Catalyst support and catalyst for exhaust-gas purification

Abstract

The invention provides a catalyst support which produces the excellent effect of inhibiting noble-metal catalyst particles from sintering and a catalyst for exhaust-gas purification. The catalyst support, which is for noble-metal supporting, comprises a composite oxide of: an electron-accepting element (La) which has the property of accepting an electron from a noble metal element (Pt) upon approach of or contact with the noble metal element and which does not change in valence through oxidation / reduction reactions; and other element(s) (Si). The invention also provides an exhaust-gas purification catalyst on this catalyst support for carrying noble-metal catalyst particles.

Description

Catalyst carrier and catalyst for exhaust gas purification technical field The present invention relates to a catalyst carrier for supporting noble metal catalyst particles, and an exhaust gas purification catalyst in which noble metal catalyst particles are supported on the catalyst carrier. Background technique In the case of a catalyst in which noble metal particles are supported on a carrier as a catalyst component, the noble metal particles are supported on the carrier in the form of fine particles in order to improve the activity. This is to maximize the specific surface area of ​​the catalyst component. However, if the particle size of the catalyst component is reduced, the surface energy thereof increases, so that mutual sintering (sintering) becomes easy. Especially in exhaust gas purification catalysts, the catalyst is exposed to high temperatures of hundreds of degrees due to the heat of the exhaust gas or heat generated by the reaction, which tends to cause no...

AI Technical Summary

Problems solved by technology

However, if the particle diameter of the catalyst component is reduced, its surface energy increases, so it becomes easy to sinter with each other (sintering)

Especially in exhaust gas purification catalysts, the catalyst is exposed to high temperatures of hundreds of degrees due to the heat of the exhaust gas or the heat generated by the reaction, which tends to lead to sintering of noble metal particles, increase in particle size, and decrease in activity

Images