TREA

EXHAUST GAS PURIFICATION CATALYST

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Information

  • Patent Application
  • 20230294078
  • Publication Number
    20230294078
  • Date Filed
    March 02, 2023
    a year ago
  • Date Published
    September 21, 2023
    7 months ago
Information
Abstract
Provided is an exhaust gas purification catalyst improved in warm-up performance while suppressing HC poisoning of a noble metal in an atmosphere in which an air-fuel ratio (A/F) is rich and the HC poisoning easily occurs. The present disclosure relates to an exhaust gas purification catalyst that includes a substrate and a catalyst coating layer coated on the substrate. The catalyst coating layer includes a lower coating layer coated on the substrate and an upper coating layer coated on the lower coating layer. The lower coating layer contains a noble metal. The upper coating layer contains Pd and/or Pt. The Pd and/or Pt contained in the upper coating layer is supported on A12O3 by a certain amount or more. A thickness of the upper coating layer is adjusted.
Description
Claims
  • 1. An exhaust gas purification catalyst comprising: a substrate; anda catalyst coating layer coated on the substrate,wherein the catalyst coating layer comprises a lower coating layer coated on the substrate and an upper coating layer coated on the lower coating layer,wherein the lower coating layer contains a noble metal,wherein the upper coating layer contains Pd and/or Pt,wherein the Pd and/or Pt contained in the upper coating layer is supported on Al2O3 by 80 weight% or more of a total weight of the Pd and/or Pt contained in the upper coating layer, andwherein a ratio of a thickness of the upper coating layer to a thickness of the lower coating layer (upper coating layer/lower coating layer) is 0.2 or less.
  • 2. The exhaust gas purification catalyst according to claim 1, wherein the Pd and/or Pt contained in the upper coating layer is supported on Al2O3 by 90 weight% or more of the total weight.
  • 3. The exhaust gas purification catalyst according to claim 1, wherein the Pd and/or Pt contained in the upper coating layer is supported on Al2O3 by 95 weight% or more of the total weight.
  • 4. The exhaust gas purification catalyst according to claim 1, wherein the thickness of the upper coating layer is 20 µm or less.
Priority Claims (1)
Number Date Country Kind
2022-040137 Mar 2022 JP national