PROCESS FOR THE PRODUCTION OF BIOFUEL FROM PLANT MATERIALS

• US 20070259412A1
• Filed: 05/08/2007
• Published: 11/08/2007
• Est. Priority Date: 05/08/2006
• Status: Active Grant

• Current Assignee: Vertichem Corporation
• Original Assignee: Biojoule Limited (Pure Power Global)
• Inventors: BELANGER, Helene, WATSON, James D., Yao, Jia-Long, PRESTIDGE, Ross L., LOUGH, Tony James
• Granted Patent: US 7,649,086 B2
• Time in Patent Office: Days
• US Class Current: 435/161
• CPC Class Codes: D21C 11/0007 Recovery of by-products, i.e. compounds other than those necessary for pulping, for multiple uses or not otherwise provided for volatile compounds obtained by decomposition of spent liquors in order to regenerate them D21C11/125; compounds obtained by fractionating the liquors in order to regenerate them D21C11/0042
• CPC Class Codes: D21C 3/20 with organic solvents or in solvent environment
• CPC Class Codes: D21C 5/00 Other processes for obtaining cellulose, e.g. cooking cotton linters obtaining fibres for spinning D01C; Processes characterised by the choice of cellulose-containing starting materials
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

An integrated process for the production of ethanol from woody plant material is provided, the process comprising: contacting a continuous flow of the plant material with a counter-current continuous flow of an aqueous ethanol solution at elevated temperature and pressure to provide plant material depleted of lignin; removing ethanol from the lignin-depleted plant material; contacting a continuous flow of the lignin-depleted plant material with water at elevated temperature and pressure to solubilize xylose within the plant material; and hydrolyzing cellulose present in the plant material to form glucose, which in turn is fermented to produce ethanol.

Claims

1. A process for the treatment of plant material, comprising:

(a) contacting a continuous flow of the plant material with a co-current or counter-current continuous flow of an aqueous ethanol solution at a first elevated temperature and pressure for a period of time sufficient to produce plant pulp material and a mixture comprising ethanol, ethanol-soluble lignin and water, wherein the plant pulp material is depleted of lignin and has a high concentration of cellulose;

(b) separating the plant pulp material from the mixture and recovering the ethanol-soluble lignin from the mixture;

(c) contacting the plant pulp material with water at a second elevated temperature and pressure for a period of time sufficient to remove hemicellulose sugars from the plant pulp material;

(d) separating the water from the plant pulp material and recovering water-soluble sugars, acetic acid and/or furfural from the water; and

(e) contacting the resulting plant pulp material with;

(i) an aqueous solution comprising cellulase, β

-glucosidase and temperature-tolerant yeast, (ii) yeast growth media, and (iii) buffer, whereby cellulose present in the plant pulp material is hydrolyzed to glucose.

2. The method of claim 1, further comprising fermenting the glucose to produce ethanol.

3. The method of any claim 1, wherein the plant material is a lignocellulosic material selected from the group consisting of:

woody or herbaceous materials, agricultural or forestry residues, and dedicated energy crops.

4. The method of claim 1, wherein the plant material is selected from the group consisting of:

Salix, Poplar, Eucalyptus, switch grass, miscanthus, sugar cane bagasse, soybean stover, corn stover, rice straw, barley straw, wheat straw, corn fiber, wood fiber, and combinations thereof.

5. The method of claim 1, wherein the plant material is from a plant selected from the group consisting of:

Salix species and wheat.

6. The method of claim 1, wherein the aqueous ethanol solution comprises 50% to 80% ethanol.

7. The method of claim 1, wherein step (a) is carried out substantially in the absence of an acid catalyst.

8. The method of claim 1, wherein the first elevated temperature is between 170°

C. and 210°

C.

9. The method of claim 1, wherein the first elevated pressure is between 19-30 barg.

10. The method of claim 1, wherein the second elevated temperature is between 160°

C. and 220°

C.

11. The method of claim 1, wherein the second elevated pressure is between 12-25 barg.

12. An integrated process for the treatment of plant material, comprising:

(a) contacting the plant material with an aqueous ethanol solution at a first elevated temperature and pressure for a period of time sufficient to produce plant pulp material and a mixture comprising ethanol, ethanol-soluble lignin and water, wherein the plant pulp material is depleted of lignin and has a high concentration of cellulose;

(b) separating the plant pulp material from the mixture and recovering the ethanol-soluble lignin from the mixture;

(c) contacting the plant pulp material with water at a second elevated temperature and pressure for a period of time sufficient to remove hemicellulose sugars from the plant pulp material; and

(d) separating the water from the plant pulp material and recovering water soluble sugar, acetic acid and/or furfural from the water.

13. The method of claim 12, wherein the plant material is a lignocellulosic material selected from the group consisting of:

woody or herbaceous materials, agricultural or forestry residues, and dedicated energy crops.

14. The method of claim 12, wherein the plant material is selected from the group consisting of:

Salix, Poplar, Eucalyptus, switch grass, miscanthus, sugar cane bagasse, soybean stover, corn stover, rice straw, barley straw, wheat straw, corn fiber, wood fiber, and combinations thereof.

15. The method of claim 12, wherein the plant material is from a plant selected from the group consisting of:

Salix species and wheat.

16. The method of claim 12, wherein the aqueous ethanol solution comprises 50% to 80% ethanol.

17. The method of claim 12, wherein the first elevated temperature is between 170°

C. and 210°

C. and the first elevated pressure is between 19-30 barg.

18. The method of claim 12, wherein step (a) is carried out substantially in the absence of an acid catalyst.

19. The method of claim 12, wherein the second elevated temperature is between 160°

C. and 220°

C. and the second elevated pressure is between 12-25 barg.

20. The method of claim 12, further comprising contacting plant pulp material from step (d) with (i) an aqueous solution comprising cellulase, β

-glucosidase and temperature-tolerant yeast, (ii) yeast growth media, and (iii) buffer for a period time sufficient to hydrolyze cellulose present in the plant pulp material to glucose.

21. The method of claim 12, further comprising fermenting the glucose to produce ethanol.

22. A method for propagating plants of a Salix species, the method comprising:

(a) culturing at least one shoot of a first plant selected from the group consisting of Salix species and collecting at least one cutting from the shoot, wherein the cutting contains at least one node; and

(b) cultivating the cutting in a composition for a period of time sufficient to form a second plant, wherein the composition comprises benzyladenine, activated charcoal and at least one medium selected from the group consisting of;

Murashige and Skoog medium and McCown Woody Plant medium.

23. The method of claim 22, further comprising:

(a) obtaining at least one subsequent cutting from the second plant, wherein the subsequent cutting contains at least one node; and

(b) culturing the subsequent cutting in McCown Woody Plant medium for a period of time sufficient to form a subsequent plantlet.

24. The method of claim 22, wherein the plant is selected from the group consisting of:

S. viminalis and S. schwerinii ‘

Kinuyanagi’

.