US 12,305,553 B2
Catalytic wall flow filter
Brenda Benet Rajkumar, Royston (GB); Fezile Lakadamyali, Wayne, PA (US); and John Turner, Royson (GB)
Assigned to Johnson Matthey Public Limited Company, London (GB)
Filed by Johnson Matthey Public Limited Company, London (GB)
Filed on Feb. 5, 2024, as Appl. No. 18/432,154.
Claims priority of provisional application 63/486,492, filed on Feb. 23, 2023.
Prior Publication US 2024/0287923 A1, Aug. 29, 2024
Int. Cl. F01N 3/035 (2006.01); B01D 53/94 (2006.01); B01J 23/44 (2006.01); B01J 23/46 (2006.01); B01J 23/63 (2006.01); B01J 35/00 (2024.01); F01N 3/10 (2006.01); F01N 3/28 (2006.01)
CPC F01N 3/035 (2013.01) [B01D 53/945 (2013.01); B01D 53/9477 (2013.01); B01J 23/44 (2013.01); B01J 23/464 (2013.01); B01J 23/63 (2013.01); B01J 35/19 (2024.01); F01N 3/101 (2013.01); F01N 3/2803 (2013.01); B01D 2255/1023 (2013.01); B01D 2255/1025 (2013.01); B01D 2255/407 (2013.01); B01D 2255/908 (2013.01); B01D 2255/9155 (2013.01); F01N 2330/30 (2013.01); F01N 2370/02 (2013.01); F01N 2510/0684 (2013.01)] 18 Claims
 
1. A catalytic wall-flow filter for exhaust gas from a gasoline engine, the catalytic wall-flow filter comprising:
a wall-flow filter substrate having porous walls and having a first face and a second face defining a longitudinal direction therebetween and first and second pluralities of channels extending in the longitudinal direction, wherein the first plurality of channels is open at the first face and closed at the second face, and wherein the second plurality of channels is open at the second face and closed at the first face;
a first TWC coating in the first plurality of channels, the first TWC coating comprising a first PGM composition, a first oxygen storage capacity (OSC) material, and a first inorganic support;
a second TWC coating in the second plurality of channels, the second TWC coating comprising a second PGM composition, a second OSC material, and a second inorganic support;
wherein the first PGM composition comprises rhodium in an amount of 50 to 95 wt % relative to the total weight of the first PGM composition;
wherein the second PGM composition comprises palladium in an amount of 90 to 99 wt % relative to the total weight of the second PGM composition;
wherein the first TWC coating is coated from the first face;
wherein the second TWC coating is coated from the second face;
wherein the first face is an inlet face and the second face is an outlet face of the catalytic wall-flow filter.