Patent ID: 9032709
Filing Date: 2015-05-19
Classification: B01D,B01J,F01N,Y02T,Y10S,Y10T

Abstract:
1. A method for treating emissions produced in an exhaust stream from a diesel engine comprising NOx and particulate matter, the method comprising: (a) passing the exhaust stream through an oxidation catalyst wherein a substantial portion of NO is oxidized to NO (b) metering at periodic intervals, ammonia or an ammonia precursor into the NO (c) subsequently passing the exhaust stream containing ammonia through a wall flow monolith wherein particulate matter is filtered and a substantial portion of NOx is reduced to N wherein the wall flow monolith has a plurality of longitudinally extending passages formed by longitudinally extending walls bounding and defining said passages, wherein the 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, the wall flow monolith having a porosity of from 50% to 60% and an average pore size of from 10 to 25 microns wherein the wall flow monolith comprises a washcoat of SCR catalyst composition that permeates the walls, the SCR catalyst composition comprising a zeolite and base metal component selected from one or more of a copper and iron component, the washcoat permeating the walls at a loading up to 2.4 g/in