Method for upgrading pyrolysis oil through seawater electrochemical pretreatment of biomass feedstock

Patent metadata

Field	Value
Publication number	US-11732196-B2
Application number	US-202217851952-A
Country	US
Kind code	B2
Filing date	Jun 28, 2022
Priority date	Nov 22, 2021
Publication date	Aug 22, 2023
Grant date	Aug 22, 2023

Abstract

Provided is a method for upgrading pyrolysis oil through seawater electrochemical pretreatment of biomass and use thereof. The method includes: (1) crushing and sieving a biomass raw material to obtain a crushed biomass raw material, adding the crushed biomass raw material to a salt solution and mixing to be uniform to obtain a reactant mixture; performing an electrolytic reaction on the reactant mixture under conditions of stirring and an external voltage of 5-15 V for 2-8 hours to obtain a product mixture; after the electrolytic reaction, subjecting the product mixture to a suction filtration, collecting a filter cake, washing the filter cake and drying to obtain a pretreated biomass, and (2) subjecting the pretreated biomass obtained in step (1) to a pyrolysis reaction at a temperature of 400-600° C. for 30-90 minutes in a protective gas atmosphere, and collecting a pyrolysis oil by an organic solvent.

First claim

What is claimed is:

1. A method for upgrading pyrolysis oil through seawater electrochemical pretreatment of biomass, the method comprising:
(1) a step of electrochemical pretreatment comprising:
crushing and sieving a biomass raw material to obtain a crushed biomass raw material;
adding the crushed biomass raw material to a salt solution, and mixing the crushed biomass raw material and the salt solution to be uniform to obtain a reactant mixture;
performing an electrolytic reaction on the reactant mixture under conditions of stirring and an external voltage of 5-15 V for 2-8 hours to obtain a product mixture;
after the electrolytic reaction, subjecting the product mixture to a suction filtration, collecting a filter cake, washing the filter cake and drying to obtain a pretreated biomass,
wherein the salt solution is seawater with a concentration of NaCl of 2-6.5% by mass or a NaCl solution with a concentration of NaCl of 2-6.5% by mass; and
(2) a step of pyrolysis comprising:
subjecting the pretreated biomass obtained in step (1) to a pyrolysis reaction at a temperature of 400-600° C. for 30-90 minutes in a protective gas atmosphere,
and collecting a pyrolysis oil by dissolving the pyrolysis oil in an organic solvent.

2. The method of claim 1 , wherein
the seawater or the NaCl solution in step (1) has a concentration of NaCl of 2-5% by mass; and
a solid-to-liquid ratio of the biomass raw material to the salt solution in step (1) is in the range of 1 g: (100-150) mL.

3. The method of claim 2 , wherein
the seawater or the NaCl solution in step (1) has a concentration of NaCl of 2-3.5% by mass; and
the solid-to-liquid ratio of the biomass raw material to the salt solution in step (1) is 1 g:100 mL.

4. The method of claim 3 , wherein
the seawater or the NaCl solution in step (1) has a concentration of NaCl of 3.5% by mass.

5. The method of claim 1 , wherein
the mixing in step (1) is performed at 400-800 r/min for 10-40 minutes;
the electrolytic reaction in step (1) is performed under an external voltage of 10-15 V;
the electrolytic reaction in step (1) is performed for 4-8 hours;
the pyrolysis reaction in step (2) is performed at a temperature of 500° C.;
the pyrolysis reaction in step (2) is performed for 30 minutes;
the collecting in step (2) is performed at a condensation temperature of −10 to −20° C.; and
the organic solvent in step (2) is acetone.

6. The method of claim 5 , wherein
the mixing in step (1) is performed at 600 r/min for 20 minutes;
the electrolytic reaction in step (1) is performed under an external voltage of 15 V;
the electrolytic reaction in step (1) is performed for 8 hours; and
the collecting in step (2) is performed at a condensation temperature of −18° C.

7. The method of claim 1 , wherein
the electrolytic reaction is performed using at least two graphite electrodes, wherein a distance between said at least two graphite electrodes is 6 cm;
the external voltage in step (1) is provided by a direct current power supply; and
the electrolytic reaction is performed in an undivided electrolytic tank.

8. The method of claim 1 , wherein
the biomass raw material in step (1) is a waste agricultural and forestry biomass raw material;
the sieving in step (1) is performed by a 40-200 mesh sieve;
the washing in step (1) is performed using water, acetone and water sequentially;
the drying in step (1) is performed at a temperature of 50-105° C.;
the drying in step (1) is performed for 5-24 hours; and
the protective gas in step (2) is an inert gas.

9. The method of claim 8 , wherein
the biomass raw material in step (1) is a corn stalk;
the sieving in step (1) is performed by an 80-100 mesh sieve;
the drying in step (1) is performed at a temperature of 105° C.;
the drying in step (1) is performed for 8 hours; and
the protective gas in step (2) is nitrogen gas, with a gas flow of 400-600 mL/min.

Assignees

• Univ South China Agricult

Inventors

• Xu Xiwei
• Yu Haipeng
• Jiang Enchen
• Zhang Fan
• Li Linghao
• Wang Hong
• Sun Yan

Classifications

• C10B57/08 Primary

  Non-mechanical pretreatment of the charge (C10L9/00 takes precedence), {e.g. desulfurization} · CPC title

• C07D307/46 Primary

  Doubly bound oxygen atoms, or two oxygen atoms singly bound to the same carbon atom · CPC title

• C10B53/02 Primary

  of cellulose-containing material (production of pyroligneous acid C10C5/00) · CPC title

• C10G1/042

  by the use of hydrogen-donor solvents · CPC title

• C10G32/02

  by electric or magnetic means · CPC title