Method for manufacturing gasoline particulate filter

Patent metadata

Field	Value
Publication number	US-12544739-B2
Application number	US-202318321390-A
Country	US
Kind code	B2
Filing date	May 22, 2023
Priority date	May 27, 2022
Publication date	Feb 10, 2026
Grant date	Feb 10, 2026

Abstract

A method for the manufacture of a gasoline particulate filter (GPF) for the treatment of an exhaust gas is disclosed. The method comprises (i) forming a washcoat slurry; (ii) coating a wall-flow filter substrate with the washcoat slurry to form a washcoated substrate; and (iii) calcining the washcoated substrate to form a gasoline particulate filter. The washcoat slurry comprises (a) a platinum group metal selected from the group consisting of Pt, Pd, Rh and mixtures thereof; (b) an oxygen storage capacity (OSC) material; and (c) a C2-C6 aliphatic amino acid.

First claim

The invention claimed is:

1 . A method for the manufacture of a gasoline particulate filter (GPF) for the treatment of an exhaust gas, the method comprising:
(i) forming a washcoat slurry; (ii) coating a wall-flow filter substrate with the washcoat slurry to form a washcoated substrate; and (iii) calcining the washcoated substrate to form a gasoline particulate filter; wherein the washcoat slurry comprises (a) a platinum group metal selected from the group consisting of Pt, Pd, Rh and mixtures thereof; (b) an oxygen storage capacity (OSC) material; and (c) a C 2 -C 6 aliphatic amino acid.

2 . The method of claim 1 , wherein the C 2 -C 6 aliphatic amino acid has the formula HO 2 C—(CH 2 ) n —NH 2 , wherein n is from 1 to 5.

3 . The method of claim 2 , wherein n is from 1 to 3.

4 . The method of claim 2 , wherein n is 2.

5 . The method of claim 4 , wherein the amount of the C 2 -C 6 aliphatic amino acid in the 30 washcoat slurry is from 1 to 50% wt % relative to the crucible solids in the washcoat slurry.

6 . The method of claim 4 , wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 2 to 40 wt % relative to the crucible solids in the washcoat slurry.

7 . The method of claim 4 , wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 5 to 30 wt % relative to the crucible solids in the washcoat slurry.

8 . The method of claim 4 ,
wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 5 to 30 wt % relative to the crucible solids in the washcoat slurry; wherein the OSC material comprises a cerium-zirconium mixed oxide nano sol with a mean particle size of less than 1 μm; and wherein the inorganic oxide support is a gamma-alumina having a mean particle size of from 1 to 10 μm.

9 . The method of claim 4 ,
wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 5 to 30 wt % relative to the crucible solids in the washcoat slurry; wherein the OSC material comprises a cerium-zirconium mixed oxide nano sol with a mean particle size of less than 1 μm; wherein the inorganic oxide support is a gamma-alumina having a mean particle size of from 2 to 8 μm.

10 . The method of claim 4 ,
wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 5 to 30 wt % relative to the crucible solids in the washcoat slurry; wherein the OSC material comprises a cerium-zirconium mixed oxide with a mean particle size of from 5 to 10 μm; and wherein the inorganic oxide support is a nano alumina with a mean particle size of less than 1 μm.

11 . The method of claim 1 , wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 1 to 50% wt % relative to the crucible solids in the washcoat slurry.

12 . The method of claim 1 , wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 2 to 40 wt % relative to the crucible solids in the washcoat slurry.

13 . The method of claim 1 , wherein the amount of the C 2 -C 6 aliphatic amino acid in the washcoat slurry is from 5 to 30 wt % relative to the crucible solids in the washcoat slurry.

14 . The method of claim 1 , wherein the washcoat slurry comprises Pt and Rh.

15 . The method of claim 1 , wherein the washcoat slurry comprises Pd and Rh.

16 . The method of claim 1 , wherein the OSC material comprises a mixed oxide of cerium and zirconium; a mixed oxide of cerium, zirconium, and aluminium; a mixed oxide of cerium, zirconium, and neodymium; or a mixed oxide of cerium, zirconium and praseodymium.

17 . The method of claim 1 , wherein the OSC material comprises a cerium-zirconium mixed oxide nano sol with a mean particle size of less than 1 μm.

18 . The method of claim 1 , wherein the washcoat slurry further comprises an inorganic oxide support.

19 . The method of claim 18 , wherein the inorganic oxide support comprises alumina.

20 . The method of claim 18 , wherein the inorganic oxide support comprises a gamma-alumina.

Assignees

• Johnson Matthey Plc

Inventors

• Benet Rajkumar Brenda
• Chavda Ketan
• Clowes Lucy
• Dunseath Olivia
• Walton Mark

Classifications

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/40

  characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77) · CPC title

• B01J35/56

  Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional [3D] monoliths · CPC title

• B01J37/088

  Decomposition of a metal salt · CPC title

• B01J37/0219

  the coating containing organic compounds · CPC title