An oxidation catalyst for treating an exhaust gas from a diesel engine and an exhaust system comprising the oxidation catalyst are described. The oxidation catalyst comprises: a first washcoat region for oxidising carbon monoxide (CO) and hydrocarbons (HCs), wherein the first washcoat region comprises a first platinum group metal (PGM) and a first support material; a second washcoat region for oxidising nitric oxide (NO), wherein the second washcoat region comprises platinum (Pt), manganese (Mn) and a second support material; and a substrate having an inlet end and an outlet end; wherein the second washcoat region is arranged to contact the exhaust gas at the outlet end of the substrate and after contact of the exhaust gas with the first washcoat region.

An oxidation catalyst is described for treating an exhaust gas produced by a diesel engine. The oxidation catalyst comprises: a substrate; a capture material for capturing at least one sulfur containing impurity in the exhaust gas produced by the diesel engine; wherein the capture material comprises a metal for reacting with an oxide of sulfur in the exhaust gas and particles of a refractory oxide, wherein the particles of the refractory oxide have a mean specific surface area 50 m.sup.2/g; and a catalytic region disposed on the substrate; wherein the catalytic region comprises a catalytic material comprising a platinum group metal (PGM) selected from the group consisting of platinum (Pt), palladium (Pd) and a combination of platinum (Pt) and palladium (Pd).

An oxidation catalyst for treating an exhaust gas produced by a stoichiometric natural gas (NG) engine comprising a substrate and a catalytic material for oxidising hydrocarbon (HC), wherein the catalytic material for oxidising hydrocarbon (HC) comprises a molecular sieve and a platinum group metal (PGM) supported on the molecular sieve, wherein the molecular sieve has a framework comprising silicon, oxygen and optionally germanium.

Catalyst washcoats with improved porosity and methods for making the washcoats are provided. The process comprises incorporation of an oil-in-water macroemulsion into the catalyst slurry prior to washcoating the carrier substrate, and calcining the washcoated carrier substrate to remove the oil-in-water macroemulsion. Also provided are catalyst articles comprising the washcoat and methods for abatement of exhaust gas emissions.

The technology disclosed herein provides a particulate filter that can appropriately avoid PM from passing toward the outlet cell and can exhibit an excellent PM capturing performance. The particulate filter 1 disclosed herein includes: an outercoat layer 20 provided on an inlet surface 16a of a partition 16 of a base material 10. The outercoat layer 20 at least includes: a lower layer 22 provided on the inlet surface 16a of the partition 16; and an upper layer 24 provided to cover the lower layer 22. The mean particle diameter of granules contained in the upper layer 24 is higher than the mean particle diameter of granules contained in the lower layer. The mean particle diameter of the granules in the lower layer 22 is from 0.4 m to 2.0 m inclusive, and the mean particle diameter of the granules in the upper layer 24 is from 2.0 m to 7.0 m inclusive. With such a configuration, PM can be captured in an inlet cell 12, thereby suitably avoiding PM from passing toward an outlet cell 14 and exhibiting an excellent PM capturing performance.

An oxidation catalyst for treating an exhaust gas from a diesel engine and an exhaust system comprising the oxidation catalyst are described. The oxidation catalyst comprises: a first washcoat region for oxidizing carbon monoxide (CO) and hydrocarbons (HCs), wherein the first washcoat region comprises a first platinum group metal (PGM) and a first support material; a second washcoat region for oxidizing nitric oxide (NO), wherein the second washcoat region comprises platinum (Pt), manganese (Mn) and a second support material; and a substrate having an inlet end and an outlet end; wherein the second washcoat region is arranged to contact the exhaust gas at the outlet end of the substrate and after contact of the exhaust gas with the first washcoat region.

A NOx control system includes a lean NOx catalyst and an alcohol generator. The lean NOx catalyst includes a substrate and a hydrocarbon selective catalytic reduction (HC-SCR) catalyst disposed on the substrate. The HC-SCR catalyst catalyzes a reduction of NOx with an alcohol. The alcohol generator generates the alcohol.

An oxidation catalyst for treating an exhaust gas from a diesel engine, which oxidation catalyst comprises: a first washcoat region comprising a first platinum group metal (PGM), a first support material and a NO.sub.x storage component; a second washcoat region comprising platinum (Pt), manganese (Mn) and a second support material; and a substrate having an inlet end and an outlet end.

Method for removal of soot, ash and metals or metal compounds, together with removal of NOx and SOx being present in process off-gasses or engine exhaust gasses.

Method and system for removal of soot, ash and heavy metals, and optionally additionally NOx and SOx being present in exhaust gas from an engine operated on heavy fuel oil.