To provide such a catalyst for purification of exhaust gas that the temp. region to reduce NOx in a lean atmosphere can be extended to a lower temp. side, a high NOx purification rate can be obtd. under normal operational conditions, and even when a gas is passed through a stoichiometric atmosphere at high temp. for a long time, NOx can be removed at a high efficiency in both of stoichiometric and lean atmosphere.
This catalyst consists of a catalyst 1 containing a catalyst prepared by depositing at least Pd and K on alumina and/or a catalyst comprising hexaaluminate containing Sr, La and Cu, and a catalyst 2 containing a catalyst essentially comprising alumina and containing multiple oxide containing In and/or Co, and/or a catalyst prepared by depositing Ag on alumina, or a catalyst essentially comprising alumina and containing multiple oxide containing In and/or Ga and Co. Or, this catalyst consists of another catalyst 1 containing a catalyst essentially comprising alumina and containing multiple oxide of In and Co, or a catalyst essentially comprising alumina and containing multiple oxide of In Ga and Co, and another catalyst 2 prepared by depositing at least one of Pd, Rh and Pt on alumina.
MATSUHISA TOSHIO
NAKANO TOSHIHIKO
ITO JUNJI
MUROFUSHI YASUYUKI
MUKAI TSUNESABURO
SEKIBA TORU
OKADA AKIHIDE
NISSAN MOTOR