CPC B01D 53/945 (2013.01) [B01D 53/9468 (2013.01); B01J 21/066 (2013.01); B01J 23/10 (2013.01); B01J 23/464 (2013.01); B01J 23/63 (2013.01); B01J 35/19 (2024.01); B01J 35/56 (2024.01); F01N 3/035 (2013.01); F01N 3/101 (2013.01); F01N 3/28 (2013.01); F01N 3/2825 (2013.01); B01D 2255/1021 (2013.01); B01D 2255/1023 (2013.01); B01D 2255/1025 (2013.01); B01D 2255/2061 (2013.01); B01D 2255/2063 (2013.01); B01D 2255/2065 (2013.01); B01D 2255/2066 (2013.01); B01D 2255/20715 (2013.01); B01D 2255/2092 (2013.01); B01D 2255/407 (2013.01); B01D 2255/9022 (2013.01); B01D 2255/908 (2013.01); B01D 2255/9155 (2013.01); B01D 2258/014 (2013.01); F01N 2330/06 (2013.01); F01N 2330/30 (2013.01); F01N 2370/02 (2013.01); F01N 2510/06 (2013.01); F01N 2510/0684 (2013.01)] | 23 Claims |
1. A particulate filter for removing particles, carbon monoxide, hydrocarbons and nitrogen oxides from exhaust gas of a combustion engine fueled by a stoichiometric air-fuel mixture, the particulate filter comprises a wall-flow filter of length L and two different coatings Y and Z, wherein the wall-flow filter comprises channels E and channels A that extend in parallel between a first end and a second end of the wall-flow filter and are separated by porous walls which form surfaces OF and surfaces OA, respectively, and wherein the channels E are closed at the second end and the channels A are closed at the first end, wherein the coating Y is located in the channels E on the surfaces OF and extends from the first end of the wall-flow filter over a length (Ly) of 51 to 90% of the length L with a thickness between 5-250 μm and the coating Z is located in the porous walls and extends from the second end of the wall-flow filter over a length (Lz) of 60 to 100% of the length L such that from 10% to 49% of the porous walls of channels E are exposed as to enable exhaust gas contact with coating Y followed by exhaust gas flow to the exposed porous walls in channels E and into contact with coating Z, and wherein length Ly plus length Lz is 110 to 180% of length L and coating Y has a coating load of from 33 to 125 g/l, based on the volume of the wall flow filter, and coating Z has a coating load of from 33 to 125 g/l, based on the volume of the wall flow filter.
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