Method to solubilize biomass under mild conditions

Patent metadata

Field	Value
Publication number	US-12358939-B2
Application number	US-202217836061-A
Country	US
Kind code	B2
Filing date	Jun 9, 2022
Priority date	Jun 9, 2021
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

A method of completely dissolving lignocellulosic biomass. The method includes the steps of dissolving a sample of biomass in an aqueous solution of strong acid and an amine-thiol to yield a first solution. A method for measuring lignin concentration in biomass via absorbance of the first solution at a wavelength of about 283 nm by comparing the measured absorbance to a standard curve of absorbance values made from solutions of known lignin concentration.

First claim

What is claimed is:

1. A method of dissolving biomass, including lignocellulosic biomass, the method comprising contacting an amount of biomass with an amount of an aqueous solution comprising a strong acid and an amine-thiol, wherein the amount of the aqueous solution is sufficient to completely dissolve the biomass.

2. The method of claim 1 , wherein the strong acid is selected from the group consisting of chloric acid (HClO 3 ), perchloric acid (HClO 4 ), hydrochloric acid (HCl), hydrobromic acid (HBr), hydroiodic acid (HI), nitric acid (HNO 3 ), phosphoric (H 3 PO 4 ), and sulfuric acid (H 2 SO 4 ).

3. The method of claim 1 , wherein the strong acid is sulfuric acid.

4. The method of claim 1 , wherein the amine-thiol is cysteine.

5. The method of claim 1 , wherein the strong acid is sulfuric acid and the amine-thiol is cysteine.

6. The method of claim 1 , wherein the method is conducted at a temperature of from about 20° C. to 30° C.

7. The method of claim 1 , wherein the aqueous solution comprises about 12 M strong acid and about 0.1 g/mL of amine-thiol.

8. The method of claim 1 , wherein the aqueous solution comprises about 12 M sulfuric acid and about 0.1 g/mL of cysteine.

9. A method of measuring lignin concentration in biomass, the method comprising:
(a) dissolving a sample of biomass suspected of containing lignocellulose in an aqueous solution comprising a strong acid and an amine-thiol to yield a first solution; and
(b) measuring absorbance of the first solution at a wavelength of about 283 nm; and
(c) determining lignin concentration in the first solution by comparing the measured absorbance in step (b) to a standard curve of absorbance values made from solutions of known lignin concentration.

10. The method of claim 9 , wherein the strong acid is selected from the group consisting of chloric acid (HClO 3 ), perchloric acid (HClO 4 ), hydrochloric acid (HCl), hydrobromic acid (HBr), hydroiodic acid (HI), nitric acid (HNO 3 ), phosphoric (H 3 PO 4 ), and sulfuric acid (H 2 SO 4 ).

11. The method of claim 9 , wherein the strong acid is sulfuric acid.

12. The method of claim 9 , wherein the amine-thiol is cysteine.

13. The method of claim 9 , wherein the strong acid is sulfuric acid and the amine-thiol is cysteine.

14. The method of claim 9 , wherein steps (a) and (b) are conducted a temperature of from about 20° C. to 30° C.

15. The method of claim 9 , wherein the aqueous solution of step (a) comprises about 12 M strong acid and about 0.1 g/mL of amine-thiol.

16. The method of claim 9 , wherein the aqueous solution of step (a) comprises about 12 M sulfuric acid and about 0.1 g/mL of cysteine.

Assignees

• Wisconsin Alumni Res Found

Inventors

• Lu Fachuang
• Ralph John

Classifications

• G01N21/31

  Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry {(G01N21/72 takes precedence)} · CPC title

• C13K1/02

  obtained by saccharification of cellulosic materials (manufacture of fodder A23K10/32) · CPC title

• C13K13/002

  Xylose · CPC title

• C08L97/005

  Lignin · CPC title

• C07G1/00 Primary

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