Patent ID: 7251929

Claim:
An exhaust aftertreatment system, comprising: a NOx adsorber-catalyst configured to treat an exhaust flow; an SCR catalyst configured to adsorb ammonia released by the NOx adsorber-catalyst during denitration and to subsequently use the ammonia to reduce NOx in the exhaust; a particulate filter located upstream of the NOx adsorber-catalyst or downstream of the SCR catalyst; and means for preventing the SCR catalyst from becoming heated to near the same peak temperatures as the NOx adsorber-catalyst during desulfation of the NOx adsorber-catalyst, the means being disposed between the NOx adsorber-catalyst and the SCR catalyst; wherein the means comprises a flow diverter configured to prevent the exhaust leaving the NOx adsorber-catalyst from entering the SCR catalyst during desulfation of the NOx adsorber-catalyst.