Kabushiki Kaisha Toyota Chuo Kenkyusho

Toyota Jidosha Kabushiki Kaisha

Cataler Corporation

Toshio Yamamoto

Masahide Miura

Akihiko Suda

Akira Morikawa

Miho Hatanaka

Satoru Katoh

Mitsuyoshi Okada

Nobuyuki Takagi

Takashi Onozuka

Naoki Takahashi

Hiromasa Suzuki

Toshitaka Tanabe

Isao Chinzei

Hirotaka Ori

Toshiyuki Tanaka

Sho Hoshino

Seiji Nakahigashi

Yasutaka Nagai

Yasuo Ikeda

Kae Yamamura

Kazuhiko Dohmae

Yusuke Akimoto

Naohiro Terao

Shinichi Matsumoto

Hideo Sobukawa

Masahiro Sugiura

Tatsuhisa Yokoi

Nobusuke Kabashima

Hirotaka Yonekura

Akiyuki Iemura

Ryouhei Kusunoki

Seiji Sasaki

Takuya Nigoro

Tetsuo Ide

A catalyst for purification of exhaust gas including a substrate, and a catalyst coat layer which is formed on a surface of the substrate and contains catalyst particles, wherein the catalyst coat layer has an average thickness ranging 25 to 150 μm, a void fraction, as determined by scanning electron microscope observation of a cross-section of the catalyst coat layer, ranging 1.5 to 8.0% by volume, 60 to 90% by volume of all voids in the catalyst coat layer are high-aspect ratio pores which have equivalent circle diameters ranging 2 to 50 μm in a cross-sectional image of a cross-section of the catalyst coat layer perpendicular to a flow direction of exhaust gas in the substrate, and which ratios of 5 or higher, the high-aspect ratio pores have an average aspect ratio ranging 10 to 50, and a noble metal is supported on the entire catalyst coat layer.

Catalyst for purification of exhaust gas

The present disclosure provides the exhaust gas purification catalyst with the improved purification performance under the high Ga condition and the transient state in which an A/F repeats rich and lean phases. The present disclosure relates to an exhaust gas purification catalyst comprising a catalyst coating layer on a substrate, the catalyst coating layer containing a noble metal, a composite oxide containing cerium oxide and zirconium oxide, and a composite oxide containing aluminum oxide, wherein in the catalyst coating layer: an average thickness of the coating layer is in a range from 20 &#x3bc;m to 100 &#x3bc;m; a porosity measured by a weight-in-water method is in a range from 50% by volume to 80% by volume; and high-aspect-ratio pores having an aspect ratio of 5 or more account for 0.5% by volume to 50% by volume of a whole volume of voids, the high-aspect-ratio pore having an equivalent circle diameter in a range from 2 &#x3bc;m to 50 &#x3bc;m in a cross-sectional image of a catalyst coating layer cross section perpendicular to an exhaust gas flow direction of the substrate and having an average aspect ratio in a range from 10 to 50, and wherein the noble metal is supported on peripheries of the voids, the composite oxide containing the cerium oxide and the zirconium oxide, and the composite oxide containing the aluminum oxide.

Exhaust gas purification catalyst

The present disclosure provides the exhaust gas purification catalyst with the improved purification performance under the high Ga condition and the atmosphere where the A/F is rich. The present disclosure relates to an exhaust gas purification catalyst including a catalyst coating layer on a substrate, the catalyst coating layer containing a noble metal and a metal oxide, wherein in the catalyst coating layer: an average thickness of the coating layer is in a range from 50 &#x3bc;m to 100 &#x3bc;m; a porosity measured by a weight-in-water method is in a range from 50% by volume to 80% by volume; and high-aspect-ratio pores having an aspect ratio of 5 or more account for 0.5% by volume to 50% by volume of a whole volume of voids, the high-aspect-ratio pore having an equivalent circle diameter in a range from 2 &#x3bc;m to 50 &#x3bc;m in a cross-sectional image of a catalyst coating layer cross section perpendicular to an exhaust gas flow direction of the substrate and having an average aspect ratio in a range from 10 to 50, and wherein when a surface side in contact with an exhaust gas in a thickness direction of the catalyst coating layer is defined as 0% and a side in contact with the substrate is defined as 100%, 80% by mass or more of a total amount of the noble metal is present in a range from 0% to 25% or more and 70% or less.

An exhaust gas purification system includes: a catalyst () provided in an exhaust gas passage of an internal combustion engine () and having a carrier containing a basic oxide and platinum carried on the carrier; a catalyst () for purifying NOx; and oxygen supply means ().

Exhaust gas purification system for internal combustion engine

A catalyst for purification of exhaust gas in which a noble metal is supported on a metal-oxide support wherein, in a oxidation atmosphere, the noble metal exists on the surface of the support in high oxidation state, and the noble metal binds with a cation of the support via an oxygen atom on the surface of the support to form a surface oxide layer and, in a reduction atmosphere, the noble metal exists on the surface of the support in a metal state, and an amount of noble metal exposed at the surface of the support, measured by CO chemisorption, is 10% or more in atomic ratio to a whole amount of the noble metal supported on the support.

Catalyst for purification of exhaust gas, regeneration method for the catalyst, and apparatus and method for purification of exhaust gas using the catalyst

A method of producing a porous composite metal oxide comprising the steps of: dispersing first metal oxide powder, which is an aggregate of primary particles each with a diameter of not larger than 50 nm, in a dispersion medium by use of microbeads each with a diameter of not larger than 150 &#x3bc;m, thus obtaining first metal oxide particles, which are 1 nm to 50 nm in average particle diameter, and not less than 80% by mass of which are not larger than 75 nm in diameter; dispersing and mixing up, in a dispersion medium, the first metal oxide particles and second metal oxide powder, which is an aggregate of primary particles each with a diameter of not larger than 50 nm, and which is not larger than 200 nm in average particle diameter, thus obtaining a homogeneously-dispersed solution in which the first metal oxide particles and second metal oxide particles are homogeneously dispersed; and drying the homogeneously-dispersed solution, thus obtaining a porous composite metal oxide.

Porous composite metal oxide and method of producing the same

An EGR cooler system according to the invention includes an EGR cooler cooling device that is provided in a coolant path which is separate from the path provided with an engine cooling system which cools coolant. The EGR cooler cooling devices cools the coolant to be supplied to a water-cooled EGR cooler. The EGR cooler system also includes a water pump that circulates the coolant within the coolant path; a bypass passage through which the coolant may bypass the EGR cooler cooling device or the water-cooled EGR cooler; and a flow control valve that regulates the amount of coolant flowing into the bypass based on the temperature of the coolant flowing through the coolant path.

EGR cooler system

A metal oxide which has a large pore volume, and is very useful as a catalyst support. An alkaline material is added to an aqueous solution in which a compound of a metal element for composing an oxide is dissolved, a resultant mixture is co-precipitated, an obtained precipitate is washed, a washed precipitate is stirred in water along with a surfactant, and is calcined. By adding the surfactant after washing, the pH is not changed so that the adding effect of the surfactant is achieved to its upper most limit, thereby obtaining a metal oxide which has a large pore volume and a large mean diameter of secondary particles, and exhibits excellent gas diffusion properties.

Metal oxide and method for producing the same, and catalyst

Disclosed are a porous material comprising particles without substantial fibrous structure and having pores, the pores having a mean pore diameter in a meson-pore region, sharp pore size distribution, and at least a part of the pores being connected three-dimensionally to form a three-dimensional network structure with random passages, the porous material preferably being of alumina and having a spongy structure or the porous material preferably being an aggregate of particles having an aspect ratio of 3 or less; a process of producing the porous material which includes a step of aging a system capable of becoming an oxide on thermal decomposition; a catalyst for exhaust gas purification having excellent NOremoval performance, high resistance against sulfur poisoning, and satisfactory high-temperature durability which comprises the porous material as a carrier having supported thereon a noble metal and an NOstorage component; and a method of exhaust gas purification using the catalyst.

Porous material process of producing the porous material, catalyst for purifying exhaust gas comprising the porous material, method of purifying exhaust gas

Disclosed are a porous material comprising particles without substantial fibrous structure and having pores, the pores having a mean pore diameter in a meso-pore region, sharp pore size distribution, and at least a part of the pores being connected three-dimensionally to form a three-dimensional network structure with random passages, the porous material preferably being of alumina and having a spongy structure or the porous material preferably being an aggregate of particles having an aspect ratio of 3 or less; a process of producing the porous material which includes a step of aging a system capable of becoming an oxide on thermal decomposition; a catalyst for exhaust gas purification having excellent NO removal performance, high resistance against sulfur poisoning, and satisfactory high-temperature durability which comprises the porous material as a carrier having supported thereon a noble metal and an NO storage component; and a method of exhaust gas purification using the catalyst.

Porous material, catalyst, method of producing the porous material and method for purifying exhaust gas

The invention features an MgAl,O,spinel powder having a specific surface area of 40 m,/g or more and an average diameter of from 3 to 20 &mgr;m and having uniform pores, and a slurry containing this spinel powder. The spinel powder is produced by milling (1) an MgAl,O,spinel powder obtained by synthesizing by the coprecipitation method with the use of hydroxide materials wherein the ratio of the average diameter of aluminum hydroxide &ldquo;D,&rdquo; to the average diameter of magnesium hydroxide &ldquo;D,&rdquo; satisfies the requirement 1.85&lE;(D,/D,) or 0.5>(D,/D,) and calcining, (2) an MgAl,O,spinel powder obtained by drying a mixture solution containing water-soluble organic substance having a boiling point of 120&deg; C. or above, converting the dried substance into a complex oxide by heating, or (3) a powder comprising as the main component an MgAl,O,spinel powder which is obtained by mechanically mixing and milling a mixture of hydroxides for producing a spinel powder to convert into a complex hydroxide, and then heating a mixture composition containing the obtained complex hydroxide with an unconverted hydroxide to thereby convert into a complex oxide.

Spinel powder and spinel slurry

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Nishikamo-gun, Japan

Toshio Yamamoto