Toyota Jidosha Kabushiki Kaisha

Cataler Corporation

Kabushiki Kaisha Toyota Chuo Kenkyusho

Takeshi Nobukawa

Akira Morikawa

Akihiko Suda

Naoki Takahashi

Masao Watanabe

Oji Kuno

Kae Yamamura

Tomomasa Aikawa

Hiromasa Suzuki

Hiroshi Tanaka

Masahide Miura

Toshitaka Tanabe

Isao Chinzei

Yusuke Saito

Yuki Aoki

Hirotaka Ori

Makoto Tsuji

Nobuyuki Takagi

Akiya Chiba

Hiroto Imai

Mayuko Osaki

Isao Naito

Shigeharu Takagi

Hiroki Nihashi

Takahiro Hayashi

Kimitoshi Sato

Kae Konishi

Naoki Kumatani

Shogo Kawamura

Kazutoshi Akashi

Hiroto Yoshida

Yasuyoshi Sasaki

Kazunari Sawada

Ryuta Fujii

Keiji Horaguchi

An exhaust gas purification catalyst including an alkaline-earth metal carried on a porous carrier in a highly dispersed state. The catalyst layer of the exhaust gas purification catalyst has an alkaline-earth metal carrying region including a porous carrier, Pt, and a sulfuric acid salt of at least one alkaline-earth metal carried on the porous carrier, wherein a value of Ris 0.5 or more, where Rrepresents the Pearson's correlation coefficient calculated using &#x3b1; and &#x3b2; in each pixel obtained by, for a cross section of the region, performing the area analysis by FE-EPMA under the conditions of: pixel size 0.34 &#x3bc;m&#xd7;0.34 &#x3bc;m; and number of measured pixels 256&#xd7;256; and measuring an intensity (&#x3b1;: cps) of a characteristic X ray of an element (Ae) of the alkaline-earth metal and an intensity (&#x3b2;: cps) of a characteristic X ray of Pt for each pixel.

Exhaust gas purification catalyst

An apparatus for diagnosing deterioration of an NOx storage-reduction catalyst for purifying an exhaust gas discharged from an internal engine, including an intake air amount detection unit for detecting an intake air amount to the internal combustion engine, an exhaust gas temperature detection unit for detecting the temperature of an exhaust gas passing through the NOx storage-reduction catalyst, an NOx purification rate detection unit for detecting NOx in an exhaust gas flowing into the NOx storage-reduction catalyst and in an exhaust gas flowing out of the NOx storage-reduction catalyst, thereby detecting an NOx purification rate, and a diagnostic unit for, when the temperature of the exhaust gas passing through the NOx storage-reduction catalyst increases following an increase in the intake air flow rate to the internal combustion engine and in turn, the temperature of the NOx storage-reduction catalyst greatly increases over a first predetermined threshold value, calculating a difference in the NOx purification rate between before and after the rise of temperature of the NOx storage-reduction catalyst, and diagnosing the NOx storage-reduction catalyst as being deteriorated when the NOx purification rate difference is larger than a second predetermined threshold value.

Apparatus for diagnosing deterioration of NOx storage-reduction catalyst

An object of the present disclosure is to provide an exhaust gas purification catalyst device; an exhaust gas purification system; and a method for detecting deterioration of the above device. The exhaust gas purification catalyst device includes a substrate, a first catalyst layer containing Pd and formed on the substrate, and a second catalyst layer formed on the first layer. Regarding the above device, ceria, Pd, and Rh are contained in a mixed state in the second layer; in the first and second layers, the total mass of ceria having a fluorite-type structure per 1 L volume of the substrate is 16.0 g or less; and in the second layer, the mass of Pd per 1 L volume of the substrate is 0.32 g or more.

Exhaust gas purification catalyst device, exhaust gas purification system, and method for detecting deterioration of exhaust gas purification catalyst device

Exhaust gas purification device having a catalyst layer including an Rh&#x2014;Ba-loaded catalyst, and a Pt/Pd&#x2014;Ba-loaded catalyst. The exhaust gas purification device satisfies at least one of (a) the degree of Rh&#x2014;Ba dispersion is greater than 0.001 and less than 1.000, (b) the loaded amount of Ba based on the weight of a first carrier particle in the Rh&#x2014;Ba-loaded catalyst is greater than 0.01% by weight and less than 10.00% by weight, and the loaded amount of Ba based on the weight of a second carrier particle in the Pt/Pd&#x2014;Ba-loaded catalyst is 10.00% by weight to 20.00% by weight, and (c) the loaded amount of Ba based on the weight of the first carrier particle in Rh&#x2014;Ba-loaded catalyst is greater than 0.005 times to less than 0.800 times the loaded amount of Ba based on the weight of the second carrier particle in Pt/Pd&#x2014;Ba-loaded catalyst.

Exhaust gas purification device

A catalyst system for exhaust gas purification which comprises a first-stage base metal catalyst located upstream and a second-stage base metal catalyst located downstream, wherein the first-stage base metal catalyst comprises at least one oxide support selected from the group consisting of alumina, ceria, zirconia, yttria, and titania and Cu metal and/or a Cu oxide supported thereon, and in cases where the amount of NOx in the exhaust gas has become or exceeded an NOx criterion, the state of the exhaust gas is switched from slightly rich to rich.

Catalyst system for exhaust gas purification utilizing base metals, and controlling method therefor

A catalyst support for purification of exhaust gas includes a porous composite metal oxide, the porous composite metal oxide containing alumina, ceria, and zirconia and having an alumina content ratio of from 5 to 80% by mass, wherein after calcination in the air at 1100&#xb0; C. for 5 hours, the porous composite metal oxide satisfies a condition such that standard deviations of content ratios (as at % unit) of aluminum, cerium and zirconium elements are each 19 or less with respect to 100 minute areas (with one minute area being 300 nm in length&#xd7;330 nm in width) of the porous composite metal oxide, the standard deviation being determined by energy dispersive X-ray spectroscopy using a scanning transmission electron microscope equipped with a spherical aberration corrector.

Catalyst support for purification of exhaust gas, catalyst for purification of exhaust gas using the same, and method for producing the catalyst support for purification of exhaust gas

A ceria-zirconia base composite oxide contains a composite oxide of ceria and zirconia. In the ceria-zirconia base composite oxide, a content ratio between cerium and zirconium in the composite oxide is in a range from 43:57 to 48:52 in terms of molar ratio ([cerium]:[zirconium]). An intensity ratio of a diffraction line at 2&#x3b8;=14.5&#xb0; to a diffraction line at 2&#x3b8;=29&#xb0; {I(14/29) value} and an intensity ratio of a diffraction line at 2&#x3b8;=28.5&#xb0; to the diffraction line at 2&#x3b8;=29&#xb0; {I(28/29) value}, which are calculated from an X-ray diffraction pattern obtained by an X-ray diffraction measurement using CuKa after heating under a temperature condition of 1100&#xb0; C. in air for 5 hours, respectively satisfy the following conditions: I(14/29) value&#x2267;0.015, and I(28/29) value&#x2266;0.08.

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

Provided is an exhaust purification system for an internal combustion engine. The exhaust purification system comprising: a NOpurifying catalyst arranged in an exhaust passage of the internal combustion engine, wherein the NOpurifying catalyst comprises a base metal supported on a catalyst support; an oxygen sensor arranged at the downstream side of the NOpurifying catalyst in the exhaust passage; and an air-fuel, ratio control means for controlling the air-fuel ratio of exhaust gas flowing into the NOpurifying catalyst; wherein when the NOpurifying catalyst suffers from predetermined oxygen poisoning, the air-fuel ratio control means controls the air-fuel ratio of the exhaust gas, which flows into the NOpurifying catalyst, to a first air-fuel ratio wherein the first air-fuel ratio is richer than a theoretical air-fuel ratio, and then the air-fuel ratio control means switches the air-fuel ratio of the exhaust gas, which flows into the NOpurifying catalyst, to a second air-fuel ratio on the basis of an output value from the oxygen sensor wherein the second air-fuel ratio is leaner than the first air-fuel ratio.

Exhaust purification system for internal combustion engine

An exhaust gas control apparatus for an internal combustion engine includes a NOx purification catalyst disposed in an exhaust passage of the internal combustion engine and carrying a first catalyst metal on a first catalyst carrier, an oxidation catalyst disposed in the downstream exhaust passage of the NOx purification catalyst and carrying second catalyst metals including a base metal on a second catalyst carrier, an air introduction apparatus introducing air into an upstream of the oxidation catalyst, and a temperature detector detecting a temperature of the oxidation catalyst. When an oxidation catalyst temperature is a predetermined temperature or lower, an air-fuel ratio of the exhaust gas into the oxidation catalyst is controlled to a more fuel lean ratio than the stoichiometric air-fuel ratio. When the oxidation catalyst temperature exceeds the predetermined temperature, the air-fuel ratio of the exhaust gas into the oxidation catalyst is controlled to the stoichiometric air-fuel ratio.

Exhaust gas control apparatus for internal combustion engine

The invention relates to an exhaust gas purification device of an internal combustion engine comprising a catalyst () having an active element and a composite oxidation which carries the active element in an exhaust passage (), the active element transforming into the composite oxide as a solid solution when the catalyst temperature is higher than or equal to a predetermined solid solution temperature and the atmosphere of the interior of the catalyst is an oxidation atmosphere and the active element precipitating from the composite oxide when the catalyst temperature is higher than or equal to a predetermined precipitation temperature and the atmosphere of the interior of the catalyst is a reduction atmosphere. According to the invention, in case that the performance of the fuel supply stop control is inhibited when the catalyst temperature is higher than or equal to the performance inhibiting temperature, a temperature lower than a base temperature of the performance inhibiting temperature is set as the performance inhibiting temperature while the use degree of the catalyst is lower than or equal to a predetermined degree and in case that the performance of the fuel supply amount increase control is permitted when the catalyst temperature is higher than or equal to a performance permitting temperature, a temperature higher than a base temperature of the performance permitting temperature is set as the performance permitting temperature while the use degree of the catalyst is smaller than or equal to the predetermined degree.

Exhaust gas purification device of internal combustion engine

An exhaust gas purification catalyst has a substrate, a lower catalyst layer that is formed on the substrate and contains at least one of Pd and Pt, and an upper catalyst layer that is formed on the lower catalyst layer and contains Rh. A region that does not contain the upper catalyst layer is disposed on the exhaust gas upstream side of this exhaust gas purification catalyst. The lower catalyst layer includes a front-stage lower catalyst layer on the exhaust gas upstream side and a rear-stage lower catalyst layer on the exhaust gas downstream side. The front-stage lower catalyst layer contains an oxygen storage material.

Double layered exhaust gas purification catalyst

An exhaust purifying catalyst includes: a substrate; a first-stage catalyst that includes an oxygen storage capacity (OSC) material and that is provided on the substrate on an upstream side thereof in an exhaust gas flow direction; and a second-stage catalyst that includes an OSC material and that is provided on the substrate on a downstream side thereof in an exhaust gas flow direction. The OSC material included in the first-stage catalyst and the second-stage catalyst includes OSC material on which a noble metal is not supported. The proportion of the amount of the OSC material, on which a noble metal is not supported, and that is included in the second-stage catalyst with respect to the combined amount of the OSC material, on which a noble metal is not supported, and that is included in the first-stage catalyst and the second-stage catalyst is in a range of from 0 to 50 wt %.

Exhaust purifying catalyst

An exhaust gas purifying catalyst that contains a first oxygen storage material on which no noble metal is supported and which has a pyrochlore phase type regular array structure, and a second oxygen storage material which has a higher oxygen storage rate and a lower oxygen storage capacity than the first oxygen storage material and on which a platinum group noble metal is supported.

Growing community of inventors

Toyota, Japan

Takeshi Nobukawa