Supercritical hydrolysis of biomass
Methods are disclosed for processing biomass by single-stage supercritical hydrolysis, wherein the biomass has been size reduced.
1. A method, comprising:
size reducing a starting lignocellulosic biomass to form a lignocellulosic biomass having a particle size less than about 500 μm;
forming a mixture comprising:
water; and
said lignocellulosic biomass having a particle size less than about 500 μm; and
contacting water at a temperature of at least about 375° C. and a pressure of at least about 221 bar with said mixture for a duration sufficient to produce at least one C 5 or C 6 saccharide;
wherein said mixture is substantially free of exogenous acid.
2. The method of claim 1 ,
wherein said size reducing comprises steam exploding said starting lignocellulosic biomass in the presence of ammonia.
3. The method of claim 1 ,
wherein said size reducing comprises steam exploding said starting lignocellulosic biomass in the presence of sulfur dioxide.
4. The method of claim 1 ,
wherein said lignocellulosic biomass is derived from thermally processed cellulosic biomass.
5. The method of claim 1 ,
wherein said lignocellulosic biomass is derived from chemically processed cellulosic biomass.
6. The method of claim 1 ,
wherein said lignocellulosic biomass is derived from agricultural residue, waste lignocellulosic biomass, or a combination thereof.
7. The method of claim 1 ,
wherein said lignocellulosic biomass has a particle size of about 10 μm to about 300 μm.
8. The method of claim 1 ,
wherein said C 5 or C 6 saccharide is a C 5 monosaccharide, and said C 5 monosaccharide is xylose.
9. The method of claim 1 ,
wherein said C 5 or C 6 saccharide is a C 6 monosaccharide, and said C 6 monosaccharide is glucose.
10. The method of claim 1 ,
wherein said C 5 or C 6 saccharide is a C 6 monosaccharide, and said C 6 monosaccharide is mannose.
11. The method of claim 1 , further comprising:
heating said mixture to a temperature of at least about 150° C. subsequent to said size reducing step and prior to said contacting step.
12. The method of claim 1 , further comprising:
fermenting at least one of said C 5 and C 6 saccharide using an oligomer fermenter.
13. The method of claim 1 , further comprising:
recovering at least one component released into a gas phase, wherein said component is acetic acid.
14. The method of claim 1 ,
wherein said duration is about 2 seconds or less.
15. The method of claim 1 ,
wherein at least a portion of said method employs a digester.
16. The method of claim 15 ,
wherein said size reducing comprises steam exploding said starting lignocellulosic biomass.
17. The method of claim 1 ,
wherein said starting lignocellulosic biomass is obtained from treatment of biomass in a digester.
18. The method of claim 17 ,
wherein said size reducing comprises steam exploding said starting lignocellulosic biomass.
19. The method of claim 1 ,
wherein said water in said contacting is at a temperature of about 390° C. to about 470° C. and a pressure of at least about 225 bar.
20. The method of claim 1 ,
wherein said mixture prior to said contacting has a solids content of about 10 wt. % to about 35 wt. %.