초록 ▼

A catalyst for purifying exhaust gases, which is composed of a catalyst substrate, a first porous support layer supporting barium as a NOx-occluding material and palladium, which is formed on the catalyst support, and a second porous support layer supporting platinum, which is formed on the first po

A catalyst for purifying exhaust gases, which is composed of a catalyst substrate, a first porous support layer supporting barium as a NOx-occluding material and palladium, which is formed on the catalyst support, and a second porous support layer supporting platinum, which is formed on the first porous support layer. Platinum efficiently oxidizes nitrogen monoxide to be converted into nitrogen dioxide. Palladium is supported in a highly dispersed state even after endurance to act as inlet and outlet of barium for nitrogen dioxide or the like, whereby absorption and emission of nitrogen oxides can be performed smoothly, and accordingly, the purification performance for nitrogen oxides is improved.

대표청구항 ▼

A process for purifying carbon monoxide, hydrocarbons and nitrogen oxides in exhaust gases in oxygen-rich atmosphere, thereby purifying the exhaust gases, the process comprising: bringing exhaust gases in oxygen-rich atmosphere, whose oxygen concentration is more than required for oxidizing the comp

A process for purifying carbon monoxide, hydrocarbons and nitrogen oxides in exhaust gases in oxygen-rich atmosphere, thereby purifying the exhaust gases, the process comprising: bringing exhaust gases in oxygen-rich atmosphere, whose oxygen concentration is more than required for oxidizing the components to be oxidized therein, into contact with a catalyst: the catalyst comprising: a catalyst substrate; a first porous support layer consisting essentially of first porous support supporting palladium and at least one kind of NOx-occluding material selected from the group consisting of alkali metals, alkaline earth metals and rare earth elements, and formed on a surface of said catalyst substrate; and a second porous support layer comprising a second porous support supporting at least platinum, and formed on a surface of said first porous support layer, and wherein said second porous support layer supports no components having oxygen-occluding ability.