One aspect of the invention relates an exhaust treatment system having an
SCR reactor following a NOx adsorber. Syn gas is used to regenerate the
NOx adsorber. Another aspect relates to an LNT/SCR provided with an
ammonia source separate from the LNT. A further aspect relates to a
system comprising first and second LNTs and one or more SCRs downstream
of the LNTs. A still further aspect relates to a device comprising first
and second NOx adsorbers contained in a single housing. Another aspect
relates to coating a surface of a moving part in an exhaust system with
an oxidation catalyst to mitigate fouling. Additional aspects of the
invention relate to strategies for controlling one or more of the time to
initiate a regeneration cycle, the time to terminate a regeneration
cycle, and the reductant injection rate during regeneration of LNT/SCR
exhaust treatment systems.