Abstract:
The present disclosure generally provides catalysts, catalyst articles and catalyst systems including such catalyst articles. In particular, the catalyst composition includes a metal ion-exchanged molecular sieve ion-exchanged with at least one additional metal, which reduces the number of metal centers often present in metal promoted zeolite catalysts. Methods of making and using the catalyst composition are also provided, as well as emission treatment systems including a catalyst article coated with the catalyst composition. The catalyst article present in such emission treatment systems is useful to catalyze the reduction of nitrogen oxides in gas exhaust in the presence of a reductant while minimizing the amount of dinitrogen oxide emission.
Abstract:
Aspects of the invention pertain to catalytic articles and methods of making catalytic articles comprising a first catalytic coating comprising a platinum group metal, wherein the first catalytic coating is substantially free of Cu, Ni, Fe, Mn, V, Co, Ga, Mo, Mg, Cr and Zn; a second catalytic coating comprising a non-PGM metal, wherein the second catalytic coating is substantially free of any platinum group metal; and one or more substrates, wherein the first catalytic coating is separated from the second catalytic coating, optionally with a barrier layer.
Abstract:
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.
Abstract:
Aspects of the invention relate to a method of treating a gas stream generated by a motorcycle, the method comprising: contacting a gas stream containing hydrocarbons, carbon monoxide and nitrogen oxides and generated by a motorcycle under both rich and lean engine operating conditions with a base metal catalyst composition, thereby removing at least a part of the hydrocarbons, carbon monoxide and nitrogen oxides in gas stream. The base metal catalyst composition comprises a support including at least 10% by weight of reducible ceria, and about 3 to about 7 wt % MnO and about 8 to about 22 wt % CuO on the reducible ceria support. The base metal catalyst composition is effective to promote a steam reforming reaction of hydrocarbons and a water gas shift reaction to provide H2 as a reductant to abate NOx.
Abstract:
Catalytic articles comprising a substrate having a catalytic coating thereon, the catalytic coating comprising a catalytic layer having a thickness and an inner surface proximate to the substrate and an outer surface distal to the substrate; where the catalytic layer comprises a noble metal component on support particles and where the concentration of the noble metal component towards the outer surface is greater than the concentration towards the inner surface are highly effective towards treating exhaust gas streams of internal combustion engines. The articles are prepared via a method comprising providing a first mixture comprising micron-scaled support particles and applying the first mixture to a substrate to form a micro-particle layer; providing a second mixture comprising nano-scaled support particles and a noble metal component having an initial pH and applying the second mixture to the micro-particle layer and calcining the substrate.
Abstract:
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.
Abstract:
The present disclosure generally provides catalysts, catalyst articles and catalyst systems including such catalyst articles. In particular, the catalyst composition includes a metal ion-exchanged molecular sieve ion-exchanged with at least one additional metal, which reduces the number of metal centers often present in metal promoted zeolite catalysts. Methods of making and using the catalyst composition are also provided, as well as emission treatment systems including a catalyst article coated with the catalyst composition. The catalyst article present in such emission treatment systems is useful to catalyze the reduction of nitrogen oxides in gas exhaust in the presence of a reductant while minimizing the amount of dinitrogen oxide emission.
Abstract:
Catalytic articles comprising a substrate having a catalytic coating thereon, the catalytic coating comprising a catalytic layer having a thickness and an inner surface proximate to the substrate and an outer surface distal to the substrate; where the catalytic layer comprises a noble metal component on support particles and where the concentration of the noble metal component towards the outer surface is greater than the concentration towards the inner surface are highly effective towards treating exhaust gas streams of internal combustion engines. The articles are prepared via a method comprising providing a first mixture comprising micron-scaled support particles and applying the first mixture to a substrate to form a micro-particle layer; providing a second mixture comprising nano-scaled support particles and a noble metal component having an initial pH and applying the second mixture to the micro-particle layer and calcining the substrate.
Abstract:
The present invention relates to colloidal dispersions comprising a plurality of precious group nanoparticles, wherein about 90% or more of the precious group metal is in fully reduced form; a dispersion medium comprising a polar solvent; a water-soluble polymer suspension stabilizing agent; and a reducing agent, wherein the nanoparticle concentration is at least about 2 wt. % of the colloidal dispersion, wherein the nanoparticles have an average particle size of about 1 to about 6 nm and at least 95% of the nanoparticles have a particle size within this range; and further wherein the colloidal dispersion is substantially free of halides, alkali metals, alkaline earth metals and sulfur compounds. Methods of preparing, further processing, and using such colloidal dispersions are also provided herein.
Abstract:
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.