Ruthenium impregnated ceria catalyst

Patent metadata

Field	Value
Publication number	US-10895183-B2
Application number	US-201916259267-A
Country	US
Kind code	B2
Filing date	Jan 28, 2019
Priority date	Jul 29, 2016
Publication date	Jan 19, 2021
Grant date	Jan 19, 2021

Abstract

The present disclosure generally provides low-temperature nitrogen oxides (NO x ) adsorbers used in the treatment of a NO x -containing exhaust gas stream and to methods of preparing and using the same. In particular, the NO x adsorber composition includes an active metal and a metal oxide support, wherein the metal oxide support includes greater than 50% by weight ceria based on the total weight of the NO x adsorber composition, and wherein the active metal includes about 0.01% to about 5% by weight ruthenium based on the total weight of the NO x adsorber composition.

First claim

That which is claimed:

1. A low-temperature NO x adsorber composition comprising:
an active metal and a metal oxide support, wherein the metal oxide support comprises greater than 50% by weight ceria based on the total weight of the NO x adsorber composition, and wherein the active metal comprises about 0.01% to about 5% by weight ruthenium based on the total weight of the NO x adsorber composition, and wherein the metal oxide support further comprises Pr 6 O 11 or Gd 2 O 3 in an amount of about 0.1% to about 10% by weight, based on the total weight of the NO x adsorber composition.

2. The low-temperature NO x adsorber composition of claim 1 , wherein the low-temperature NO x adsorber composition is substantially free of barium or zeolite.

3. The low-temperature NO x adsorber composition of claim 1 , wherein the metal oxide support comprises greater than 90% by weight ceria based on the total weight of the NO x adsorber.

4. The low-temperature NO x adsorber composition of claim 1 , wherein the NO x adsorber composition comprises a surface concentration of active Ru ions of at least 0.5% by weight based on the total weight of the NO x adsorber composition.

5. The low-temperature NO x adsorber composition of claim 1 , wherein the NO x adsorber composition adsorbs NO from the exhaust gas stream at a temperature of about 50° C. to about 200° C. in an amount of at least 30-60% by weight based on the total amount of NO present in the exhaust gas stream.

6. The low-temperature NO x adsorber composition of claim 1 , wherein the NO x adsorber composition oxidizes NO present in the exhaust gas steam to NO 2 at a temperature ranging from about 300° C. to about 600° C.

7. The low-temperature NO x adsorber composition of claim 1 , wherein the NO x adsorber composition releases NO back into the exhaust gas stream at a temperature of about 170° C. to about 300° C. in an amount of at least 55 to about 100% by weight based on the total amount of NO adsorbed onto the NO x adsorber composition.

8. The low-temperature NO x adsorber composition of claim 1 , wherein the NO x adsorber composition is substantially free of any additional active metal.

9. The low-temperature NO x adsorber composition of claim 1 , wherein the NO x adsorber composition is comprised in a lean NO x trap.

10. The catalyst article of claim 9 , further comprising a second catalyst composition, wherein the second catalyst composition comprises a DOC catalyst composition or a LNT catalyst composition; and
wherein the second catalyst composition is layered or zoned on the substrate carrier with the NO x adsorber catalyst composition.

11. The catalyst article of claim 10 , wherein the second catalyst composition is disposed directly on the substrate carrier.

12. A catalyst article comprising a catalyst substrate carrier having a plurality of channels adapted for gas flow and a low temperature NO x adsorber composition according to claim 1 positioned to contact an exhaust gas passing through each channel.

13. The catalyst article of claim 12 , wherein the substrate carrier is a metal or ceramic honeycomb.

14. The catalyst article of claim 13 , wherein the honeycomb is a wall flow filter substrate or a flow through substrate.

15. The catalyst article of claim 13 , wherein the low temperature NO x adsorber composition is applied to the substrate carrier with a loading of at least about 0.5 g/in 3 .

16. The catalyst article of claim 12 , wherein the active metal is present in an amount of about 10 to about 200 g/ft 3 .

17. An exhaust gas treatment system comprising a low-temperature NO x adsorber composition according to claim 1 and an SCR catalyst disposed downstream from an internal combustion engine.

18. The exhaust gas treatment system of claim 17 , wherein the low-temperature NO x adsorber composition is present on a substrate carrier positioned upstream of the SCR catalyst.

19. The exhaust gas treatment system of claim 17 , wherein the low-temperature NO x adsorber composition and SCR catalyst are disposed on the same substrate carrier.

20. The exhaust gas treatment system of claim 17 , wherein the internal combustion engine is a gasoline or a diesel engine.

Assignees

• Basf Corp

Inventors

• Gerlach Olga
• Wei Xinyi
• Sundermann Andreas
• Schulman Emily
• Roth Stanley A

Classifications

• Y02C20/10

  of nitrous oxide (N2O) · CPC title

• F01N2570/145

  Dinitrogen oxide · CPC title

• F01N2250/12

  absorption or adsorption, and catalytic conversion · CPC title

• B01D2255/2066

  Praseodymium · CPC title

• B01D2255/2065

  Cerium · CPC title