Abstract: A catalyst including platinum (Pt) and a composite support. The composite support includes ZrO2/mesoporous silica sieve SBA-15. The platinum accounts for 0.01-0.3 wt. % of the catalyst. ZrO2 accounts for 5-20 wt. % of the composite support.

Abstract: A solid acid catalyst has a macropore specific volume of about 0.30-0.50 ml/g, a ratio of macropore specific volume to specific length of catalyst particles of about 1.0-2.5 ml/(g·mm), and a ratio of specific surface area to length of catalyst particles of about 3.40-4.50 m2/mm. The macropore refers to pores having a diameter of more than 50 nm. An alkylation catalyst is based on the solid acid catalyst and can be used in alkylation reactions. The solid acid catalyst and alkylation catalyst show an improved catalyst service life and/or trimethylpentane selectivity when used in the alkylation of isoparaffins with olefins.

Abstract: A composite oxide catalyst includes Ce that is a first metal, La that is a second metal, and a third metal as contained metals. The third metal is a transition metal, or a rare-earth metal other than Ce and La. A Ce content in the contained metals is higher than or equal to 5 mol % and lower than or equal to 95 mol %. An La content in the contained metals is higher than or equal to 2 mol % and lower than or equal to 93 mol %. A content of the third metal in the contained metals is higher than or equal to 2 mol % and lower than or equal to 93 mol %.

Abstract: A method of manufacturing a catalyst article, the method comprising: providing a complex of a polyphenol and a PGM, the PGM comprising rhodium and/or platinum, the polyphenol comprising an ester functional group; providing a support material; applying the complex to the support material to form a loaded support material; disposing the loaded support material on a substrate; and heating the loaded support material to form nanoparticles of the PGM on the support material.

Abstract: Embodiments of the present disclosure are directed to methods of producing a hydrogen-selective oxygen carrier material comprising combining one or more core material precursors and one or more shell material precursors to from a precursor mixture and heat-treating the precursor mixture at a treatment temperature to form the hydrogen-selective oxygen carrier material. The treatment temperature is greater than or equal to 100° C. less than the melting point of a shell material, and the hydrogen-selective oxygen carrier material comprises a core comprising a core material and a shell comprising the shell material. The shell material may be in direct contact with at least a majority of an outer surface of the core material.

Abstract: A layered catalyst structure for purifying an exhaust gas stream includes a catalyst support and a palladium catalyst layer including an atomic dispersion of palladium ions electrostatically adsorbed onto an exterior surface of the catalyst support. The catalyst support includes an alumina substrate, a first ceria layer disposed on and extending substantially continuously over the alumina substrate, and a second colloidal ceria layer formed directly on the first ceria layer over the alumina substrate. The palladium catalyst layer is formed on the exterior surface of the catalyst support by applying a palladium-containing precursor solution to the exterior surface of the catalyst support and then heating the catalyst support and the palladium-containing precursor solution. The palladium-containing precursor solution includes a positively charged palladium complex in an aqueous medium and has a pH greater than a point of zero charge of the second colloidal ceria layer.

Abstract: Provided is a method of manufacturing a supported catalyst and a supported catalyst manufactured using the same. The method may prevent the growth of catalytic metal particles by repeatedly applying heat, so the method is simpler and more economical than conventional processes. Moreover, since the support in the supported catalyst thus manufactured includes a hollow having a predetermined size, an electrode manufactured using the supported catalyst may ensure a desired electrode thickness even when used in a relatively small amount compared to the conventional technology. Moreover, water generated during operation of a fuel cell can be efficiently discharged, so desired mass transfer resistance can be exhibited, and a high electrochemically active surface area (ECSA) and superior catalytic activity can be attained.

Abstract: A method of coating a substrate with a foam is described. The method comprises: (a) introducing a foam into a substrate comprising a plurality of channels through open ends of the channels at a first end of the substrate; and (b) applying at least one of (i) a vacuum to open ends of the channels at a second end of the substrate and (ii) a pressure to the open ends of the channels at the first end of the substrate; wherein the foam comprises a particulate material, and wherein the foam is particle stabilized.

Abstract: A catalyst for wastewater treatment is disclosed. The catalyst includes a porous carrier, iron oxide impregnated into the pores of the porous carrier, and platinum impregnated into the pores and mixed with the iron oxide in the pores. Also disclosed are a method for preparing the catalyst and a method for wastewater treatment using the catalyst.

Abstract: A method for fluid catalytic cracking (FCC) of petroleum oil feedstock includes reacting the petroleum oil feedstock with a catalyst mixture in a reaction zone of an FCC unit to obtain a product stream including desulfurized hydrocarbon product, unreacted petroleum oil feedstock, and spent catalyst. During the reacting a process control system develops a process model based on data collected during the reacting, the process model characterizing a relationship among the feed rate of the base cracking catalyst, the feed rate of the FCC additive, the operating conditions, the composition of the product stream, and emissions from the reaction; and one or more of (i) a target feed rate of the base cracking catalyst, (ii) a target feed rate of the FCC additive, and (iii) one or more target operating conditions of the reaction in the reaction zone to reduce the emissions from the FCC unit and to increase a yield of the desulfurized hydrocarbon product in the product stream are determined.

Abstract: The present disclosure relates to an exhaust gas cleaning catalyst having a substrate and a catalyst coating layer coated on the substrate, in which the catalyst coating layer has an upstream-side coating layer formed from the upstream-side end portion of the exhaust gas cleaning catalyst in an exhaust gas flow direction and a downstream-side coating layer formed from the downstream-side end portion of the exhaust gas cleaning catalyst in the exhaust gas flow direction, when the upstream-side coating layer and the downstream-side coating layer overlap each other, the upstream-side coating layer is disposed on the downstream-side coating layer, and the upstream-side coating layer contains a catalytic metal and a ZrO2—CeO2 composite oxide in which Fe forms a solid solution.

Abstract: A three-way catalyst article is provided for the treatment of exhaust gas from a positive ignition engine, the catalyst article comprising: a substrate having a first layer provided thereon, wherein a second layer is provided on the first layer, wherein the first layer comprises a first metal and a first alumina, and wherein the second layer comprises a second metal and a second alumina, wherein either (i) the first metal is Pd and the second metal is Rh; or (ii) the first metal is Rh and the second metal is Pd; and wherein at least one of the first and second aluminas comprises theta alumina.

Abstract: The present invention is a process for dehydrating an alcohol to prepare corresponding olefin(s), comprising: (a) providing a feed (A) comprising at least an alcohol having at least 2 carbon atoms, and preferably at most 5 carbon atoms, or a mixture thereof optionally water, optionally an inert component, in a dehydration unit, (b) placing the feed (A) into contact with an acidic catalyst in a reaction zone of said dehydration unit at conditions effective to dehydrate at least a portion of the alcohol to make an olefin or a mixture of olefins having the same number of carbon atoms as the alcohol, (c) recovering from said dehydration unit an effluent (B) comprising: an olefin or a mixture of olefins, water, undesired by-products including aldehydes and lighter products resulting from degradation of said aldehydes under the conditions of step (b), optionally unconverted alcohol(s) if any, optionally the inert component, wherein, said feed (A)-providing step (a) comprises adding an effective amount of one

Abstract: A hexaaluminate-containing catalyst for reforming hydrocarbons. The catalyst consists of a hexaaluminate-containing phase, which consists of cobalt and at least one further element from the group consisting of La, Ba, and Sr, and an oxidic secondary phase. To prepare the catalyst, an aluminum source is brought into contact with a cobalt-containing metal salt solution, dried, and calcined. The metal salt solution additionally contains the at least one further element. The reforming of methane and carbon dioxide is great economic interest since synthesis gas produced during this process can form a raw material for the preparation of basic chemicals. In addition, the use of carbon dioxide as a starting material is important in the chemical syntheses in order to bind carbon dioxide obtained as waste product in numerous processes by a chemical route and thereby avoid emission into the atmosphere.

Abstract: A process for the elimination of heavy metals, in particular mercury and possibly arsenic and lead, present in a gaseous or liquid effluent by means of a fixed bed process using an adsorbent in the form of monolithic or supported extrudates, said extrudates being characterized by a length h and a section comprising at least three lobes. The adsorbent is composed of at least one active phase based on sulphur in the elemental form or in the form of a metallic sulphide. The process is advantageously applicable to the treatment of gas of industrial origin, synthesis gas, natural gas, gas phase condensates and liquid hydrocarbon feeds.

Abstract: The present invention relates to the field of catalysts, and more specifically to nanoparticle catalysts. Materials with high porosity which contain nanoparticles can be created by various methods, such as sol-gel synthesis. The invention provides catalytic materials with very high catalytically active surface area, and methods of making and using the same. Applications include, but are not limited to, catalytic converters for treatment of automotive engine exhaust.

Abstract: A catalyst which comprises nickel and/or cobalt supported on a support that includes a mixed oxide containing metals, such as aluminum, zirconium, lanthanum, magnesium, cerium, calcium, and yttrium. Such catalysts are useful for converting carbon dioxide to carbon monoxide, and for converting methane to hydrogen.

Abstract: The present invention relates to a catalyst composition for conversion of vegetable oils to hydrocarbon products in the diesel boiling range, comprising a porous support; Group III A or VA element in the range of 1-10 wt %; Group VI B elements in the range of 1 to 20 wt %; Group VIII B elements in range of 0.01 to 10 wt %. The present invention further provides the process for preparing the catalyst composition for conversion of vegetable oils to hydrocarbon products in the diesel boiling range. The present invention also provides the process for conversion of vegetable oils to hydrocarbon products in the diesel boiling range using the catalyst composition or discarded refinery spent hydro-treating catalyst.

Abstract: An exhaust system for a compression ignition engine comprising an oxidation catalyst for treating carbon monoxide (CO) and hydrocarbons (HCs) in exhaust gas from the compression ignition engine, wherein the oxidation catalyst comprises: a platinum group metal (PGM) component selected from the group consisting of a platinum (Pt) component, a palladium (Pd) component and a combination thereof; an alkaline earth metal component; a support material comprising a modified alumina incorporating a heteroatom component; and a substrate, wherein the platinum group metal (PGM) component, the alkaline earth metal component and the support material are disposed on the substrate.

Abstract: A method for promoting the supported catalysts using noble metal nanoparticles. Different noble metal precursors are preferentially deposited onto the supported metal catalysts through Chemical vapor deposition (CVD), and compositions so produced. Further, the promoted catalyst is used for CO and CO2 hydrogenation reactions, increasing the reaction conversion, C5+ compounds selectivity and chain growth probability. The active phase of catalyst can be either cobalt oxide, nickel oxide or their reduced format (Co0 or Ni0), and the noble metal is preferably Ruthenium.

Abstract: A method of making a metal oxide nanoparticle comprising contacting an aqueous solution of a metal salt with an oxidant. The method is safe, environmentally benign, and uses readily available precursors. The size of the nanoparticles, which can be as small as 1 nm or smaller, can be controlled by selecting appropriate conditions. The method is compatible with biologically derived scaffolds, such as virus particles chosen to bind a desired material. The resulting nanoparticles can be porous and provide advantageous properties as a catalyst.

Abstract: A method of forming a dehydrogenation catalyst support is carried out by forming a mixture comprising a bayerite aluminum hydroxide (Al(OH)3) and water into a support material. The support material is particulized. The particulized support material is compressed to a pressure of at least 5,000 psig to form a shaped body. The shaped body is calcined in pure steam at a temperature of at least 750° C. for at least 0.25 hours to form a catalyst support having an average pore diameter of 200 ? or greater. The catalyst support can then be treated with a dehydrogenation catalyst component so that the catalyst support contains the dehydrogenation catalyst component to form a dehydrogenation catalyst that can then be used by contacting a hydrocarbon feed with the catalyst within a reactor in the presence of steam under dehydrogenation reaction conditions suitable to form dehydrogenated hydrocarbon products.

Abstract: A catalyst composition for converting ethanol to higher alcohols, such as butanol, is disclosed. The catalyst composition comprises at least one alkali metal, at least a second metal and a support. The second metal is selected from the group consisting of palladium, platinum, copper, nickel, and cobalt. The support is selected from the group consisting of Al2O3, ZrO2, MgO, TiO2, zeolite, ZnO, and a mixture thereof.

Abstract: Disclosed in certain implementations is a catalysis composition that includes a metal catalyst and a support material impregnated with the metal catalyst.

Abstract: A method of fabricating composite filaments is provided. An initial composite filament including a core and a cladding (such as a Pt-group metal) is cut into smaller pieces (or is first mechanically reduced and then cut into smaller pieces). The smaller pieces of the filaments are inserted into a metal matrix, and the entire structure is then further reduced mechanically in a series of reduction steps. The process can be repeated until the desired cross sectional dimension of the filaments is achieved. The matrix can then be chemically removed to isolate the final composite filaments with the cladding thickness down to the nanometer range. The process allows the organization and integration of filaments of different sizes, compositions, and functionalities into arrays suitable for various applications.

Abstract: Disclosed in certain implementations is a catalysis composition that includes a metal catalyst and a support material impregnated with the metal catalyst.

Abstract: Disclosed in certain implementations is a catalysis composition that includes a metal catalyst and a support material impregnated with the metal catalyst.

Abstract: Embodiments of the present disclosure provide for NiPt nanoparticles, compositions and supports including NiPt nanoparticles, methods of making NiPt nanoparticles, methods of supporting NiPt nanoparticles, methods of using NiPt nanoparticles, and the like.

Abstract: The present invention relates to a catalyst for Fischer-Tropsch synthesis which has excellent heat transfer capability. This catalyst contains (1) central core particle or particles made of a heat transfer material (HTM) selected from the group consisting of a metal, a metal oxide, a ceramic, and a mixture thereof; and (2) outer particle layer which surrounds the central core particles and is attached to the surfaces of the central core particles by a binder material layer. The outer particle layer has a support and catalyst particles in a powder form containing metal particles disposed on the support. The catalyst having such a dual particle structure shows excellent heat transfer capability and, thus, exhibits high selectivity to a target hydrocarbon. Therefore, the catalyst of the present invention is useful in a fixed-bed reactor for Fischer-Tropsch synthesis for producing hydrocarbons from synthetic gas.

Abstract: Disclosed are three-way catalysts that are able to simultaneously convert nitrogen oxides, carbon monoxide, and hydrocarbons in exhaust gas emissions into less toxic compounds. Also disclosed are three-way catalyst formulations comprising palladium (Pd)-containing oxygen storage materials. In some embodiments, the three-way catalyst formulations of the invention do not contain rhodium. Further disclosed are improved methods for making Pd-containing oxygen storage materials. The relates to methods of making and using three-way catalyst formulations of the invention.

Abstract: The herein disclosed exhaust gas purification catalyst is an exhaust gas purification catalyst that is provided with a porous carrier 40 and palladium 50 supported on this porous carrier 40. The porous carrier 40 is provided with an alumina carrier 42 formed of alumina and with a CZ carrier 44 formed of a ceria-zirconia complex oxide. Barium is added to both the alumina carrier 42 and the CZ carrier 44. Here, an amount of barium added to the alumina carrier 42 is an amount that corresponds to 10 mass % to 15 mass % relative to a total mass of the alumina carrier 42 excluding the barium, and an amount of barium added to the CZ carrier 44 is an amount that corresponds to 5 mass % to 10 mass % relative to a total mass of the CZ carrier 44 excluding the barium.

Abstract: A method for preparing a catalyst having catalytically active materials selectively impregnated or supported only in the surface region of the catalyst particle using the mutual repulsive force of a hydrophobic solution and a hydrophilic solution and the solubility difference to a metal salt precursor between the hydrophobic and hydrophilic solutions. The hydrophobic solvent is a C2-C6 alcohol. The hydrophobic solvent is introduced into the catalyst support and then removed of a part of the pores connected to the outer part of the catalyst particle by drying under appropriate conditions. Then, a hydrophilic solution containing a metal salt is introduced to occupy the void spaces removed of the hydrophobic solvent, and the catalyst particle is dried at a low rate to selectively support or impregnate the catalytically active material or the precursor of the catalytically active material only in the outer part of the catalyst particle.

Abstract: A method for producing a dehydrogenation catalyst including an immersion step of impregnating an alumina layer of an alumina carrier with a platinum solution containing hexahydroxo platinate (IV) ions with an immersion method, wherein the alumina carrier has the alumina layer formed by anodic oxidation on at least a part of the surface of an aluminum support; and a calcination step of calcining the alumina carrier subjected to the immersion step to provide a dehydrogenation catalyst.

Abstract: A method of preparing catalytic materials comprising depositing platinum or non-platinum group metals, or alloys thereof on a porous oxide support.

Abstract: The present invention relates to a catalyst comprising 0.1-10 mol % Co3-xMxO4, where M is Fe or Al and x=0-2, on a cerium oxide support for decomposition of N2O in gases containing NO. The catalyst may also contain 0.01-2 weight % ZrO2. The invention further comprises a method for performing a process comprising formation of N2O. The N2O containing gas is brought in contact with a catalyst comprising 0.1-10 mol % Co3-xMxO4, where M is Fe or Al and x=0-2, on a cerium oxide support, at 250-1000° C. The method may comprise that ammonia is oxidized in presence of an oxidation catalyst and that the thereby formed gas mixture is brought in contact with the catalyst comprising the cobalt component on cerium oxide support at a temperature of 500-1000° C.

Abstract: An emission control catalyst composition comprising a supported bimetallic catalyst consisting of gold and a metal selected from the group consisting of platinum, rhodium, ruthenium, copper and nickel is disclosed. Also disclosed is a catalytic convertor comprising a substrate monolith coated with the emission control catalyst composition and a lean burn internal combustion engine exhaust gas emission treatment system comprising the catalytic convertor. A variety of processes for preparing the catalyst composition are claimed.

Abstract: Disclosed is a catalyst used for steam carbon dioxide reforming of natural gas, wherein an alkaline earth metal alone or an alkaline earth metal and a group 8B metal are supported on a hydrotalcite-like catalyst containing nickel, magnesium and aluminum. The disclosed catalyst is useful as a steam carbon dioxide reforming (SCR) catalyst of natural gas at high temperature and high pressure, while minimizing deactivation of the catalyst due to sintering of the active component nickel and deactivation of the catalyst due to coke generation at the same time. A synthesis gas prepared using the catalyst has a H2/CO molar ratio maintained at 1-2.2. A synthesis gas having a H2/CO molar ratio of 1.8-2.2 may be used as a raw material for Fischer-Tropsch synthesis or methanol synthesis and a synthesis gas having a H2/CO molar ratio of may be used as a raw material for dimethyl ether synthesis.

Abstract: A method of producing an alumina-supported cobalt catalyst for use in a Fischer-Tropsch synthesis reaction, which comprises: calcining an initial ?-alumina support material at a temperature to produce a modified alumina support material; impregnating the modified alumina support material with a source of cobalt; calcining the impregnated support material, activating the catalyst with a reducing gas, steam treating the activated catalyst, and activating the steam treated catalyst with a reducing gas.

Abstract: A method of hydroprocessing a heavy hydrocarbon feedstock using a hydroprocessing catalyst having specific properties making it effective in the hydroconversion of at least a portion of the heavy hydrocarbon feedstock to lighter hydrocarbons. The hydroprocessing catalyst comprises a Group VIB metal component (e.g., Cr, Mo, and W), a Group VIII metal component (e.g., Ni and Co) and, optionally, a potassium metal component that are supported on a support material comprising alumina. The alumina has novel physical properties that, in combination with the catalytic components, provide for the hydroprocessing catalyst. The hydroprocessing catalyst is particularly effective in the conversion of the heavy hydrocarbon feedstock. The alumina is characterized as having a high pore volume and a high surface area with a large proportion of the pore volume being present in the pores within a narrow pore diameter distribution about a narrowly defined range of median pore diameters.

Abstract: In one embodiment, the invention is to a catalyst composition for converting ethanol to higher alcohols, such as butanol. The catalyst composition comprises one or more metals and one or more supports. The one or more metals selected from the group consisting of cobalt, nickel, palladium, platinum, zinc, iron, tin and copper. The one or more supports are selected from the group consisting of Al2O3, ZrO2, MgO, TiO2, zeolite, ZnO, and mixtures thereof, wherein the catalyst is substantially free of alkali metals and alkaline earth metals.

Abstract: The present invention relates to an improvement in a process for the thermal fixation of a catalytically active component onto an alumina support and, more specifically, to an improvement in a process for the thermal fixation of a catalytically active component onto an alumina support for preparing a thermally stable catalyst for treating exhaust gas from an internal combustion engine, by means of thermally stable dispersion and fixation of the catalytically active component(s) for treating exhaust gas from an internal combustion engine, onto a surface or an internal space of the alumina support.

Abstract: A method of producing an alumina-supported catalyst for use in a Fischer-Tropsch synthesis reaction, which comprises: calcining an initial ?-alumina support material at a temperature of at least 550° C. to produce a modified alumina support material; impregnating the modified alumina support material with a source cobalt; calcining the impregnated support material at a temperature of 700° C. to 1200° C., and activating the catalyst.

Abstract: The invention concerns a process for the oxidation of organic compounds contained in a gas stream and comprises the step of introducing the gas stream containing the organic compounds together with sufficient oxygen to effect the desired amount of oxidation into an oxidation reactor containing an oxidation catalyst and maintaining the temperature of said gas stream at a temperature sufficient to effect oxidation, characterised in that the oxidation catalyst contains at least 0.01% by weight of ruthenium, cobalt or manganese.

Abstract: An exhaust emission control catalyst disclosed herein is equipped with a rhodium catalytic layer and a platinum catalytic layer, and is characterized in that a relationship between a mole average (X) of a Pauling's electronegativity that is calculated as to elements included in the rhodium catalytic layer except platinum group elements and oxygen and a mole average (Y) of a Pauling's electronegativity that is calculated as to elements included in the platinum catalytic layer except platinum group elements and oxygen is 1.30?X?1.45 and 1.47?Y?2.0. According to this exhaust emission control catalyst, an interlayer transfer of platinum and/or rhodium and the alloying of platinum and/or rhodium are suppressed during use of the catalyst, and high exhaust gas purification performance can be exerted.

Abstract: Disclosed is a gas purifying catalyst for an internal combustion engine comprising: a carrier and a catalyst layer formed on the carrier, the catalyst layer including a first catalyst, a second catalyst and a third catalyst. The first catalyst comprises Pd supported in a first support, the first support comprising alumina. The second catalyst comprises Rh supported in a second support, the second support comprising a complex oxide of ceria-zirconia. The third catalyst comprising Pd supported in a third support, the third support comprising a complex oxide of ceria-zirconia.

Abstract: The present invention relates to catalysts, to processes for making catalysts and to chemical processes employing such catalysts. The multifunctional catalysts are preferably used for converting acetic acid and ethyl acetate to ethanol. The catalyst is effective for providing an acetic acid conversion greater than 20% and an ethyl acetate conversion greater than 0%. The catalyst comprises a precious metal and one or more active metals on a modified support. The modified support includes a metal selected from the group consisting of tungsten, vanadium, and tantalum, provided that the modified support does not contain phosphorous.

Abstract: Solutions to the problem of washcoat and/or overcoat adhesion loss of ZPGM catalyst on metallic substrates are disclosed. Present disclosure provides an enhanced process for improving WCA to metallic substrates of ZPGM catalyst systems. Reduction of WCA loss and improved catalyst activity may be enabled by the selection of processing parameters determined from variation of rheological properties by the solid content of the overcoat slurry and variation of the overcoat slurry particle size distribution to produce desirable homogeneity, specific loading, and adherence of the coating on metallic substrates. Processing parameters may be applied to a plurality of metallic substrates of different geometries and cell densities.

Abstract: An exhaust gas purification catalyst includes a catalytic layer containing a particle component A-1 and a particle component A-2 with different catalytic metal contents, each of which is composed of catalytic-metal-doped CeZr-based mixed oxide powder. The particle component A-1 having the lower catalytic metal content is supported on a particle component B composed of Zr-based-oxide-supported alumina powder, and the particle component A-2 having the higher catalytic metal content is supported on a particle component C composed of CeZr-based mixed oxide powder in which catalytic metal is not solid-dissolved.

Abstract: A catalytically active particulate filter is proposed which is suitable for use in an exhaust gas cleaning system for diesel engines. The particulate filter removes diesel soot particles from the exhaust gas and is also effective to oxidize carbon monoxide and hydrocarbons and to convert nitrogen monoxide at least proportionally into nitrogen dioxide. The particulate filter comprises a filter body (3) and two catalytically active coatings (1) and (2) which contain platinum and palladium, or platinum or palladium respectively, wherein the platinum content of the second catalytically active coating (2) is higher than the platinum content of the first catalytically active coating (1).

Abstract: An exhaust gas-purifying catalyst includes a support provided with one or more through-holes through which exhaust gas flows, and a catalytic layer supported by the support and containing an oxygen storage material. The exhaust gas-purifying catalyst includes a first section to which the exhaust gas is supplied, and a second section to which the exhaust gas having passed through the first section is supplied. The catalytic layer includes a layered structure of a first catalytic layer containing platinum and/or palladium and a second catalytic layer containing rhodium in the first catalytic section and further includes a third layer containing rhodium in the second section. The second section is smaller in oxygen storage material content per unit volumetric capacity than the first section.