Active perovskite-type catalysts stable to high temperature aging for gasoline exhaust gas applications

Patent metadata

Field	Value
Publication number	US-2020306730-A1
Application number	US-202016832018-A
Country	US
Kind code	A1
Filing date	Mar 27, 2020
Priority date	Mar 29, 2019
Publication date	Oct 1, 2020
Grant date	—

Abstract

Compositions, articles, and methods related to a three-way-catalyst composition comprising a perovskite-type compound of formula (I): LazB1-qB′qO3±δ or formula (II): [BOx]y:[LazBO3±δ]1-y and a non-redox active component; wherein B or B′ is Fe, Mn, Co, Ni, Cu, Ti, or Zr; q is in a range from about 0 to about 0.5; x is from about 1 to about 2.5; y is from about 1 to about 30 wt %; z is about 0.6 to about 1.1; δ is in a range from about 0 to about 0.6.

First claim

1 . A three-way catalyst composition comprising a perovskite-type compound of formula (I): La z B 1-q B′ q O 3±δ or formula (II): [BO x ] y : [La z BO 3±δ ] 1-y and a non-redox active component; wherein
B or B′ is Fe, Mn, Co, Ni, Cu, Ti, or Zr;
q is in a range from about 0 to about 0.5;
δ is in a range from about 0 to about 0.6;
x is from about 1 to about 2.5;
y is from about 1 to about 30 wt %;
z is about 0.6 to about 1.1.

2 . The three-way catalyst composition of claim 1 , wherein the perovskite-type compound is the compound of formula (I): La z BO 3±δ .

3 . The three-way catalyst composition of claim 2 , wherein B is Fe.

4 . The three-way catalyst composition of claim 2 , wherein B is Mn.

5 . The three-way catalyst composition of claim 1 , wherein the perovskite-type compound is the compound of formula (II): [BO x ] y : [La z BO 3±δ ] 1-y .

6 . The three-way catalyst composition of claim 5 , wherein B is Mn.

7 . The three-way catalyst composition of claim 1 , wherein the non-redox active component comprises an oxide.

8 . The three-way catalyst composition of claim 1 , wherein the non-redox active component comprises alumina.

9 . The three-way catalyst composition of claim 1 , wherein the non-redox active component comprises ZrO 2 .

10 . The three-way catalyst composition of claim 9 , wherein the ZrO 2 is doped.

11 . The three-way catalyst composition of claim 1 , wherein the catalyst is substantially free of platinum group metals.

12 . The three-way catalyst composition of claim 1 , wherein the catalyst is free of platinum group metals.

13 . The three-way catalyst composition of claim 1 , wherein the perovskite-type compound is present in an amount of about 5 wt % to about 75 wt % of the catalyst composition.

14 . The three-way catalyst composition of claim 1 , wherein the non-redox active component is present in an amount of about 25 wt % to about 95 wt % of the catalyst composition.

15 . The three-way catalyst composition of claim 1 , wherein the perovskite-type compound and the non-redox active component are present in a weight ratio of about 0.5:1 to about 3:1.

16 . (canceled)

17 . The three-way catalyst composition of claim 1 , wherein the perovskite-type compound has high surface area of at least 40 m 2 /g.

18 . A catalyst article for treating exhaust gas, comprising:
a. a substrate; and b. the three-way-catalyst composition of claim 1 .

19 . A method of treating an exhaust gas from an internal combustion engine, comprising contacting the exhaust gas with a catalyst article comprising a substrate and the three-way-catalyst composition of claim 1 .

20 . The method of claim 19 , wherein the three-way-catalyst composition provides:
(1) a fresh NO conversion at 500-600° C., and (2) an aged NO conversion at 500-600° C. after aging the catalyst at a temperature of at least 700° C. for 20 hours in the presence of steam, wherein a delta between the fresh NO conversion and the aged NO conversion is a decrease of less than 20%.

21 . (canceled)

22 . The method of claim 19 , wherein the three-way-catalyst composition provides:
(1) a fresh HC or CO conversion at 500° C., and (2) an aged HC or CO conversion at 500° C. after aging the catalyst at a temperature of at least 700° C. for 20 hours in the presence of steam, wherein a delta between the fresh HC or CO conversion and the aged HC or CO conversion is a decrease of less than 50%.

23 . (canceled)

Assignees

• Johnson Matthey Plc

Inventors

• Nagaoka Shuhei
• Simmance Kerry
• Pascui Andrea Eva
• Price Emily

Classifications

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J35/45

  Nanoparticles · CPC title

• B01J35/733

  Perovskite-type · CPC title