| abstract |
An oxidation catalyst for treating an exhaust gas produced by a diesel engine comprises a catalytic region 2 and a substrate 1. The catalytic region comprises antimony (Sb) or an oxide thereof; platinum (Pt) and/or palladium (Pd); and a refractory oxide (e.g. alumina, silica, alumina-silica composite oxide) support material. The platinum/palladium is supported on the support material. The antimony or oxide thereof is either supported on the support material, or the refractory oxide comprises the antimony or oxide thereof. The refractory oxide may be a particulate refractory oxide. The catalytic region may comprise a hydrocarbon adsorbant material, such as a zeolite. Second 3 and third 4 catalytic regions may provide a passive NOx adsorber (PNA), lean NOx trap (LNT) or diesel oxidation catalyst (DOC). The catalytic regions may be provided as zones and/or layers on the substrate. The oxidation catalyst is uses in an exhaust system in a vehicle. A method for treating exhaust gas from a diesel engine uses the oxidation catalyst. |