Cataler Corporation

Toyota Jidosha Kabushiki Kaisha

Shunsuke Oishi

Takaya Ota

Ryosuke Takasu

Hiromasa Suzuki

Yoshinori Saito

Isao Chinzei

Seiji Nakahigashi

Ryota Onoe

Keiichi Narita

Tatsuya Ohashi

Hirotaka Ori

Mitsuyoshi Okada

Ryota Nakashima

Ryo Tasaki

Takahiro Nagata

Hiromi Togashi

Minoru Itou

Shogo Kawamura

Taku Miura

Koki Aono

An exhaust gas purifying catalyst includes a base material and a catalyst layer. A first catalyst region including the catalyst layer formed therein is provided on an entry side surface of a partition wall of the base material. A second catalyst region including the catalyst layer formed on a wall surface of a pore is provided in a prescribed region from an exit side surface of the partition wall toward an entry side cell. A catalyst unformed region in which a catalyst layer is substantially not formed is provided between the first and second catalyst regions in the thickness direction Y of the partition wall. Thus, it is possible to prevent the deposition of PMs in the second catalyst region including the catalyst layer formed in the pore, and to establish the compatibility between the noxious gas purifying performance and the pressure loss suppressing performance at a high level.

Exhaust gas purification catalyst

In accordance with the technology herein disclosed, an exhaust gas purification catalyst exhibiting a high exhaust gas purifying performance using a new rare earth-containing material is provided. The exhaust gas purification catalyst herein disclosed includes a base material and a catalyst layer formed on the surface of the base material. The catalyst layer of such an exhaust gas purification catalyst includes rare earth-carrying alumina 50 including a primary particle of a rare earth particle 40 including at least one rare earth element carried on the surface of an alumina carrier 30 including alumina, and the average particle diameter Dbased on TEM observation of the rare earth particle 40 in the rare earth-carrying alumina 50 is 10 nm or less. As a result of this, it is possible to provide an exhaust gas purification catalyst having high NOx adsorption performance and CO adsorption performance.

An exhaust gas purification catalyst showing resistance to peeling and high purification performance is provided. The present invention is an exhaust gas purification catalyst including a base material and a catalyst layer disposed on the base material. The catalyst layer includes a catalytic metal, a first metal oxide, and a second metal oxide having a higher heat resistance than that of the first metal oxide. When Dx is an area-based average particle diameter of the first metal oxide determined from an arbitrary cross section of the catalyst layer and Dy is an area-based particle diameter of the second metal oxide 22 measured from the cross section of the catalyst layer, a ratio of the Dy to the Dx (Dy/Dx) is 5 or more, and the Dy is 7 μm or more. In the catalyst layer, pore volume of pores having pore diameters 30 nm or more measured by a nitrogen adsorption method is 0.28 cm/g or more.

The present invention provides an exhaust gas purification catalyst including a base materialand a catalyst layerprovided on the base material. The catalyst layerincludes: a catalyst metal; and a carrying materialcarrying the catalyst metal. The carrying materialincludes: an OSC materialhaving an oxygen storage capacity; and a carrierother than the OSC material. The OSC materialhas a mean particle diameter Dx of 1.5 μm or more which is larger than the mean particle diameter Dy of the carrierother than the OSC material

Methods for exhaust gas purification, including the steps of: attaching an exhaust gas purification catalyst to an exhaust system of an internal combustion engine, and supplying an exhaust gas to the exhaust gas purification catalyst, where the exhaust gas purification catalyst includes an upper layer containing first carrier particles which are particles of an inorganic oxide and rhodium, and a lower layer containing second carrier particles which are particles of an inorganic oxide, the upper layer includes a rhodium-rich portion near the surface of the upper layer on the upstream side of the exhaust gas flow, and the existence range of the rhodium-rich portion is in a range of greater than 50% to 80% of the length of the upper layer from a downstream side end of an exhaust gas flow and of less than 20 &#x3bc;m in the depth direction from an outermost surface of the upper layer.

Methods for exhaust gas purification

The exhaust gas purification catalyst device includes an upper layer which includes first carrier particles and rhodium, and a lower layer which includes second carrier particles, and the upper layer includes a rhodium enriched area in the range a, from the upstream end in the exhaust gas flow to 50% of the upper layer length, and a range b from the upper layer top surface to 18 &#x3bc;m in the depth direction. The rhodium enriched area contains at least 50% and less than 100% of all the rhodium in the upper layer.

Exhaust gas purification catalyst device

The present invention provides an exhaust gas purification catalyst including an alkaline earth metal supported in a highly dispersed state on a porous carrier. A catalyst layer of the exhaust gas purification catalyst provided by the invention has an alkaline earth metal-supporting region including a porous carrier, a catalyst metal belonging to the platinum group, and a sulfate of at least one type of alkali earth metal supported on the porous carrier. In a cross-section of this region, a Pearson correlation coefficient Ris at least 0.5 as calculated using &#x3b1; and &#x3b2; for each pixel obtained by carrying out area analysis by FE-EPMA under conditions of pixel size of 0.34 &#x3bc;m&#xd7;0.34 &#x3bc;m, and measured pixel number 256&#xd7;256, and by measuring the characteristic X-ray intensity (&#x3b1;:cps) of the alkaline earth metal element (Ae) and the characteristic X-ray intensity (&#x3b2;:cps) of the main constituent element of the inorganic compound constituting the porous carrier for each pixel.

An exhaust gas purification catalyst, excellent in the NOx purification capacity and the HC purification capacity, includes a substrate and a catalyst coating layer formed on the surface of the substrate, wherein the catalyst coating layer comprises the upper and lower layer including a lower layer being closer to the surface of the substrate and an upper layer being relatively remote from the surface of the substrate. The upper layer of the catalyst coating layer includes Rh, Pd, and a carrier. The lower layer of the catalyst coating layer includes at least one noble metal selected from Pd and Pt and a carrier. 65% by mass or more of Pd in the upper layer exists in a layer up to 50% of the upper layer in a thickness direction from the surface of the upper layer being relatively remote from the surface of the substrate. The ratio of Pd to Rh by mass (Pd/Rh) is 0.5 to 7.0 in the upper layer.

Growing community of inventors

Kakegawa, Japan

Shunsuke Oishi