OZONE TREATMENT OF BIOMASS TO ENHANCE ENZYMATIC SACCHARIFICATION

• US 20100159521A1
• Filed: 12/17/2009
• Published: 06/24/2010
• Est. Priority Date: 12/19/2008
• Status: Abandoned Application

• Current Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Original Assignee: E. I. du Pont de Nemours and Company (Corteva, Inc.)
• Inventors: Diner, Bruce A., Cirakovic, Jelena
• Application Number:
  US12/640,088
• Publication Number:
  US 20100159521A1
• Time in Patent Office: Days
• US Class Current: 435/72
• CPC Class Codes: C08H 8/00 Macromolecular compounds derived from lignocellulosic materials pretreatment thereof B27N
• CPC Class Codes: C10G 2300/1011 Biomass
• CPC Class Codes: C10L 1/02 essentially based on components consisting of carbon, hydrogen, and oxygen only
• 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: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: D21C 3/024 with NH3 or H2O
• CPC Class Codes: D21C 3/028 in presence of O3
• CPC Class Codes: D21C 3/20 with organic solvents or in solvent environment
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel
• CPC Class Codes: Y02P 30/20 using bio-feedstock

Abstract

Methods for treating lignocellulosic biomass to produce readily saccharifiable carbohydrate-enriched biomass are provided. In one method, lignocellulosic biomass comprising lignin is treated with aqueous ammonia, then contacted with a gas comprising ozone at a temperature of about 0° C. to about 50° C. In another method, lignocellulosic biomass comprising lignin is contacted with a gas comprising ozone at a temperature of about 0° C. to about 50° C., then treated with aqueous ammonia. The readily saccharifiable carbohydrate-enriched biomass may be saccharified with an enzyme consortium to produce fermentable sugars.

Claims

1. A method for producing readily saccharifiable carbohydrate-enriched biomass, the method comprising:

(a) providing lignocellulosic biomass comprising lignin;

(b) contacting the biomass with an aqueous solution comprising ammonia to form a biomass-aqueous ammonia mixture, wherein the ammonia is present at a concentration at least sufficient to maintain alkaline pH of the biomass-aqueous ammonia mixture but wherein said ammonia is present at less than about 12 weight percent relative to dry weight of biomass, and further wherein the dry weight of biomass is at a high solids concentration of at least about 15 weight percent relative to the weight of the biomass-aqueous ammonia mixture, to produce an ammonia-treated biomass; and

(c) contacting the ammonia-treated biomass with a gas comprising ozone at a temperature of about 0°

C. to about 50°

C., whereby a readily saccharifiable carbohydrate-enriched biomass is produced.

3. The method of claim 1 or 2, wherein the gas comprises about 0.1 to about 20 percent by volume ozone.

4. The method of claim 1 or 2, wherein the gas further comprises air, nitrogen, oxygen, argon, or a combination thereof.

5. The method of claim 1, wherein the ratio of ozone to ammonia-treated biomass in step (c) is at least 1:

100 on a weight basis.

7. The method of claim 1, further comprising applying energy to the lignocellulosic biomass during step (b), to the ammonia-treated biomass during step (c), or to both.

9. The method of claim 1 or 2, wherein the lignocellulosic biomass, the ammonia-treated biomass, or both contain at least about 30 percent moisture.

10. The method of claim 1 or 2, wherein ammonia is selected from the group consisting of ammonia gas, ammonium hydroxide, urea, and combinations thereof.

11. The method of claim 1 or 2, wherein the aqueous solution comprising ammonia further comprises at least one additional base selected from the group consisting of sodium hydroxide, sodium carbonate, potassium hydroxide, potassium carbonate, calcium hydroxide, and calcium carbonate.

12. The method of claim 1 or 2, further comprising saccharifying the readily saccharifiable carbohydrate-enriched biomass with an enzyme consortium whereby fermentable sugars are produced.

13. The method of claim 12, further comprising fermenting the sugars to produce a target product.

2. A method for producing readily saccharifiable carbohydrate-enriched biomass, the method comprising:

(a) providing lignocellulosic biomass comprising lignin;

(b) contacting the biomass with a gas comprising ozone at a temperature of about 0°

C. to about 50°

C.

(c) contacting the ozone-treated biomass with an aqueous solution comprising ammonia to form a mixture comprising ozone-treated biomass and aqueous ammonia, wherein the ammonia is present at a concentration at least sufficient to maintain alkaline pH of the mixture but wherein said ammonia is present at less than about 12 weight percent relative to dry weight of ozone-treated biomass, and further wherein the dry weight of biomass is at a high solids concentration of at least about 15 weight percent relative to the weight of the mixture, whereby a readily saccharifiable carbohydrate-enriched biomass is produced.

6. The method of claim 2, wherein the ratio of ozone to lignocellulosic biomass in step (b) is at least 1:

100 on a weight basis.

8. The method of claim 2, further comprising applying energy to the lignocellulosic biomass during step (b), to the ozone-treated biomass during step (c), or to both.