Patent ID: 9517457
Filing Date: 2016-12-13
CPC Classification: B01D,B01J,F01N,Y02A,Y02C,Y02T

Claim Text:
1. A system, comprising: an internal combustion engine having an exhaust aftertreatment system for receiving an exhaust gas produced from operation of the internal combustion engine; a reductant system including a reductant source; and a diesel exhaust aftertreatment system that includes at least one selective catalytic reduction (SCR) catalyst positioned downstream of a connection of the reductant source to the exhaust aftertreatment system, wherein the at least one SCR catalyst includes at least three formulations on portions of the SCR catalyst, the at least three formulations including a first formulation, a second formulation, and a third formulation, wherein the first formulation produces less N the first formulation is a vanadium based catalyst formulation, the second formulation is a copper-zeolite catalyst formulation, and the third formulation is an iron-zeolite catalyst formulation, and a first portion of the SCR catalyst with the first formulation is located upstream of a second portion of the SCR catalyst with the second formulation.