Iridium catalysts for purifying exhaust gas
AssigneeN.E. Chemcat Corporation
InventorsTakashi Itoh, Yukio Kosaki
Life of this patent
Estimating the term…
Abstract
A catalyst comprising an iridium supported on at least one carrier selected from the group consisting of metal carbides and metal nitrides for eliminating nitrogen oxides in exhaust gas in the presence of oxygen in excess of the stoichiometric quantity of oxidizing components for reducing components. The catalyst is effective for eliminating NO.sub.x in exhaust gas from lean burn engines such as lean burn gasoline engines and diesel engines containing excess O.sub.2 corresponding to an A/F ratio of 17 or over.
Claims8
A catalyst for purifying exhaust gas, consisting essentially of an iridium with crystallite diameter of 2 to 100 nm supported on one carrier selected from the group consisting of metal carbides and metal nitrides, wherein the supported amount of said iridium is 0.005 to 10.0% by weight based on the total amount of the iridium and the carrier.
Dependencies are inferred from the claim text.