초록 ▼

Described is a catalyzed soot filter wherein the inlet coating of the filter comprises an oxidation catalyst comprising platinum (Pt) and optionally palladium (Pd), wherein the outlet coating of the filter comprises an oxidation catalyst comprising Pd and optionally Pt, wherein the Pt concentration

Described is a catalyzed soot filter wherein the inlet coating of the filter comprises an oxidation catalyst comprising platinum (Pt) and optionally palladium (Pd), wherein the outlet coating of the filter comprises an oxidation catalyst comprising Pd and optionally Pt, wherein the Pt concentration in the outlet coating is lower than the Pt concentration in the inlet coating and wherein the weight ratio of Pt:Pd in the outlet coating is in the range of from 0:1 to 2:1; and wherein the inlet coating and the outlet coating are present on the wall flow substrate at a coating loading ratio in the range of from 0.5 to 1.5, calculated as ratio of the loading of the inlet coating (in g/inch3 (g/(2.54 cm)3)):loading of the outlet coating (in g/inch3 (g/(2.54 cm)3)). Systems include such catalyzed soot filters, methods of diesel engine exhaust gas treatment and methods of manufacturing catalyzed soot filters are also described.

대표청구항 ▼

1. 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

1. 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 that 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, with 0