摘要:
The presently claimed invention provides a layered three-way catalyst composition for purification of exhaust gases from internal combustion engines; said catalyst comprises a first layer comprising i) palladium supported on at least one alumina component and at least one oxygen storage component; and ii) barium oxide; wherein said first layer is essentially free of strontium, and a second layer comprising: i) rhodium supported on at least one zirconia component and/ or alumina component; ii) strontium oxide and/or barium oxide; and iii) optionally, palladium supported on at least one alumina component. The presently claimed invention also provides a process for preparing the layered three-way catalyst composition which involves a technique such as incipient wetness impregnation technique(A); co-precipitation technique (B); or co-impregnation technique(C). The process includes preparing a first layer; preparing a second layer; and depositing the second layer on the first layer followed by calcination. The presently claimed invention further provides a a layered three-way catalytic article in which the three-way catalyst composition is deposited on a substrate in a layered fashion and its preparation.
摘要:
This disclosure is directed to catalyst compositions, catalytic articles for purifying exhaust gas emissions and methods of making and using the same. In particular, the disclosure relates to a catalytic article including a catalytic material on a substrate, wherein the catalytic material has a first layer and a second layer. The first layer includes a platinum group metal (PGM) component impregnated on a porous support material; and the second layer includes a rhodium component impregnated on a support material, wherein the support material is a composite material including zirconia doped with baria, alumina, or combinations thereof, wherein the zirconia-based support material includes zirconia in an amount from about 80 to about 99 wt.%.
摘要:
The invention provides an automotive catalyst composite effective for abating carbon monoxide, hydrocarbons, and NOx emission in an automotive exhaust gas stream, which includes a catalytic material on a carrier, the catalytic material including a plurality of core-shell support particles comprising a core and a shell surrounding the core, the core including a plurality of particles having a primary particle size distribution d 90 of up to about 5 µm, wherein the core particles comprise particles of one or more metal oxides, the shell including nanoparticles of one or more metal oxides, wherein the nanoparticles have a primary particle size distribution d90 in the range of about 5 nm to about 1000 nm (1 µm), and one or more platinum group metals (PGMs) on the core-shell support. The invention also provides an exhaust gas treatment system and related method of treating exhaust gas utilizing the catalyst composite.
摘要:
Described are hydrophobic materials treated with a hydrophobic source in order to enhance their hydrophobicity. The hydrophobic materials can comprise a catalyst and/or a sorbent. These hydrophobic materials have utility in a broad range of applications, e.g. separating hydrocarbons from water, removing volatile organic compounds from the ambient atmosphere, the management of oil spills, removing hydrocarbons from an exhaust gas stream, chemical separation processes to remove non-polar substances, and reducing NO x in the exhaust gas stream of a lean burn engine.
摘要:
The present invention provides a tri-metallic layered catalytic article comprising a first layer comprising palladium supported on at least one of an oxygen storage component, and an alumina component; a second layer comprising platinum and rhodium, each supported on at least one of an oxygen storage component and a zirconia component; and a substrate, wherein the weight ratio of palladium to platinum is in the range of 1.0:0.4 to 1:2. The present invention also provides a process for preparing the tri-metallic layered catalytic article, an exhaust system for internal combustion engine and use of the tri-metallic layered catalytic article for purifying a gaseous exhaust stream.
摘要:
The invention provides an automotive catalyst composite that includes a catalytic material on a carrier, the catalytic material including a plurality of core-shell support particles including a core and a shell surrounding the core, wherein the core includes a plurality of particles having a primary particle size distribution d 90 of up to about 5 µm, wherein the core particles include particles of one or more molecular sieves and optionally particles of one or more refractory metal oxides; and wherein the shell comprises nanoparticles of one or more refractory metal oxides, wherein the nanoparticles have a primary particle size distribution d90 in the range of about 5 nm to about 1000 nm (1 µm); and optionally, one or more platinum group metals (PGMs) on the core-shell support. The invention also provides an exhaust gas treatment system and related method of treating exhaust gas utilizing the catalyst composite.
摘要:
Catalysts that improve carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxides (NOx) light-off performance are provided. A catalyst composite for combustion engines, as provided herein, comprises a carrier and a first layer comprising a catalytic material on the carrier, the catalytic material comprising a palladium component supported on both a ceria-praseodymia-based oxygen storage component and a ceria-zirconia-based oxygen storage component, wherein the first layer is essentially free of alumina. The catalytic material is effective to substantially simultaneously oxidize carbon monoxide and hydrocarbons and reduce nitrogen oxides.
摘要:
An emissions treatment system for an exhaust stream of an internal combustion engine including hydrocarbons, carbon monoxide, and nitrogen oxides is provided. The disclosed system can include an exhaust conduit in fluid communication with the internal combustion engine via an exhaust manifold; a first three-way conversion catalyst (TWC-1) located downstream of the internal combustion engine in the exhaust conduit; an SCR-HCT catalyst comprising a selective catalytic reduction catalyst and a hydrocarbon trap downstream of the TWC-1 in the exhaust conduit; and a third catalyst downstream of the SCR-HCT combination in the exhaust conduit, the third catalyst comprising a platinum group metal (PGM) e.g., in an amount effective to oxidize hydrocarbons. Methods of making and using such systems and components thereof are also provided.
摘要:
Composites of mixed metal oxides for an exhaust gas purifying catalyst comprise the following co-precipitated materials by weight of the composite: zirconia in an amount in the range of 55-99%; titania in an amount in the range of 1 -25%; a promoter and/or a stabilizer in an amount in the range of 0-20%. These composites are effective as supports for platinum group metals (PGMs), in particular rhodium.
摘要:
The invention relates to a monolithic support member comprising channels with walls separating the channels from each other and having a coating deposited thereon, the non-coated channels having a polygonal cross-section profile, wherein the mean thickness dc of the coating in a corner of said cross-section profile is smaller than or equal to the mean thickness dE of the coating on an edge of said cross-section profile plus 85 micrometer; and further relates to a method for the preparation of such coated monolithic support member, the method comprising (i) providing a suspension having a viscosity in the range of from 0.5 to 100 mPas and having a solid content in the range of from 1 to 40 wt.-%, (ii) dispersing the suspension into a gas stream to obtain a gas stream comprising droplets having a droplet size in the range of from d10 greater than or equal to 1 micrometer to d90 smaller than or equal to 100 micrometer; and (iii) directing said gas stream comprising said droplet towards the monolithic support member along the axial direction of the channels of the support; and still further relates to the use of such coated monolithic support member, in particular as catalytic article in the automotive exhaust gas treatment.