Optimization of Zero-PGM washcoat and overcoat loadings on metallic substrate

• US 9,545,626 B2
• Filed: 07/12/2013
• Issued: 01/17/2017
• Est. Priority Date: 07/12/2013
• Status: Active Grant

• Current Assignee: Clean Diesel Technologies, Inc.
• Original Assignee: Clean Diesel Technologies, Inc.
• Inventors: Nazarpoor, Zahra, Kitazumi, Sen, Ngo, Johnny T.
• Primary Examiner(s): Dunn, Colleen
• Assistant Examiner(s): Soliman, Haytham
• Application Number:
  US13/941,015
• Publication Number:
  US 20150018203A1
• Time in Patent Office: 1,285 Days
• Field of Search: 502/355, 502/341, 502/331, 502/100, 502/350, 502/340, 502/304, 502/349, 502/352, 502/232, 502/319, 502/321, 502/320, 502/322, 502/60, 502/324, 502/332, 502/337, 502/338, 502/336, 502/346, 502/353, 502/348, 502/354, 423/210
• US Class Current: 1/1
• CPC Class Codes: B01D 2255/104 Silver
• CPC Class Codes: B01D 2255/2065 Cerium
• CPC Class Codes: B01D 2255/20707 Titanium
• CPC Class Codes: B01D 2255/20715 Zirconium
• CPC Class Codes: B01D 2255/20761 Copper
• CPC Class Codes: B01D 2255/65 Catalysts not containing noble metals
• CPC Class Codes: B01D 2255/9022 Two layers
• CPC Class Codes: B01D 2255/908 O2-storage component incorporated in the catalyst
• CPC Class Codes: B01D 53/944 Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts three-way-catalysts [TWC] B01D53/9445
• CPC Class Codes: B01J 23/50 Silver
• CPC Class Codes: B01J 23/72 Copper
• CPC Class Codes: B01J 23/83 with rare earths or actinides
• CPC Class Codes: B01J 37/0244 Coatings comprising several layers

Abstract

The present disclosure refers to a plurality of process employed for optimization of Zero-PGM washcoat and overcoat loadings on metallic substrates. According to an embodiment a substantial increase in conversion of HC and CO may be achieved by optimizing the total washcoat and overcoat loadings of the catalyst. According to another embodiment, the present disclosure may provide solutions to determine the optimum total washcoat and overcoat loadings for minimizing washcoat adhesion loss. As a result, may increase the conversion of HC and CO from discharge of exhaust gases from internal combustion engines, optimizing performance of Zero-PGM catalyst systems.

Claims

1. A method for optimizing a catalytic system, comprising:

providing a catalyst system, comprising;

a substrate;

a washcoat suitable for deposition on the substrate, comprising at least one first oxide solid comprising alumina and at least one first zero platinum group catalyst comprising silver; and

an overcoat suitable for deposition on the substrate, comprising at least one second oxide solid selected from the group consisting of a carrier material oxide, at least one second zero platinum group catalyst comprising one selected from the group consisting of copper oxide, ceria, and combinations thereof;

wherein the amount of the washcoat loading is about 120 g/L and the amount of the overcoat loading is about 100 g/L.

2. The method according to claim 1, wherein the at least one first zero platinum metal group catalyst comprises about 5.5 g/L of silver.

3. The method according to claim 1, wherein at least one second zero platinum metal group catalyst comprises about 6.5 g/L of copper oxide.

4. The method according to claim 1, wherein the washcoat adhesion loss is about 0% to about less than 2%.

5. The method according to claim 1, wherein the washcoat adhesion loss is less than about 2%.

6. The method according to claim 1, wherein the washcoat adhesion loss is less than 2.0%.

7. The method according to claim 1, wherein the washcoat adhesion loss is less than 1.0%.

8. The method according to claim 1, wherein the substrate is metallic.

9. The method according to claim 1, wherein the overcoat further comprises at least one oxygen storage material.

10. The method according to claim 1, wherein the carrier material oxide is selected from the group consisting of CeO₂, ZrO₂, TiO₂, and combinations thereof.

11. The method according to claim 1, wherein the at least one second zero platinum group catalyst comprises copper oxide and ceria.

12. The method according to claim 1, wherein the overcoat further comprises at least one oxygen storage material comprising cerium, zirconium, neodymium, and praseodymium.

13. The method according to claim 1, wherein at least one second zero platinum metal group catalyst comprises about 7.8 g/L of ceria.

14. The method according to claim 1, wherein the at least one first zero platinum metal group catalyst comprises about 1% by weight to about 20% by weight of silver.