FACTORS AFFECTING DUAL CATALYST SYSTEM PERFORMANCE

Results of warm-up and fuel economy studies on a dual catalyst system using GEM reinforced Ni-Cu nitrogen oxide reduction catalysts and PTX-II B oxidation catalysts are reported. Rapid warm-up of this system is required to control emissions to the target level of 3.4 g/mi. CO, 0.41 g/mi. HC, and 0.4 g/mi. nitrogen oxide. This rapid warm-up can be obtained only by oxidizing the CO, HC, and hydrogen in the exhaust during the first 30-60 seconds after start-up. Methods of inducing oxidation are described. Controlling nitrogen oxide to 0.4 g/mi. requires GEM catalyst temperatures of approximately 1300 deg F, which is 200 to 300 deg hotter than exhaust temperature during warmed-up operation. The additional temperature can be generated by enriching carburetion and oxidizing the CO, hydrogen, and HC formed, or by spark retard.

  • Corporate Authors:

    Society of Automotive Engineers

    485 Lexington Avenue
    New York, NY  USA  10017
  • Authors:
    • Lang, R J
    • Leppard, W R
    • Bernstein, H S
  • Publication Date: 1974-2

Media Info

  • Pagination: 12 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00264228
  • Record Type: Publication
  • Report/Paper Numbers: SAE Paper No. 740252
  • Files: TRIS
  • Created Date: Jan 9 1975 12:00AM