Patent ID: 7375054

Claim:
An exhaust gas treatment catalyst characterized by containing a compound oxide expressed by the following general formula (1): AMxOy (1) (wherein A represents an alkali metal or alkaline earth metal, M represents Cr, Mn, Fe, Co or Ni, O represents oxygen, and 0<x≦4 and 0<y≦8); and further containing a perovskite compound oxide expressed by the following general formula (2) in addition to said compound oxide of general formula (1): Ln 1-α A α MO3 (2) (wherein Ln represents a lanthanide group element, A represents an alkali metal, M represents Cr, Mn, Fe, Co or Ni, O represents oxygen, and 0<α≦0.5), wherein a noble metal is contained in some of said compound oxide of general formula (1).