Exhaust gas purifying catalyst, method for recovering exhaust gas purifying catalyst, and catalyst system for exhaust gas purification

An exhaust gas purifying catalyst, which inhibits coagulation of noble metal particles during gas purification, comprising:

• a combined oxide (A) containing a first oxide (A-1) containing an alkaline earth metal and/or a rare earth metal and an inorganic second oxide (A-2);
• and
• a noble metal (B) supported by the combined oxide (A),
• wherein a weight ratio of the noble metal (B) to the first oxide (A-1) containing the alkaline earth metal and/or the rare earth metal is from 1:90 to 1:200 so that the exhaust gas purifying catalyst inhibits coagulation of the noble metal particles during the gas purification.

An exhaust gas purifying catalyst, which inhibits coagulation of noble metal particles during gas purification, comprising:

• a combined oxide (A) containing neodymium oxide (A-1) and an inorganic second oxide (A-2), the inorganic second oxide (A-2) comprising at least one oxide selected from the group consisting of Al2O3, SiO2, ZrO2, TiO2 and zeolite;
• and
• a noble metal (B) supported by the combined oxide (A), the noble metal (B) being at least one element selected from the group consisting of Pt, Pd and Rh;
• and
• a weight ratio of the noble metal (B) to the neodymium oxide (A-1) is from 1:90 to 1:200 such that the exhaust gas purifying catalyst inhibits coagulation of the noble metal particles during the gas purification.