Catalytic wall-flow filter

Abstract

A wall-flow filter for an exhaust system of a combustion engine comprises: a plurality of channels in honeycomb arrangement, wherein at least some of the channels are plugged at an upstream end and at least some of the channels not plugged at the upstream end are plugged at a downstream end; an oxidation catalyst on a substantially gas impermeable zone at an upstream end of the channels plugged at the downstream end; and a gas permeable filter zone downstream of the oxidation catalyst for trapping soot, in that in an exhaust system, preferably a diesel exhaust system, the oxidation catalyst, which preferably includes a platinum group metal, is capable of generating sufficient NO2 from NO to combust the trapped soot continuously at a temperature less than 400° C.

Dependencies are inferred from the claim text.