Abstract: A catalyst for purifying exhaust gases includes a support including at le one composite selected from the group consisting of TiO.sub.2 --Al.sub.2 O.sub.3, ZrO.sub.2 --Al.sub.2 O.sub.3 and SiO.sub.2 --Al.sub.2 O.sub.3 composites, an NO.sub.x adsorbent including at least one member selected from the group consisting of alkali metals, alkaline-earth metals and rare-earth elements and loaded on the support, and a noble metal catalyst ingredient loaded on the support. The composites constituting the support improve initial NO.sub.x conversion of the catalyst, but also inhibit NO.sub.x purifying performance thereof from degrading even after a durability test.

Abstract: A catalyst for purification of exhaust gases comprising: a support substrate; an active alumina coating layer comprising at least one of nickel oxide and cobalt oxide formed on the surface of the support substrate; a composite oxide comprising cerium oxide and zirconium oxide formed in the active alumina coating layer; and noble metal catalyst ingredients comprising at least one of platinum, palladium and rhodium loaded on the active alumina coating layer. The catalyst offers a decreased hydrogen sulfide H.sub.2 S emission and conversion ratios for hydrocarbon (HC), carbon monoxide (CO), and nitrogen oxides (NOx) equivalent to or superior to those of conventional catalysts.