System and method for creating catalyst OBD limit parts for exhaust aftertreatment applications

Patent metadata

Field	Value
Publication number	US-9528420-B2
Application number	US-201414494312-A
Country	US
Kind code	B2
Filing date	Sep 23, 2014
Priority date	Sep 23, 2014
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

Catalyst diagnostic limit parts and methods for making catalyst diagnostic limit parts are disclosed. An exemplary catalyst diagnostic limit part includes a substrate and a washcoat coating the substrate. The washcoat includes an active catalyst and an inactive catalyst at a predetermined ratio of active catalyst to inactive catalyst so as to control the performance of the catalyst diagnostic limit part.

First claim

What is claimed is:

1. A method comprising:
identifying a predetermined amount of degradation of a catalyst to simulate by a catalyst diagnostic limit part;
preparing a washcoat slurry including a first amount of an active catalyst and a second amount of an inactive catalyst at a predetermined ratio of the first amount to the second amount so as to simulate the predetermined amount of degradation of the catalyst;
coating a substrate with the washcoat slurry; and
installing the coated substrate in a housing to form the catalyst diagnostic limit part;
wherein the predetermined ratio is no higher than 30%:70%.

2. The method of claim 1 , wherein the predetermined ratio is no higher than 25%:75%.

3. The method of claim 1 , further comprising thermally aging an active catalyst to produce the inactive catalyst.

4. The method of claim 1 , wherein the inactive catalyst includes a chemically-inert material.

5. The method of claim 4 , wherein the chemically-inert material includes un-exchanged zeolites.

6. The method of claim 1 , wherein the substrate has a length to diameter ratio of at least 0.33.

7. The method of claim 1 , wherein the substrate is fully coated by the washcoat slurry.

8. The method of claim 1 , wherein the catalyst diagnostic limit part is a diesel oxidation catalyst.

9. The method of claim 1 , wherein the catalyst diagnostic limit part is one of a selective catalytic reduction catalyst, a selective catalytic reduction catalyst on filter, and an ammonia oxidation catalyst.

10. The method of claim 1 , wherein the catalyst diagnostic limit part includes each of a diesel oxidation catalyst and a diesel particulate filter.

11. The method of claim 1 , wherein the substrate is a flow-through substrate.

12. The method of claim 1 , wherein the substrate is a wall-flow substrate.

Assignees

• Cummins Emission Solutions Inc

Inventors

• Liu Qiang
• Liu Yi
• Liu Zheng
• Harinath Arvind V
• Li Huiling

Classifications

• B01J37/0215

  Coating · CPC title

• F01N2550/02

  Catalytic activity of catalytic converters · CPC title

• F01N2510/068

  characterised by the distribution of the catalytic coatings · CPC title

• B01J29/76

  Iron group metals or copper · CPC title

• G01N31/10

  using catalysis · CPC title