Copper cha zeolite catalysts

Patent metadata

Field	Value
Publication number	US-2016101411-A1
Application number	US-201514973353-A
Country	US
Kind code	A1
Filing date	Dec 17, 2015
Priority date	Feb 27, 2007
Publication date	Apr 14, 2016
Grant date	—

Abstract

Zeolite catalysts and systems and methods for preparing and using zeolite catalysts having the CHA crystal structure are disclosed. The catalysts can be used to remove nitrogen oxides from a gaseous medium across a broad temperature range and exhibit hydrothermal stable at high reaction temperatures. The zeolite catalysts include a zeolite carrier having a silica to alumina ratio from about 15:1 to about 256:1 and a copper to alumina ratio from about 0.25:1 to about 1:1.

First claim

1 - 17 . (canceled)

18 . A catalyst comprising a copper ion-exchanged aluminosilicate zeolite having a CHA crystal structure, the zeolite having a mole ratio of silica to alumina from about 20 to about 40 and an atomic ratio of copper to aluminum from about 0.25 to about 0.50.

19 . The catalyst according to claim 18 , wherein the catalyst contains ion-exchanged copper and an amount of non-exchanged copper sufficient to maintain NOx conversion performance of the catalyst in an exhaust gas stream containing nitrogen oxides after hydrothermal aging of the catalyst.

20 . The catalyst according to claim 18 , wherein the mole ratio of silica to alumina is about 25 to about 40.

21 . The catalyst according to claim 18 , wherein the mole ratio of silica to alumina is about 25.

22 . The catalyst according to claim 18 , wherein the mole ratio of silica to alumina is about 26.

23 . The catalyst according to claim 18 , wherein the mole ratio of silica to alumina is about 27.

24 . The catalyst according to claim 18 , wherein the mole ratio of silica to alumina is about 28.

25 . The catalyst according to claim 18 , wherein the mole ratio of silica to alumina is about 29.

26 . The catalyst according to claim 19 , wherein the mole ratio of silica to alumina is about 30.

27 . The catalyst according to claim 19 , wherein the zeolite having the CHA structure is SSZ-13.

28 . The catalyst according to claim 18 , wherein the atomic ratio of copper to aluminum is about 0.30.

29 . The catalyst according to claim 18 , wherein the atomic ratio of copper to aluminum is about 0.33.

30 . The catalyst according to claim 18 , wherein the atomic ratio of copper to aluminum is about 0.38.

31 . The catalyst according to claim 18 , wherein the atomic ratio of copper to aluminum is about 0.44.

32 . The catalyst according to claim 18 , wherein the atomic ratio of copper to aluminum is about 0.46.

33 . The catalyst according to claim 18 , wherein the atomic ratio of copper to aluminum is about 0.40.

34 . The catalyst according to claim 18 , further comprising a binder.

35 . The catalyst according to claim 34 , wherein the binder is ZrO 2 .

36 . The catalyst according to claim 19 , wherein the zeolite contains at least about 2.00 weight percent copper, expressed as copper oxide.

37 . An exhaust gas treatment system comprising the catalyst of claim 18 and further comprising a catalyzed soot filter.

38 . The exhaust gas treatment system of claim 37 , wherein said catalyzed soot filter is upstream of said catalyst.

39 . The exhaust gas treatment system of claim 37 , further comprising a diesel oxidation catalyst.

40 . The exhaust gas treatment system of claim 39 , wherein the diesel oxidation catalyst is upstream of the catalyst comprising the zeolite having the CHA crystal structure.

41 . A catalyst article comprising a substrate having deposited thereon the catalyst according to claim 18 .

42 . The catalyst article according to claim 41 , wherein the substrate is metal or ceramic.

43 . The catalyst article according to claim 42 , wherein the substrate is a honeycomb substrate.

44 . The catalyst article according to claim 43 , wherein the honeycomb substrate is a flow through substrate.

45 . The catalyst article according to claim 43 , wherein the honeycomb substrate is a wall flow substrate.

Assignees

• Basf Corp

Inventors

• Bull Ivor
• Xue Wen-Mei
• Burk Patrick
• Boorse R Samuel
• Jaglowski William M
• Koermer Gerald Stephen
• Moini Ahmad
• Patchett Joseph A
• Dettling Joseph C
• Caudle Matthew Tyler

Classifications

• B01D2255/9155

  Wall flow filters · CPC title

• B01J23/8926

  Copper and noble metals · CPC title

• B01D53/9413

  Processes characterised by a specific catalyst · CPC title

• B01D2251/206

  Ammonium compounds · CPC title

• C01B39/46

  Other types characterised by their X-ray diffraction pattern and their defined composition {(C01B39/023, C01B39/026, C01B39/06 take precedence)} · CPC title