing counter-rotating screws
• CPC Class Codes: B29C 48/535 with thread pitch varying along the longitudinal axis
• CPC Class Codes: C12P 7/10 substrate containing cellulosic material
• CPC Class Codes: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: C13K 13/00 Sugars not otherwise provided for in this class
• CPC Class Codes: C13K 13/002 Xylose
• CPC Class Codes: D21C 1/00 Pretreatment of the finely-divided materials before digesting of waste paper D21C5/02
• CPC Class Codes: D21C 11/0007 Recovery of by-products, i.e. compounds other than those necessary for pulping, for multiple uses or not otherwise provided for volatile compounds obtained by decomposition of spent liquors in order to regenerate them D21C11/125; compounds obtained by fractionating the liquors in order to regenerate them D21C11/0042
• CPC Class Codes: D21C 3/22 Other features of pulping processes
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02P 20/54 using solvents, e.g. supercritical solvents or ionic liquids

Abstract

Methods are disclosed for the continuous treatment of biomass comprising a pretreatment step, wherein said biomass is contacted with a first supercritical, near-critical, or sub-critical fluid to form a solid matrix and a first liquid fraction; and a hydrolysis step, wherein said solid matrix formed in said pretreatment step is contacted with a second supercritical or near-supercritical fluid to produce a second liquid fraction and an insoluble lignin-containing fraction. Also disclosed are apparatuses for the continuous conversion of biomass comprising a pretreatment reactor and a hydrolysis reactor associated with said pretreatment reactor.

Claims

1. A method of producing glucose from lignocellulosic biomass, comprising:

providing a biomass, comprising;

a first solid fraction comprising;

cellulose; and

insoluble lignin; and

a first liquid fraction;

mixing said solid fraction with water to form a slurry;

contacting said slurry with a second reaction fluid to form a reaction mixture comprising;

a second solid fraction comprising;

insoluble lignin; and

a second liquid fraction comprising;

a saccharide selected from the group consisting of cello-oligosaccharides, glucose, and mixtures thereof;

wherein said second reaction fluid comprises water and said second reaction fluid having a temperature and a pressure above the critical point of water; and

reducing the temperature of said reaction mixture to a temperature below the critical point of water.

2. The method of claim 1,

wherein said slurry is pre-heated to a temperature less than the critical point of water prior to said contacting step.

3. The method of claim 2,

wherein said pre-heating is carried out at a temperature of about 180°

C. to about 260°

C. and a pressure of about 200 bar to about 260 bar.

4. The method of claim 1,

wherein said contacting said slurry with a second reaction fluid is carried out in a hydrolysis step, and said hydrolysis step occurs at a temperature of about 275°

C. to about 450°

C.

5. The method of claim 1,

wherein the second liquid fraction comprises cello-oligosaccharides and the method further comprises hydrolyzing cello-oligosaccharides to form glucose.

6. The method of claim 5,

wherein said hydrolyzing comprises contacting said second liquid fraction with hot compressed water, or a third near-critical or sub-critical fluid, to produce a third liquid fraction comprising glucose monomers;

wherein said third near-critical or sub-critical fluid comprises water; and

optionally, wherein said hot compressed water or said third near-critical or sub-critical fluid comprises acid.

7. The method of claim 6,

wherein said acid is present in an amount of about 0.1% to about 1.5% by weight, based on the weight of said hot compressed water, or said third near-critical or sub-critical fluid, whichever is employed in said hydrolyzing said second liquid fraction.

8. The method of claim 6,

wherein said hydrolyzing employs said hot compressed water;

and

said hot compressed water has a temperature of about 50°

C. to about 250°

C. and a pressure sufficient to maintain said hot compressed water in a liquid state; and

further wherein said hot compressed water comprises acid.

9. The method of claim 1,

wherein said first liquid fraction comprises xylo-oligosaccharides,

wherein said first liquid fraction is contacted with a second hot compressed water, or a fourth near-critical or sub-critical fluid, to produce a fourth liquid fraction comprising xylose monomers;

wherein said fourth near-critical or sub-critical fluid comprises water; and

optionally, wherein said second hot compressed water or said fourth near-critical or sub-critical fluid comprises acid.

10. The method of claim 9,

wherein said acid is present in an amount of about 0.1% to about 1.5% by weight, based on the weight of said second hot compressed water, or said fourth near-critical or sub-critical fluid, whichever is employed.

11. The method of claim 9,

wherein said first liquid fraction is contacted with said second hot compressed water;

and

said second hot compressed water has a temperature of about 50°

C. to about 250°

C. and a pressure sufficient to maintain said second hot compressed water in a liquid state; and

further wherein said hot compressed water comprises acid.

12. The method of claim 1,

wherein said method is continuous.

13. The method of claim 1,

wherein said biomass is produced by subjecting lignocellulosic biomass to a supercritical, near-critical, or sub-critical fluid, and wherein said supercritical, near-critical, or sub-critical fluid comprises water.

14. The method of claim 1,

wherein said second reaction fluid further comprises carbon dioxide.

15. The method of claim 1,

wherein said first liquid fraction comprises xylo-oligosaccharides, and said method further comprises addition of acid to said first liquid fraction.

16. The method of claim 5,

wherein said hydrolyzing comprises addition of acid.