CATALYST FOR EXHAUST GAS CLEANING

摘要

A catalyst for exhaust gas cleaning which has cleaning ability even at high temperatures. This catalyst comprises a crystalline composite zirconium oxide and, deposited thereon, an alkali metal and a noble metal, wherein part of the zirconium of the composite zirconium oxide has been displaced by at least one element selected from the group consisting of alkaline earth metals, rare earth metals, and Group IIIB elements and the elongation of the crystal lattice due to this element displacement is an approximately theoretical value.