Solvent-based processes for producing nanocellulose, and compositions and products produced therefrom

Patent metadata

Field	Value
Publication number	US-2018016355-A1
Application number	US-201715644878-A
Country	US
Kind code	A1
Filing date	Jul 10, 2017
Priority date	Jul 14, 2016
Publication date	Jan 18, 2018
Grant date	—

Abstract

The present invention provides a process for producing a nanocellulose material, comprising: fractionating a lignocellulosic biomass feedstock in the presence of a solvent for lignin and water, but no acid catalyst, to generate cellulose-rich solids; and then mechanically treating the cellulose-rich solids to form a nanocellulose material comprising cellulose nanofibrils and/or cellulose nanocrystals. Many organic or inorganic solvents are possible. In some embodiments, the solvent for lignin is an oxygenated organic compound, such as a C 1 -C 18 alcohol, e.g. ethanol, ethylene glycol, propanol, propanediol, glycerol, butanol, or butanediol. The solvent for lignin may be an aromatic alcohol, such as phenol, cresol, or benzyl alcohol. The solvent for lignin may be a ketone, an aldehyde, or an ether, such as methyl ethyl ketone or diethyl ether. The solvent for lignin may be a non-oxygenated alkane, olefin, or aromatic hydrocarbon. In some embodiments, the solvent for lignin is an ionic liquid.

First claim

What is claimed is:

1 . A process for producing a nanocellulose material, said process comprising:
(a) providing a lignocellulosic biomass feedstock; (b) fractionating said feedstock in the presence of a solvent for lignin and water, but no acid catalyst, to generate cellulose-rich solids and a liquid containing hemicellulose and lignin; (c) mechanically treating said cellulose-rich solids to form a nanocellulose material comprising cellulose nanofibrils and/or cellulose nanocrystals, and (d) recovering said nanocellulose material.

2 . The process of claim 1 , wherein said solvent for lignin is an oxygenated organic compound.

3 . The process of claim 2 , wherein said solvent for lignin is an aliphatic alcohol.

4 . The process of claim 2 , wherein said solvent for lignin is an aromatic alcohol.

5 . The process of claim 2 , wherein said solvent for lignin is a ketone, an aldehyde, an ether, or a combination thereof.

6 . The process of claim 1 , wherein said solvent for lignin is a non-oxygenated alkane, non-oxygenated olefin, non-oxygenated aromatic hydrocarbon, or a combination thereof.

7 . The process of claim 1 , wherein said solvent for lignin is an ionic liquid.

8 . The process of claim 1 , wherein said solvent for lignin is water-soluble and, during step (b), forms a single phase with said water.

9 . The process of claim 1 , wherein said solvent for lignin, during step (b), forms a separate phase from said water or from a water-rich phase comprising said water.

10 . The process of claim 1 , wherein step (c) further comprises treatment of said cellulose-rich solids 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 step (c) further comprises treatment of said cellulose-rich solids with one or more enzymes.

13 . The process of claim 1 , said process further comprising bleaching said cellulose-rich solids prior to step (c) and/or as part of step (c).

14 . The process of claim 1 , said process further comprising bleaching said nanocellulose material during step (c) and/or following step (c).

15 . The process of claim 1 , wherein during step (c), said cellulose-rich solids are treated with a total mechanical energy of less than about 5000 kilowatt-hours per ton of said cellulose-rich solids.

16 . The process of claim 1 , wherein said crystallinity of said nanocellulose material is at least 60%.

17 . The process of claim 1 , said process further comprising hydrolyzing amorphous cellulose into glucose in step (b) and/or step (c), recovering said glucose, and optionally fermenting said glucose to a fermentation product.

18 . The process of claim 1 , said process further comprising recovering, fermenting, or further treating hemicellulosic sugars derived from said hemicellulose.

19 . The process of claim 18 , said process further comprising fermenting said hemicellulosic sugars to produce a monomer or precursor thereof; polymerizing said monomer to produce a polymer; and combining said polymer and said nanocellulose material to form a polymer-nanocellulose composite.

20 . The process of claim 1 , wherein said nanocellulose material is at least partially hydrophobic via deposition of at least some of said lignin onto a surface of said cellulose-rich solids during step (b), or via deposition of at least some of said lignin onto a surface of said nanocellulose material during step (c) or step (d).

Assignees

• Api Ip Holdings Llc

Inventors

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

Classifications

• C12P7/10

  substrate containing cellulosic material · CPC title

• C12P19/02

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

• D21C3/20

  with organic solvents {or in solvent environment} · CPC title

• D21H11/18

  Highly hydrated, swollen or fibrillatable fibres · CPC title

• C08B15/08 Primary

  Fractionation of cellulose, e.g. separation of cellulose crystallites · CPC title