| 摘要 |
<P>PROBLEM TO BE SOLVED: To easily recover the activity of a catalyst, in which at least Rh is deposited as an active species, even when the activity is deteriorated after its durability limit. <P>SOLUTION: The exhaust gas cleaning catalyst, in which at least Rh is deposited on a carrier containing at least Al<SB>2</SB>O<SB>3</SB>and its activity is deteriorated because of being used in a high-temperature oxygen-excessive atmosphere, is treated at a high-temperature stoichiometric amount of air or in a reducing atmosphere. The activity of the catalyst is deteriorated since the Rh deposited on the carrier is subjected to the solid-phase reaction with Al<SB>2</SB>O<SB>3</SB>in the high-temperature oxygen-excessive atmosphere. Therefore, the activity-deteriorated catalyst is exposed to the high-temperature stoichiometric point or the reducing atmosphere so that metal Rh is precipitated again and consequently the activity of this catalyst can be recovered. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
