A hydrocarbon and NOx catalyst trap includes a three-way catalyst, and a zeolite layer adjacent to the three-way catalyst and including alumina and silica arranged to form a repeating skeletal frame that defines cavities including active metal active sites for hydrocarbon and NOx trapping such that individual atoms of the active metal are bound to the frame within the cavities via oxygen atoms.

To provide a hydrocarbon adsorbent having high hydrocarbon adsorbing properties even after exposed to a high temperature/high humidity reducing atmosphere.

A hydrocarbon adsorbent, which includes a FAU type zeolite having a lattice constant of at least 24.29 and containing copper. Such a hydrocarbon adsorbent may be used for a method for adsorbing hydrocarbons to be exposed to a high temperature/high humidity environment, and may be used particularly for a method for adsorbing hydrocarbons in an exhaust gas of an internal combustion engine, such as an automobile exhaust gas.

The present invention relates to a catalyst comprising a carrier substrate of the length L extending between substrate ends a and b and a first washcoat zone, which comprises a) a zeolite, b) a redox active base metal compound and c) palladium in oxidic or metallic state which is fixed to the surface of a support oxide.

An exhaust system for a diesel engine comprises an oxidation catalyst for treating an exhaust gas from the diesel engine and an emissions control device, wherein the oxidation catalyst comprises: a first washcoat zone for oxidizing carbon monoxide (CO) and hydrocarbons (HCs), wherein the first washcoat zone comprises a first platinum group metal (PGM), which is a combination of platinum and palladium, a first support material and a hydrocarbon adsorbent material, which is a zeolite, and wherein the first washcoat zone does not comprise rhodium and is substantially free of manganese or an oxide thereof; a second washcoat zone for oxidizing nitric oxide (NO), wherein the second washcoat zone comprises platinum (Pt) and manganese (Mn) disposed or supported on a second support material, wherein the second support material comprises a refractory metal oxide, wherein the refractory metal oxide is silica-alumina or an alumina doped with silica in a total amount of 0.5 to 45% by weight of the alumina, and wherein the second washcoat zone does not comprise a hydrocarbon adsorbent material, which is a zeolite; and a substrate having and inlet end and an outlet end, and wherein the second washcoat zone is disposed at an outlet end of the substrate, and the first washcoat zone disposed at an inlet end of the substrate; and wherein the emissions control device is a selective catalytic reduction (SCR) catalyst, a selective catalytic reduction filter catalyst, a diesel particulate filter (DPF), or a catalyzed soot filter (CSF).

Methods and systems are featured for reducing harmful exhaust gas components of combustion devices such as gasoline-powered combustion engines (e.g., predominately stoichiometric running engines). The methods and systems include an underbody combination of a hydrocarbon trap (HCT), suited for cold start hydrocarbon adsorption, as well as an associated NOx trap. The system is inclusive of a control unit for extending a lean exhaust condition reaching the desorbing HCT as to avoid a deficiency in oxygen during the time period of HCT desorption. The system is also inclusive of one or more TWCs as in one associated with the underbody HCT-NOx-trap combination and/or one positioned in a close coupled position. Platinum group metals as in Pd, Rh and Pt are also featured on one, two or all three of the HCT, NOx-trap, and TWC when present.

The invention provides an exhaust gas cleaning oxidation catalyst and in particular to an oxidation catalyst for cleaning the exhaust gas discharged from internal combustion engines of compression ignition type (particularly diesel engines). The invention further relates to a catalysed substrate monolith comprising an oxidising catalyst on a substrate monolith for use in treating exhaust gas emitted from a lean-burn internal combustion engine. In particular, the invention relates to a catalysed substrate monolith comprising a first washcoat coating and a second washcoat coating, wherein the second washcoat coating is disposed in a layer above the first washcoat coating.

An exhaust gas purifying composition of the present invention contains zeolite that is BEA zeolite having an SiO.sub.2/Al.sub.2O.sub.3 molar ratio of greater than 25 and 600 or less and containing phosphorus. Furthermore, the exhaust gas purifying composition preferably contains zirconium in addition to phosphorus. Furthermore, the zeolite has an SiO.sub.2/Al.sub.2O.sub.3 molar ratio of from 30 to 150. The present invention provides an exhaust gas purifying composition having excellent HC adsorbability for exhaust gas purification in internal combustion engines such as gasoline engines.

An internal combustion engine includes an engine body, an HC adsorption and removal catalyst in an exhaust, including an HC adsorption layer and a catalyst layer, and having a desorption temperature of the HC from the HC adsorption layer lower than an HC removal temperature of a temperature where a rate of removal of HC at the catalyst layer is a predetermined rate or more when an air-fuel ratio of the exhaust is near the stoichiometric air-fuel ratio, and an air feed device for feeding air to the HC adsorption and removal catalyst. A control device for an internal combustion engine includes an air feed control for controlling feed air to the HC adsorption and removal catalyst when a condition stands. The condition includes the temperature of the HC adsorption and removal catalyst being the desorption temperature or more and less than the HC removal temperature.

Exhaust gas systems include an oxidation catalyst (OC) capable of receiving exhaust gas and oxidizing one or more of combustible hydrocarbons (HC) and one or more nitrogen oxide (NOx) species, a selective catalytic reduction device (SCR) disposed downstream from and in fluid communication with the OC via a conduit, and an electrically heated catalyst (EHC) disposed at least partially within the conduit downstream from the OC and upstream from the SCR. The EHC comprises a heating element having an outer surface including one or more second oxidation catalyst materials capable of oxidizing CO, HC, and one or more NOx species. The OC includes one or more storage materials individually or collectively capable of storing NOx and/or HC species. Exhaust gas can be supplied by an internal combustion engine which can optionally power a vehicle.

An exhaust system for a compression ignition engine comprising an oxidation catalyst for treating carbon monoxide (CO) and hydrocarbons (HCs) in exhaust gas from the compression ignition engine, wherein the oxidation catalyst comprises: a platinum group metal (PGM) component selected from the group consisting of a platinum (Pt) component, a palladium (Pd) component and a combination thereof; an alkaline earth metal component; a support material comprising a modified alumina incorporating a heteroatom component; and a substrate, wherein the platinum group metal (PGM) component, the alkaline earth metal component and the support material are disposed on the substrate.