CONVERSION METHOD

• US 20090198046A1
• Filed: 05/18/2007
• Published: 08/06/2009
• Est. Priority Date: 05/25/2006
• Status: Active Grant

• Current Assignee: Petroliam Nasional Berhad (Government of Malaysia)
• Original Assignee: Petroliam Nasional Berhad (Government of Malaysia)
• Inventors: Fanselow, Markus, Holbrey, John, Seddon, Kenneth Richard
• Granted Patent: US 8,637,660 B2
• Time in Patent Office: Days
• US Class Current: 536/1.11
• CPC Class Codes: C08B 1/003 Preparation of cellulose solutions, i.e. dopes, with different possible solvents, e.g. ionic liquids solutions used in the manufacture of monocomponent artificial filaments or cellulose or derivatives thereof D01F2/02
• CPC Class Codes: C08B 15/00 Preparation of other cellulose derivatives or modified cellulose , e.g. complexes
• CPC Class Codes: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y10T 428/31772 Next to cellulosic
• CPC Class Codes: Y10T 428/31971 Of carbohydrate

Abstract

A process for the preparation of water-soluble cellulose hydrolysis products, which comprises admixing cellulose with an ionic liquid in which the cellulose has at least some sollubility, said ionic liquid state at a temperature at or below 150 -C, and treating the resulting solution with an acid in the presence of water, said acid having a pKa in water of less than 2 at 25 -C.

Claims

1. A process for the preparation of water-soluble cellulose hydrolysis products, the process comprising

admixing cellulose with an ionic liquid capable of solvating or dissolving at least some of the cellulose, wherein the ionic liquid is a compound comprised solely of cations and anions, and is a liquid at a temperature of 150°

C. or below, wherein the anions are selected from the group consisting of halide and cyanate; and

reacting the resulting solvate or solution with an acid in the presence of water, said acid having a pKa in water of less than 2 at 25°

C.

2. The process of claim 1, wherein said ionic liquid is capable of dissolving at least some of the cellulose.

3. The process of claim 1, wherein the acid has a pKa in water of 0 or less at 25°

C.

4. The process of claim 1, wherein the acid is selected from the group consisting of hydrogen halides, sulfuric acid, nitric acid, halosulfonic acids, tetrafluoroboric acid, heteropolyacids, aryl- and alkyl-sulfonic acids, and halogenated alkyl- and arylsulfonic acids.

5. The process of claim 4, wherein the acid is p-toluenesulfonic acid, trifluoromethanesulfonic acid, trichloromethanesulfonic acid, hydrochloric acid, hydrobromic acid, hydriodic acid, tetrafluoroboric acid, or sulfuric acid.

6. The process of claim 5, wherein the acid is sulfuric acid or hydrochloric acid.

7. The process of claim 1, wherein the reaction with the acid is carried out at a temperature in the range of from 50 to 200°

C.

8. The process claim 1, wherein the cation of the ionic liquid is selected from the group consisting of pyridinium, pyridazinium, pyrimidinium, pyrazinium, imidazoliuni, pyrazolium, oxazolium, triazolium, thiazolium, piperidinium, pyrrolidinium, quinolinium and isoquinolinium.

9. The process of claim 8, wherein the cation of the ionic liquid has a structure selected from the group consisting of:

wherein R¹ and R² are independently a C₁-C₆ alkyl group or a C₁-C₆ alkoxyalkyl group, and R³, R⁴, R⁵, R⁶, R⁷, R⁸ and R⁹ (R³-R⁹), when present, are independently selected from the group consisting of hydrido, C₁-C₆ alkyl, C₁-C₆ alkoxyalkyl and C₁-C₆ alkoxy.

10. The process of claim 9, wherein both R¹ and R² are C₁-C₆ alkyl, and R³-R⁹, when present, are hydrido.

11. The process of claim 9, wherein the cation of the ionic liquid is an imidazolium cation or a pyridinium cation.

12. The process of claim 11, wherein R³-R⁷ are each hydrido.

13. The process of claim 12, wherein the cation is a 1-methyl-3-C_1-6alkylimidazolium or a 1-C_1-6alkylpyridiniium cation.

14. The process claim 1, wherein the anion is a halide.

15. The process of claim 14, wherein the anion is chloride.

16. The process claim 1, wherein the cellulose is admixed with the ionic liquid in an amount of from 5 to 35% weight.

17. The process claim 1, wherein water is present in the reaction system in a weight ratio of water to cellulose from 1:

1 to 1;

20.

18. The process of claim 17, wherein the weight ratio of water to cellulose is from 1:

5 to 1;

15.

19. A process for the preparation of one or more alcohols, which comprises carrying out the process of claim 1, and converting at least part of the resulting product into one or more alcohols.