Fibre dissolution with enzymatic treatment

Patent metadata

Field	Value
Publication number	US-12247353-B2
Application number	US-201917254317-A
Country	US
Kind code	B2
Filing date	Jun 20, 2019
Priority date	Jun 21, 2018
Publication date	Mar 11, 2025
Grant date	Mar 11, 2025

Abstract

The present invention concerns a process for the dissolution of cellulose using an enzymatic treatment, followed by a chemical dissolution. Particularly, the invention relates to the utilization of oxidizing enzymes for said enzyme treatment step. The process of the invention will cause an improved dissolution of high molar mass cellulose fibres. The improved dissolution properties also cause an improved reactivity of the cellulose in subsequent reactions.

First claim

The invention claimed is:

1. A process for the dissolution of cellulose fibres comprising:
subjecting a cellulose raw material to an enzymatic treatment step using a lytic polysaccharide monooxygenase (LPMO) as an oxidative enzyme; and
dissolving the thus obtained enzyme-treated cellulose in a non-derivatising solvent, wherein the LPMO is used at a concentration of 0.25-7 mg/g of the cellulose raw material in the enzymatic treatment step, and

wherein the enzymatic treatment step is carried out in the presence of an electron donor,
wherein the electron donor is gallic acid, and wherein the gallic acid is provided at a concentration of 1-5 mM in the enzymatic treatment step.

2. The process of claim 1 , wherein the cellulose raw material is selected from softwood kraft fibres, dissolving grade pulps, recycled fibres or cotton cellulose.

3. The process of claim 1 , further comprising carrying out the enzyme treatment at ambient conditions, at a pH level of 5-8, and for 0.5-24 h.

4. The process of claim 1 , further comprising carrying out the enzyme treatment in the presence of oxygen, hydrogen peroxide, or both.

5. The process of claim 1 , further comprising selecting the non-derivatising solvent from those containing one or more metal ligands.

6. The process of claim 1 , further comprising using the solvent in an amount sufficient to cause wetting of the cellulose fibres.

7. The process of claim 1 , further comprising carrying out the dissolution treatment, using the non-derivatising solvent, at ambient conditions or sub-zero temperatures for a duration of 10 minutes or more.

8. The process of claim 1 , wherein the concentration of LPMO is 0.5-6 mg/g of cellulose raw material.

9. The process of claim 1 , wherein the concentration of LPMO is 1-5 mg/g of cellulose raw material.

10. The process of claim 1 , wherein the solvent comprises one or more metal ligands selected from the group consisting of copper, cadmium, lithium, and zinc.

11. The process of claim 1 , wherein the solvent comprises cupriethylenediamine (CED) or NaOH/ZnO.

12. The process of claim 1 , wherein the (LPMO) LPMO produced from a strain of Trichoderma reesei lacking genes encoding for cbh1, cbh2, egl1, and egl2.

13. The process of claim 1 , wherein the solvent comprises cupriethylenediamine (CED).

Assignees

• Teknologian Tutkimuskeskus Vtt Oy

Inventors

• Marjamaa Kaisa
• Aro Nina
• Kruus Kristiina
• Rahikainen Jenni

Classifications

• C12N9/0083

  Miscellaneous (1.14.99) · CPC title

• D21C5/005 Primary

  Treatment of cellulose-containing material with microorganisms or enzymes · CPC title

• C12P19/04 Primary

  Polysaccharides, i.e. compounds containing more than five saccharide radicals attached to each other by glycosidic bonds · CPC title