Patent · US Expired

Catalyst for purifying exhaust gases

US7737077B2 · kind B2 · utility

23Cited by
30References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 25, 2004
Grant dateJun 15, 2010
Priority date
Expiry dateJan 19, 2026

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/12
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

This is to provide a catalyst for purifying exhaust gases, catalyst which are good in terms of the purifying performance.A catalyst according to the present invention for purifying exhaust gases comprises: a catalytic support substrate (1); a first catalytic layer (2) having a first loading layer formed on an upstream side of the catalytic support substrate (1) and made of a fire-resistant inorganic oxide, and Rh loaded in the first loading layer; a second catalytic layer (3) having a second loading layer formed on a surface of the catalytic support substrate (1) on an downstream side of the first catalytic layer (2) and made of a fire-resistant inorganic oxide, and Pd and/or Pt loaded in the second loading layer; and a third catalytic layer (4) having a third loading layer formed on a surface of the second catalytic layer (3) and made of a fire-resistant inorganic oxide, and Rh loaded in the third loading layer; and is characterized in that: the first catalytic layer (2) is such that, when taking Rh loaded in the first catalytic layer as 100% by weight, Rh is loaded in an amount of 70% by weight or more within such a range that the distance from the surface is 20 μm; and the loadi…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.