CATALYTIC FILTER WITH FLOW WALLS WITH CATALYST FOR NEUTRALIZING AMMONIA SLIP Russian patent published in 2021 - IPC B01D53/94 F01N3/35 

FIELD: exhaust gas purification.

SUBSTANCE: invention is intended for purifying exhaust gases. A catalytic monolithic filter with flow walls for use in an exhaust purifying system has the first end surface, the second end surface, a filter length determined by the distance from the first end surface to the second end surface, a longitudinal direction between the first end surface and the second end surface, and the first and second sets of channels extending in the longitudinal direction. The first set of channels is open on the first end surface and closed on the second end surface, and the second set of channels is open on the second end surface and closed on the first end surface. The monolithic filter contains porous substrate having surfaces that form channels, and having the first zone extending in the longitudinal direction from the first end surface to the second end surface for a distance less than the filter length, and the second zone extending in the longitudinal direction from the second end surface to the first end surface and extending in the longitudinal direction for a distance less than the filter length. The first zone contains the first SCR catalyst distributed throughout porous substrate. The second zone contains an ammonia oxidation catalyst distributed throughout porous substrate and the second SCR catalyst located in a layer that covers surfaces in the second zone of porous substrate. The exhaust purifying system, a method for manufacturing the catalytic monolithic filter and a method for purifying the flow of combustion exhaust gases are also described.

EFFECT: technical result is that the invention provides improved NO_x conversion over a wide temperature range with a similar NH₃ conversion and reduced N₂O formation.

27 cl, 11 dwg, 2 ex, 1 tbl