Oxygen assisted organosolv process, system and method for delignification of lignocellulosic materials and lignin recovery

• US 9,382,283 B2
• Filed: 08/01/2014
• Issued: 07/05/2016
• Est. Priority Date: 08/01/2014
• Status: Active Grant

• Current Assignee: Agency For Science Technology and Research
• Original Assignee: Agency For Science Technology and Research
• Inventors: Manesh, Ali, Guenther, John H., Zoborowski, Edwin G., Braenner, Walter, Manesh, Mohammad Ali, Hawk, Lee J.
• Primary Examiner(s): Salvitti, Michael A
• Application Number:
  US14/449,812
• Publication Number:
  US 20160031921A1
• Time in Patent Office: 704 Days
• US Class Current: 1/1
• CPC Class Codes: C07G 1/00 Lignin; Lignin derivatives
• CPC Class Codes: C08H 6/00 Macromolecular compounds derived from lignin, e.g. tannins, humic acids
• CPC Class Codes: C08H 8/00 Macromolecular compounds derived from lignocellulosic materials pretreatment thereof B27N
• CPC Class Codes: C08L 97/005 Lignin
• CPC Class Codes: D21C 1/00 Pretreatment of the finely-divided materials before digesting of waste paper D21C5/02
• CPC Class Codes: D21C 3/00 Pulping cellulose-containing materials digesters D21C7/00

Abstract

An oxygen assisted Organosolv process for a more efficient delignification and producing bio-products by decomposing lignocellulosic materials comprises providing a lignin solvent with water, an acid, an oxidant and one or more lignin dissolving chemicals. The process also includes placing biomass in contact with oxidant, acid, water, the lignin solvent in any order or combined to form a recyclable solvent, and recycling at least a portion of the recyclable solvent by circulating the recyclable solvent back into contact with the biomass. The circulating of the recyclable solvent occurs for a period of time, during which, acid and oxidant may be added if necessary as they may be consumed by the process, after which, the process then includes separating material such as chemicals and lignin from the recyclable solvent. The chemicals can be recycled as new lignin dissolving solvent or sold, while lignin can be used as natural and renewable colorant for polymers such as poly lactic acid, or mixed with other polymers as an additive and extruded or injected to consumable polymeric parts, or can be used and the natural source of renewable aromatics. Application of an oxidant will help the overall fractionation process by changing the chemical characteristics of the lignin and therefore allows more lignin to be removed from biomass. At the end, the lignin is separated from the lignin dissolving solvent by a separation process to also reclaim the lignin dissolving solvent for the next fractionation process.

Claims

1. An oxidizing-agent assisted organosolv based fractionation process for delignification of lignocellulosic biomass materials comprising:

a) reacting organic solvent, oxidant, acid, water, and lignocellulosic biomass with heat to form an insoluble phase and a soluble phase, the insoluble phase comprising delignified biomass and the soluble phase comprising a lignin enriched solution;

b) separating the soluble phase from the insoluble phase;

c) separating the soluble phase into an organic phase and an aqueous phase;

d) recovering a recyclable solvent mixture from the organic phase such that the remaining products comprises lignin; and

e) reacting the recyclable solvent mixture and additional oxidant, additional acid, additional water, and additional lignocellulosic biomass with heat to form an insoluble phase and soluble phase.

2. The process of claim 1 wherein the organic solvent comprises butanol.

3. The process of claim 1 wherein the oxidant comprises hydrogen peroxide.

4. The process of claim 1 wherein the acid comprises sulfuric acid.

5. The process of claim 1 wherein the ratio of water to organic solvent is about 1:

1 by weight.

6. The process of claim 1 wherein recovering the recyclable solvent mixture comprises applying heat to the organic phase to evaporate the recyclable solvent mixture, condensing the evaporated recyclable solvent mixture back into a liquid and collecting the condensed liquid.

7. The process of claim 1 wherein between about 5 grams and about 15 grams of organic solvent is provided per 1 gram of biomass.

8. The process of claim 1 wherein the additional water comprises the aqueous phase.

9. The process of claim 1 wherein up to about 0.6 grams of oxidant is provided per 1 gram of the lignocellulosic biomass.

10. An oxidizing-agent assisted organosolv based fractionation process for delignification of lignocellulosic biomass materials comprising:

a) reacting organic solvent, gaseous O₂, acid, water, and lignocellulosic biomass with heat to form an insoluble phase and a soluble phase, the insoluble phase comprising delignified biomass and the soluble phase comprising a lignin enriched solution;

b) separating the soluble phase from the insoluble phase;

c) separating the soluble phase into an organic phase and an aqueous phase;

d) recovering a recyclable solvent mixture from the organic phase such that the remaining products comprises lignin; and

e) reacting the recyclable solvent mixture and additional gaseous O₂, additional acid, additional water, and additional lignocellulosic biomass with heat to form an insoluble phase and soluble phase.

11. The process of claim 10 wherein the organic solvent comprises butanol.

12. The process of claim 10 wherein the acid comprises sulfuric acid.

13. The process of claim 10 wherein the ratio of water to organic solvent is about 1:

1 by weight.

14. The process of claim 10 wherein recovering the recyclable solvent mixture comprises applying heat to the organic phase to evaporate the recyclable solvent mixture, condensing the evaporated recyclable solvent mixture back into a liquid and collecting the condensed liquid.

15. The process of claim 10 wherein between about 5 grams and about 15 grams of organic solvent is provided per 1 gram of biomass.

16. The process of claim 10 wherein the additional water comprises the aqueous phase.

17. The process of claim 10 wherein up to about 0.6 grams of oxidant is provided per 1 gram of the lignocellulosic biomass.

18. An oxidizing-agent assisted organosolv based fractionation process for delignification of lignocellulosic biomass materials comprising:

a) reacting organic solvent, oxidant, acid, water, and lignocellulosic biomass with heat to form an insoluble phase and a soluble phase, the insoluble phase comprising delignified biomass and the soluble phase comprising a lignin enriched solution;

b) separating the soluble phase from the insoluble phase;

c) separating the soluble phase into an organic phase and an aqueous phase; and

d) reacting the organic phase and additional oxidant, additional acid, additional water, and additional lignocellulosic biomass with heat to form an insoluble phase and soluble phase.

19. The process of claim 18 wherein the oxidant is hydrogen peroxide.

20. The process of claim 18 wherein the organic solvent comprises butanol.

21. The process of claim 18 wherein the acid comprises sulfuric acid.

22. The process of claim 18 wherein the ratio of water to organic solvent is about 1:

1 by weight.

23. The process of claim 18 wherein between about 5 grams and about 15 grams of organic solvent is provided per 1 gram of biomass.

24. The process of claim 18 wherein the organic phase comprises between about 5% and about 25% lignin by weight.

25. The process of claim 18 wherein the additional water comprises the aqueous phase.

26. The process of claim 18 wherein up to about 0.6 grams of oxidant is provided per 1 gram of the lignocellulosic biomass.

27. An oxidizing-agent assisted organosolv based fractionation process for delignification of lignocellulosic biomass materials comprising:

a) reacting organic solvent, gaseous O₂, acid, water, and lignocellulosic biomass with heat to form an insoluble phase and a soluble phase, the insoluble phase comprising delignified biomass and the soluble phase comprising a lignin enriched solution;

b) separating the soluble phase from the insoluble phase;

c) separating the soluble phase into an organic phase and an aqueous phase; and

d) reacting the organic phase and additional gaseous O₂, additional acid, additional water, and additional lignocellulosic biomass with heat to form an insoluble phase and soluble phase.

28. The process of claim 27 wherein the organic solvent comprises butanol.

29. The process of claim 27 wherein the acid comprises sulfuric acid.

30. The process of claim 27 wherein the ratio of water to organic solvent is about 1:

1 by weight.

31. The process of claim 27 wherein between about 5 grams and about 15 grams of organic solvent is provided per 1 gram of biomass.

32. The process of claim 27 wherein the organic phase comprises between about 5% and about 25% lignin by weight.

33. The process of claim 27 wherein the additional water comprises the aqueous phase.

34. The process of claim 27 wherein up to about 0.6 grams of oxidant is provided per 1 gram of the lignocellulosic biomass.