Low washcoat loading single layer catalysts for gasoline exhaust gas applications
A three-way catalyst article, and its use in an exhaust system for internal combustion engines, is disclosed. The catalyst article for treating exhaust gas comprising: a substrate; and a single catalyst layer deposited directly on the substrate; wherein the single catalyst layer comprises a first platinum group metal (PGM) component, an oxygen storage component (OSC) material, and an inorganic oxide; and wherein the single catalyst layer has a total washcoat loading of less than 2.4 g/in 3 .
1. A catalyst article for treating exhaust gas comprising:
a substrate; and
a single catalyst layer deposited directly on the substrate;
wherein the single catalyst layer comprises a first platinum group metal (PGM) component, an oxygen storage component (OSC) material, and an inorganic oxide;
wherein the single catalyst layer has a total washcoat loading of no greater than 1.4 g/in 3 ;
wherein the OSC material loading in the single catalyst layer is less than 1.2 g/in 3 ; and
wherein the substrate is a flow-through monolith.
2. The catalyst article of claim 1 , wherein the total washcoat loading of the single catalyst layer is no greater than 1.2 g/in 3 .
3. The catalyst article of claim 1 , wherein the first PGM component is selected from the group consisting of platinum, palladium, rhodium, and a mixture thereof.
4. The catalyst article of claim 1 , wherein the first PGM component is rhodium.
5. The catalyst article of claim 4 , wherein the rhodium loading is ranged from 0.05-2 wt. %, based on the total weight of the single catalyst layer.
6. The catalyst article of claim 1 , wherein the OSC material loading in the single catalyst layer is no greater than 1.0 g/in 3 .
7. The catalyst article of claim 1 , wherein the OSC material is selected from the group consisting of cerium oxide, a ceria-zirconia mixed oxide, and an alumina-ceria-zirconia mixed oxide.
8. The catalyst article of claim 7 , wherein the OSC material is the ceria-zirconia mixed oxide.
9. The catalyst article of claim 8 , wherein the ceria-zirconia mixed oxide has a molar ratio of zirconia to ceria at least 1:1.
10. The catalyst article of claim 1 , wherein the inorganic oxide is selected from the group consisting of alumina, lanthanide-stabilized alumina, alkaline earth stabilized alumina, silica, aluminosilicates, a magnesia/alumina composite oxide, titania, niobia, tantalum oxides, neodymium oxide, yttrium oxide, lanthanides, and mixed oxides or composite oxides thereof.
11. The catalyst article of claim 10 , wherein the inorganic oxide is alumina, a lanthanide-stabilized alumina, or a magnesia/alumina composite oxide.
12. The catalyst article of claim 1 , wherein the OSC material and the inorganic oxide has a weight ratio of no greater than 10:1.
13. The catalyst article of claim 1 , wherein the single catalyst layer further comprises a second PGM component.
14. The catalyst article of claim 13 , wherein the second PGM component is selected from the group consisting of platinum, palladium, rhodium, and a mixture thereof.
15. The catalyst article of claim 14 , wherein the first PGM component is rhodium and the second PGM component is palladium.
16. The catalyst article of claim 15 , wherein the rhodium component and the palladium component have a weight ratio of from 10:1 to 1:10.
17. The catalyst article of claim 4 , wherein the single catalyst layer is essentially free of PGM metals other than the rhodium component.
18. The catalyst article of claim 1 , wherein the catalyst article does not further comprise any additional layer.
19. An emission treatment system for treating a flow of a combustion exhaust gas comprising the catalyst article of claim 1 .
20. The emission treatment system of claim 19 , further comprises a second catalyst article.
21. The emission treatment system of claim 20 , wherein the second catalyst article comprises a TWC catalyst.
22. The emission treatment system of claim 20 , wherein the second catalyst article is upstream of the catalyst article.
23. The emission treatment system of claim 20 , wherein the second catalyst article and the catalyst article are close-coupled.
24. A method of treating an exhaust gas from an internal combustion engine comprising contacting the exhaust gas with the catalyst article of claim 1 .
25. A method of treating an exhaust gas from an internal combustion engine comprising contacting the exhaust gas with the emission treatment system of claim 19 .
26. The catalyst article of claim 1 , wherein the total washcoat loading of the single catalyst layer is no greater than 1.0 g/in 3 .
27. The catalyst article of claim 1 , wherein the OSC material loading in the single catalyst layer is no greater than 0.8 g/in 3 .