Toyota Jidosha Kabushiki Kaisha

Kabushiki Kaisha Toyota Chuo Kenkyusho

Cataler Corporation

Kabushiki Kaisha Toyota Chuo

Akira Morikawa

Masahide Miura

Akihiko Suda

Hiromasa Suzuki

Toshitaka Tanabe

Isao Chinzei

Akiya Chiba

Naoki Takahashi

Mitsuyoshi Okada

Kosuke Iizuka

Kae Yamamura

Hirotaka Ori

Miho Hatanaka

Kae Konishi

Hideo Sobukawa

Oji Kuno

Nobuyuki Takagi

Toshio Yamamoto

Yoshihiro Goto

Takeru Yoshida

Yuki Aoki

Satoru Katoh

Yoshinori Saito

Takeshi Nobukawa

Takashi Onozuka

Kimitoshi Sato

Naoki Kumatani

Masao Watanabe

Sho Hoshino

Akemi Sato

Tadashi Suzuki

Takaaki Kanazawa

Seiji Nakahigashi

Mamoru Ishikiriyama

Yasutaka Nagai

Shigeharu Takagi

Takahiro Hayashi

Takuto Hirose

Hirohito Hirata

Hiroaki Hayashi

Masahiro Sugiura

Takao Tani

Kiyoshi Yamazaki

Satoshi Nagao

Daisuke Ochiai

Nobusuke Kabashima

Kenichirou Suzuki

Noboru Otake

Keisuke Kishita

Hirotaka Yonekura

Megumi Sasaki

Yoshiyuki Sakamoto

Kimiyasu Ono

Taizo Yoshinaga

Haruo Imagawa

Masaoki Iwasaki

Masanao Sato

Ryuta Fujii

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

A catalyst for purification of exhaust gas in which Pd-based nanoparticles and ceria nanoparticles are supported on a composite metal oxide support containing alumina, ceria, and zirconia, wherein a molar ratio (Ce/Pd) of Ce and Pd supported on the support is 1 to 8, a proximity α between Pd and Ce is 0.15 to 0.50, wherein the proximity α is determined, based on Pd and Ce distribution maps in an element mapping image of energy dispersive X-ray analysis, by the following formula (1): a Pd dispersity after a heat-resistance test at 1050° C. for 25 hours is 0.8% or more.

Catalyst for purification of exhaust gas and production method thereof

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

An oxygen storage material including a ceria-zirconia based composite oxide containing a composite oxide of ceria and zirconia, wherein

Oxygen storage material and method for producing the same

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.

A ceria-zirconia-based composite oxide containing a composite oxide of ceria and zirconia is provided, in which primary particles having a particle diameter of 1.5 to 4.5 &#x3bc;m account for, on a particle number basis, at least 50% of all primary particles in the ceria-zirconia-based composite oxide, and the molar ratio of cerium to zirconium in the ceria-zirconia-based composite oxide is between 43:57 and 55:45.

Ceria-zirconia-based composite oxide and method for producing same, and exhaust gas purification catalyst including ceria-zirconia-based composite oxide

An oxygen storage material comprises a Ce&#x2014;Zr-Ln-Ti-based composite oxide containing cerium (Ce), zirconium (Zr), a rear-earth element (Ln: excluding cerium), and titanium (Ti), wherein

An oxygen storage material comprises a La&#x2014;Co&#x2014;Al-based composite oxide containing lanthanum, cobalt and aluminum. The La&#x2014;Co&#x2014;Al-based composite oxide is in a form in which at least part of the aluminum is solid-dissolved in a La&#x2014;Co composite oxide having a perovskite structure, and has a composition expressed by the following chemical formula (1):LaCoAlO&#x2003;&#x2003;(1)where x and y are numbers satisfying conditions of 0&#x3c;x &#x3c;1 and 0&#x3c;y&#x3c;1, where x+y=0.5 to 1.5, and &#x3b4; is a number of 1.5 to 4.5.

To provide an oxygen storage material that is capable of exhibiting an excellent oxygen storage capacity (OSC) even at a low temperature of about 300&#xb0; C. and has a sufficiently high efficiency of use of cerium contained therein. An oxygen storage material including a ceria-zirconia-copper oxide-based composite oxide that contains cerium, zirconium, and copper, in which

The object of the present invention is to provide an exhaust gas purifying catalyst that can achieve high purification performance while suppressing HS emissions. The object is solved by an exhaust gas purifying catalyst in which the lower layer of the catalyst coating layer comprises a ceria-zirconia composite oxide having a pyrochlore-type ordered array structure, in which the ceria-zirconia composite oxide contains at least one additional element selected from the group consisting of praseodymium, lanthanum, and yttrium at 0.5 to 5.0 mol % in relation to the total cation amount, and the molar ratio of (cerium+additional element):(zirconium) is within the range from 43:57 to 48:52.

Exhaust gas purifying catalyst

The object of the present invention is to provide an exhaust gas purifying catalyst that can achieve high purification performance while suppressing HS emissions. The object is solved by an exhaust gas purifying catalyst in which the top layer of a catalyst coating layer comprises a ceria-zirconia composite oxide having a pyrochlore-type ordered array structure, in which the ceria-zirconia composite oxide contains at least one additional element selected from the group consisting of praseodymium, lanthanum, and yttrium at 0.5 to 5.0 mol % in relation to the total cation amount, and the molar ratio of (cerium+additional element):(zirconium) is within the range from 43:57 to 48:52.

An oxygen storage material comprises three pyrochlore-type composite oxides which are a ceria-zirconia composite oxide, a lanthana-zirconia composite oxide, and a ceria-zirconia-lanthana composite oxide, and which coexist together, wherein the oxygen storage material contains:

Oxygen storage material and method of producing the same

The object of the present invention is to provide a high-performance exhaust gas purifying catalyst that can achieve oxygen absorption/release capacity and NOx purification performance. The object is solved by an exhaust gas purifying catalyst, which comprises a ceria-zirconia composite oxide having a pyrochlore-type ordered array structure in the upstream part of the catalyst coating layer, in which the ceria-zirconia composite oxide contains at least one additional element selected from the group consisting of praseodymium, lanthanum, and yttrium at 0.5 to 5.0 mol % of the total cation amount, and has a molar ratio of (cerium+the additional element):(zirconium) of 43:57 to 48:52.

A ceria-zirconia composite oxide includes at least one of lanthanum, yttrium, and praseodymium. A rate of a total content of the at least one rare earth element to a total content of cerium and zirconium is 0.1 at % to 4.0 at %. A content of the rare earth element present in near-surface regions, which are at a distance of less than 50 nm from surfaces of primary particles of the ceria-zirconia composite oxide, accounts for 90 at % or more of the total content of the rare earth element. An average particle size of the primary particles of the ceria-zirconia composite oxide is 2.2 &#x3bc;m to 4.5 &#x3bc;m. After a predetermined durability test, the intensity ratio I(14/29) of a diffraction line at 2&#x3b8;=14.5&#xb0; to a diffraction line at 2&#x3b8;=29&#xb0; and the intensity ratio I(28/29) of a diffraction line at 2&#x3b8;=28.5&#xb0; to the diffraction line at 2&#x3b8;=29&#xb0; respectively satisfy the following conditions:(14/29)&#x2265;0.02, and(28/29)&#x2264;0.08.

Ceria-zirconia composite oxide, method for producing the same, and catalyst for purifying exhaust gas using the ceria-zirconia composite oxide

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Nagakute, Japan

Akira Morikawa