EVALUATION OF THREE-WAY CATALYSTS, PART II

A number of recent 3-way catalyst formulations were evaluated. A comparison was made of the effects of contaminant levels on the performance of pulsator - and dynamometer-aged selected catalysts. The problems of increased ammonia formation on pulsator - and dynamometer-aged catalysts which contain base-metal oxides as oxygen-storage or water-gas shift components is attributed to S-poisoning. An inverse relationship between ammonia formation and the amount of rhodium on aged 3-way catalysts was noted. The effects of deliberate misfire on the selectively and activity characteristics are discussed. Further, the role of the water-gas shift and steam-reforming components in extending the "window" was studied. The effect of temperature and of inlet CO (H2) and hydro-carbon concentration of these reactions was investigated separately on single component samples and fully formulated catalysts. The extent of sulfate formation over typical fresh and dynamometer-aged 3-way catelysts is shown. /GMRL/

• Corporate Authors:

  Society of Automotive Engineers (SAE)

  400 Commonwealth Drive
  Warrendale, PA  United States  15096
• Authors:
  • Gandhi, H S
  • Piken, A G
• Publication Date: 1977

Media Info

• Pagination: 42 p.

Subject/Index Terms

• TRT Terms: Base metal; Catalysts; Contaminants; Dynamometers; Hydrocarbons; Oxides; Sulfates; Temperature
• Uncontrolled Terms: Activity
• Old TRIS Terms: Pulsator; Selectivity
• Subject Areas: Highways; Safety and Human Factors;

Filing Info

• Accession Number: 00158384
• Record Type: Publication
• Report/Paper Numbers: SAE 770196
• Files: TRIS
• Created Date: Nov 23 1977 12:00AM