EVALUATION OF METHODS USED TO DESORB THE CONSTITUENTS ADSORBED ON THE CHARCOAL CONTAINED IN AUTOMOTIVE EVAPORATIVE CANISTERS. PART 2

The report presents the conclusion of a two-part study which evaluated current extraction methods for analyzing charcoal canisters used to control evaporative emissions in automobiles. The second part of the study investigated the use of solvent-free extraction methods such as high pressure CO2 soxhlet extraction and vacuum transfer extraction. The results of the solvent-free methods were then compared to the CS2 soxhlet extraction methods. The results of the study showed that the CS2 method extracted up to 8% more material (by weight) from the charcoal than did the vacuum transfer method and up to 15% more material (by weight) than did the high pressure CO2 soxhlet extraction method. In addition more total hydrocarbons were measured with the CS2 method than were measured in either the vacuum transfer or the high pressure CO2 methods. The high pressure CO2 soxhlet extraction method gave the lowest hydrocarbon measurements of the three methods.

• Supplemental Notes:
  • See also PB90-188830.
• Corporate Authors:

  Environmental Protection Agency

  Atmospheric Research and Exposure Assessment Laboratory
  Research Triangle Park, NC  United States  27709
• Authors:
  • Dropkin, D
• Publication Date: 1990-2

Media Info

• Pagination: 69 p.

Subject/Index Terms

• TRT Terms: Air quality management; Carbon dioxide; Chemical analysis; Evaporative emissions; Hydrocarbons; Resource extraction; Solvents; Tests
• Uncontrolled Terms: Extraction (Chemistry)
• Old TRIS Terms: Carbon disulfide; Evaporative emission control; Solvent extraction tests
• Subject Areas: Highways; Vehicles and Equipment; I91: Vehicle Design and Safety;

Filing Info

• Accession Number: 00497079
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: EPA/600/3-90/013B
• Files: TRIS
• Created Date: Sep 30 1990 12:00AM