An exhaust gas purification catalyst having an excellent exhaust gas purification ability while reducing the increase in pressure loss. Exhaust gas purification catalyst includes entrance cell, exit cell, and a wall-flow substrate having partition wall to separate these cell, a catalytic layer formed from exhaust inlet-side ends in the extending direction in sections of the interior of partition wall facing entrance cell, and a catalytic layer formed on the surface of partition wall facing exit cell from exhaust outlet-side ends in the extending direction of partition wall, having a length shorter than the entire partition wall length.

An object of the present invention is to provide an exhaust gas purification catalyst for purifying exhaust gas, in particular, fine composite-metal particles contained therein, and a method for producing the same; the exhaust gas purification catalyst according to the present invention includes fine composite-metal particles containing Rh and Pd, wherein, when the fine composite-metal particles in the exhaust gas purification catalyst are analyzed by STEM-EDX, the average ratio of the amount of Pd with respect to the total amount of Rh and Pd in the fine composite-metal particles is 1.7 atomic % or more and 24.8 atomic % or less.

Provided is an exhaust gas purification catalyst in which the performance of a catalyst metal can be brought out properly, the purification catalyst boasting excellent purification performance during warm-up of an internal combustion engine. The exhaust gas purification catalyst 10 is provided with a substrate 1 and a catalyst layer. A leading end section 1a positioned upstream in the direction of exhaust gas flow (arrow) has a portion in which the flow rate of exhaust gas is relatively high and a portion in which the flow rate of exhaust gas is relatively low during warm-up of the internal combustion engine. The catalyst, layer in the portion of relatively high flow rate of exhaust gas has a high density section 6 in which a noble metal, is supported at relatively high density. The high density section 6 is formed to be shorter than the total length of the exhaust gas purification catalyst 10 from the leading end section 1a in the direction of exhaust gas flow.

An exhaust gas purification device of the present invention is provided with: a substrate of wall flow structure having an inlet cell, an outlet cell and a porous partition wall; an upstream catalyst layer, provided inside the partition wall and disposed in an upstream portion of the substrate including an exhaust gas inflow end section; and a downstream catalyst layer, provided inside the partition wall and disposed in a downstream portion of the substrate including an exhaust gas outflow end section. The upstream catalyst layer and the downstream catalyst layer each contain a carrier and at least one noble metal from among Pt, Pd and Rh, supported on the carrier. The noble metal in the upstream catalyst layer and the noble metal in the downstream catalyst layer are different from each other.

A catalytic converter with excellent OSC performance and No.sub.x purification performance. The catalytic converter includes a substrate with a cell structure and a catalyst layer formed on a cell wall surface of the substrate. The catalyst layer has a catalyst layer arranged on the upstream side and a catalyst layer arranged on the downstream side in an exhaust gas flow direction on the substrate. The catalyst layer on the upstream side includes a support containing an Al.sub.2O.sub.3—CeO.sub.2—ZrO.sub.2 ternary composite oxide (ACZ material) and an Al.sub.2O.sub.3—ZrO.sub.2 binary composite oxide (AZ material), and at least Rh that is a noble metal catalyst carried on the support, and the catalyst layer on the downstream side includes a support and Pd or Pt that is a noble metal catalyst carried on the support. In the support in the catalyst layer on the upstream side, the mass proportion of ACZ material/(ACZ material+AZ material) is in the range of 0.33 to 0.5, and greater than or equal to 75% mass Rh is carried on the Al.sub.2O.sub.3—ZrO.sub.2 binary composite oxide of the support.

An exhaust gas-purifying catalyst of the present invention comprises a substrate, and one or more catalytic layers provided on the substrate, wherein at least one of the catalytic layers (i) contains a precious metal, alumina, and an acidic oxide element, (ii) has a correlation coefficient ρ.sub.Al,AE of 0.70 or more, and (iii) has a correlation coefficient ρ.sub.PM,AE of 0.70 or more.

A catalysed filter for a positive ignition internal combustion engine comprises a porous filtering substrate having a total substrate length coated with a three-way catalyst washcoat composition comprising at least one precious metal selected from the group consisting of rhodium and one or both of platinum and palladium supported on a high surface area oxide, and an oxygen storage component, which composition being axially shared by a first zone comprising inlet surfaces of a first substrate length<total substrate length and a second zone comprising outlet surfaces of a second substrate length<total substrate length, wherein a sum of the substrate length in the first zone and the substrate length in the second zone≧100% and wherein one or both of the following applies: a washcoat loading in the first zone>second zone; and a total precious metal loading in the first zone>second zone.

The present invention relates to a method for producing a multilayer catalyst, to the multilayer catalyst produced by the method, and to the use of the catalyst for after-treatment of exhaust gases.

Provided is a powder inorganic oxide containing Al, Ce and Zr as constituent elements, that affords a molded product with a density of 1.0 to 1.3 g/ml by placing 4.0 g of the inorganic oxide in a cylindrical container having diameter 20 mm and performing uniaxial molding under conditions of room temperature and pressure of 29.4 MPa for 30 sec., and achieves an average shrinkage percentage of not more than 14.0% as calculated by the following formula: average shrinkage percentage (%)=100×{(1−(c)/(a))+(1−(d)/(b))}/2 wherein each symbol is as defined in the DESCRIPTION.

A device for converting harmful waste products into environmentally friendly discharge is provided. The discharge, as a result of the waste destruction process, meets or exceeds the Environmental Protection Agency (EPA) standards. The device includes a waste disposal chamber where a crucible is positioned. The crucible is configured to retain a removable basket that is heated via induction heating. The waste residing within the removable basket is then vaporized and ionized within a vacuum to form a waste gas that is drawn through an accelerated jet of thermal plasma via vacuum suction. Once the waste gas passes through the plasma, it passes through a discharge duct where it is condensed by a heat exchanger and exhausted into the environment surrounding the device.