Abstract: A molten-salt type catalyst is adapted for purifying particulate materials, which are contained in an exhaust gas emitted from an internal combustion engine and contain carbon. It includes a solid support and a catalytic ingredient. The catalytic ingredient is loaded on the solid support, and includes at least one member selected from the group consisting of silver nitrate, alkali metal nitrate, alkaline-earth metal nitrate and rare-earth nitrate. The molten-type catalyst can efficiently burn and remove the particulate materials even in a low temperature range.

Abstract: A molten-salt type catalyst is adapted for purifying particulate materials, which are contained in an exhaust gas emitted from an internal combustion engine and contain carbon. It includes a solid support and a catalytic ingredient. The catalytic ingredient is loaded on the solid support, and includes at least one member selected from the group consisting of silver nitrate, alkali metal nitrate, alkaline-earth metal nitrate and rare-earth nitrate. The molten-type catalyst can efficiently burn and remove the particulate materials even in a low temperature range.

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.

Abstract: An exhaust gas purifying catalyst for oxidizing HC and CO and for reducing NOx is provided, which comprises at least one oxide of rare earth element, rhodium, and at least one of platinum and palladium loaded on alumina grains. The major amount of rhodium is dispersed on the oxide of rare earth element. Thus, the rhodium solidification into the alumina grains is prevented. Further, when cerium oxide accompanying lanthanum oxide, neodymium oxide or a mixture thereof is used as the oxide of rare earth element, the sintering of cerium oxide or palladium at a high temperature is suppressed since it forms a complex oxide with lanthanum oxide, neodymium oxide or a mixture thereof. Additionally, when stabilized alumina grains in which a rare earth element and an alkali earth element are present in a solid solution state are used, the deterioration of NOx purifying activity of the catalyst at a high temperature is suppressed.