Toyota Jidosha Kabushiki Kaisha

Tokyo Shibaura Denki Kabushiki Kaisha

Toyota Jidoshi Kabushiki Kaisha

Akio Koyama

Shinichi Takeshima

Kohei Yoshida

Tetsuhiko Mizoguchi

Kohei Toyota Jidosha KK Yoshida

Shinichi Toyota Jidosha KK Takeshima

According to the present invention, an exhaust gas purifying catalyst is provided. The catalyst comprises a porous silica support comprising silica having a pore structure, and a perovskite-type composite metal oxide particle supported in the pore structure of the porous silica support. Further, the peak attributable to the space between silica primary particles is in the range of 3 to 100 nm in the pore distribution of the porous silica support.

Exhaust gas purifying catalyst

The present invention provides a porous composite oxide comprising an aggregate of secondary particles in the form of aggregates of primary particles of a composite oxide containing two or more types of metal elements, and having mesopores having a pore diameter of 2-100 nm between the secondary particles; wherein, the percentage of the mesopores between the secondary particles having a diameter of 10 nm or more is 10% or more of the total mesopore volume after firing for 5 hours at 600&#xb0; C. in an oxygen atmosphere.

Porous composite oxide and production method thereof

Cellulose contained in plant fiber material is hydrolyzed with the use of a pseudo-molten cluster acid as a hydrolysis catalyst to produce saccharide, most of which is glucose. After the glucose is produced, the saccharide is precipitated with the use of an organic solvent, and the saccharide including a solidified saccharide during the hydrolysis and the precipitated saccharide is separated from residues and the cluster acid.

Plant-fiber-material transformation method

A process for producing a composite metal oxide of an acidic metal oxide and a basic metal oxide, wherein the process comprises (a) providing an aqueous solution containing a colloidal particle of the acidic metal oxide and a salt of the basic metal, (b) adjusting the pH of the aqueous solution to a pH at which a part of the basic metal dissolves in the aqueous solution, the remaining of the basic metal precipitates as a hydroxide and has a positive zeta potential, and the colloidal particle of the acidic metal oxide is not dissolved and has a negative surface potential, and then maintaining this pH over a predetermined time to obtain a precursor of the composite metal oxide, and (c) drying and firing the precursor of the composite metal oxide obtained.

Production process of composite metal oxide

An automobile exhaust gas purification catalyst comprised of a support mainly comprised of ZrOin which Rh is supported as a catalyst metal preventing sintering of the support, raising the supporting efficiency, and raising the low temperature activity and a method of production of the same are provided. An automobile exhaust gas purification catalyst comprised of a support mainly comprised of ZrO, sintered under firing conditions where the as fired ZrOwill substantially not be charged in a catalyst metal supporting treatment solution, in which Rh is supported as a catalyst metal in a particle state. The method of production includes a step of charging the support mainly comprised of ZrOfired under the above firing conditions by applying at least one treatment of an acid treatment and a base treatment and a step of dipping the charged state support in the catalyst supporting treatment solution including a colloid of Rh as the catalyst metal to make the Rh colloid be adsorbed on the support.

Automobile exhaust gas purification catalyst and method of production of same

To provide a method of production of an exhaust gas purification catalyst support preventing a drop in the heat resistance of alumina or other catalyst support due to the presence of titania and provided with a sulfur poisoning suppression action by titania and an exhaust gas purification catalyst support produced by the same. A method of production of an exhaust gas purification catalyst support comprising, in a basic solution, making alumina particles adsorb ammonium ions and then bringing titania sol into contact with the alumina particle so as to make the alumina particles adsorb the titania particles. An exhaust gas purification catalyst support where at least base points on the alumina particle surfaces adsorb titania particles and the pH does not rise when immersed in an ammonium nitrate solution.

Method for production of an exhaust gas purification catalyst support and exhaust gas purification catalyst support

A porous substance producing method for producing a porous substance; by holding particles for precursors of the porous substance in micelles or inverse micelles kept in a dispersed state in a solvent with a surfactant; by agglomerating the particles of the micelles or inverse micelles to each other; and by baking the agglomerated particles. The method comprises the step of agglomerating the particles of the micelles or inverse micelles to each other by performing a treatment to resolve the dispersed state of the micelles or inverse micelles containing the particles for the precursors, with the surfactant.

Method for producing porous substances

An exhaust gas purifying catalyst is disclosed, comprising a ceria-zirconia solid solution and an iron oxide dispersed and at least partially solid-dissolved in the ceria-zirconia solid solution. A process for producing the exhaust gas purifying catalyst of the present invention is also disclosed.

Exhaust gas purifying catalyst and production process thereof

A compound oxide manufacturing method includes: dispersing micelles, in each of which an aqueous phase is formed, in an oil phase; producing primary particles of a precursor of compound oxide in the aqueous phases in the micelles; synthesizing secondary particles by causing the primary particles to aggregate; and causing the secondary particles to aggregate by breaking the dispersion state of the micelles, or by causing the micelles to coalesce. In particular, polarization is produced in each of the micelles with the use of a cation having an ionic radius larger than that of a metal ion at least when the secondary particles are synthesized in the micelles.

Compound oxide manufacturing method

The present invention relates to a production process of an exhaust gas purifying catalyst, comprising impregnating a support with a solution containing a metal salt and then drying it to load a particle of the metal salt on the support, (a) wherein a base having a less tendency to adsorb and coordinate to the metal salt particle than ammonia is incorporated into the solution to make the solution basic, and thereby the metal salt particle is caused to have a negative zeta potential; or (b) wherein an acid and a base that adsorbs and coordinates to the metal salt particle are incorporated into the solution to make the solution acidic, and thereby the metal salt particle is caused to have a positive zeta potential.

Production process of exhaust gas purifying catalyst

A catalyst carrier and exhaust gas purification catalyst superior in sintering inhibiting effect of precious metal catalyst particles are provided, that is, a catalyst carrier for carrying a precious metal comprised of a composite oxide of an electron accepting element (La) having an electron accepting property of accepting electrons from a precious metal element by approach or contact with the precious metal element (Pt) and not changing in atomic valence in an oxidation reduction reaction and of another element (Si) and, further, an exhaust gas purification catalyst comprised of this catalyst carrier on which precious metal catalyst particles are carried.

Catalyst carrier and exhaust gas purification catalyst

A method for producing a compound, in which carrier particles are made to adsorb and carry carried fine particles having a diameter smaller than that of the carrier particles. The method is characterized by comprising: a first step of charging the carrier particles or their precursors to a potential inverse to that of the carried fine particles or their precursors to adsorb the carrier particles or their precursors; and a second step of synthesizing the carried fine particles hardly soluble or their precursors, and causing the carrier particles or their precursors immediately after or during the synthesization to adsorb the hardly soluble carried fine particles or their precursors.

Method for producing compound

A method for producing a heat-resisting compound oxide in which first oxide particles are made to carry second fine particles having near charging characteristics. Said first oxide particles or their precursors are caused, before said first oxide particles or their precursors are caused to adsorb said first oxide particles or their precursors, to adsorb a predetermined acid or base so that they may be charged inversely of said second fine particles or their precursors to be adsorbed thereby. Said first oxide particles are caused to adsorb said second fine particles through said acid or base and are sintered to carry the same.

Method for producing heat-resisting compound oxides

A method for producing a heat-resisting compound oxide in which oxide particles are made to carry fine particles having a smaller particle diameter than that of said oxide particles. Said oxide particles or their precursor particles are charged to a potential inverse to that of said fine particles or their precursor particles so that said oxide particles adsorb said fine particles, and are then sintered to carry said fine particles. Thus, the fine particles can be homogeneously dispersed and firmly adhered to the surfaces of the oxide particles. As a result, the compound oxide is so excellent in heat resistance that it has little change, even subjected to a treatment such as a sintering, in the structure of the oxide particles for a carrier or in the adsorption state of the ultrafine particles, and has little thermal deterioration.

Growing community of inventors

Yokohama, Japan

Akio Koyama