| 摘要 |
PURPOSE:To obtain catalyst consisting of rhodium and platinum as the main active ingredients which is capable of keeping high purifying capability for the three component HC, CO, and NOx without narrowing window width even under the actual running mode condition of periodical A/F variation width. CONSTITUTION:The catalyst consists primarily of a monolithic support on which active alumina coat is formed and catalyst components, e.g., cerium, phosphorus, platinum, and rhodium, together with lanthanum, iron, or nickel as needed, in the form of oxide or element partially which are supported on the active alumina coat. Preferably, the active alumina coat contains 0.5 to 30 g of cerium per 1 liter of complete catalyst, 0 to 10 g of lanthanum, 0 to 10 g of iron, 0 to 20 g of nickel, 0.2 to 3.0g of platinum, 0.2 to 3.0 g of rhodium, and 0.003 to 0.95 g of phosphorus in the form of oxide or element. |
