Liquefaction process for the recovery of homogeneous lignin

Patent metadata

Field	Value
Publication number	US-2023331759-A1
Application number	US-202217722997-A
Country	US
Kind code	A1
Filing date	Apr 18, 2022
Priority date	Apr 18, 2022
Publication date	Oct 19, 2023
Grant date	—

Abstract

A method for the recovery of lignin includes dissolving black liquor in solvent to form a mixture having a pH greater than or equal to about 12 to less than or equal to about 14. The pH of the mixture is then adjusted to greater than or equal to about 3 to less than or equal to about 7. The mixture is liquefacted, which includes increasing a temperature of the mixture to a target temperature, maintaining the target temperature for a period of time, and cooling the mixture to room temperature. Following liquefaction, the mixture is filtered to separate soluble and insoluble fractions of the mixture. The soluble fraction includes a lignin product having a polydispersity greater than or equal to about 1.78 to less than or equal to about 2.56.

First claim

What is claimed is:

1 . A method for recovery of lignin, the method comprising:
dissolving black liquor in solvent to form a mixture, wherein a pH of the mixture is greater than or equal to about 12 to less than or equal to about 14; adjusting the pH of the mixture to greater than or equal to about 3 to less than or equal to about 7; liquefacting the mixture, wherein liquefacting comprises:
increasing a temperature of the mixture to a target temperature;
maintaining the target temperature for a period of time; and
cooling the mixture to room temperature; and
filtering the mixture following liquefacting the mixture to separate soluble and insoluble fractions of the mixture, wherein the soluble fraction comprises a lignin product.

2 . The method according to claim 1 , wherein the solvent comprises methanol.

3 . The method according to claim 1 , wherein a mass ratio of the black liquor to the solvent in the mixture is greater than or equal to about 1:10 to less than or equal to about 1:5.

4 . The method according to claim 1 , wherein the step of adjusting the pH of the mixture is done using at least one of an organic acid and an inorganic acid.

5 . The method according to claim 1 , wherein the target temperature comprises a temperature greater than or equal to about 100° C. to less than or equal to about 200° C.

6 . The method according to claim 1 , wherein the period of time during the step of maintaining the target temperature is greater than or equal to about 1 minute to less than or equal to about 15 minutes.

7 . The method according to claim 1 , wherein a polydispersity of the lignin product is greater than or equal to about 1.78 to less than or equal to about 2.56.

8 . The method according to claim 1 , wherein the solvent is recycled after the step of filtering the mixture.

9 . A foam part for a vehicle comprising the lignin product recovered from the method according to claim 1 .

10 . A method for recovery of lignin, the method comprising:
dissolving black liquor in solvent to form a mixture; adjusting a pH of the mixture to greater than or equal to about 3 to less than or equal to about 7; liquefacting the mixture, wherein liquefacting comprises:
increasing a temperature of the mixture to a target temperature;
maintaining the target temperature for a period of time; and
cooling the mixture to room temperature; and
filtering the mixture following liquefacting the mixture to separate soluble and insoluble fractions of the mixture, wherein the soluble fraction comprises a lignin product, wherein a polydispersity of the lignin product is greater than or equal to about 1.78 to less than or equal to about 2.56.

11 . The method according to claim 10 , wherein the solvent comprises methanol.

12 . The method according to claim 10 , wherein a mass ratio of the black liquor to the solvent in the mixture is greater than or equal to about 1:10 to less than or equal to about 1:5.

13 . The method according to claim 10 , wherein the step of adjusting of the pH of the mixture is done using at least one of an organic acid and an inorganic acid.

14 . The method according to claim 10 , wherein the target temperature comprises a temperature greater than or equal to about 100° C. to less than or equal to about 200° C.

15 . The method according to claim 10 , wherein the period of time during the step of maintaining the target temperature is greater than or equal to about 1 minute to less than or equal to about 15 minutes.

16 . A method for recovery of lignin, the method comprising:
dissolving black liquor in methanol to form a mixture; adjusting a pH of the mixture to greater than or equal to about 3 to less than or equal to about 7 using at least one of an organic acid and an inorganic acid; liquefacting the mixture, wherein liquefacting comprises:
increasing a temperature of the mixture to a target temperature;
maintaining the target temperature for a period of time; and
cooling the mixture to room temperature; and
filtering the mixture following liquefacting the mixture to separate soluble and insoluble fractions of the mixture, wherein the soluble fraction comprises a lignin product.

17 . The method according to claim 16 , wherein a mass ratio of the black liquor to methanol in the mixture is greater than or equal to about 1:10 to less than or equal to about 1:5.

18 . The method according to claim 16 , wherein the target temperature comprises a temperature greater than or equal to about 100° C. to less than or equal to about 200° C.

19 . The method according to claim 16 , wherein the period of time during the step of maintaining the target temperature is greater than or equal to about 1 minute to less than or equal to about 15 minutes.

20 . The method according to claim 16 , wherein a polydispersity of the lignin product is greater than or equal to about 1.78 to less than or equal to about 2.56.

Assignees

• Ford Global Tech Llc

Inventors

• Kiziltas Alper
• Xie Xinfeng
• Quan Peng
• Mielewski Deborah Frances

Classifications

• C07G1/00 Primary

  Low-molecular-weight derivatives of lignin (high-molecular-weight derivatives of lignin {C08H6/00}) · CPC title

• D21C11/0007

  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 title