Lignin recovery and furfural production from prehydrolysate streams

Patent metadata

Field	Value
Publication number	US-2020325111-A1
Application number	US-201716088980-A
Country	US
Kind code	A1
Filing date	Apr 20, 2017
Priority date	Apr 20, 2016
Publication date	Oct 15, 2020
Grant date	—

Abstract

The present invention relates to a method of producing furfural and extracting lignin from a hemi-cellulosic biomass solution comprising a total quantity of C5 sugars, comprising the steps of heating the hemi-cellulosic biomass solution to a temperature of at least about 200° C.; acidifying the hemi-cellulosic biomass solution with acid to produce the furfural in vapor phase; and condensing the furfural to recover furfural in solution, wherein the furfural is produced at a total molar yield of at least 70% of moles of furfural produced/the total moles C5 sugars present in the initial hemi-cellulosic biomass solution. Low molecular weight lignin can also be recovered from the hemi-cellulosic biomass solution prior to furfural production by membrane concentration, acidification, coagulation and filtration.

First claim

1 . A method of producing furfural comprising:
providing a hemi-cellulosic biomass solution comprising a total quantity of C5 sugars; heating the hemi-cellulosic biomass solution to a temperature of at least about 200° C.; acidifying the hemi-cellulosic biomass solution with acid to produce furfural in vapor phase; and condensing the furfural to recover furfural in solution,
wherein the furfural is produced at a total yield of at least 70% moles of furfural produced/the total moles of C5 sugars present in the initial hemi-cellulosic biomass solution.

2 . The method of claim 1 , wherein the total molar yield is at least 75%.

3 . The method of claim 1 , wherein the acid used to acidify the hemi-cellulosic biomass solution is sulfuric acid.

4 . The method of claim 3 , wherein the sulfuric acid has a concentration of 0.1%-0.5% w/w of the hemi-cellulosic biomass solution.

5 . (canceled)

6 . The method of claim 1 , wherein the temperature to which the hemi-cellulosic biomass solution is heated is between 220° C.-240° C.

7 . The method of claim 1 , wherein the temperature to which the hemi-cellulosic biomass solution is heated is 240° C.

8 . The method of claim 1 , further comprising the step of purifying and concentrating the furfural by distillation.

9 . The method of claim 1 , wherein the furfural is separated from water and acetic acid by distillation.

10 . The method of claim 1 , wherein the hemi-cellulosic biomass solution is from hardwood chips, hardwood (HW) lignin plant; black liquor from HW pulp mills; red liquor from hardwood sulfite pulp mills; C5 sugar streams from thermo-mechanical pulping bio-plants; C5-rich sugar stream from CNC production; and non-wood sources.

11 . The method of claim 10 , wherein the non-wood sources are oats and annual plants.

12 . The method of claim 1 , wherein said hemi-cellulosic biomass solution is a prehydrolysate stream.

13 . The method of claim 12 , wherein said prehydrolysate stream is obtained by contacting the hemi-cellulosic biomass with steam, hot water, a mild acidic stream, an alkaline solution, or a solvent.

14 . The method of claim 1 , wherein the furfural is produced at a total molar yield of at least 75.7% moles of furfural produced/the total moles C5 sugars present in the initial hemi-cellulosic biomass solution.

15 . The method of claim 1 , wherein the furfural is produced at a total molar yield of at least 80% of moles of furfural produced/the total moles C5 sugars present in the initial hemi-cellulosic biomass solution.

16 . The method of claim 1 , wherein the furfural is produced at a total molar yield of at least 85% of moles of furfural produced/the total moles C5 sugars present in the initial hemi-cellulosic biomass solution.

17 . The method of claim 1 , further comprising a first step of extracting lignin from the provided hemi-cellulosic biomass solution by concentration using membranes.

18 . The method of claim 17 , wherein the membranes cut-off are 1000 Da.

19 . The method of claim 17 , wherein acetic acid is recovered from the permeate from the 1000 Da cut-off membranes using a hollow fiber contactor.

20 . The method of claim 18 , wherein the hemi-cellulosic biomass solution is acidified to pH 2 after being concentrated with the 1000 Da cut-off membranes.

21 . A method of producing furfural comprising:
providing a hemi-cellulosic biomass solution comprising a total quantity of C5 sugars; passing the hemi-cellulosic biomass solution through a cut-off membrane to separate the lignin from the hemi-cellulosic biomass solution;
acidifying the concentrated hemi-cellulosic biomass solution, coagulating the lignin particles forming a lignin cake;
separating the lignin cake by filtration;
heating the filtered hemi-cellulosic biomass solution at atmospheric pressure or less, to a temperature of at least about 200° C.;
acidifying the hemi-cellulosic biomass solution with acid to produce the furfural in vapour phase; and
condensing the furfural to recover furfural in solution,

wherein the furfural is produced at a total molar yield of at least 76% of moles of furfural produced/the total moles C5 sugars present in the initial hemi-cellulosic biomass solution.

Assignees

• Fpinnovations

Inventors

• Jemaa Naceur
• Mazar Adil
• Wafa Al Dajani Waleed
• Paleologou Michael

Classifications

• Y02E50/10

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

• C07D307/50 Primary

  Preparation from natural products · CPC title