SELECTIVE CATALYTIC REDUCTION ON N2O

• US 20090011927A1
• Filed: 09/11/2008
• Published: 01/08/2009
• Est. Priority Date: 03/12/2001
• Status: Active Grant

• Current Assignee: BASF Corporation (BASF SE)
• Original Assignee: BASF Corporation (BASF SE)
• Inventors: Mack, Stanley S., CHEN, James M., Durilla, Michael, Tran, Pascaline H.
• Granted Patent: US 7,951,742 B2
• Time in Patent Office: Days
• US Class Current: 502/66
• CPC Class Codes: B01D 2257/402 Dinitrogen oxide
• CPC Class Codes: B01D 53/8625 Nitrogen oxides
• CPC Class Codes: Y02C 20/10 of nitrous oxide (N2O)

Abstract

A gas stream containing nitrous oxide and ammonia is contacted with a catalyst composition containing a zeolite. N₂O is reduced to N₂ and H₂O at low temperatures in a highly efficient manner. Ammonia-mediated reduction of nitrous oxide can be effectuated from gas streams having N₂O concentrations as low as 1%. The gas stream may also contact a catalytic composition selective for the reduction of NO_x. In this way, N₂O and NO_x treatment may be effectuated in a single process stream.

Claims

1-16. -16. (canceled)

17. A catalyst composition for ammonia-mediated removal of N₂O from a gas stream comprising a catalyst selective for the reduction of N₂O.

18-21. -21. (canceled)

22. A catalyst composition for ammonia-mediated N₂O and NO_x reduction comprising at least two zones, at least one of the zones comprising a catalyst material selective for the reduction of NO_x and at least one other zone comprising a catalyst material selective for the reduction of N₂O.

23. A catalyst composition as recited in claim 22, wherein at least two zones have the same catalyst composition.

24. A catalyst composition as recited in claim 22, wherein the catalyst composition has two zones, each having the same catalyst composition.