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: A structurally promoted, precipitated, Fischer-Tropsch catalyst that exhibits an RCAI-10 of 0-2.8 and/or produces less than 6 wt % fines after 5 hours ASTM Air Jet Attrition testing, due to formation via: preparing a nitrate solution by forming at least one metal slurry and combining the at least one metal slurry with a nitric acid solution; combining the nitrate solution with a basic solution to form a precipitate; structurally promoting the precipitate with at least one source of silicon to form a promoted mixture, wherein promoting comprises combining the precipitate with (a) silicic acid and one or more component selected from the group consisting of non-crystalline silicas, crystalline silicas, and sources of kaolin or (b) a component selected from the group consisting of non-crystalline silicas and sources of kaolin, in the absence of silicic acid; and spray drying the promoted mixture to produce catalyst having a desired particle size.

Abstract: A TiO2-containing composite nano-powder catalyst obtained by combining a titanium-based metal ceramic compound in powder form with a mixing solution containing compound(s) of a platinum group metal and/or a non-noble metal, drying the resulting mixture, and then performing oxidative thermal decomposition on the dried mixture. This catalyst also can be used as a support to further support platinum group metal(s) and/or non-noble metal(s) to obtain another composite nano-powder catalyst. A method for preparing a TiO2-containing composite nano-powder catalyst is also disclosed.

Abstract: The present invention relates to an Fe-modified perovskite-type catalyst, a method for preparing same and a method for preparing a synthesis gas by a combined reforming reaction using same. More particularly, it relates to a catalyst for a combined natural gas/steam/carbon dioxide reforming reaction having a perovskite structure with La and Sr introduced at the A site and Ni and Fe introduced at the B site with specific molar ratios and a method for producing a synthesis gas for Fischer-Tropsch synthesis or methanol synthesis using the catalyst by the combined reforming reaction. The catalyst of the present invention exhibits higher carbon dioxide conversion rate, significantly reduced catalyst deactivation caused by carbon deposition and improved long-term catalyst stability and activity, as compared to the existing catalyst for reforming reaction prepared by the impregnation method.

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: 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: 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: A noble metal-based electrocatalyst comprises a bimetallic particle comprising a noble metal and a non-noble metal and having a polyhedral shape. The bimetallic particle comprises a surface-segregated composition where an atomic ratio of the noble metal to the non-noble metal is higher in a surface region and in a core region than in a sub-surface region between the surface and core regions. A method of treating a noble metal-based electrocatalyst comprises annealing a bimetallic particle comprising a noble metal and a non-noble metal and having a polyhedral shape at a temperature in the range of from about 100° C. to about 1100° C.

Abstract: The present invention relates to a structured catalyst based on sintered metal fibers (SMF) coated by a non-acidic metal oxide layer impregnated with Pd and Agnanopartides, characterized in that the ratio of the Pd:Ag is 1:1 to 10:1, as well as the use of such a catalyst in selective catalytic hydrogenations of organic compounds.

Abstract: Disclosed is a catalyst which can convert ammonia contained in exhaust gas from an engine of a vehicle equipped with a Urea-SCR (Urea-Selective Catalytic Reduction) system, to nitrogen, and a method for preparating the same. The catalyst can convert ammonia which is failed to participate in a conversion reaction of NOx to N2 and slipped out of the SCR catalyst, to nitrogen via a SCO (Selective Catalytic Oxidation) reaction, before the ammonia is released to the air.

Abstract: A method of generating electrical power includes flowing hydrogen across an anode, splitting the hydrogen into protons and electrons using a catalyst attached to the anode, directing the electrons to a circuit to produce electrical power, flowing oxygen across a cathode, splitting the oxygen molecules into oxygen atoms using a cathode catalyst, passing the protons through an electrolyte to the cathode, and combining the protons with oxygen to form water. The cathode catalyst includes a plurality of nanoparticles having terraces formed of platinum, and corner regions and edge regions formed of a second metal.

Abstract: Process for the steam reforming of hydrocarbons comprising contacting a feed gas with a catalyst consisting of an active compound in the form of an alloy of nickel and one of iridium, rhodium and ruthenium, on a support comprising alumina, zirconia, magnesia, titania, or combinations thereof.

Abstract: A method and article of manufacture including a catalytic substrate with a surface layer providing balanced active sites for adsorption/dissociation of H2 and adsorption of OHad for use in AFCs.

Abstract: Stabilized palladium (+1) compounds to mimic rhodium's electronic configuration and catalytic properties are disclosed. Palladium (+1) compounds may be stabilized in perovskite or delafossite structures and may be employed in Three-Way Catalysts (TWC) for at least the conversion of HC, CO and NOx, in exhaust gases. The TWC may include a substrate, a wash-coat and, a first impregnation layer, a second impregnation layer and an over-coat. The second impregnation layer and the over-coat may include palladium (+1) based compounds as catalyst.

Abstract: A fuel cell membrane-electrode assembly having a fuel electrode and an oxidant electrode has a non-supported-catalyst containing catalyst layer that contains a metal catalyst nanoparticle of 0.3 nm to 100 nm in primary particle diameter that is not supported on a support, and an electrochemically active surface area of the metal catalyst nanoparticle is 10 m2/g to 150 m2/g, and a layer thickness of the non-supported-catalyst containing catalyst layer is less than or equal to 10 ?m.

Abstract: The present invention relates to a catalyst composition comprising a carrier substrate, a layer (i) coated on said carrier substrate comprising at least one precious group metal, a layer (ii) comprising Rh, and a layer (iii) comprising Pd and/or Pt and being substantially free of Ce, Ba and Rh, wherein the layer (iii) has a lower weight than the layer (i) or the layer (ii). Furthermore, the present invention relates to a method for treating an exhaust gas stream using said catalyst composition.

Abstract: An electrocatalyst suitable for use in a fuel cell, the electrocatalyst comprising: palladium, iridium and an anionic polymer.

Abstract: A method of forming a Fischer-Tropsch catalyst by providing at least one metal nitrate solution, combining each of the at least one metal nitrate solutions with a precipitating agent whereby at least one catalyst precipitate is formed, and incorporating a strong base during precipitation, subsequent precipitation, or both during and subsequent precipitation. Catalysts produced via the disclosed method are also provided.

Abstract: A porous oxide catalyst includes porous oxide, and an oxygen vacancy-inducing metal which induces an oxygen vacancy in a lattice structure of a porous metal oxide.

Abstract: The present invention relates to a particle filter comprising a porous carrier body, an SCR active component and an oxidation catalyst, wherein the SCR active component is present as coating on the exhaust-gas entry surface and the inner surface of the porous carrier body and the oxidation catalyst as coating on the exhaust-gas exit surface of the porous carrier body. According to the invention the oxidation catalyst changes its function depending on operating conditions. In normal operation it serves as NH3 slip catalyst for oxidizing excess NH3 and during filter regeneration it operates according to the 3-way principle for converting NOx and CO. The invention also relates to a method for producing the particle filter, the use of the particle filter for treating exhaust gases from the combustion of fossil, synthetic or biofuels as well as an exhaust-gas cleaning system which contains the particle filter according to the invention.

Abstract: Disclosed herein is a method of preparing an alloy catalyst for fuel cells, which is suitable for mass production and can reduce manufacturing costs. The method includes vaporizing at least two catalyst precursors in separate vaporizers; supplying the at least two vaporized catalyst precursors to a reactor while preventing contact therebetween; and synthesizing an alloy catalyst in the reactor. The method can prepare an alloy catalyst through a one-step process unlike typical multi-step methods for preparing catalysts, and can prepare an alloy catalyst at a much lower temperature than the typical methods for preparing alloys, thereby enabling mass production and cost reduction.

Abstract: The present invention is directed to a catalyst suitable for catalyzing a Fischer-Tropsch reaction, said catalyst comprising cobalt metal supported on zinc-oxide and having the following particle size distribution by volume: <10% having a particle size below 1 micron, 70-99% having a particle size between 1 and 5 micron, and <20% having a particle size above 5 micron.

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: A catalyst composition is provided comprising a homogeneous solid mixture having ordered directionally aligned tubular meso-channel pores having an average diameter in a range of about 1 nanometer to about 15 nanometers, wherein the homogeneous solid mixture is prepared from a gel formed in the presence of a solvent, modifier, an inorganic salt precursor of a catalytic metal, an inorganic precursor of a metal inorganic network, and a templating agent. The templating agent comprises an octylphenol ethoxylate having a structure [I]: wherein “n” is an integer having a value of about 8 to 20.

Abstract: In one example embodiment, a core-shell type platinum-containing catalyst is allowed to reduce the amount of used platinum and has high catalytic activity and stability. In one example embodiment, the core-shell type platinum-containing catalyst includes a core particle (with an average particle diameter R1) made of a non-platinum element and a platinum shell layer (with an average thickness ts) satisfying 1.4 nm?R1?3.5 nm and 0.25 nm?ts?0.9 nm. The core particle includes an element satisfying Eout?3.0 eV, where average binding energy relative to the Fermi level of 5d orbital electrons of platinum present on an outermost surface of the shell layer is Eout. In a fuel cell including a platinum-containing catalyst which contains a Ru particle as a core particle, the output density at a current density of 300 mA/cm2 is 70 mW/cm2 or over, and an output retention ratio is approximately 90% or over.

Abstract: A hydrogen storage alloy unit comprises a porous body 7 having a large number of holes (spaces) 9 allowing hydrogen atoms to pass through, and a hydrogen storage alloy covering a surface of the porous body 7, inclusive of surfaces of the holes thereof. The hydrogen storage alloy includes a hydrogen storage base formed of a hydrogen storage material, and a catalytic layer covering a surface of the hydrogen storage base. The porous body 7 is formed of an assembly of hydrogen storage fibers 8 formed by vapor-depositing the hydrogen storage alloy onto nanofibers.

Abstract: A process for producing a ringlike oxidic shaped body by mechanically compacting a pulverulent aggregate introduced into the fill chamber of a die, wherein the outer face of the resulting compact corresponds to that of a frustocone.

Abstract: Ammonia oxidation catalyst being superior in heat resistance and capable of suppressing by-production of N2O and leakage of ammonia. The ammonia oxidation catalyst (AMOX) removes surplus ammonia, in selectively reducing nitrogen oxides by adding urea or ammonia and using a selective catalytic reduction (SCR) catalyst, into exhaust gas, wherein the ammonia oxidation catalyst is made by coating at least two catalyst layers having a catalyst layer (lower layer) including a catalyst supported a noble metal element on a composite oxide (A) having titania and silica as main components, and a catalyst layer (upper layer) including a composite oxide (C) consisting of tungsten oxide, ceria, and zirconia, at the surface of an integral structure-type substrate, wherein a composition of the composite oxide (C) is tungsten oxide: 1 to 50% by weight, ceria: 1 to 60% by weight, and zirconia: 30 to 90% by weight.

Abstract: The disclosed technology relates to nanotechnology, petrochemistry, gas chemistry, coal chemistry, in particular to a catalyst based on carbon nanotubes for synthesis of hydrocarbons from CO and H2 and a preparation method thereof. The carbon nanotubes fixed in the catalyst pellet pores improve mass and heat transfer in the catalyst pellet and the catalyst bed.

Abstract: The invention relates to a method for producing a catalyst, wherein the catalyst has a high activity and selectivity with regard to the oxidation of CO and NO. The invention also relates to the catalyst produced using the method according to the invention, the use of the catalyst as oxidation catalyst as well as a catalyst component which contains the catalyst according to the invention. Finally, the invention is directed towards an exhaust-gas cleaning system which comprises the catalyst component containing the catalyst according to the invention.

Abstract: In a process for the regeneration of a coked metal-containing catalyst, the coked catalyst is contacted in a regeneration zone with an atmosphere which contains carbon dioxide and carbon monoxide at a temperature of at least 400° C.

Abstract: A metal oxide-supported nickel catalyst includes a matrix containing a metal oxide and catalytic sites distributed throughout the matrix and having an intricate interface with the matrix, in which the catalytic sites are selected from the group consisting of nano-nickel(0) domains and nano-nickel(0)-A(0) alloy domains. Also disclosed are a method for preparing this catalyst and a method for using it to produce carbon monoxide and hydrogen by partial oxidation of a C1-C5 hydrocarbon.

Abstract: Provided are a method of preparing an electrocatalyst for fuel cells in a core-shell structure, an electrocatalyst for fuel cells having a core-shell structure, and a fuel cell including the electrocatalyst for fuel cells. The method may be useful in forming a core and a shell layer without performing a subsequent process such as chemical treatment or heat treatment and forming a core support in which core particles having a nanosize diameter are homogeneously supported, followed by selectively forming shell layers on surfaces of the core particles in the support. Also, the electrocatalyst for fuel cells has a high catalyst-supporting amount and excellent catalyst activity and electrochemical property.

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: A catalyst has a long life span and efficiently separates hydrogen from water. A first metal element (Ni, Pd, Pt) for cutting the combination of hydrogen and oxygen and a second metal element (Cr, Mo, W, Fe) for helping the function of the first metal element are melted in alkaline metal hydroxide or alkaline earth metal hydroxide to make a mixture heated at a temperature above the melting point of the hydroxide to eject fine particles from the liquid surface, bringing steam into contact with the fine particles. Instead of this, a mixture of alkaline metal hydroxide and metal oxide is heated at a temperature above the melting point of the alkaline metal hydroxide to make metal compound in which at least two kinds of metal elements are melted, and fine particles are ejected from the surface of the metal compound to be brought into contact with steam.

Abstract: A process for preparing a slurry catalyst is provided. The slurry catalyst is prepared from at least a Group VIB metal precursor and optionally at least a Promoter metal precursor selected from Group VIII, Group IIB, Group IIA, Group IVA metals and combinations thereof. The slurry catalyst comprises a plurality of dispersed particles in a hydrocarbon medium having an average particle size ranging from 1 to 300 ?m. The slurry catalyst is then mixed with a hydrogen feed at a pressure from 1435 psig (10 MPa) to 3610 psig (25 MPa) and a temperature from 200-800° F. at 500 to 15,000 scf hydrogen per bbl of slurry catalyst for a minute to 20 hours, for the slurry catalyst to be saturated with hydrogen providing an increase of k-values in terms of HDS, HDN, and HDMCR of at least 15% compared to a slurry catalyst that is not saturated with hydrogen.

Abstract: The invention relates to a method for preparation of ruthenium-based carbene catalysts with a chelating alkylidene ligand (“Hoveyda-type catalysts”) by reacting a penta-coordinated ruthenium (II)-alkylidene complex of the type (L) (Py)X1X2Ru(alkylidene) with a suitable olefin derivative in a cross metathesis reaction. The method delivers high yields and is conducted preferably in aromatic hydrocarbon solvents. The use of phosphine-containing Ru carbene complexes as starting materials can be avoided. Catalyst products with high purity, particularly with low Cu content, can be obtained.

Abstract: A process for preparing a catalyst precursor includes, in a first preparation step, impregnating a particulate catalyst support with an organic metal compound in a carrier liquid. The metal of the organic metal compound is an active catalyst component. An impregnated intermediate is formed, and is calcined to obtain a calcined intermediate. Thereafter, in a second preparation step, the calcined intermediate from the first preparation step is impregnated with an inorganic metal salt in a carrier liquid. The metal of the inorganic metal salt is an active catalyst component. An impregnated support is obtained, and is calcined, to obtain the catalyst precursor. The metal is in particular cobalt. The precursor is reduced, in particular with hydrogen, to obtain the active catalyst. Also claimed is a process for the hydrogenation of CO, as well as a process for the hydrogenation of an organic compound using the so-prepared catalyst.

Abstract: Catalyst articles comprising substantially only a palladium precious metal component in a first catalytic layer and a rhodium component in a second catalytic layer and related methods of preparation and use are disclosed. Also disclosed is a catalyst article comprising a first layer formed on a carrier substrate, wherein the first layer comprises a refractory metal oxide and has a surface that is substantially uniform; a second layer formed on the first layer, wherein the second layer comprises i) an oxygen storage component that is about 50-90% by weight of the second layer and ii) a palladium component in an amount of about 2-5% by weight of the second layer, wherein the palladium component is substantially the only platinum group metal component, and a palladium-free third layer comprising a rhodium component supported on a thermostable oxygen storage component which is about 80-99% by weight of the second layer. One or more improved properties are exhibited by the catalyst article.

Abstract: A method of preparing a nitrogen containing electrode catalyst by converting a high surface area metal-organic framework (MOF) material free of platinum group metals that includes a transition metal, an organic ligand, and an organic solvent via a high temperature thermal treatment to form catalytic active sites in the MOF. At least a portion of the contained organic solvent may be replaced with a nitrogen containing organic solvent or an organometallic compound or a transition metal salt to enhance catalytic performance. The electrode catalysts may be used in various electrochemical systems, including a proton exchange membrane fuel cell.

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: A CO shift catalyst according to the present invention is one that reforms carbon monoxide (CO) in gas. The CO shift catalyst includes: active ingredients including one of molybdenum (Mo) and iron (Fe) as a main ingredient and one of nickel (Ni) and ruthenium (Ru) as an accessory ingredient; and one or at least two oxides of titanium (Ti), zirconium (Zr), and cerium (Ce) as a carrier supporting the active ingredients. The CO shift catalyst can be used for a CO shift reactor 20 that converts CO in gasified gas 12 produced in a gasifier 11 into CO2.

Abstract: A process for producing an olefin oxide which comprises reacting an olefin with oxygen in the presence of a catalyst comprising a copper oxide and a ruthenium oxide on a porous support.

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: An improved process for preparing a slurry catalyst for the upgrade of heavy oil feedstock is provided. In the process, high shear mixing is employed to generate an emulsion containing droplets of metal precursor in oil with droplet sizes ranging from 0.1 to 300 ?m. The emulsion is subsequently sulfided with a sulfiding agent, or in-situ in a heavy oil feedstock to form a slurry catalyst. The in-situ sulfidation in heavy oil is under sufficient condition for the heavy oil feedstock to generate the sulfiding source needed for the sulfidation.

Abstract: A process for preparing an improved slurry catalyst for the upgrade of heavy oil feedstock is provided. The process comprises providing at least a metal precursor in solution comprising at least two different metal cations in its molecular structure, with at least one of the metal cations is a Group VIB metal cation; sulfiding the metal precursor with a sulfiding agent in solution forming a catalyst precursor; and mixing the catalyst precursor with a hydrocarbon diluent to form the slurry catalyst. In one embodiment, the at least a metal precursor comprising at least two different metal cations is prepared by combining and reacting at least one Group VIB metal compound with at least a Promoter metal compound selected from Group VIII, Group IIB, Group IIA, Group IVA metals and combinations thereof.

Abstract: An improved process to make a slurry catalyst for the upgrade of heavy oil feedstock is provided. The sulfiding of the metal precursor/catalyst precursor is carried out at least twice (“enhanced sulfiding”) in the improved process to form a slurry catalyst with improved surface area and porosity value. The slurry catalyst under an enhanced sulfiding scheme is characterized as having increased catalytic activities over a slurry catalyst without an enhanced sulfidation step.

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: The present invention relates to metal oxide particles having cores comprising larger molar amounts of zirconia than of ceria, and surface layers comprising larger molar amounts of ceria than of zirconia. Further, the present invention relates to a method for preparing the particles. The method comprises preparing a solution comprising zirconia sol and ceria sol, adjusting the pH of the solution within ±0.5 on the basis of the isoelectric point of zirconia, and aggregating zirconia and then aggregating ceria around the aggregated zirconia from the solution to make aggregates. Furthermore, the present invention relates to an exhaust gas purifying catalyst comprising the metal oxide particles, and a noble metal carried by the metal oxide particles.