Processes for producing lignin-coated hydrophobic cellulose, and compositions and products produced therefrom

Patent metadata

Field	Value
Publication number	US-11142668-B2
Application number	US-201916663671-A
Country	US
Kind code	B2
Filing date	Oct 25, 2019
Priority date	Feb 18, 2014
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

Processes disclosed are capable of converting biomass into high-crystallinity, hydrophobic cellulose. In some variations, the process includes fractionating biomass with an acid (such as sulfur dioxide), a solvent (such as ethanol), and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; and depositing lignin onto cellulose fibers to produce lignin-coated cellulose materials (such as dissolving pulp). The crystallinity of the cellulose material may be 80% or higher, translating into good reinforcing properties for composites. Optionally, sugars derived from amorphous cellulose and hemicellulose may be separately fermented, such as to monomers for various polymers. These polymers may be combined with the hydrophobic cellulose to form completely renewable composites.

First claim

What is claimed is:

1. A process for producing a lignin-coated cellulose material, said process comprising:
(a) providing a lignocellulosic biomass feedstock;
(b) fractionating said feedstock in the presence of an acid, a solvent for lignin, and water, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin, wherein said feedstock, said acid, said solvent for lignin, and said water are all contained together in a digestor;
(c) depositing at least some of said lignin, from said liquid, onto a surface of said cellulose-rich solids to generate a lignin-coated cellulose material containing cellulose particles having a surface concentration of lignin that is greater than a bulk concentration of lignin;
(d) mechanically treating said lignin-coated cellulose material with a total mechanical energy of less than about 1000 kilowatt-hours per ton of said lignin-coated cellulose material, wherein said mechanically treating releases cellulose fibrils and/or cellulose crystals; and
(e) recovering said lignin-coated cellulose material,
wherein cellulose crystallinity of said lignin-coated cellulose material is at least 60%,
wherein said lignin-coated cellulose material is at least partially hydrophobic, and
wherein said lignin-coated cellulose material is lignin-coated microfibrillated cellulose or lignin-coated microcrystalline cellulose.

2. The process of claim 1 , wherein said acid is selected from the group consisting of sulfur dioxide, sulfurous acid, sulfur trioxide, sulfuric acid, lignosulfonic acid, and combinations thereof.

3. The process of claim 2 , wherein said acid is sulfur dioxide.

4. The process of claim 3 , wherein sulfur dioxide concentration in step (b) is from about 12 wt % to about 30 wt %.

5. The process of claim 1 , wherein fractionation temperature in step (b) is from about 140° C. to about 170° C.

6. The process of claim 1 , wherein fractionation time in step (b) is from about 1 hour to about 2 hours.

7. The process of claim 1 , wherein steps (c) and (d) are integrated.

8. The process of claim 1 , wherein said lignin-coated cellulose material is treated with a total mechanical energy of less than about 500 kilowatt-hours per ton of said lignin-coated cellulose material.

9. The process of claim 1 , wherein said process further comprises treatment of said lignin-coated cellulose material with one or more enzymes.

10. The process of claim 1 , wherein said process further comprises treatment of said lignin-coated cellulose material with one or more acids.

11. The process of claim 10 , wherein said one or more acids are selected from the group consisting of sulfur dioxide, sulfurous acid, lignosulfonic acid, acetic acid, formic acid, and combinations thereof.

12. The process of claim 1 , wherein said process further comprises treatment of said lignin-coated cellulose material with heat.

13. The process of claim 1 , wherein said cellulose crystallinity of said lignin-coated cellulose material is at least 70%.

14. The process of claim 13 , wherein said cellulose crystallinity of said lignin-coated cellulose material is at least 80%.

15. The process of claim 1 , said process further comprising chemically converting said lignin-coated cellulose material to one or more lignin-coated cellulose derivatives.

16. The process of claim 15 , wherein said lignin-coated cellulose derivatives are selected from the group consisting of cellulose esters, cellulose ethers, cellulose ether esters, alkylated cellulose compounds, cross-linked cellulose compounds, acid-functionalized cellulose compounds, base-functionalized cellulose compounds, and combinations thereof.

Assignees

• Granbio Intellectual Property Holdings Llc

Inventors

• Nelson Kimberly
• Retsina Theodora
• Pylkkanen Vesa
• O'Connor Ryan

Classifications

• C08L97/02

  Lignocellulosic material, e.g. wood, straw or bagasse {(manufacture of articles made from lignocellulosic material by dry processes B27N)} · CPC title

• C09K2208/08

  Fiber-containing well treatment fluids · CPC title

• C12P2203/00

  Fermentation products obtained from optionally pretreated or hydrolyzed cellulosic or lignocellulosic material as the carbon source · CPC title

• D21H19/52

  Cellulose; Derivatives thereof · CPC title

• C08L5/14

  Hemicellulose; Derivatives thereof · CPC title