Method to valorize 2G bioethanol waste streams

Patent metadata

Field	Value
Publication number	US-11623937-B2
Application number	US-202117411722-A
Country	US
Kind code	B2
Filing date	Aug 25, 2021
Priority date	Aug 25, 2020
Publication date	Apr 11, 2023
Grant date	Apr 11, 2023

Abstract

An integrated approach for utilizing waste products of 2G bio-refineries to fractionate the lignin of high purity. The present invention also provides a method of recycling of two waste products (2-G ethanol residue as the substrate (LRBR) and fusel oil/synthetic fusel oil (SFO) as one of the solvent) of the biorefineries in a beneficial manner to fractionate the lignin of high purity. The present method of separating high purity lignin comprises fractioning extractive-free lignin rich residue with a solvent, wherein the solvent is a mixture of SFO/Fusel oil and Formic acid. An optimized ratio of waste fusel oil and formic acid gave more than >85% yields of high purity lignin.

First claim

The invention claimed is:

1. A method for separating high purity lignin from waste streams, the method comprising:
i. removing extractives from the waste steam using by hot water treatment at 70-90° C., and repeating the step for 2-5 times;
ii. extracting solids obtained in previous step with technical spirit or fusel oil, and repeating the step 1-2 times to obtain extractive-free lignin rich residue;
iii. fractioning extractive-free lignin rich residue obtained in previous step with a solvent in high pressure reactor;
iv. separating the slurry obtained in previous step into solid and liquid fractions,
v. washing the solid fraction with solvent of step (iii), followed by washing with water; and
vi. combining the wash from step (v) to liquid fraction and recovering the lignin.

2. The method as claimed in claim 1 , wherein the waste steam is a bioethanol residue of the biorefineries and wherein extractive-free lignin rich residue is an extractive-free lignin rich bioethanol residue (LRBR).

3. The method as claimed in claim 1 , wherein the organic solvents used in step (iii) is selected from methanol, ethanol, propanol, butanol, acetone, formic acid, acetic acid, propionic acid, synthetic fusel oil (SFO), fusel oil or combination thereof.

4. The method as claimed in claim 3 , wherein the synthetic fusel oil comprises iso-amyl alcohol (55%), iso-butyl alcohol (18%), active amyl alcohol (10%), butyl alcohol (5%) propyl alcohol (5%) and Hexanol (2%).

5. The method as claimed in claim 1 , wherein the solvent is a mixture of SFO and formic acid.

6. The method as claimed in claim 5 , wherein the solvent is a mixture of SFO and formic acid in a ratio of 1:1.

7. The method as claimed in claim 1 , wherein the solvent is a mixture of fusel oil and formic acid.

8. The method as claimed in claim 7 , wherein the solvent is a mixture of fusel oil and formic acid in a ratio of 1:1.

9. The method as claimed in claim 1 , wherein the fractioning in step (iii) is at temperature of 160-200° C. and pressure of 10-12 bar.

10. The method as claimed in claim 1 , wherein the method is integrated to a method for production of bioethanol in biorefineries.

Assignees

• Indian Oil Corp Ltd
• Dept Of Biotechnology India

Inventors

• Satlewal Alok
• Agrawal Ruchi
• Kumar Ravindra
• Gupta Ravi Prakash
• Puri Suresh Kumar
• Saxena Deepak
• RAMAKUMAR Sankara Sri Venkata

Classifications

• C08L97/005 Primary

  Lignin · CPC title

• C07G1/00 Primary

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

• B01D11/0288

  Applications, solvents · CPC title

• C08H8/00

  Macromolecular compounds derived from lignocellulosic materials {(pretreatment thereof B27N)} · CPC title

• Y02E50/10

  Biofuels, e.g. bio-diesel · CPC title