US 12,246,306 B2
Catalyst for reducing nitrogen oxides
Badr Bassou, Frankfurt (DE); and Anke Woerz, Frankfurt (DE)
Assigned to UMICORE AG & CO. KG, Hanau-Wolfgang (DE)
Appl. No. 17/776,180
Filed by UMICORE AG & CO. KG, Hanau-Wolfgang (DE)
PCT Filed Nov. 18, 2020, PCT No. PCT/EP2020/082489
§ 371(c)(1), (2) Date May 11, 2022,
PCT Pub. No. WO2021/099361, PCT Pub. Date May 27, 2021.
Claims priority of application No. 19210276 (EP), filed on Nov. 20, 2019.
Prior Publication US 2022/0401920 A1, Dec. 22, 2022
Int. Cl. B01J 21/04 (2006.01); B01J 23/58 (2006.01); B01J 23/63 (2006.01); B01J 29/06 (2006.01); B01J 29/068 (2006.01); B01J 37/02 (2006.01); F01N 3/20 (2006.01)
CPC B01J 21/04 (2013.01) [B01J 23/58 (2013.01); B01J 23/63 (2013.01); B01J 29/068 (2013.01); F01N 3/2066 (2013.01); B01J 37/0246 (2013.01)] 9 Claims
 
1. A catalyst comprising a carrier substrate of length L, which is a flow-through substrate, and at least two washcoat layers A and B wherein
washcoat layer A comprises
alumina in an amount of 50 to 80 g/L, based on the volume of the carrier substrate;)
ceria in an amount of 100 to 130 g/L, based on the volume of the carrier substrate;
a composite material of ceria and alumina which comprises alumina in an amount of 5 to 95 wt %, based on the weight of the composite material in an amount of 10 to 80 g/L, based on the volume of the carrier substrate;
magnesium oxide and/or barium oxide in an amount of 15 to 20 g/L, based on the volume of the carrier substrate; and
platinum and palladium in a weight ratio of 1:1 to 12:1;
washcoat layer B comprises a zeolite of the structural type ABW, AEI, AFX, BEA, CHA, ERI, ESV, FAU, FER, KFI, LEV, LTA, MFI, MWW, SOD or STT and palladium, wherein the palladium is present as (i) a palladium cation in the zeolite structure and/or (ii) is present as either or both of a palladium metal or a palladium oxide located in, on, or both in and on the zeolite structure; and
wherein washcoat layer A is arranged directly on the carrier substrate and washcoat layer B is arranged directly on washcoat layer A.