Abstract:
Disclosed herein are emission treatment systems, articles, and methods for selectively reducing NOx compounds. The systems include a hydrogen generator, a hydrogen selective catalytic reduction (H2-SCR) article, and one or more of a diesel oxidation catalyst (DOC) and/or a lean NOx trap (LNT) and/or a low temperature NOx adsorber (LTNA). Certain articles may comprise a zone coated substrate and/or a layered coated substrate and/or an intermingled coated substrate of one or more of the H2-SCR and/or DOC and/or LNT and/or LTNA catalytic compositions.
Abstract:
Provided are multi-zone catalyst articles, methods of manufacturing multi-zone catalyst articles, and methods for controlling emissions in diesel engine exhaust streams with multi-zone catalyst articles, where the emission treatment system of various embodiments effectively treats diesel engine exhaust with a single multi-zone catalyst article.
Abstract:
An on-board vehicle reservoir containing an ammonia/organic solvent solution may be associated with a phase separator configured to isolate ammonia from the solution. The ammonia may be introduced into an exhaust gas stream of an internal combustion engine to function as a catalytic reductant. Ammonia may be employed to generate hydrogen via catalytic decomposition of ammonia, and the hydrogen may be introduced into an exhaust gas stream to aid catalytic reactions such as catalytic oxidation of carbon monoxide (CO) and/or hydrocarbon (HC) and/or reduction of nitrogen oxides (NO); for instance during a cold-start period.
Abstract:
An on-board vehicle reservoir containing an ammonia/organic solvent solution may be associated with a phase separator configured to isolate ammonia from the solution. The ammonia may be introduced into an exhaust gas stream of an internal combustion engine to function as a catalytic reductant. Ammonia may be employed to generate hydrogen via catalytic decomposition of ammonia, and the hydrogen may be introduced into an exhaust gas stream to aid catalytic reactions such as catalytic oxidation of carbon monoxide (CO) and/or hydrocarbon (HC) and/or reduction of nitrogen oxides (NO); for instance during a cold-start period.
Abstract:
A nitrous oxide (N2O) removal catalyst composite is described, which includes: a N2O removal catalytic material on a carrier, wherein the catalytic material comprises a platinum group metal (PGM) component on a ceria-containing support having a single phase, cubic fluorite crystal structure. The catalytic material is effective to decompose nitrous oxide (N2O) to nitrogen (N2) and oxygen (O2) and/or to reduce N2O to N2 and water (H2O) and/or (CO2) under conditions of an exhaust stream of an internal combustion engine operating under conditions that are stoichiometric or lean with periodic rich transient excursions. Methods of making and using the same are also provided.
Abstract:
Provided are multi-zone catalyst articles, methods of manufacturing multi-zone catalyst articles, and methods for controlling emissions in diesel engine exhaust streams with multi-zone catalyst articles, where the emission treatment system of various embodiments effectively treats diesel engine exhaust with a single multi-zone catalyst article.
Abstract:
Described is a catalytic article for the treatment of lean burn engine exhaust gas. The catalytic article comprises a honeycomb substrate having disposed thereon a washcoat containing one or more calcined platinum group metal components dispersed on a refractory metal oxide support located on the honeycomb substrate, the platinum group metal components having an average crystallite size in the range of about 10 to about 25 nm to provide a stable ratio of NO2 to NOx when the exhaust gas flows through the honeycomb substrate. Methods of treating exhaust gas from a lean burn engine and a system for the removal of pollutants from a lean burn engine exhaust gas stream containing NOx are also described.
Abstract:
Disclosed herein are emission treatment systems, articles, and methods for selectively reducing NOx compounds. The systems include a hydrogen generator, a hydrogen selective catalytic reduction (H2-SCR) article, and one or more of a diesel oxidation catalyst (DOC) and/or a lean NOx trap (LNT) and/or a low temperature NOx adsorber (LTNA). Certain articles may comprise a zone coated substrate and/or a layered coated substrate and/or an intermingled coated substrate of one or more of the H2-SCR and/or DOC and/or LNT and/or LTNA catalytic compositions.
Abstract:
Disclosed herein are emission treatment systems, articles, and methods for selectively reducing NOx compounds. The systems include a hydrogen generator, a hydrogen selective catalytic reduction (H2-SCR) article, and one or more of a diesel oxidation catalyst (DOC) and/or a lean NOx trap (LNT) and/or a low temperature NOx adsorber (LTNA). Certain articles may comprise a zone coated substrate and/or a layered coated substrate and/or an intermingled coated substrate of one or more of the H2-SCR and/or DOC and/or LNT and/or LTNA catalytic compositions.
Abstract:
A selective catalytic reduction (SCR) catalyst composition effective in the abatement of nitrogen oxides (NOx) is provided. The SCR catalyst composition significantly increases the conversion of NOx relative to a Cu-chabazite reference catalyst composition at any temperature, and especially at low temperatures. A catalyst article, an exhaust gas treatment system, and a method of treating an exhaust gas stream, each including the SCR catalyst composition of the invention, are also provided. The SCR catalyst composition is particularly useful for treatment of exhaust from a lean-burn engine.