Patent ID: 8084389

Claim:
A sulfur storage catalyst comprising: a support substrate; a coating layer comprising a porous oxide, and being formed on a surface of the support substrate; a noble metal being supported on the coating layer; and an SO x storage material being selected from the group consisting of alkali metals and alkaline-earth metals, and being supported on the coating layer; the sulfur storage catalyst being put in place on an exhaust-gas upstream side of NO x storage-and-reduction type catalyst to be used, and storing sulfur component in exhaust gas as sulfur oxide; wherein the sulfur storage catalyst has: an upstream-side catalytic portion in which at least the noble metal is supported and no SO x storage material being selected from the group consisting of Mg, K, Na, Sr and Ca is supported on an exhaust-gas upstream side of the coating layer; and a downstream-side catalytic portion in which an SO x storage material being selected from the group consisting of Mg, K, Na, Sr and Ca is supported on the coating layer on an exhaust-gas downstream side of the upstream-side catalytic portion.