Toyota Jidosha Kabushiki Kaisha

Cataler Corporation

Kabushiki Kaisha Toyota Chuo Kenkyusho

Masaaki Kawai

Takahiko Fujiwara

Takeru Yoshida

Yuki Aoki

Naoki Takahashi

Kenji Sakurai

Hiroki Ichinose

Toshitaka Tanabe

Shingo Sakagami

Miho Hatanaka

Mitsuyoshi Okada

Kunihiko Nakata

Hiroaki Mizoguchi

Yuji Yabuzaki

Yasunori Sato

Chihiro Kasuya

Tomohito Mizukami

Hideaki Ueno

Atsunori Hirata

Tomoaki Sunada

Masahiro Nakahara

Singo Sakagami

An exhaust gas purification catalyst device has catalyst coating layers, which extend from the upstream side to the downstream side of the exhaust gas flow. The catalyst coating layers each have at least three zones present in order from the upstream side to the downstream side of the exhaust gas flow, and each of these at least three zones is an oxidation catalyst zone or a reduction catalyst zone. In the uppermost layer of an oxidation catalyst zone, the total number of atoms of platinum and palladium is greater than the number of atoms of rhodium; in the upper most layer of a reduction catalyst zone, the number of atoms of rhodium is greater than the total number of atoms of platinum and palladium. The oxidation catalyst zones and the reduction catalyst zones alternate at least twice in the exhaust gas flow direction.

Exhaust gas purification catalyst device

An exhaust gas purifying catalyst includes a substrate that defines an exhaust gas passage; a lower catalyst layer formed over the substrate, and an upper catalyst layer formed over the lower catalyst layer. The lower catalyst layer has a lower catalytic precious metal that contains at least one of Pt and Pd, and a lower-layer carrier that supports the lower catalytic precious metal. The upper catalyst layer has an upper catalytic precious metal that contains Rh, and an upper-layer carrier that supports the upper catalytic precious metal. The upper-layer carrier includes an inorganic mixed oxide that contains Ce, Zr, Al, Nd, and at least one element selected from the group consisting of rare earth elements other than Ce and alkaline earth elements. The Nd is unevenly distributed in covering layers that covers surfaces of interior regions within the inorganic mixed oxide.

Exhaust gas purifying catalyst

A catalyst for purifying exhaust gases includes a substrate, and a catalytic layer. The catalytic layer includes a lower catalytic layer, a first upper catalytic layer, and a second upper catalytic layer. The lower catalytic layer being loaded with Pd and/or Pt is formed on the substrate. The first upper catalytic layer being loaded with Pd covers an upstream side of the lower catalytic layer, and exhibits a concentration of loaded Pd that falls in a range of from 4.5 to 12% by mass when the entirety of the first upper catalytic layer is taken as 100% by mass. The second upper catalytic layer being loaded with Rh covers a downstream side of the lower catalytic layer.

Catalyst for converting exhaust gases

An object of the present invention is to provide an exhaust gas purifying apparatus for an internal combustion engine which can successfully achieve a good balance between reduction of exhaust emission and removal of particulate matter PM. An upstream side three-way catalystwithout OSC materials is disposed in an exhaust pipeimmediately below an exhaust manifoldof an internal combustion engine. A particulate filter (PM filter)for trapping the particulate matter PM contained in exhaust gas is disposed at a downstream side of the upstream side three-way catalyst. A downstream side three-way catalystwith the OSC materials is disposed at a downstream side of the PM filter

Exhaust gas purifying apparatus for internal combustion engine

The combustion air-fuel ratio is made leaner than the stoichiometric air-fuel ratio at the time of engine startup and the combustion air-fuel ratio is made richer than the stoichiometric air-fuel ratio and the exhaust downstream part of the three-way catalyst apparatus is raised in temperature when it is judged that just the exhaust upstream part of the three-way catalyst apparatus arranged in the engine exhaust system has been raised to the catalyst activation temperature.

Air-fuel ratio control device of internal combustion engine

An exhaust gas-purifying catalyst system is provided with a plurality of catalyst layers including a first and a second catalyst layers, supported on a support structure. The first catalyst layer comes into contact with an exhaust gas stream firstly among the plurality of catalyst layers. The second catalyst layer is provided adjacent to the first catalyst layer. The first catalyst layer contains a first noble metal active component including rhodium, together with a powder of a barely soluble barium compound in an amount of 0.05 mol to 0.2 mol per volume in liter of the support structure. The second catalyst layer contains a second noble metal active component.

Exhaust gas-purifying catalyst system

Growing community of inventors

Kakegawa, Japan

Masaaki Kawai