CATALYST FOR PURIFYING EXHAUST GAS, METHOD OF REGENERATING THE SAME, EXHAUST GAS PURIFICATION APPARATUS USING THE SAME AND METHOD OF PURIFYING EXHAUST GAS

摘要

A catalyst for purification of exhaust gas in which a noble metal is supported on a metal-oxide support wherein, in a oxidation atmosphere, the noble metal exists on the surface of the support in high oxidation state, and the noble metal binds with a cation of the support via an oxygen atom on the surface of the support to form a surface oxide layer and, in a reduction atmosphere, the noble metal exists on the surface of the support in a metal state, and an amount of noble metal exposed at the surface of the support, measured by CO chemisorption, is 10% or more in atomic ratio to a whole amount of the noble metal supported on the support.