摘要:
A catalysed substrate monolith 12 for use in treating exhaust gas emitted from a lean-burn internal combustion engine, which catalysed substrate monolith 12 comprising a first washcoat coating 16 and a second washcoat coating 18, wherein the first washcoat coating comprises a catalyst composition comprising at least one platinum group metal (PGM) and at least one support material for the at least one PGM, wherein at least one PGM in the first washcoat coating is liable to volatilise when the first washcoat coating is exposed to relatively extreme conditions including relatively high temperatures, wherein the second washcoat coating comprises at least one metal oxide for trapping volatilised PGM and wherein the second washcoat coating is oriented to contact exhaust gas that has contacted the first washcoat coating.
摘要:
An exhaust system for internal combustion engines, and a catalyzed substrate for use in an exhaust system, is disclosed. The exhaust system comprises a lean NOx trap and the catalyzed substrate. The catalyzed substrate has a first zone and a second zone, wherein the first zone comprises a platinum group metal loaded on a support and the second zone comprises copper or iron loaded on a zeolite. The first zone or second zone additionally comprises a base metal oxide or a base metal loaded on an inorganic oxide. Also provided are methods for treating an exhaust gas from an internal combustion engine using the exhaust system. The exhaust system is capable of storing NH3 generated in rich purging, reacting the NH3 with slip NOx from the NOx trap, controlling H2S released from NOx trap desulfation, and oxidizing slip hydrocarbons and carbon monoxide. When the catalyzed substrate is a filter substrate, it is also capable of removing soot from exhaust system.
摘要:
A NOx absorber catalyst comprising an extruded solid body comprises either: (A) 10-95% by weight of at least one binder/matrix component; and 5-90% by weight of a zeolitic molecular sieve, a non-zeolitic molecular sieve or a mixture of any two or more thereof, which catalyst comprising at least one metal comprising (a) at least one precious metal; and (b) at least one alkali metal or at least one alkaline earth metal, wherein (a) and (b) are carried in one or more coating layer(s) on a surface of the extruded solid body; or (B) 10-95% by weight of at least one binder/matrix component; and 5-80% by weight optionally stabilized ceria, which catalyst comprising at least one metal comprising (a) at least one precious metal; and (b) at least one alkali metal or at least one alkaline earth metal.
摘要:
A traction member for use with driving pulleys, consisting of one or more load-bearing elements and a plastics part which is arranged between the load-bearing elements and a force-transmission surface of the traction member. The overall friction value results from the fact that the force-transmission surface, which comes into contact with the driving pulley, has at least two regions, and that these regions are formed from different materials A and B having different coefficients of friction. The regions are in the form of strips in the longitudinal direction of the traction member. The carrier material A is softer and has a higher coefficient of friction and the further materials B1, B2, B3 etc. are each harder and each have a lower coefficient of friction. Preferably, the materials A, B1, B2, B3 etc. are applied in one work step by extrusion.
摘要:
An apparatus comprising a compression ignition engine and an exhaust system therefor comprising at least one exhaust system component for treating exhaust gas and means for generating an exotherm for heating the at least one exhaust system component, which exotherm generating means consisting essentially of a catalyst and means for injecting hydrocarbon into exhaust gas for combustion on the catalyst, which catalyst consisting essentially of both a palladium (Pd) component and a platinum (Pt) component, and an optional support material, disposed on a substrate monolith.
摘要:
A rheometeris disclosed for determining flow characteristics of a fluid. The rheometer comprises a circuit in which the fluid is arranged to flow. The circuit comprises a duct and a plurality of flow elements, each comprising a flow environment arranged in fluid communication with the duct. The flow environment of each element is arranged to convey fluid from an up-stream position to a downstream position of the respective flow element. The rheometer further comprises pressure sensing means arranged to determine fluid pressure at the upstream position and the downstream position of each of the plurality of flow elements. At least two of the plurality of flow elements comprise different flow environments for the fluid such that the rheometer can determine the flow characteristics of the fluid at a particular instant in time.
摘要:
A method of coating a honeycomb monolith substrate comprising a plurality of channels with a liquid comprising a catalyst component comprises the steps of: (i) holding a honeycomb monolith substrate substantially vertically; (ii) introducing a pre-determined volume of the liquid into the substrate via open ends of the channels at a lower end of the substrate; (iii) sealingly retaining the introduced liquid within the substrate; (iv) inverting the substrate containing the retained liquid; and (v) applying a vacuum to open ends of the channels of the substrate at the inverted, lower end of the substrate to draw the liquid along the channels of the substrate.
摘要:
An exhaust system for a lean burn internal combustion engine comprises a particulate filter (CSF), a first NOx absorbent (NOx(1)) disposed upstream of the filter and a second NOx absorbent (NOx(2)) disposed downstream of the filter.
摘要:
A system including a compression ignition engine operable in a first, normal running mode and operable in a second mode to produce an exhaust gas having an increased level of carbon monoxide (CO) relative to the exhaust gas produced in the first mode. The system, when in use, can switch engine operation between the two modes, and the system includes an exhaust system. The exhaust system includes a supported palladium (Pd) catalyst associated with at least one base metal promoter and an optionally supported platinum (Pt) catalyst associated with and/or downstream of the Pd catalyst wherein CO is oxidised by the supported Pd catalyst during second mode operation.
摘要:
A synthetic alumino silicate zeolite catalyst containing at least one catalytically active transition metal selected from the group consisting of Cu, Fe, Hf, La, Au, In, V, lanthanides and Group VIII transition metals, which alumino silicate zeolite is a small pore aluminosilicate zeolite having a maximum ring size of eight tetrahedral atoms, wherein the mean crystallite size of the aluminosilicate zeolite determined by scanning electron microscope is >0.50 micrometer.