Production of fermentable sugars and lignin from biomass using supercritical fluids

Patent metadata

Field	Value
Publication number	US-10053745-B2
Application number	US-201615145043-A
Country	US
Kind code	B2
Filing date	May 3, 2016
Priority date	Jan 19, 2010
Publication date	Aug 21, 2018
Grant date	Aug 21, 2018

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.

First claim

What is claimed is:

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.

Assignees

• Renmatix Inc

Inventors

• Kilambi Srinivas
• Kadam Kiran L

Classifications

• C12P7/10

  substrate containing cellulosic material · CPC title

• C13K1/02 Primary

  obtained by saccharification of cellulosic materials (manufacture of fodder A23K10/32) · CPC title

• D21C11/0007

  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 title

• C13K13/002

  Xylose · CPC title

• D21C3/22

  Other features of pulping processes · CPC title