Renewable aromatics from lignocellulosic lignin

Patent metadata

Field	Value
Publication number	US-10208076-B2
Application number	US-201514757851-A
Country	US
Kind code	B2
Filing date	Dec 23, 2015
Priority date	Dec 7, 2012
Publication date	Feb 19, 2019
Grant date	Feb 19, 2019

Abstract

The present invention provides novel and improved processes for treating a lignocellulosic biomass or technical lignin using ionic liquids to obtain lignin breakdown products and polysaccharide biomass components. Recycling of ionic liquids can be included in the methods of the invention.

First claim

What is claimed is:

1. A composition containing monomeric guaiacol, 4-ethyl guaiacol, 4-vinyl guaiacol, eugenol, syringol, 4-(1-propenyl) guaiacol, vanillin, allyl syringol, and guaiacylacetone, wherein the composition is formed by:
i) solubilizing a technical lignin in a solution comprising a water-miscible ionic liquid (IL) to generate a solubilized material;
ii) precipitating a fraction of the solubilized material with a polar solvent to generate a precipitated fraction and a supernatant;
iii) extracting the lignin compounds from the supernatant by contacting the supernatant with an extractant; and
iv) separating the lignin compounds from the extractant;
wherein the extractant is a non-polar solvent.

2. The composition of claim 1 , wherein the ionic liquid is [C2mim][OAc].

3. The composition of claim 1 , wherein the extractant is selected from the group consisting of benzene, pentane, and hexane.

4. The composition of claim 1 , wherein the solubilizing is performed at a temperature between about 100° C. and about 180° C.

5. The composition of claim 1 , wherein the polar solvent comprises water.

6. The composition of claim 1 , wherein the technical lignin comprises kraft lignin, a lignosulfate, alkali lignin, low sulfonate alkali lignin, or a combination thereof.

7. A method comprising:
i) contacting a technical lignin with an ionic liquid for at least about 3 hours to generate a solubilized material;
ii) precipitating a fraction of the solubilized material with a polar solvent to generate a precipitated fraction and a supernatant;
iii) extracting monomeric lignin compounds from the supernatant with an extractant; and
iv) separating the lignin compounds from the extractant;
wherein the monomeric lignin compounds are selected from the group consisting of guaiacol, 4-ethyl guaiacol, 4-vinyl guaiacol, eugenol, syringol, 4-(1-propenyl) guaiacol, vanillin, allyl syringol, guaiacylacetone, and combinations thereof, and
wherein the extractant is a non-polar solvent.

8. The method of claim 7 , wherein the ionic liquid is [C2mim][OAc].

9. The method of claim 7 , wherein the contacting is performed at a temperature between about 100° C. and about 180° C.

10. The method of claim 7 , wherein the polar solvent comprises water.

11. The method of claim 7 , wherein the technical lignin comprises kraft lignin, a lignosulfate, alkali lignin, low sulfonate alkali lignin, or a combination thereof.

Assignees

• Nat Tech & Eng Solutions Sandia Llc

Inventors

• Singh Seema
• Varanasi Patanjali
• Simmons Blake

Classifications

• 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

• D21C3/20

  with organic solvents {or in solvent environment} · CPC title

• C07G1/00 Primary

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