CATALYTIC PRODUCT FOR EXHAUST GAS TREATMENT Russian patent published in 2022 - IPC B01J29/72 B01J35/04 B01D53/94 

FIELD: catalytic products.

SUBSTANCE: catalytic product is designed to treat exhaust gases generated during combustion. The catalytic product contains a flowing honeycomb substrate with channel walls, a first NH₃-SCR catalyst composition, and a second NH₃-SCR catalyst composition. The first NH₃-SCR catalyst composition is deposited on and/or inside the channel walls in the first zone. The second NH₃-SCR catalyst composition is applied to and/or within the walls of the channels in the second zone, provided that the first zone is located upstream of the second zone and the first and second zones are adjacent to each other or at least partially overlap. In this case, the first NH₃-SCR catalyst composition contains a first molecular sieve containing copper, with an atomic ratio of copper to aluminum from about 0.1 to about 0.375, and the second composition of the NH₃-SCR catalyst contains a second molecular sieve containing copper, with an atomic ratio of copper to aluminum from about 0.3 to about 0.6. The first molecular sieve containing copper has a lower concentration of copper compared to the second molecular sieve containing copper. Also, the first zone extends from the inlet side to the first end point located at a distance of about 10 to about 40 percent of the axial length, and the second zone is about 20 to about 90 percent of the axial length. In this case, the first and second zones are adjacent to each other or overlap by less than 90 percent of the axial length.

EFFECT: ensuring high NO_x conversion (in particular NO and NO₂) and N₂ selectivity in the SCR process.

15 cl, 11 dwg