Patent · US Expired

Zeolite-containing oxidation catalyst and method of use

US6248684A · kind A · utility

67Cited by
76References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 7, 1994
Grant dateJun 19, 2001
Priority date
Expiry dateJun 7, 2014

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02A50/20
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

Oxidation catalyst compositions for treating diesel exhaust include ceria and, optionally, alumina, each having a surface area of at least about 10 m.sup.2 /g, and a zeolite, e.g., Beta zeolite. Optionally, platinum may be included in the catalytic material, preferably in amounts which are sufficient to promote some gas-phase oxidation of carbon monoxide ("CO") and hydrocarbons ("HC") but which are limited to preclude excessive oxidation of SO.sub.2 to SO.sub.3. Alternatively, palladium in any desired amount may be included in the catalytic material. The zeolite is optionally doped, e.g., ion-exchanged, with one or more of hydrogen, a platinum group metal or other catalytic metals. The catalyst compositions may be used in a method to treat diesel engine exhaust by contacting the hot exhaust with the catalyst composition to promote the oxidation of gas-phase CO and HC and of the volatile organic fraction component of particulates in the exhaust.

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