Abstract: An exhaust gas purifying catalyst includes: a catalyst particle unit having at least noble metal with a catalytic function, first oxides on which the catalyst noble metal is supported, and second oxides covering the first oxides on which the noble metal is supported. In catalyst powder formed of an aggregate of plural pieces of the catalyst particle units, at least one type of compounds selected from the group consisting of a transition element, an alkali earth metal element, an alkali metal element, and a rare earth element, which is a promoter component, are contained.

Abstract: A three-way catalyst including a mixture of nickel and copper is provided for reducing carbon monoxide, hydrocarbon emissions, and nitrogen oxides from vehicle engine exhausts. The catalyst is impregnated onto a carrier substrate which is non-reactive with nickel and copper. When used in a vehicle exhaust gas treatment system, the nickel-copper catalyst provides improved efficiency in reducing CO, HC, and NOx emissions over the use of conventional three-way-catalysts and provides enhanced oxygen storage capacity (OSC) and water-gas-shift (WGS) functions.

Abstract: Disclosed is an exhaust gas purifying catalyst in which grain growth of a noble metal particle supported on a support is suppressed. Also, disclosed is a production process of an exhaust gas purifying catalyst, by which the above exhaust gas purifying catalyst can be produced. The exhaust gas purifying catalyst comprises a crystalline metal oxide support and a noble metal particle supported on the support, wherein the noble metal particle is epitaxially grown on the support, and wherein the noble metal particle is dispersed and supported on the outer and inner surfaces of the support. The process for producing an exhaust gas purifying catalyst comprises masking, in a solution, at least a part of the surface of a crystalline metal oxide support by a masking agent, introducing the support into a noble metal-containing solution containing a noble metal, and drying and firing the support and the noble metal-containing solution to support the noble metal on the support.

Abstract: An exhaust gas purification catalyst has a substrate, a lower catalyst layer that is formed on the substrate and contains at least one of Pd and Pt, and an upper catalyst layer that is formed on the lower catalyst layer and contains Rh. A region that does not contain the upper catalyst layer is disposed on the exhaust gas upstream side of this exhaust gas purification catalyst. The lower catalyst layer includes a front-stage lower catalyst layer on the exhaust gas upstream side and a rear-stage lower catalyst layer on the exhaust gas downstream side. The front-stage lower catalyst layer contains an oxygen storage material.

Abstract: Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogenous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.

Abstract: Provided herein are catalytic articles and methods of making same using a single coat process. The catalytic article comprises an elongated substrate monolith having a plurality of longitudinally extending passages, each passage having at least a first surface and a second surface opposite the first surface, the first and second surfaces coated with at least a first coating and a second coating, wherein the first coating comprises a first catalyst composition and overlies the second coating on the first surface, the second coating comprises a second catalyst composition and overlies the first coating on the second surface, and wherein the first catalyst composition and second catalyst composition have a difference in surface charge. The washcoat may be applied as one slurry, which then self-segregates into two coatings.

Abstract: The influence of a plurality of support oxides on coating process for ZPGM catalysts is disclosed. ZPGM catalyst samples with washcoat on suitable ceramic substrate and overcoat including a plurality of support oxides are prepared including an impregnation layer of Cu—Mn spinel or overcoat may be prepared from powder of Cu—Mn spinel with support oxide. Testing of fresh and aged ZPGM catalyst samples is developed under isothermal steady state sweep test condition. Catalyst testing allows to determine effect of a plurality of support oxides on coating processes, TWC performance, and stability of ZPGM catalysts for a plurality of TWC applications. Stability of ZPGM-TWC systems may be improved by promotion of the activity of ZPGM materials incorporating support oxides. Improvements that may be provided by the combination of support oxides with ZPGM materials in the catalyst may lead to a most effective utilization of ZPGM materials in TWC converters.

Abstract: A catalyst material including a catalyst carrier including a porous alumina support and a hindrance layer on the alumina support, the hindrance layer comprising one or more barium sulfate, strontium sulfate, zirconium sulfate, and calcium sulfate is described. The catalyst carrier further includes a rare earth oxide. The catalyst material can further comprise a platinum group metal oxide. The hindrance layer may prevent the rare earth oxide from forming a complex with the support. The catalyst material is useful for methods and systems of abating pollutants from automotive exhaust gas.

Abstract: A catalytic water gas shift process at temperatures above about 450° C. up to about 900° C. or so wherein the catalyst includes rhenium deposited on a support, preferably without a precious metal, wherein the support is prepared from a high surface area material, such as a mixed metal oxide, particularly a mixture of zirconia and ceria, to which may be added one or more of a high surface area transitional alumina, an alkali or alkaline earth metal dopant and/or an additional dopant selected from Ga, Nd, Pr, W, Ge, Fe, oxides thereof and mixtures thereof.

Abstract: Catalyst articles comprising palladium and related methods of preparation and use are disclosed. Disclosed is a catalyst article comprising a first catalytic layer formed on a substrate, wherein the first catalytic layer comprises palladium impregnated on a ceria-free oxygen storage component and platinum impregnated on a refractory metal oxide, and a second catalytic layer formed on the first catalytic layer comprising platinum and rhodium impregnated on a ceria-containing oxygen storage component. The palladium component of the catalyst article is present in a higher proportion relative to the other platinum group metal components. The catalyst articles provide improved conversion of carbon monoxide in exhaust gases, particularly under rich engine operating conditions.

Abstract: Aspects of the invention relate to hydrogenation catalysts, and hydrogenation processes using these catalysts, having particular characteristics, in terms of the amount and type of metal hydrogenation component (or catalytic constituent), as well as the support or substrate. The catalyst compositions, comprising both a noble metal and a lanthanide element on a substantially non-porous substrate, provide advantageous performance characteristics, including conversion, selectivity, and activity stability, as demanded in industrial hydrogenation and selective hydrogenation applications.

Abstract: Mixed oxides catalysts usable in particular in the full oxidation to CO2 and H2O of volatile organic compounds (VOC), in the decomposition of nitrogen protoxide to nitrogen and oxygen and the combustion of CO, H2 and CH4 off gases in fuel cells, comprising oxides of manganese, copper and La2O3 and/or Nd2O3, having a percentage composition by weight expressed as MnO, CuO, La2O3 and/or Nd2O3 respectively of 35-56%, 19-31% and 20-37%. The oxides are supported on inert porous inorganic oxides, preferably alumina.

Abstract: PROBLEM The present invention is directed to provide a catalyst for purifying exhaust gas capable of maintaining a superior catalytic performance even when the catalyst is exposed to an exhaust gas at a high temperature of 800° C. or higher. SOLUTION The catalyst for purifying exhaust gas of the present invention comprises a catalytically active component containing a noble metal and a promoter containing an oxygen storage material both being supported on a carrier. The oxygen storage material comprises cerium, zirconium, and iron, and content of iron in the oxygen storage material is 0.01% by mass or more and less than 0.70% by mass (Fe2O3 conversion) relative to the total mass of the oxygen storage material. And the oxygen storage material is (a) a complex oxide or a solid solution of iron and a metal comprising cerium and zirconium; or (b) an iron is supported on a complex oxide or a solid solution of a metal comprising cerium and zirconium.

Abstract: A catalyst for removing nitrogen protoxide from gas mixtures which contain it, comprising mixed oxides of cobalt, manganese and rare earth metals having composition expressed as percentage by weight of CoO, MnO and transition metal oxide in the lowest state of valence as follows: MnO 38-56%, CoO 22-30%, rare earth metal oxide 22-32%.

Abstract: The invention relates to a filtration structure, for filtering a gas coming from a diesel engine, which is laden with gaseous pollutants of the nitrogen oxide NOx type and with solid particles, of the particulate filter type, said filtration structure being characterized in that it includes a catalytic system comprising at least one noble metal or transition metal suitable for reducing the NOx and a support material, in which said support material comprises or is made of a zirconium oxide partially substituted with a trivalent cation M3+ or with a divalent cation M?2+, said zirconium oxide being in a reduced, oxygen-sub-stoichiometric, state.

Abstract: A denitration catalyst composition to efficiently and reductively remove nitrogen oxides from exhaust gas of a boiler or an internal combustion engine operated in lean-combustion, such as a gasoline engine, a diesel engine, by carbon monoxide and hydrocarbons; and a denitration method using the catalyst composition. In the denitration catalyst composition, a precious metal element having Rh as an essential component is supported on a zirconium oxide-based carrier formed by condensing or mixing primary particles having a zirconium oxide as a main component, and further a cerium-containing oxide (B) is present at the surface of the zirconium oxide-based carrier and at the gap of the secondary particles; and a denitration method characterized in that exhaust gas containing NO, CO and O2 is contacted with the denitration catalyst composition, under oxidative atmosphere having an air/fuel ratio of 14.7 or higher, at a temperature of 400 to 800° C.

Abstract: This invention relates to catalyst carriers to be used as supports for metal and metal oxide catalyst components of use in a variety of chemical reactions. More specifically, the invention provides a process of formulating an alpha alumina carrier that is suitable as a support for silver and the use of such catalyst in chemical reactions, especially the epoxidation of ethylene to ethylene oxide. The composition comprises at least one hydrated precursor of alpha alumina; an optional alpha alumina; and a binder. The composition is substantially free of seeding particles.

Abstract: The present invention relates to a nitrogen oxide storage catalyst comprising: a substrate; a first washcoat layer disposed on the substrate, the first washcoat layer comprising metal oxide support particles and a nitrogen oxide storage material comprising at least one metal compound selected from the group consisting of alkaline earth metal compounds, alkali metal compounds, rare earth metal compounds, and mixtures thereof, at least a portion of said at least one metal compound being supported on the metal oxide support particles; and a second washcoat layer disposed over the first washcoat layer, said second washcoat layer comprising Rh, wherein the first washcoat layer contains substantially no Rh, and wherein the second washcoat layer is disposed on 100-x % of the surface of the first washcoat layer, x ranging from 20 to 80.

Abstract: The active methanol electro-oxidation catalysts include nano-oxides of transition metals (i.e., iron, cobalt and nickel) and platinum-ruthenium alloy nano-particles. The nano-oxides of the transition metals are dispersed during synthesis of a support material, such as mesoporous carbon. The catalyst includes a support material formed from mesoporous carbon, a nano-oxide of a transition metal dispersed in the support material, and platinum-ruthenium alloy nano-particles supported on the nano-oxide of the transition metal, the platinum-ruthenium alloy nano-particles (in a 1:1 molar ratio) forming about 15 wt % of the methanol electro-oxidation catalyst, the transition metals forming about 15 wt % of the methanol electro-oxidation catalyst, and carbon and oxygen forming the balance of about 70 wt % of the methanol electro-oxidation catalyst.

Abstract: The present invention provides a slurry catalyst and a method for preparing the same, and belongs to the technical field of preparing catalyst. Particularly, the present invention provides a slurry catalyst directly used in a slurry bed reactor for synthesizing methanol and dimethyl ether and a method for preparing the same, which uses the complete liquid phase preparation from solution to slurry without the conventional slurry-producing process of firstly forming a solid catalyst and dispersing it into an inert medium after crushing and milling. This catalyst mainly comprises Cu, Zn, Al and Zr, wherein atomic ratios of each of components are Cu/Zn/(Al+Zr)=1/0.1-5/0.15-15 and Zr/Al=1:1.0-1:30, and one or two selected from the group consisting of lanthanide metals, Mn, Mo, Si, V, W, Cr, Mg, Ni, K, Pd, Rh, Ru, Re, Pt and Sr is used a promoter.

Abstract: There is described a base metal modified Cerium containing oxide materials and their application as catalysts for the oxidation of CO and HC emissions from a compression ignition/diesel engine. These materials provide effective promotion of CO and HC oxidation function in the presence or absence of PGM and are based upon OIC/OS materials having a stable cubic crystal structure, and most especially to promoted OIC/OS materials wherein the promotion is achieved by the post-synthetic introduction of non-precious metals via a basic (alkaline) exchange process.

Abstract: An Object of the patent is to remove highly reducing hydrocarbon exhausted during acceleration period, and to remove efficiently hydrocarbon even after contacting with highly reducing hydrocarbon. By using a catalyst having a higher proportion of palladium having surface charge of 2-valence or 4-valence supported than that of 0-valence by supporting palladium together with magnesium oxide, hydrocarbon exhausted from an internal combustion engine especially during acceleration period can be efficiently removed.

Abstract: The present invention relates to a catalyst for oxygenate synthesis for synthesizing an oxygenate from a mixed gas containing hydrogen and carbon monoxide, the catalyst for oxygenate synthesis containing: a component (A): rhodium, a component (B): manganese, a component (C): an alkali metal, and a component (D): a component (D1), component (D2) or component (D3), wherein the component (D1) is one or more substances selected from the group consisting of titanium, vanadium and chromium, the component (D2) is an element belonging to group 13 of the periodic table, and the component (D3) is one or more substances selected from the group consisting of magnesium and lanthanoids. According to the present invention, an oxygenate can be synthesized efficiently from a mixed gas containing hydrogen and carbon monoxide.

Abstract: A coating suspension for coating catalyst substrates comprises at least two different particulate metal and/or semi-metal oxides with a sedimentation mass (MS), characterized in that the sedimentation mass (MS) of the particulate metal and/or semi-metal oxide with the smallest sedimentation mass is between 70% and 100% of the sedimentation mass of the particulate metal and/or semi-metal oxide with the largest sedimentation mass. Further, a method for producing a coating suspension, the use of the coating suspension to coat a catalyst substrate, as well as a catalyst produced using the coating suspension are disclosed.

Abstract: Hollow porous metal oxide microspheres are provided. The microspheres may be used as a support for a catalyst, particularly an exhaust treatment catalyst for an internal combustion engine. Also provided are methods of making the microspheres, methods of using the microspheres as catalyst supports, and methods of exhaust treatment using catalyst articles comprising the microspheres.

Abstract: Improved catalysts for oxidation of sulfur dioxide which are alkali metal-promoted vanadium catalysts which are further promoted by gold. Improved methods employing such catalyst for oxidation of sulfur dioxide and for manufacture of sulfuric acid. Improved methods for multiple step oxidation of sulfur dioxide in which the last oxidation step is carried out employing improved catalysts of this invention at temperatures lower than 400° C.

Abstract: The methanol electro-oxidation catalysts include nano-oxides of rare earth metals (i.e., cesium, praseodymium, neodymium and samarium) and platinum nano-particles. The nano-oxides of the rare earth metals are dispersed during synthesis of a support material, preferably formed from mesoporous carbon. The platinum nano-particles form between about 10 wt % and about 15 wt % of the methanol electro-oxidation catalyst, the rare earth metal forms between about 10 wt % and about 15 wt % of the methanol electro-oxidation catalyst, and carbon and oxygen forming the balance (between about 70 wt % and about 80 wt %) of the methanol electro-oxidation catalyst.

Abstract: The invention relates to a catalyst for removal of nitrogen oxides from the exhaust gas of diesel engines, and to a process for reducing the level of nitrogen oxides in the exhaust gas of diesel engines. The catalyst consists of a support body of length L and of a catalytically active coating which in turn may be formed from one or more material zones. The material zones comprise a copper-containing zeolite or a zeolite-like compound. The materials used include chabazite, SAPO-34, ALPO-34 and zeolite ?. In addition, the material zones comprise at least one compound selected from the group consisting of barium oxide, barium hydroxide, barium carbonate, strontium oxide, strontium hydroxide, strontium carbonate, praseodymium oxide, lanthanum oxide, magnesium oxide, magnesium/aluminum mixed oxide, alkali metal oxide, alkali metal hydroxide, alkali metal carbonate and mixtures thereof. Noble metal may optionally also be present in the catalyst.

Abstract: A method of forming a carbon nanotube array on a substrate is disclosed. One embodiment of the method comprises depositing a composite catalyst layer on the substrate, oxidizing the composite catalyst layer, reducing the oxidized composite catalyst layer, and growing the array on the composite catalyst layer. The composite catalyst layer may comprise a group VIII element and a non-catalytic element deposited onto the substrate from an alloy. In another embodiment, the composite catalyst layer comprises alternating layers of iron and a lanthanide, preferably gadolinium or lanthanum. The composite catalyst layer may be reused to grow multiple carbon nanotube arrays without additional processing of the substrate. The method may comprise bulk synthesis by forming carbon nanotubes on a plurality of particulate substrates having a composite catalyst layer comprising the group VIII element and the non-catalytic element. In another embodiment, the composite catalyst layer is deposited on both sides of the substrate.

Abstract: An air electrode catalyst material according to an embodiment of the present invention is used in solid oxide fuel cells and includes a perovskite oxide represented by a general formula (1): AxByO3-6. A ratio x/y of the A to the B is 1.05?x/y?1.5, and a peak derived from a perovskite structure A1B1O3-? is shown in a chart obtained by an X-ray diffraction measurement, and in Raman spectra, an area of absorption peak existing between 560 cm?1 and 620 cm?1 (inclusive) is larger than that between 380 cm?1 and 440 cm?1 (inclusive).

Abstract: A metal catalyst is formed by vaporizing a quantity of metal and a quantity of carrier forming a vapor cloud. The vapor cloud is quenched forming precipitate nanoparticles comprising a portion of metal and a portion of carrier. The nanoparticles are impregnated onto supports. The supports are able to be used in existing heterogeneous catalysis systems. A system for forming metal catalysts comprises means for vaporizing a quantity of metals and a quantity of carrier, quenching the resulting vapor cloud and forming precipitate nanoparticles comprising a portion of metals and a portion of carrier. The system further comprises means for impregnating supports with the nanoparticles.

Abstract: A nanocrystalline photocatalyst for water splitting and a method for fabricating a nanocrystalline photocatalyst for water splitting. The photocatalyst comprises a structure having a specific surface area and a volume fraction of atoms located both on the surface and at the grain boundaries adapted for enhancement of a photocatalytic reaction.

Abstract: Described is a nitrogen oxide storage catalyst comprising: a substrate; a first washcoat layer provided on the substrate, the first washcoat layer comprising a nitrogen oxide storage material, a second washcoat layer provided on the first washcoat layer, the second washcoat layer comprising a hydrocarbon trap material, wherein the hydrocarbon trap material comprises substantially no element or compound in a state in which it is capable of catalyzing selective catalytic reduction, preferably wherein the hydrocarbon trap material comprises substantially no element or compound in a state in which it is capable of catalyzing a reaction wherein nitrogen oxide is reduced to N2, said catalyst further comprising a nitrogen oxide conversion material which is either comprised in the second washcoat layer and/or in a washcoat layer provided between the first washcoat layer and the second washcoat layer.

Abstract: Disclosed is an exhaust gas purifying catalyst in which grain growth of a noble metal particle supported on a support is suppressed. Also disclosed is a production process for producing an exhaust gas purifying catalyst. The exhaust gas purifying catalyst comprises a crystalline metal oxide support and a noble metal particle supported on the support, wherein the noble metal particle is epitaxially grown on the support, and wherein the noble metal particle is dispersed and supported on the outer and inner surfaces of the support. The process for producing an exhaust gas purifying catalyst comprises masking, in a solution, at least a part of the surface of a crystalline metal oxide support by a masking agent, introducing the support into a noble metal-containing solution containing a noble metal, and drying and firing the support and the noble metal-containing solution to support the noble metal on the support.

Abstract: A catalyst for the purification of exhaust gas that can be used to highly efficiently treat an exhaust gas which has moisture and fluctuates between an oxidizing atmosphere and a reducing atmosphere even after the catalyst is exposed to a high temperature is provided. The present invention relates to a catalyst for the purification of exhaust gas having a catalyst layer of catalyst components comprising a noble metal, magnesium oxide, and a refractory inorganic oxide formed on a three-dimensional structure, wherein the catalyst layer has two peaks originated from the magnesium oxide in a pore distribution obtained by mercury intrusion technique.

Abstract: Methods and kits for decomposing organophosphorus compounds in non-aqueous media at ambient conditions are described. Insecticides, pesticides, and chemical warfare agents can be quickly decomposed to non-toxic products. The method comprises combining the organophosphorus compound with a non-aqueous solution, preferably an alcohol, comprising metal ions and at least a trace amount of alkoxide ions. In a first preferred embodiment, the metal ion is a lanthanum ion. In a second preferred embodiment, the metal ion is a transition metal.

Abstract: A method for providing a catalyst on a substrate is disclosed comprising providing a first washcoat comprising a soluble washcoat salt species, a polar organic solvent, and an insoluble particulate material, contacting the first washcoat with a substrate to form a coated substrate, and then contacting the coated substrate with a second washcoat comprising an oxide or an oxide-supported catalyst to physisorb, chemisorb, bond, or otherwise adhere the oxide or the oxide-supported catalyst to the coated substrate. Also disclosed is a catalyst on a substrate comprising: a substrate; an anchor layer comprising a soluble washcoat salt species, a polar organic solvent, and an insoluble particulate material; and a second layer comprises an oxide or an oxide-supported catalyst. The catalyst on a substrate can be in either green or fired form.

Abstract: The invention relates to a catalytically active particulate filter which, in addition to the properties typical of particulate filters, has hydrogen sulphide block function, and to a process for removing nitrogen oxides and particulates from the exhaust gas of internal combustion engines operated predominantly under lean conditions (so-called “lean-burn engines”) using the inventive catalytically active particulate filter. This particulate filter comprises a filter body, a copper compound and an oxidation-catalytic active coating which comprises at least one catalytically active platinum group metal. The copper compound is in a second coating applied to the filter body. The two functional coatings may be applied to the filter body consecutive in the direction of flow, i.e. zoned, or layered one on top of the other.

Abstract: A method and system for the reduction of pollutant NOx gases from automobile exhaust, as well as a method of reforming hydrocarbons, using a self-sustaining catalyst comprising an ion conductive support, a dispersed cathodic phase, a dispersed anodic phase, and a dispersed sacrificial phase, and a method of forming the self-sustaining catalyst.

Abstract: An exhaust gas purifying catalyst that contains a first oxygen storage material on which no noble metal is supported and which has a pyrochlore phase type regular array structure, and a second oxygen storage material which has a higher oxygen storage rate and a lower oxygen storage capacity than the first oxygen storage material and on which a platinum group noble metal is supported.

Abstract: Catalytic compositions and processes are disclosed for economical conversions of lower alkane hydrocarbons. Broadly, the present invention discloses solid compositions containing mixed metal oxides that exhibit catalytic activity for ammoxidation of lower alkane hydrocarbons to produce an unsaturated nitrile in high yield. Generally, these solid oxide compositions comprise, as component elements, molybdenum (Mo), vanadium (V) niobium (Nb) and at least one active element selected from the group consisting of the elements having the ability to form positive ions. Mixed metal oxide catalytic compositions advantageously comprise one or more crystalline phases at least one of which phases has pre-determined unit cell volume and aspect ratio. Also described are methods for forming the improved catalysts having the desired crystalline structure and ammoxidation processes for conversion of lower alkanes.

Abstract: An exhaust gas purifying catalyst (1) of the present invention includes anchor/promoter simultaneous enclosure particles (5) including catalyst units (13) which contain: noble metal particles (8); and anchor particles (9) as an anchor material of the noble metal particles (8) supporting the noble metal particles (8); promoter units (14) which are provided not in contact with the noble metal particles (8) and contain first promoter particles (11) having an oxygen storage and release capacity; and an enclosure material (12) which encloses both the catalyst units (13) and the promoter units (14), and separates the noble metal particles (8) and the anchor particles (9) in the catalyst units (13) from the first promoter particles (11) in the promoter units (14). The exhaust gas purifying catalyst (1) further includes second promoter particles (6) which have the oxygen storage and release capacity, and are not enclosed in the anchor/promoter simultaneous enclosure particles (5) by the enclosure material (12).

Abstract: Provided is an exhaust gas-purifying catalyst excelling in an exhaust gas-purifying performance. The exhaust gas-purifying catalyst contains a substrate, and a catalyst layer formed on the substrate and containing a precious metal and praseodymium.

Abstract: A Rh-including catalyst layer of an upstream catalyst 3 includes Rh-doped CeZr-based mixed oxide and Rh-loading CeZr-based mixed oxide as oxygen storage/release materials. A Rh-including catalyst layer of a downstream catalyst 5 includes only Rh-doped CeZr-based mixed oxide as an oxygen storage/release material. The content of the oxygen storage/release materials included in the Rh-including catalyst layer of the upstream catalyst 3 is smaller than that of the downstream catalyst 5. The Rh-doped CeZr-based mixed oxide of the upstream catalyst 3 shows a particle size distribution having a peak particle size smaller than that of the Rh-doped CeZr-based mixed oxide of the downstream catalyst 5.

Abstract: The invention provides a catalyst for catalytically removing three components, which are carbon monoxide, hydrocarbons and nitrogen oxides, from combustion exhaust gas generated by combusting fuel at around the stoichiometric air to fuel ratio. The catalyst includes: (A) a first catalyst component including at least rhodium, platinum, or palladium in a content of 0.01 to 0.5% by weight; and (B) a second catalyst component, which is the remainder, including a composite oxide or a mixed oxide including (a) at least zirconium oxide or titanium oxide, and (b) an oxide of at least praseodymium, yttrium, neodymium, tungsten, niobium, silicon, or aluminum, wherein the content of the oxide (a) in the composite oxide or the mixed oxide is in a range of 70 to 95% by weight. The invention further provides a two-layer catalyst that includes a surface catalyst layer containing the above-mentioned catalyst.

Abstract: A composition of zirconium oxide and at least one oxide of a rare earth other than cerium is described. The zirconium oxide has a weight proportion of at least 50% and, after calcination at a temperature of 900° C. for 4 hours, the composition exhibits two populations of pores of which their respective diameters are centered. The diameter of the first pore has a value of from 20 nm to 40 nm and in the second pore has a value of from 80 nm to 200 nm. Further described is how the composition can be used for treating the exhaust gases of internal combustion engines.

Abstract: A double-layer three-way catalyst for purification of the exhaust gases from internal combustion engines which has excellent activity and thermal stability is described. The catalyst contains active aluminum oxide and a first cerium/zirconium mixed oxide which are both catalytically activated with palladium in the first layer applied to a catalyst support. In the second layer which is in direct contact with the exhaust gas, the catalyst likewise contains an active aluminum oxide and a second cerium/zirconium mixed oxide which are both catalytically activated with rhodium. The second cerium/zirconium mixed oxide has a higher zirconium oxide content than the first mixed oxide.

Abstract: The present invention relates to a 3,3?,4,4?-tetraalkyl cyclohexylbenzene represented by the general formula (1): wherein R represents an alkyl group having 1 to 4 carbon atoms, which may be easily converted into a 3,3?,4,4?-biphenyltetracarboxylic acid and a 3,3?,4,4?-biphenyltetracarboxylic dianhydride thereof, which are a starting material for a polyimide, via a 3,3?,4,4?-tetraalkylbiphenyl; and a method for producing the same.

Abstract: A catalyst support which may be used to support various catalysts for use in reactions for hydrogenation of carbon dioxide including a catalyst support material and an active material capable of catalyzing a reverse water-gas shift (RWGS) reaction associated with the catalyst support material. A catalyst for hydrogenation of carbon dioxide may be supported on the catalyst support. A method for making a catalyst for use in hydrogenation of carbon dioxide including application of an active material capable of catalyzing a reverse water-gas shift (RWGS) reaction to a catalyst support material, the coated catalyst support material is optionally calcined, and a catalyst for the hydrogenation of carbon dioxide is deposited on the coated catalyst support material. A process for hydrogenation of carbon dioxide and for making syngas comprising a hydrocarbon, esp. methane, reforming step and a RWGS step which employs the catalyst composition of the present invention and products thereof.

Abstract: A cerium-zirconium composite metal oxide having improved durability at high temperature and a stable oxygen storage capacity is provided. The cerium-zirconium composite metal oxide is characterized in that the total mole number of Ce and Zr is at least 85% based on the total mole number of metal in the composite metal oxide, a molar ratio Ce/Zr is within a range from 1/9 to 9/1, and an isoelectric point of the composite metal oxide is more than 3.5. Preferably, the molar ratio Ce/Zr is within a range from 3/7 to 7/3 and the isoelectric point is within a range from 3.8 to 5.0, and the cerium-zirconium composite metal oxide contains a rare earth metal (excluding Ce) in a concentration of less than 15% by mole based on the total mole number of metal in the composite metal oxide. Also the present invention provides a cerium-zirconium composite metal oxide, characterized in that CeO2 forms a core surrounded by ZrO2.