METHODS FOR PRETREATING BIOMASS

• US 20110192559A1
• Filed: 12/22/2010
• Published: 08/11/2011
• Est. Priority Date: 05/01/2006
• Status: Active Grant

• Current Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Original Assignee: The Board of Trustees of Michigan State University (Michigan State University)
• Inventors: Sousa, Leonardo, Chundawat, Shishir, Venkatesh, Balan, Dale, Bruce E.
• Granted Patent: US 8,968,515 B2
• Time in Patent Office: Days
• US Class Current: 162/29
• 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: C12P 19/02 Monosaccharides 2-ketogulonic acid C12P7/60
• CPC Class Codes: C12P 19/14 produced by the action of a carbohydrase (EC 3.2.x), e.g. by alpha-amylase , e.g. by cellulase, hemicellulase
• CPC Class Codes: C12P 2201/00 Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis
• CPC Class Codes: C12P 7/10 substrate containing cellulosic material
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02P 30/20 using bio-feedstock

Abstract

A method of alkaline pretreatment of biomass, in particular, pretreating biomass with gaseous ammonia.

Claims

1. A method for treating biomass comprising:

delivering gaseous ammonia at an elevated temperature to a reaction vessel containing biomass;

and

allowing the gaseous ammonia to condense on the biomass and react with water present in the biomass, wherein reactivity of plant polymers in the biomass is increased as a result.

2. The method of claim 30 wherein the reaction vessel temperature is between about 50 degrees Celsius and about 200 degrees Celsius.

3. The method of claim 30 wherein the reaction vessel temperature is between about 50 degrees Celsius and about 100 degrees Celsius.

5. The method of claim 1 wherein the gaseous ammonia is delivered to the reaction vessel at a pressure between about 100 psi and about 1000 psi.

7. The method of claim 5 wherein the gaseous ammonia is delivered to the reaction vessel at a pressure between about 100 psi and about 300 psi.

9. The method of claim 1 wherein the biomass is comprised of about 5% to about 233% water on a dry weight basis.

10. The method of claim 1 wherein the biomass is comprised of from about 5% to about 60% water on a dry weight basis.

12. The method of claim 1 wherein the gaseous ammonia reacts with the water in the biomass for about 1 minute to about 36 hours.

14. The method of claim 12 wherein the gaseous ammonia reacts with the water in the biomass for about 1 minute to about 120 minutes.

15. The method of claim 1 wherein the biomass is substantially uniformly pretreated by the gaseous ammonia.

16. The method of claim 1 wherein the method is a is continuous method.

17. The method of claim 1 further comprising delivering a carrier to the reaction vessel.

18. The method of claim 17 wherein the carrier is combined with the gaseous ammonia.

19. The method of claim 18 wherein the carrier and the gaseous ammonia are combined before the gaseous ammonia is delivered to the reaction vessel.

20. The method of claim 18 wherein the carrier and the gaseous ammonia are combined after the gaseous ammonia is delivered to the reaction vessel.

21. The method of claim 17 wherein the carrier is oxidative.

22. The method of claim 21 wherein the carrier is air.

23. The method of claim 17 wherein the carrier is an inert gas.

24. The method of claim 17 wherein the carrier is steam.

25. The method of claim 1 wherein the reaction vessel is a fluidized bed reactor.

26. The method of claim 1 further comprising recycling at least a portion of the gaseous ammonia.

28. The method of claim 1 wherein the plant polymers include hemicelluloses and cellulose.

29. The method of claim 1 wherein at least a portion of the water present in the biomass is added water.

30. The method of claim 1 wherein the reaction vessel has a reaction vessel temperature which increases substantially instantaneously when the water and gaseous ammonia react.

31. The method of claim 1 wherein the method is a semi-batch method.

32. The method of claim 23 wherein the inert gas is nitrogen.

33. The method of claim 1 wherein the reaction vessel is a fixed bed reactor or a semi-fluidized bed reactor.

4. (canceled)

6. (canceled)

8. (canceled)

11. (canceled)

13. (canceled)

27. A method for treating biomass comprising:

in a reaction vessel, impregnating biomass with an amount of ammonia;

delivering a gaseous carrier at an elevated temperature to the reaction vessel; and

allowing the gaseous carrier to react with water present in the biomass, wherein the amount of ammonia utilized is reduced as compared to reacting the ammonia and water without the gaseous carrier.

34. The method of claim 27 further comprising removing the biomass from the reaction vessel.