Method for purifying exhaust gases

摘要

An automotive exhaust catalyst includes a support, which is less likely to adsorb SOx contained in exhaust gases thereon, an NOx storage compound loaded on the support, and a noble metal element loaded on the support. The support is an alumina support with a Ti-Zr composite oxide loaded thereon, or is formed of a Ti-Zr or Ti-Zr-Y composite oxide. The composite oxide inhibits the NOx storage compound, which is selected from alkali metals, alkaline-earth metals and rare-earth elements, from being poisoned by sulfur, and enhances the thermal resistance of the support. Thus, the automotive exhaust catalyst can effectively purify NOx contained in lean-side exhaust gases, even after it is subjected to a thermal durability test.