Exhaust gas purifying catalyst
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsShinichi Takeshima, Akio Koyama
Life of this patent
Estimating the term…
Abstract
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.
Claims9
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.
An exhaust gas purifying catalyst, comprising:
- a porous silica support, wherein the porous silica support comprises silica primary particles having a pore structure;
- and
- a plurality of perovskite-type composite metal oxide particles supported in the pore structure of said porous silica support,
- wherein, in the pore distribution of said porous silica support, a first peak attributable to a space between the silica primary particles is in the range of 5 to 50 nm, and a second peak attributable to the pore structure of the silica primary particle is in the range of 1 to 5 nm,
- 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.
Dependencies are inferred from the claim text.