Conversion of sugars to ionic liquids

Patent metadata

Field	Value
Publication number	US-10934568-B2
Application number	US-201716308440-A
Country	US
Kind code	B2
Filing date	Jun 7, 2017
Priority date	Jun 7, 2016
Publication date	Mar 2, 2021
Grant date	Mar 2, 2021

Abstract

Disclosed herein are methods for preparing sugar compositions. The methods include: i) forming a mixture including polysaccharide biomass and an ionic liquid solution, wherein the ionic liquid solution contains water and an ionic liquid, and the ionic liquid contains a) a cation and b) a sugar acid anion or a ketoacid anion; ii) maintaining the mixture under conditions sufficient to dissolve at least a portion of the polysaccharide present in the polysaccharide biomass; iii) adding at least one glycoside hydrolase to the mixture; and iv) maintaining the mixture containing the glycoside hydrolase under conditions sufficient to hydrolyze at least a portion of the dissolved polysaccharide, thereby forming the sugar compositions. The sugar compositions contain at least one monosaccharide or oligosaccharide. New sugar-based ionic liquids are also described.

First claim

What is claimed is:

1. A method for preparing a sugar composition, the method comprising:
i) forming a mixture comprising polysaccharide biomass and an ionic liquid solution, wherein
the ionic liquid solution comprises water and an ionic liquid, and the ionic liquid comprises a) a cation and b) an anion, wherein the anion is selected from the group consisting of a mucic acid anion, a saccharic acid anion, a xylaric acid anion, an arabinaric acid anion, a mannaric acid anion, an α-ketoglutaric acid anion, and a levulinic acid anion;

ii) maintaining the mixture under conditions sufficient to dissolve at least a portion of the polysaccharide present in the polysaccharide biomass;
iii) adding at least one glycoside hydrolase to the mixture; and
iv) maintaining the mixture containing the glycoside hydrolase under conditions sufficient to hydrolyze at least a portion of the dissolved polysaccharide, thereby forming the sugar composition;
wherein the sugar composition comprises at least one monosaccharide or oligosaccharide.

2. The method of claim 1 , wherein the anion is selected from the group consisting of a mucic acid anion, a saccharic acid anion, a xylaric acid anion, an arabinaric acid anion, and a mannaric acid anion.

3. The method of claim 1 , wherein the anion is selected from the group consisting of an α-ketoglutaric acid anion, and a levulinic acid anion.

4. The method of claim 1 , wherein the anion is selected from the group consisting of a mucic acid anion and an α-ketoglutaric acid anion, wherein the mucic acid anion is a mucic acid dianion, and wherein the α-ketoglutaric acid anion is an α-ketoglutaric acid dianion.

5. The method of claim 1 , wherein the cation is selected from the group consisting of choline, (C 1-18 alkyl) 3 NH + , (C 1-6 alkyl) x (C 6-18 alkyl) y N + , (C 1-10 alkyl) z imidazol-ium, (C 1-10 alkyl) z pyrazolium, and mixtures thereof; wherein subscript x and subscript y are each 0, 1, 2, 3, or 4, and the sum of x and y is 4; and wherein each subscript z is 1, 2, or 3.

6. The method of claim 1 , wherein the ionic liquid solution comprises from about 25% (w/w) to about 95% (w/w) water.

7. The method of claim 1 , wherein the mixture in step i) comprises from about 5% (w/w) to about 30% (w/w) polysaccharide biomass.

8. The method of claim 1 , wherein step ii) comprises maintaining the mixture of step i) at a temperature of at least about 100° C. for at least about 30 minutes.

9. The method of claim 1 , wherein the pH of the mixture in step i) is greater than 7.

10. The method of claim 9 , further comprising:
ii-b) reducing the pH of the mixture containing the dissolved polysaccharide to less than 7 prior to adding the glycoside hydrolase in step iii).

11. The method of claim 10 , wherein step ii-b) comprises adding an acid to the mixture resulting from step ii).

12. The method of claim 11 , wherein the acid used in step ii-b) is the same sugar acid or ketoacid used in step i).

13. The method of claim 1 , wherein the polysaccharide biomass comprises cellulose, hemicellulose, lignocellulose, or mixtures thereof.

14. The method claim 1 , wherein the glycoside hydrolase is a cellulase, an endoglucanase, an exoglucanase, a β-glucosidase, a xylanase, or a mixture thereof.

Assignees

• Nat Tech & Eng Solutions Sandia Llc

Inventors

• Gladden John M
• Dutta Tanmoy
• Sun Jian
• Singh Seema
• Simmons Blake A

Classifications

• C12P2201/00

  Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis · CPC title

• C12Y302/01021

  Beta-glucosidase (3.2.1.21) · CPC title

• C07H1/00

  Processes for the preparation of sugar derivatives · CPC title

• C12P19/02

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

• C07H3/02

  Monosaccharides · CPC title