Exhaust gas purifying catalyst

摘要

According to the present invention, an exhaust gas purifying catalyst is provided. The catalyst comprises a porous silica support comprising silica having a pore structure, and a perovskite-type composite metal oxide particle supported in the pore structure of the porous silica support. Further, the peak attributable to the space between silica primary particles is in the range of 3 to 100 nm in the pore distribution of the porous silica support.

主权项

1. An exhaust gas purifying catalyst, wherein the catalyst comprises a porous silica support comprising silica having a pore structure, and a perovskite-type composite metal oxide particle supported in the pore structure of said porous silica support;
wherein a peak attributable to a space between silica primary particles is in the range of 5 to 50 nm and a peak attributable to the pore structure of silica is in the range of 1 to 5 nm in the pore distribution of said porous silica support; wherein said perovskite-type composite metal oxide is a perovskite-type composite metal oxide having the following formula:
ABO3-x wherein A is selected from the group consisting of lanthanum La, strontium Sr, cerium Ce, barium Ba, calcium Ca and a combination thereof; B is selected from the group consisting of cobalt Co, iron Fe, nickel Ni, chromium Cr, manganese Mn, Magnesium Mg and a combination thereof; O is oxygen; and −0.2≦x≦0.2; and wherein said perovskite-type composite metal oxide is supported in an amount of 1 to 10 mass %/g-porous silica support in terms of the metal B constituting the perovskite-type composite metal oxide.