Clean sugar and lignin from non-chemically pretreated lignocellulosic biomass

Patent metadata

Field	Value
Publication number	US-10072228-B2
Application number	US-201313868964-A
Country	US
Kind code	B2
Filing date	Apr 23, 2013
Priority date	Apr 23, 2013
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

Methods of producing clean (e.g., low sulfur and metal ion content, and free of fermentation inhibitors) sugar and lignin-rich streams, and downstream conversion products, from lignocellulosic biomass, may include obtaining non-chemically pretreated, milled lignocellulosic biomass, reacting the milled lignocellulosic biomass with an enzymatic agent to produce a slurry that includes converted monomeric lignocellulosic sugars and lignin-rich residuals, and separating the slurry into a sugar stream that includes the converted monomeric lignocellulosic sugars and a lignin-rich stream that includes the lignin-rich residuals. The sugar stream, not including water, includes at least 75% monomeric lignocellulosic sugar, less than 0.20% sulfur, and less than 3.0% metal ion content, and the lignin-rich stream includes at least 35% lignin and less than 0.50% sulfur. Some methods include producing fermentation products such as alcohols and/or organic acids from the sugar stream, and/or use of the lignin residuals in fuels.

First claim

What is claimed is:

1. A method of lignocellulosic biomass conversion, the method comprising:
obtaining non-chemically pretreated, milled softwood lignocellulosic biomass having a particle size greater than 10 microns and less than 300 microns, wherein the softwood lignocellulosic biomass is from Douglas fir;
reacting the milled softwood lignocellulosic biomass with an enzymatic agent to produce a slurry that includes converted monomeric lignocellulosic sugars and lignin-rich residuals and is free of furans and other fermentation inhibitors; and
separating the slurry into a sugar composition that includes the converted monomeric lignocellulosic sugars and a lignin-rich composition that includes the lignin-rich residuals;
wherein the sugar composition, not including water, includes at least 75% monomeric lignocellulosic sugar, less than 0.20% sulfur, less than 3.0% metal ion content, and has:
a ratio of monomeric glucose plus monomeric mannose to monomeric xylose greater than 23.4,
a ratio of monomeric glucose plus monomeric mannose to monomeric galactose greater than 93.6, and/or
a ratio of monomeric glucose plus monomeric mannose to monomeric arabinose greater than 280.7; and

wherein the lignin-rich composition includes at least 35% lignin and less than 0.50% sulfur.

2. The method of claim 1 , wherein separating the slurry includes filtering the slurry to yield a filtrate that includes the sugar composition, and a high solid stream that includes the lignin-rich composition and undigested lignocellulosic biomass.

3. The method of claim 1 , further comprising, subsequent to separating the slurry, concentrating the sugar composition to produce a concentrated lignocellulosic sugar mixture.

4. The method of claim 1 , further comprising, subsequent to separating the slurry, drying the lignin-rich composition to produce a lignin composition having a solid content of at least 80%.

5. The method of claim 1 , wherein the composition of the sugar composition, not including water, includes at least 85.0% (w/w) monomeric lignocellulosic sugar.

6. The method of claim 1 , wherein the composition of the sugar composition, not including water, includes at least 90.0% (w/w) monomeric lignocellulosic sugar.

7. The method of claim 1 , further comprising producing a fermentation product from the converted monomeric lignocellulosic sugars in the sugar composition.

8. The method of claim 7 , wherein the fermentation product includes one or more of an alcohol and an organic acid.

9. The method of claim 1 , wherein the particle size of the non-chemically pretreated, milled lignocellulosic biomass is greater than 25 microns and less than 300 microns.

10. The method of claim 1 , wherein the Douglas fir is debarked.

11. A method of hydrolytic lignocellulosic biomass conversion, the method comprising:
in a first hydrolysis reaction, reacting non-chemically pretreated, milled softwood lignocellulosic biomass, the milled lignocellulosic biomass having a particle size greater than 10 microns and less than 300 microns, wherein the softwood lignocellulosic biomass is from Douglas fir, with an enzymatic agent to produce a first slurry that includes converted lignocellulosic sugars, lignin-rich residuals, and unused enzymatic agent;
mixing additional non-chemically pretreated, milled softwood lignocellulosic biomass with the first slurry to produce a slurry mixture;
separating the converted lignocellulosic sugars from the slurry mixture;
in a second hydrolysis reaction, reacting the non-chemically pretreated, milled softwood lignocellulosic biomass in the slurry mixture with the unused enzymatic agent in the slurry mixture to produce a second slurry that includes converted lignocellulosic sugars and lignin-rich residuals; and
separating the converted lignocellulosic sugars from the second slurry;
wherein the converted lignocellulosic sugars separated from the slurry mixture and/or the second slurry provide a sugar composition that has:
a ratio of monomeric glucose plus monomeric mannose to monomeric xylose greater than 23.4,
a ratio of monomeric glucose plus monomeric mannose to monomeric galactose greater than 93.6, and/or
a ratio of monomeric glucose plus monomeric mannose to monomeric arabinose greater than 280.7.

12. The method of claim 11 ,
wherein the first hydrolysis reaction is carried out in a hydrolysis unit;
wherein the separating is carried out in a filtration unit; and
wherein the mixing is carried out while transporting the slurry mixture from the hydrolysis unit to the filtration unit.

13. The method of claim 11 , further including one or more of:
combining the converted lignocellulosic sugars separated from the first and second slurries, and
combining the lignin-rich residuals from the first and second slurries.

14. A method of lignocellulosic biomass conversion, comprising:
obtaining non-chemically pretreated, milled softwood lignocellulosic biomass having a particle size greater than 10 microns and less than 300 microns, wherein the softwood lignocellulosic biomass is from Douglas fir;
reacting the milled lignocellulosic biomass with an enzymatic agent to produce a slurry that includes converted monomeric lignocellulosic sugars and lignin-rich residuals, wherein the slurry is free of furans and other fermentation inhibitors; and
separating the slurry into a sugar composition that includes the converted monomeric lignocellulosic sugars and a lignin-rich composition that includes the lignin-rich residuals;
wherein the sugar composition, not including water, includes at least 75% monomeric lignocellulosic sugar, less than 0.20% sulfur, less than 3.0% metal ion content, and has a monomeric glucose content that is greater than or equal to 78.8% of a total monomeric sugar content of the group consisting of glucose, mannose, arabinose, galactose, and xylose; and
wherein the lignin-rich composition includes at least 35% lignin and less than 0.50% sulfur.

15. The method of claim 14 , wherein the Douglas fir is debarked.

Assignees

• Int Paper Co

Inventors

• Gao Johnway
• Neogi Amar N

Classifications

• C10L5/363

  Pellets or granulates · CPC title

• C10L1/023

  for spark ignition · CPC title

• C08H8/00

  Macromolecular compounds derived from lignocellulosic materials {(pretreatment thereof B27N)} · CPC title

• C12P19/02

  Monosaccharides (2-ketogulonic acid C12P7/60) · CPC title

• Y02E50/10

  Biofuels, e.g. bio-diesel · CPC title