An exhaust gas purification catalyst device comprising a base material and a catalyst coating layer provided on the base material, wherein the catalyst coating layer contains zeolite particles, inorganic oxide particles other than the zeolite particles, and a catalyst precious metal, and the ratio d.sub.ZEO/d.sub.OX between the average particle diameter d.sub.ZEO of the zeolite particles and the average particle diameter d.sub.OX of the inorganic oxide particles other than the zeolite particles is 3.4 or less.

An apparatus for a gas turbine power plant that uniquely configures emission control equipment such that the plant can extend the emissions compliant operational range, the apparatus including a plurality of oxidation (CO) catalysts arranged in series.

An exhaust aftertreatment unit for cleaning exhaust gases. The exhaust aftertreatment unit includes an emission reducing module being a diesel particulate filter, DPF, and/or a diesel oxidation catalyst, DOC, a selective catalyst reduction, SCR, catalyst, an electrical heating element arranged upstream of the SCR catalyst, a casing housing at least the emission reducing module, and a service lid removably arranged to cover a service opening of the casing through which the emission reducing module may be accessed. The electrical heating element is removably arranged relative the casing and is arranged accessible upon removal of the service lid.

An exhaust system that includes a catalytic converter, selective catalytic reduction system, a muffler and, for certain applications, a diesel particulate filter that each include at least one filter that has an electric heating element, a metallic coating and a plurality of metal rods extending therethrough. The combination of elements are configured to heat the internal housings of the exhaust system and disrupt the direction of flow of exhaust gases which contain harmful toxic gases and pollutants and aid in removing and/or reducing said toxic gases and pollutants.

The present disclosure provides catalyst compositions capable of reducing nitrogen oxide (NO.sub.x) emissions in engine exhaust. The catalyst compositions include metal ion-exchanged zeolites having a domain size of less than about 1500 Ångstroms (Å), a crystallographic strain of less than about 0.7%, or both. Further provided are catalyst articles coated with such compositions, processes for preparing such catalyst compositions and articles, an exhaust gas treatment system including such catalytic articles, and methods for reducing NO.sub.x in an exhaust gas stream using such catalytic articles and systems.

A layered diesel oxidation catalyst for treatment of exhaust gas emissions from a diesel engine comprising: a flow-through monolith substrate having a honeycomb structure and comprising a front zone and a rear zone, wherein the front zone of the substrate comprises a combination of layers, one on top of another and comprising two or more of layers A, B and C; and the rear zone comprises Layer D, wherein: Layer A comprises platinum, palladium, or combinations thereof on a molecular sieve; Layer B comprises 1) platinum, palladium, or combinations thereof on a refractory metal oxide support; and 2) an alkaline earth metal, preferably barium, strontium or combinations thereof; Layer C comprises 1) a platinum group metal, which is platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) a promoter metal, which is manganese and/or bismuth; and layer D comprises 1) platinum or a combination of both platinum and palladium on a refractory metal oxide support; and 2) manganese (Mn).

An exhaust aftertreatment system for an internal combustion engine includes an outer casing defining an exhaust flow path for exhaust gases from the internal combustion engine, a selective catalytic reduction unit provided in the exhaust flow path for reducing nitrogen oxides, a urea dosing device for adding urea to the exhaust flow upstream of the selective catalytic reduction unit, and a rotatable mixer device for mixing the urea with exhaust gases upstream of the selective catalytic reduction unit. The exhaust aftertreatment system further comprises an air inlet valve provided upstream of the mixer device for introducing air into the exhaust flow path, and an electric motor arranged for rotating the mixer device to create a suction of air into the exhaust flow path via the air inlet valve.

A vehicle system includes a diesel oxidation catalyst. The vehicle system includes a hydrocarbon-selective catalytic reduction unit located downstream of the diesel oxidation catalyst. The hydrocarbon-selective catalytic reduction unit is configured to receive exhaust gas from the diesel oxidation catalyst. The vehicle system includes a turbocharger located downstream of the hydrocarbon-selective catalytic reduction unit. The turbocharger is configured to receive exhaust gas from the hydrocarbon-selective catalytic reduction unit.

An exhaust gas purification system for a gasoline engine is described the system comprising in consecutive order the following devices: •a first three-way-catalyst (TWC1), a gasoline particulate filter (GPF) and a second three-way-catalyst (TWC2), •wherein the oxygen storage capacity (OSC) of the GPF is greater than the OSC of the TWC1, wherein the OSC is determined in mg/l of the volume of the device.

A three-way catalyst article with improved ammonia emission control, and its use in an exhaust system for gasoline engines, is disclosed. The catalyst article for treating exhaust gas from a gasoline engine comprising: a substrate comprising an inlet end, an outlet end with an axial length L; a first catalytic region beginning at the inlet end, wherein the first catalytic region comprises a first zeolite; and a second catalytic region beginning at the outlet end, wherein the second catalytic region comprises a second platinum group metal (PGM) component, a second oxygen storage capacity (OSC) material, and a second inorganic oxide; wherein the second PGM component is selected from the group consisting of palladium, platinum, rhodium and a combination thereof.