Back to results
US 10,369,548 B2Granted
Catalyzed soot filter
AssigneeBASF SE
InventorsGerd Grubert, Alfred H. Punke, Torsten Neubauer, Marcus Hilgendorff, Chung-Zong Wan, Yuejin Li, Matthew Caudle
Life of this patent
Estimating the term…
Abstract
A catalyzed soot filter, in particular for the treatment of Diesel engine exhaust, comprises a coating design which ensures soot particulates filtration, assists the oxidation of carbon monoxide (CO), and produces low H2S emissions during normal engine operations and regeneration events.
Claims18
A catalyzed soot filter, comprising
- a wall flow substrate comprising an inlet end, an outlet end, a substrate axial length extending between the inlet end and the outlet end, and a plurality of passages defined by internal walls of the wall flow filter substrate;
- wherein the plurality of passages comprise inlet passages having an open inlet end and a closed outlet end, and outlet passages having a closed inlet end and an open outlet end;
- wherein the internal walls of the inlet passages comprise an inlet coating comprising at least one layer, and the inlet coating extends from the inlet end to an inlet coating end, thereby defining an inlet coating length, wherein the inlet coating length is x % of the substrate axial length, wherein x is from 25 to 100;
- and
- wherein the internal walls of the outlet passages comprise an outlet coating comprising at least one layer, and the outlet coating extends from the outlet end to an outlet coating end, thereby defining an outlet coating length, wherein the outlet coating length is y % of the substrate axial length, wherein y is from 25 to 100;
- wherein the inlet coating length defines an upstream zone of the catalyzed soot filter and the outlet coating length defines a downstream zone of the catalyzed soot filter;
- wherein the wall flow substrate comprises at least one layer comprising at least one oxidation catalyst and at least one layer comprising at least one H2S suppressing material, wherein the H2S suppressing material comprises CuO in the tenorite phase;
- wherein
- the at least one oxidation catalyst and the at least one H2S suppressing material are separated by the internal walls of the wall flow filter substrate;
- the total coating length is x+y, and x+y is greater than or equal to 150 and
- wherein the inlet coating comprises the H2S suppressing material, and the outlet coating comprises the at least one oxidation catalyst.
8 more elements
A process for manufacturing a catalyzed soot filter comprising:
- (i) providing a wall flow substrate comprising an inlet end, and outlet end, a substrate axial length extending between the inlet end and the outlet end, and a plurality of passages defined by the internal walls of the wall flow substrate;
- wherein the plurality of passages comprise inlet passages having an open inlet end and a closed outlet end, and outlet passages having a closed inlet end and an open outlet end;
- wherein a given inlet passage, an adjacent outlet passage, and the internal wall between said inlet and said outlet passage define an overall passage;
- (ii) applying a first coating to at least part of the internal walls of at least 25% of the overall passages such that the first coating extends from the inlet end to a first coating end whereby an inlet coating length is defined, wherein the inlet coating length is x % of the substrate axial length, with 25≤x≤100, said first coating comprising at least one oxidation catalyst or at least one H2S suppressing material;
- (iii) applying a second coating to at least part of the internal walls of at least 25% of the overall passages such that the second coating extends from the outlet end to a second coating end whereby an outlet coating length is defined, wherein the outlet coating length is y % of the substrate axial length, with 25≤y≤100, said second coating comprising at least one oxidation catalyst or at least one H2S suppressing material;
- wherein the outlet coating comprises the at least one oxidation catalyst, and the inlet coating comprises the at least one H2S suppressing material, and the at least one oxidation catalyst and the at least one H2S suppressing material are separated by the internal walls of the wall flow filter substrate, and the total coating length is x+y, and x+y is greater than or equal to 150, and
- wherein the H2S suppressing material comprises CuO in the tenorite phase.
4 more elements
Dependencies are inferred from the claim text.