Patent ID: 7650746
Filing Date: 2010-01-26
Classification: B01D,F01N,Y02A,Y02T

Abstract:
1. An exhaust treatment system, comprising: a lean NOx trap adapted to adsorb and store NOx from lean exhaust and to reduce and release the stored NOx in a reducing atmosphere; a conduit configured to channel exhaust to the lean NOx trap whereby any exhaust reaching the lean NO a fuel reformer comprising an effective amount of a steam reforming catalyst positioned within the conduit, whereby at least a bulk of the exhaust passing through the conduit also passes through the fuel reformer; and an ammonia SCR catalyst configured to receive gases desorbed from the lean NOx trap and functional to catalyze a reaction with ammonia that can reduce NOx in a lean environment; wherein the lean NOx trap functions to generate ammonia during regeneration and the SCR catalyst functions to adsorb and store ammonia so generated; and the SCR catalyst functions, in a period immediately following regeneration of the lean NOx trap, to reduce NOx passing lean NOx trap by catalyzing reaction of NOx with stored ammonia.