Economical methods for performing oxidative catalytic pretreatment of plant biomass using a single-stage two oxidant process

Patent metadata

Field	Value
Publication number	US-11859145-B1
Application number	US-202217897566-A
Country	US
Kind code	B1
Filing date	Aug 29, 2022
Priority date	Aug 29, 2022
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

An improved alkaline pretreatment of biomass is provided that is a single-stage, two oxidant alkaline oxidative pretreatment process. The process uses a homogenous catalyst with at least two oxidants (Hydrogen peroxide and enhanced levels of oxygen) in an alkaline environment to catalytically pretreat lignocellulosic biomass in a single-stage oxidation reaction. The provided single-stage alkaline-oxidative pretreatment improves biomass pretreatment and increase enzymatic digestibility to improve the economic feasibility of production of lignocellulose derived sugars.

First claim

What is claimed is:

1. A method of pretreating plant biomass comprising catalytically pretreating the plant biomass in a single-stage alkaline oxidative pretreatment process, wherein the process comprises providing a metal-ligand complex, providing a base and adding at least two oxidants to the alkaline oxidative pretreatment process to produce a catalytically pretreated plant biomass and wherein the method does not include an alkaline pre-extraction step prior to the alkaline oxidative pretreatment process.

2. The method of claim 1 , wherein the oxidants are pressurized oxygen and hydrogen peroxide.

3. The method of claim 2 , wherein the oxygen pressure is from 100 psi to about 400 psi and the hydrogen peroxide is less than about 6% (w/w).

4. The method of claim 1 , wherein the at least two oxidants are present simultaneously in the pretreatment.

5. The method of claim 1 , wherein the alkaline oxidative pretreatment is conducted at a temperature from about 90° C. to about 140° C.

6. The method of claim 1 , wherein the method further comprises addition from about 5% to about 15% sodium hydroxide (w/w) to the alkaline oxidative pretreatment process.

7. The method of claim 1 , wherein the metal-ligand complex comprises a second ligand.

8. The method of claim 1 , wherein the catalytic pretreating step produces a liquid phase and the method further comprises:
separating the catalytically pretreated biomass from the liquid phase to produce separated catalytically pretreated biomass; and
hydrolyzing the separated catalytically pretreated biomass to produce hydrolyzed catalytically pretreated biomass.

9. The method of claim 8 , wherein the hydrolyzing is conducted with an enzyme, wherein the enzyme is at a concentration from about 5 mg protein/g glucan to about 30 mg protein/g glucan.

10. A method of reducing cost in a homogenous catalytic reaction comprising catalytically pretreating plant biomass with a metal-ligand complex and at least two oxidants present in a single-stage alkaline oxidative pretreatment process to produce a catalytically pretreated plant biomass, hydrolyzing the catalytically pretreated biomass to produce hydrolyzed catalytically pretreated biomass for use as a biofuel, wherein the method does not include an alkaline pretreatment step prior to the alkaline oxidative pretreatment step.

11. The method of claim 10 , wherein the oxidants are oxygen and hydrogen peroxide.

12. The method of claim 11 , wherein the oxygen pressure is from about 100 psi to about 400 psi and the hydrogen peroxide is about 6% (w/w) or less.

13. The method of claim 10 , wherein the metal-ligand complex comprises a second ligand.

14. The method of claim 10 , wherein the alkaline oxidative pretreatment is conducted at a temperature from about 70° C. to about 120° C.

15. The method of claim 10 , wherein the catalytic pretreating step produces a liquid phase and the method further comprises separating the catalytically pretreated biomass from the liquid phase to produce separated catalytically pretreated biomass.

16. The method of claim 10 , wherein the method reduces the minimum fuel selling price (MFSP) by about 40% relative to the MFSP of a method using only hydrogen peroxide as the oxidant.

17. A method of pretreating plant biomass comprising catalytically pretreating the plant biomass in a single-stage alkaline oxidative pretreatment process, wherein the process comprises providing a metal-ligand complex and adding at least two oxidants to the alkaline oxidative pretreatment process to produce a catalytically pretreated plant biomass and wherein the one of at least two oxidants comprises pressurized oxygen at least 100 psi.

18. The method of claim 17 , wherein the one of at least two oxidants further comprises hydrogen peroxide.

19. The method of claim 18 , wherein the pressurized oxygen is from 100 psi to about 400 psi and the hydrogen peroxide is less than about 6% (w/w).

20. The method of claim 17 , wherein the at least two oxidants are present simultaneously in the pretreatment.

Assignees

• Univ Michigan State
• Univ Montana State
• Wisconsin Alumni Res Found

Inventors

• Hegg Eric L
• Yuan Zhaoyang
• Hodge David B
• Stahl Shannon S
• Bals Bryan D

Classifications

• C12P2201/00

  Pretreatment of cellulosic or lignocellulosic material for subsequent enzymatic treatment or hydrolysis · CPC title

• C10L1/02 Primary

  essentially based on components consisting of carbon, hydrogen, and oxygen only · CPC title

• B01J23/04

  Alkali metals · CPC title

• B01J27/055

  with alkali metals, copper, gold or silver · CPC title

• C10L2200/0484

  Vegetable or animal oils · CPC title