Abstract: An NOx storage member including at least one member selected from the group consisting of alkali metals, alkaline-earth metals and rare-earth elements, and at least one noble metal selected from the group consisting of Pt, Pd and Rh are loaded on a support including a porous oxide including TiO2 at least and ZrO2 on which Rh is loaded in advance. H2, which is generated by Rh/ZrO2, inhibits the sulfur poisoning, and the support, which includes TiO2 at least, secures the initial NOx purifying capability, thereby further inhibiting the sulfur poisoning. Accordingly, it is possible to inhibit the NOx storage member from the sulfur poisoning, and to maintain a high NOx conversion even after a durability test.

Abstract: A catalyst for purifying an exhaust gas includes a support including rutile titania, an NOx storage material including at least on element selected from alkali metals, alkaline-earth metals and rare-earth elements and loaded on the support, and a noble metal loaded on the support. Since the rutile TiO2 and the NOx storage material form a fine composite oxide, the NOx storage material is likely to decompose even when it is subject to the sulfur poisoning, and the NOx storage material easily recovers the NOx storage ability. Therefore, the NOx storage material can be inhibited from the sulfur poisoning, and a high NOx conversion ratio can be maintained even after the service at an elevated temperature.