Method of digesting lignocellulosic material

Patent metadata

Field	Value
Publication number	US-9803317-B2
Application number	US-201314377610-A
Country	US
Kind code	B2
Filing date	Feb 8, 2013
Priority date	Feb 9, 2012
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

A method of digesting lignocellulosic material includes the steps of providing the lignocellulosic material and a caustic composition having a pH of at least about 10. The caustic composition includes water, an alkaline- or alkaline earth-metal hydroxide, and up to about 1 percent by weight based on a total weight of the composition of a branched digestion additive. The branched digestion additive has the structure: wherein A is at least one alkyleneoxy group and each alkyleneoxy group has from 2 to 4 carbon atoms, n is 0 or 1, B is a branched aliphatic hydrocarbon group having from 8 to 15 carbon atoms, X is H or B-0-(A) m , and each m is independently an average value from 3 to 30, and wherein the caustic composition has a Draves Wetting Time of less than 100 seconds as determined using ASTM D2281.

First claim

What is claimed is:

1. A method of digesting lignocellulosic material, said method comprising the steps of:
A. providing the lignocellulosic material;
B. providing a caustic composition having a pH of at least about 10 and consisting essentially of;
(i) water,
(ii) an alkaline- or alkaline earth-metal hydroxide present in an amount of from 7 to 20 parts by weight per 100 parts by weight of said caustic composition,
(iii) about 0.2 to 0.3 percent by weight based on a total weight of the composition of a branched digestion additive having the structure;

wherein A is at least one alkyleneoxy group and each alkyleneoxy group has from 2 to 3 carbon atoms, n is 1, B is a branched aliphatic hydrocarbon group having from 10 to 13 carbon atoms, X is H, and each m is independently an average value from 3 to 9; and
a second digestion additive present in an amount up to 0.5 weight percent that is different from the (iii) branched digestion additive and that comprises:

wherein each A is at least one alkyleneoxy group and each alkyleneoxy group has from 2 to 3 carbon atoms, each m is independently an average value from 3 to 9, n is 1, and each B is independently a branched aliphatic hydrocarbon group having from 10 to 13 carbon atoms,
wherein the caustic composition has a Draves Wetting Time of less than 10 seconds as determined using ASTM D2281, and
wherein the caustic composition is free of a sulfide; and comprises less than 0.1 weight percent of additional additives;

C. combining the lignocellulosic material and the caustic composition to form a mixture; and
D. heating the lignocellulosic material and/or the caustic composition to digest the lignocellulosic material.

2. A method as set forth in claim 1 wherein B of the branched digestion additive and the second branched digestion additive is further defined as a tridecyl group.

3. A method as set forth in claim 2 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

4. A method as set forth in claim 1 wherein B of the branched digestion additive and the second branched digestion additive is a 2-propyl heptanol group.

5. A method as set forth in claim 4 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

6. A method as set forth in claim 1 wherein each A of the branched digestion additive and the second branched digestion additive is an ethyleneoxy group, wherein each B of the branched digestion additive and the second branched digestion additive is a 2-propyl heptanol group, and wherein each m of the branched digestion additive and the second branched digestion additive is 4.

7. A method as set forth in claim 6 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

8. A method as set forth in claim 1 wherein each A of the branched digestion additive and the second branched digestion additive is an ethyleneoxy group, wherein each B of the branched digestion additive and the second branched digestion additive is a 2-propyl heptanol group, and wherein each m of the branched digestion additive and the second branched digestion additive is 5.

9. A method as set forth in claim 8 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

10. A method as set forth in claim 1 wherein each A of the branched digestion additive and the second branched digestion additive is an ethyleneoxy group, wherein each B of the branched digestion additive and the second branched digestion additive is 2-propyl heptanol group, and wherein each m of the branched digestion additive and the second branched digestion additive is 9.

11. A method as set forth in claim 10 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

12. A method as set forth in claim 1 wherein each A of the branched digestion additive and the second branched digestion additive is a combination of 5 moles of ethyleneoxy groups and 1 mole of a propyleneoxy group such that each m of the branched digestion additive and the second branched digestion additive totals 6, and wherein each B of the branched digestion additive and the second branched digestion additive is a 2-propyl heptanol group.

13. A method as set forth in claim 12 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

14. A method as set forth in claim 1 wherein each A of the branched digestion additive and the second branched digestion additive is a combination of 7 moles of ethyleneoxy groups and 1 mole of a propyleneoxy group such that each m of the branched digestion additive and the second branched digestion additive totals 8, and wherein each B of the branched digestion additive and the second branched digestion additive is a 2-propyl heptanol group.

15. A method as set forth in claim 14 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

16. A method as set forth in claim 1 wherein each A of the branched digestion additive and the second branched digestion additive is a combination of 9 moles of ethyleneoxy groups and 1 mole of a propyleneoxy group such that each m of the branched digestion additive and the second branched digestion additive totals 10, and wherein each B of the branched digestion additive and the second branched digestion additive is a 2-propyl heptanol group.

17. A method as set forth in claim 16 wherein the branched digestion additive is present in an amount of 0.2 weight percent based on a total weight of the composition and the alkaline- or alkaline earth-metal hydroxide is present in amount of from 7 to 9 parts by weight per 100 parts by weight of the caustic composition.

18. A method as set forth in claim 1 wherein each A of the branched digestion additive and the second branched digestion additive is an ethyleneoxy group, wherein each B of the branched digestion additive and the

Assignees

• Basf Se

Inventors

• Durocher David
• Friel Thomas C
• Zack Kenneth L

Classifications

• D21C5/00 Primary

  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 title

• D21C3/24

  Continuous processes · CPC title

• C08H8/00 Primary

  Macromolecular compounds derived from lignocellulosic materials {(pretreatment thereof B27N)} · CPC title

• D21C3/222

  Use of compounds accelerating the pulping processes · CPC title

• D21C3/02

  with inorganic bases or alkaline reacting compounds, e.g. sulfate processes · CPC title