Process for the production of alcohol

• US 8,709,769 B2
• Filed: 10/02/2009
• Issued: 04/29/2014
• Est. Priority Date: 10/22/2008
• Status: Active Grant

• Current Assignee: Silvanova LLC
• Original Assignee: Weyland AS
• Inventors: Weydahl, Karl Ragnar
• Primary Examiner(s): Monshipouri, Maryam
• Application Number:
  US13/125,069
• Publication Number:
  US 20110294181A1
• Time in Patent Office: 1,670 Days
• Field of Search: 127/37, 445/89, 435/163
• US Class Current: 435/163
• CPC Class Codes: C13K 1/02 obtained by saccharification of cellulosic materials manufacture of fodder A23K10/32
• CPC Class Codes: Y02E 50/10 Biofuels, e.g. bio-diesel

Abstract

The invention provides a process for producing alcohol from a cellulosic material, said process comprising the steps of: (i) hydrolyzing said cellulosic material with an aqueous acid to produce a hydrolysate; (ii) extracting acid and water from said hydrolysate with a water-miscible organic extraction solvent to yield (a) a first aqueous acidic solution containing said extraction solvent and (b) a residue containing sugars, —(iii) subjecting said residue to an oligosaccharide cleavage reaction to yield an aqueous solution of fermentable sugars; (iv) fermenting said fermentable sugars and distilling alcohol from the resulting fermented mixture; (v) evaporating said extraction solvent from said first solution to yield (a) a second aqueous acid solution containing no more than 10% wt., preferably no more than 5% wt., of said extraction solvent and (b) gaseous extraction solvent; (vi) condensing said gaseous extraction solvent for recycling; and, optionally, (vii) concentrating said second aqueous acid solution for recycling; wherein said extraction solvent is liquid at the temperature and pressure of step (ii), has a boiling point of from 25 to 60° C. at a pressure in the range 1 to 8 bar, and is such that water-soluble oligosaccharides are precipitated from solution by its addition in step (ii).

Claims

1. A process for the production of a residue containing sugars from a cellulosic material, said process comprising the steps of:

(i) hydrolyzing said cellulosic material with an aqueous acid to produce a hydrolysate;

(ii) extracting acid and water from said hydrolysate with a water-miscible organic extraction solvent to yield (a) a first aqueous acidic solution containing said extraction solvent and (b) the residue containing sugars;

(iii) evaporating said extraction solvent from said first solution to yield (a) a second aqueous acid solution containing no more than 10% wt. of said extraction solvent and (b) gaseous extraction solvent;

(iv) condensing said gaseous extraction solvent for recycling; and

, optionally,

(v) concentrating said second aqueous acid solution for recycling;

wherein said extraction solvent is liquid at the temperature and pressure of step (ii), has a boiling point of from 25 to 60°

C. at a pressure in the range 1 to 8 bar, comprises a solvent having a boiling point at 1 bar of below 20°

C., and is such that water-soluble oligosaccharides are precipitated from solution by its addition in step (ii).

2. The process as claimed in claim 1, further comprising the steps of:

subjecting said residue containing sugars to an oligosaccharide cleavage reaction to yield an aqueous solution of fermentable sugars; and

fermenting said fermentable sugars and distilling alcohol from the resulting fermented mixture.

3. The process as claimed in claim 1, said process further comprising the step of:

drying said residue containing sugars to yield a sugar composition.

4. The process as claimed in any one of claims 2, 1 or 3, wherein said extraction solvent comprises a C_2-3 ether.

8. The process as claimed in any one of claims 2, 1, 3, 6, 5 or 7 wherein extraction step (ii) is performed at a temperature within 15°

C. and a pressure within 1 bar of the temperature and pressure of hydrolysis step (i).

9. The process as claimed in any one of claims 2, 1, 3, 6, 5 or 7 wherein evaporation step (iii) is performed at a temperature within 15°

C. and a pressure within 5 bar of the temperature and pressure of extraction step (ii).

10. The process as claimed in any one of claims 2, 1, 3, 6, 5 or 7 wherein condensation step (iv) is performed at a temperature within 15°

C. and a pressure within 1 bar of the temperature and pressure of extraction step (ii).

15. The process as claimed in any one of claims 2, 1, 3, 6, 5, 7, 12, 11 or 13 for the production of ethanol.

16. The process as claimed in any one of claims 2, 1, 3, 6, 5, 7, 12, 11 or 13 wherein said extraction solvent comprises dimethyl ether.

17. The process as claimed in claim 16 wherein said extraction solvent further comprises ethanol.

5. A process for the production of a residue containing sugars from a cellulosic material, said process comprising the steps of:

(i) hydrolyzing said cellulosic material with an aqueous acid to produce a hydrolysate;

(ii) extracting acid and water from said hydrolysate with a water-miscible organic extraction solvent comprising a C_2-3 ether to yield (a) a first aqueous acidic solution containing said extraction solvent and (b) the residue containing sugars;

(iii) evaporating said extraction solvent from said first solution to yield (a) a second aqueous acid solution containing no more than 10% wt. of said extraction solvent and (b) gaseous extraction solvent;

(iv) condensing said gaseous extraction solvent for recycling; and

, optionally,

(v) concentrating said second aqueous acid solution for recycling;

wherein said extraction solvent is liquid at the temperature and pressure of step (ii) and is such that water-soluble oligosaccharides are precipitated from solution by its addition in step (ii).

6. The process as claimed in claim 5, said process further comprising the steps of:

subjecting said residue containing sugars to an oligosaccharide cleavage reaction to yield an aqueous solution of fermentable sugars; and

fermenting said fermentable sugars and distilling alcohol from the resulting fermented mixture.

7. The process as claimed in claim 5, said process further comprising the step of:

drying said residue containing sugars to yield a sugar composition.

11. A process for the production of a residue containing sugars from a cellulosic material, said process comprising the steps of:

(i) hydrolyzing said cellulosic material with an aqueous acid to produce a hydrolysate;

(ii) extracting acid and water from said hydrolysate with a water-miscible organic extraction solvent to yield (a) a first aqueous acidic solution containing said extraction solvent and (b) the residue containing sugars;

(iii) evaporating said extraction solvent from said first solution to yield (a) a second aqueous acid solution containing no more than 10% wt. of said extraction solvent and (b) gaseous extraction solvent;

(iv) condensing said gaseous extraction solvent for recycling; and

, optionally,

(v) concentrating said second aqueous acid solution for recycling;

wherein said extraction solvent is liquid at the temperature and pressure of step (ii), has a boiling point of from 25 to 60°

C. at a pressure in the range 1 to 8 bar, and is such that water-soluble oligosaccharides are precipitated from solution by its addition in step (ii), wherein extraction step (ii) is performed at a temperature within 15°

C. and a pressure within 1 bar of the temperature and pressure of hydrolysis step (i), wherein evaporation step (iii) is performed at a temperature within 15°

C. and a pressure within 5 bar of the temperature and pressure of extraction step (ii), and wherein condensation step (iv) is performed at a temperature within 15°

C. and a pressure within 1 bar of the temperature and pressure of extraction step (ii).

12. The process as claimed in claim 11, said process further comprising the steps of:

subjecting said residue containing sugars to an oligosaccharide cleavage reaction to yield an aqueous solution of fermentable sugars; and

fermenting said fermentable sugars and distilling alcohol from the resulting fermented mixture.

13. The process as claimed in claim 11, said process further comprising the step of:

drying said residue containing sugars to yield a sugar composition.

14. The process as claimed in any one of claims 12, 11 or 13 wherein extraction step (ii) is performed at a temperature within 10°

C. of the temperature of hydrolysis step (i), wherein evaporation step (iii) is performed at a temperature within 10°

C. of the temperature of extraction step (ii), and wherein condensation step (iv) is performed at a temperature within 10°

C. of the temperature of extraction step (ii).