Abstract: An exhaust system for an internal combustion engine, the exhaust system comprising, a lean NOx trap, and a wall flow monolithic substrate having a pre-coated porosity of 40% or greater, and comprising an oxidation catalytic zone, the oxidation catalytic zone comprising a platinum group metal loaded on a first support, the first support comprising at least one inorganic oxide and a zinc compound.

Abstract: An exhaust system for an internal combustion engine has a catalysed ceramic wall flow particulate filter coated with a washcoat composition. The washcoat composition includes an oxidation catalyst of at least one platinum group metal and a NOx absorbent. The washcoat composition has a D50 of less than or equal to 8 ?m. The NOx absorbent absorbs NOx contained in an exhaust gas when the composition of the exhaust gas is lambda >1, and releases the NOx absorbed in the NOx absorbent when the exhaust gas composition is 1?lambda. The exhaust system has a platinum group metal catalyst upstream of the filter for oxidising NO to NO2 at least when the composition of the exhaust gas is lambda >1. The uncoated portions of the ceramic wall flow particulate filter have a porosity of >40% and a mean pore size of 8-25 ?m.

Abstract: An exhaust system for an internal combustion engine comprises a catalysed particulate filter comprising a NOx absorbent capable of absorbing NOx contained in an exhaust gas when the composition of the exhaust gas is lambda >1, and capable of releasing the NOx absorbed in the NOx component when the exhaust gas composition is 1?lambda, characterised in that the exhaust system further comprises a catalyst capable of oxidising NO to NO2 at least when the air-fuel ration of the exhaust gas is lean.