Synergized PGM Catalyst Systems Including Rhodium for TWC Application

Patent metadata

Field	Value
Publication number	US-2016167024-A1
Application number	US-201414572200-A
Country	US
Kind code	A1
Filing date	Dec 16, 2014
Priority date	Dec 16, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

Synergized Platinum Group Metals (SPGM) catalyst system for TWC application is disclosed. Disclosed SPGM catalyst system may include a washcoat that includes Cu—Mn spinel structure, supported on doped ZrO 2 , and an overcoat that includes PGM, such as Rhodium (Rh) supported on carrier material oxides, such as alumina. SPGM catalyst system shows significant improvement in nitrogen oxide reduction performance under lean and also rich operating conditions. Furthermore, disclosed SPGM catalyst systems are found to have enhanced fresh and aged catalytic activity compared to PGM catalyst system, showing that there is a synergistic effect between PGM catalyst, such as Rh, and Cu—Mn spinel within disclosed SPGM catalyst system, which help in activity and thermal stability of disclosed SPGM catalyst.

First claim

1 . A synergized platinum group metals (SPGM) catalyst system comprising:
a) an overcoat comprising a platinum group metal (PGM) catalyst comprising rhodium supported on a carrier material oxide; b) a washcoat comprising a Cu—Mn spinel supported on a support oxide; and c) a substrate.

2 . The SPGM catalyst system of claim 1 , wherein the substrate is ceramic.

3 . The SPGM catalyst system of claim 1 , wherein the carrier oxide material is selected from the group consisting of aluminum oxide, doped aluminum oxide, zirconium oxide, doped zirconia, titanium oxide, tin oxide, silicon dioxide, zeolite, and mixtures thereof.

4 . The SPGM catalyst system of claim 1 , wherein the carrier material oxide is aluminum oxide.

5 . The SPGM catalyst system of claim 1 , wherein the Cu—Mn spinel is according to the formula Cu x Mn 3-x O 4 .

6 . The SPGM catalyst system of claim 1 , wherein the Cu—Mn spinel is CuMn 2 O 4 .

7 . The SPGM catalyst system of claim 1 , wherein the support oxide is a doped ZrO 2 support oxide.

8 . The SPGM catalyst system of claim 1 , wherein the doped ZrO 2 support oxide is a Niobium-zirconia support oxide.

9 . The SPGM catalyst system of claim 1 , wherein the rhodium is about 1 g/ft 3 of rhodium.

10 . The SPGM catalyst system of claim 1 , wherein the SPGM catalyst system is hydrothermally aged.

11 . The SPGM catalyst system of claim 10 , wherein the hydrothermal aged system was heated at about 900° C. for about four hours.

12 . The SPGM catalyst system of claim 1 , wherein the SPGM catalyst system is fuel cut aged.

13 . The SPGM catalyst system of claim 12 , wherein the fuel cut aged system was heated at about 800° C. for about twenty hours.

14 . The SPGM catalyst system of claim 2 , wherein the ceramic is ceramic foam.

15 . The SPGM catalyst system of claim 1 , wherein the substrate is a honeycomb structure.

16 . The SPGM catalyst system of claim 1 , wherein the substrate is a foam.

17 . The SPGM catalyst system of claim 16 , wherein the foam is selected from the group consisting of a ceramic foam, a metallic foam, a reticulated foam, and combinations thereof.

18 . The SPGM catalyst system of claim 1 , wherein the substrate is a metallic material, refractive material, or a combination thereof.

19 . The SPGM catalyst system of claim 1 , wherein the PGM catalyst further comprises palladium, platinum, or the combination of palladium and platinum.

20 . The SPGM catalyst system of claim 1 , wherein the SPGM catalyst system a) reduces nitrogen oxide to nitrogen and oxygen, b) oxidizes carbon monoxide to carbon dioxide, and c) oxidizes unburnt hydrocarbons to carbon dioxide and water.

21 . A synergized platinum group metals (SPGM) catalyst system comprising:
a) an overcoat comprising a platinum group metal (PGM) catalyst comprising rhodium supported on aluminum oxide; b) a washcoat comprising a CuMn 2 O 4 spinel supported on a doped ZrO 2 support oxide; and c) a ceramic substrate.

22 . A method of decreasing pollutants comprising applying exhaust to a synergized platinum group metals (SPGM) catalyst system comprising:
a) an overcoat comprising a platinum group metal (PGM) catalyst comprising rhodium supported on a carrier material oxide; b) a washcoat comprising a Cu—Mn spinel supported on a support oxide; and c) a substrate.

23 . The method of claim 22 , wherein the exhaust is from an engine-equipped machine.

24 . The method of claim 22 , wherein the engine-equipped machine is an automobile, airplane, train, all-terrain vehicle, boat, or mining equipment.

25 . The method of claim 22 , wherein the exhaust is from a utility plant, processing plant, or manufacturing plant.

26 . The method of claim 22 , wherein the SPGM catalyst system converts about 72% of nitrogen oxide.

27 . The SPGM catalyst system of claim 22 , wherein the substrate is ceramic.

28 . The SPGM catalyst system of claim 22 , wherein the carrier oxide material is selected from the group consisting of aluminum oxide, doped aluminum oxide, zirconium oxide, doped zirconia, titanium oxide, tin oxide, silicon dioxide, zeolite, and mixtures thereof.

29 . The SPGM catalyst system of claim 22 , wherein the carrier material oxide is aluminum oxide.

30 . The SPGM catalyst system of claim 22 , wherein the Cu—Mn spinel is according to the formula Cu x Mn 3-x O 4 .

31 . The SPGM catalyst system of claim 22 , wherein the Cu—Mn spinel is CuMn 2 O 4 .

32 . The SPGM catalyst system of claim 22 , wherein the support oxide is a doped ZrO 2 support oxide.

33 . The SPGM catalyst system of claim 22 , wherein the doped ZrO 2 support oxide is a Niobium-zirconia support oxide.

34 . The SPGM catalyst system of claim 22 , wherein the rhodium is about 1 g/ft 3 of rhodium.

35 . The SPGM catalyst system of claim 22 , wherein the SPGM catalyst system is hydrothermally aged.

36 . The SPGM catalyst system of claim 35 , wherein the hydrothermal aged system was heated at about 900° C. for about four hours.

37 . The SPGM catalyst system of claim 22 , wherein the SPGM catalyst system is fuel cut aged.

38 . The SPGM catalyst system of claim 37 , wherein the fuel cut aged system was heated at about 800° C. for about twenty hours.

39 . The SPGM catalyst system of claim 23 , wherein the ceramic is ceramic foam.

40 . The SPGM catalyst system of claim 22 , wherein the substrate is a honeycomb structure.

41 . The SPGM catalyst system of claim 22 , wherein the substrate is a foam.

42 . The SPGM catalyst system of claim 41 , wherein the foam is selected from the group consisting of a ceramic foam, a metallic foam, a reticulated foam, and combinations thereof.

43 . The SPGM catalyst system of claim 22 , wherein the substrate is a metallic material, refractive material, or a combination thereof.

44 . The SPGM catalyst system of claim 22 , wherein the PGM catalyst further comprises palladium, platinum, or the combination of palladium and platinum.

45 . The SPGM catalyst system of claim 22 , wherein the SPGM catalyst system a) reduces nitrogen oxide to nitrogen and oxygen, b) oxidizes carbon monoxide to carbon dioxide, and c) oxidizes unburnt hydrocarbons to carbon dioxide and water.

Assignees

• Nazarpoor Zahra
• Golden Stephen J
• Clean Diesel Tech Inc

Inventors

• Nazarpoor Zahra
• Golden Stephen J

Classifications

• B01J21/04

  Alumina · CPC title

• B01J23/8892 Primary

  Manganese · CPC title

• B01J37/0215

  Coating · CPC title

• B01J37/0228

  in several steps · CPC title

• B01J23/005

  Spinels · CPC title