Abstract: A method of manufacturing a dispersion liquid for an electrode catalyst, the method comprising a step of supporting a precious metal on the surface of a carrier by an electrodeposition process using a raw material mixed solution in which a particulate carrier is dispersed in a solvent and a compound including the precious metal element is dissolved in the solvent, wherein the carrier has oxygen reduction capability and is free of precious metal elements.

Abstract: An electrode catalyst, including: a metal compound which contains an oxygen atom and at least one metal element selected from a group consisting of Group 4 elements and Group 5 elements in the long-form periodic table, and a carbonaceous material which covers at least part of the metal compound; wherein an oxygen deficiency index, which is represented as an inverse number of a peak value of a first nearest neighbor element in a radial distribution function obtained by Fourier-transforming an EXAFS oscillation in EXAFS measurement of the metal element, is 0.125 to 0.170; and a crystallinity index, which is represented as a peak value of a second nearest neighbor element in the radial distribution function, is 4.5 to 8.0.

Abstract: A method for producing an electrode catalyst, comprising a step of calcining a precursor of the electrode catalyst under conditions under which a second material defined below can change into a carbonaceous material, the precursor having been obtained by continuously hydrothermally reacting a mixture containing a first material defined below and the second material defined below in the presence of supercritical or subcritical water, wherein the first material is defined to be a metal compound composed of one or more metal elements selected from the group consisting of the elements of Group 4A and the elements of Group 5A group and one or more non-metal elements selected from the group consisting of hydrogen, nitrogen, chlorine, carbon, boron, sulfur, and oxygen, and the second material is defined to be a precursor of a carbonaceous material.

Abstract: A method for producing an electrode catalyst, comprising a step of calcining a precursor of the electrode catalyst under conditions under which a second material defined below can change into a carbonaceous material, the precursor having been obtained by hydrothermally reacting a mixture containing a first material defined below and the second material defined below in the presence of supercritical or subcritical water, or the precursor having been obtained by mixing a reaction product having been obtained by hydrothermally reacting a first material defined below in the presence of supercritical or subcritical water and the second material defined below, wherein the first material is defined to be a metal compound composed of one or more metal elements selected from the group consisting of the elements of Group 4A and the elements of Group 5A and one or more non-metal elements selected from the group consisting of hydrogen, nitrogen, chlorine, carbon, boron, sulfur, and oxygen, and the second material is d

Abstract: The invention is to provide a novel process for producing aluminum titanate-based ceramics having a low coefficient of thermal expansion. The invention is a process for producing an aluminum titanate-based ceramic comprising firing a starting material mixture containing a titanium source powder, an aluminum source powder and a silicon source powder, wherein the particle diameter corresponding to a cumulative percentage of 50% (D50) on a volume basis of the silicon source powder is not greater than 5 ?m. The invention includes the process wherein the starting material mixture further contains a magnesium source powder.

Abstract: The present invention provides a fine ?-alumina particle having a degree of ?-transformation of not less than 95%, a BET specific surface area of not less than 10 m2/g, a degree of necking of not more than 30%, and a total content of Si, Fe, Cu, Na and Mg of not more than 500 ppm.

Abstract: The invention provides a process for producing a shaped body of aluminum titanate-based ceramic such as aluminum titanate or aluminum magnesium titanate having smaller shrinkage ratio relative to a shaped body of a starting material mixture, and having a smaller coefficient of thermal expansion. The invention is a process for producing an aluminum titanate-based ceramic, comprising firing a starting material mixture containing a titanium source material and an aluminum source material, wherein the BET specific surface area of the aluminum source material is 0.1 m2/g or more and 5 m2/g or less.

Abstract: The invention is to provide a process for producing an aluminum titanate-based ceramic such as aluminum titanate or aluminum magnesium titanate having excellent thermal decomposition resistance and having a smaller coefficient of thermal expansion. The invention is a process for producing an aluminum titanate-based ceramic, comprising firing a starting material mixture containing a titanium source compound, an aluminum source compound and preferably a magnesium source compound, and a glass frit having a deformation point of 700° C. or more and/or a viscosity at 900° C. of 1.0×106 poises or more.

Abstract: Disclosed are an electrode catalyst and a method for producing an electrode catalyst. The electrode catalyst is composed of: a metal compound comprising one or more metal elements selected from the group consisting of Groups 4A and 5A, and an oxygen atom; and a carbonaceous material covering at least part of the compound, wherein the electrode catalyst has a BET specific surface area of not less than 15 m2/g and not more than 500 m2/g and a carbon coverage of not less than 0.05 and not more than 0.5 as determined by the following equation (1): carbon coverage=carbon content (% by mass)/BET specific surface area (m2/g)??(1).

Abstract: The present invention provides a method of producing an ?-alumina particle. The method of producing an ?-alumina particle comprises steps of: (1) heating a mixture containing an amorphous alumina and a pyrolyzable salt at temperature of not less than the temperature at which the pyrolyzable salt is decomposed, and less than the temperature at which the amorphous alumina transforms to ?-alumina; and (2) calcining the resultant under a partial pressure of water vapor of about 600 Pa or less.

Abstract: The invention is to provide a process for producing an aluminium titanate ceramic by firing a pre-mixture of a titania source powder, an alumina source powder and a magnesia source powder, for a short period of time. The production process of the invention comprises mixing a titania source powder and an alumina source powder followed by dry process grinding in the presence of grinding media under a grinding condition of an acceleration of at least 2G to give a pre-mixture, and firing the resulting pre-mixture. The titania source powder and the alumina source powder may be mixed together with a magnesia source powder and a silica source powder. Preferably, a vibration mill is used for the grinding. Grinding the aluminium titanate ceramic produced according to the production process of the invention gives an aluminium titanate ceramic powder.

Abstract: The invention is for obtaining aluminium titanate-based ceramics having a small BET specific surface area and having, when ground into powder, a small pore volume, by effective utilization of particulate aluminium titanate-based ceramics. A pre-mixture prepared by mixing a particulate aluminium titanate-based ceramics with a titania source and an alumina source and optionally further with a magnesia source and a silica source, or particulates of aluminium titanate-based ceramics is, as such or preferably after shaped, fired as the powder or as the molded body to produce an aluminium titanate-based ceramics.

Abstract: A method for producing an ?-alumina powder is provided. T method for producing an ?-alumina powder comprising steps of: (1) pulverizing a metal compound having a full width at half maximum (Ho) of a main peak in XRD pattern to obtain a seed crystal having a full width at half maximum (H) of the main peak in XRD pattern in the presence of pulverizing agent, (2) mixing the obtained seed crystal with an aluminum salt, (3) calcining the mixture, and wherein a ratio of H/Ho is 1.06 or more.

Abstract: The present invention provides a process for producing fine ?-alumina particles, which comprises sintering a mixture of ?-alumina precursor particles and seed crystal particles, wherein a center particle diameter of the seed crystal particles is 40 nm or less, and a ratio of the number of coarse particles having a particle diameter greater than 100 nm to the number of the total particles is 1% or less.

Abstract: The present invention provides a method for producing an ?-alumina powder. The method for producing an ?-alumina powder comprises steps of: (1) pulverizing a metal compound having a full width at half maximum (Ho) of a main peak in XRD pattern to obtain a seed crystal having a full width at half maximum (H) of the main peak in XRD pattern, (2) mixing the obtained seed crystal with an aluminum compound, (3) calcining the mixture, and wherein a ratio of H/Ho is 1.06 or more.

Abstract: A method for producing an ?-alumina powder is described. The method for producing an ?-alumina powder comprises a step of calcining an aluminum salt in the presence of a seed crystal at 600-890° C.

Abstract: A method for producing an ?-alumina particulate is described. The method for producing an ?-alumina particulate comprises steps of (Ia) and (Ib), or a step of (II): (Ia) removing water from a mixture containing water, a seed crystal and a hydrolysate obtained by hydrolysis of an aluminum compound under conditions of a pH of 5 or less and a temperature of 60° C. or less, (Ib) calcining the resulted powder, (II) calcining a mixed powder containing 75-1 wt % of an ?-alumina precursor (in terms of Al2O3) and 25-99 wt % of a seed crystal (in terms of oxide of metal component).

Abstract: The present invention provides a fine ?-alumina particle having a degree of ?-transformation of not less than 95%, a BET specific surface area of not less than 10 m2/g, a degree of necking of not more than 30%, and a total content of Si, Fe, Cu, Na and Mg of not more than 500 ppm.

Abstract: The present invention provides a process for producing fine ?-alumina particles, which comprises sintering a mixture of ?-alumina precursor particles and seed crystal particles, wherein a center particle diameter of the seed crystal particles is 40 nm or less, and a ratio of the number of coarse particles having a particle diameter greater than 100 nm to the number of the total particles is 1% or less.

Abstract: A method for producing ?-alumina powder is described. The method comprises the steps of removing water from a compound containing the following (1), (2), (3) and (4), and calcining the results: (1) ?-alumina precursor, (2) seed crystal, (3) water, (4) nitrate ion in an amount of from 2.8 to 3.3 mol per mol of aluminum (Al) contained in the ?-alumina precursor and the seed crystal.