Vapor/Solid Chemisorption Model for Passive Sampling of Aldehydes

Details

• Personal Author:
  Que Hee SS ; Tsai S-W
• Description:
  The vapor-phase chemisorption isotherms of valeraldehyde (n-valeraldehyde; 1-pentanal) and acrolein (2-propenal) above the critical face velocity (7.5 cm/s) were investigated at 25 degrees C and 36 percent relative humidity (RH) for a passive air sampling pellet of 10 percent O-(2,3,4,5,6-pentafluorobenzyl)-hydroxylamine hydrochloride (PFBHA) on Tenax TA solid sorbent (80/100 mesh). A dynamic air dilution system with syringe pumps generated the vapor concentrations and humidity for the exposure chamber. The O-oxime derivatives were desorbed with hexane for gas chromatographic analysis on a nonpolar capillary column and electron capture detection. The pellet capacity was about 30 micromoles. Adsorption of valeraldehyde was best fitted by a Langmuir or Brunauer-Emmett-Teller (BET) I model. That for acrolein was described best by a Dubinin-Radushkevich model. A microporosity model explained why all the classical isotherms described the chemisorption behavior. An activated extrinsic precursor was suggested to facilitate the addition reaction by production of a protonated intermediate formed by the transfer of a proton to the aldehyde from an activated reaction site consisting of at least 2 PFBHA molecules. [Description provided by NIOSH]
• Subjects:
  Aldehydes Environmental Monitoring Formaldehyde Mass Spectrometry Occupational Health Safety Workplace
• Keywords:
  Air-sampling Air-sampling-techniques Exposure-limits Gas-chromatography Mass-spectrometry Sampling-methods Workplace-monitoring
• ISSN:
  1047-322X
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  California ; OSHA Region 9
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  17
• Issue:
  8
• NIOSHTIC Number:
  nn:20029609
• Citation:
  Appl Occup Environ Hyg 2002 Aug; 17(8):551-560
• Contact Point Address:
  Department of Environmental Health Sciences, UCLA Center for Occupational and Environmental Health, UCLA School of Public Health, Los Angeles, California
• CAS Registry Number:
  Acrolein (CAS RN 107-02-8) ; Hexane (CAS RN 110-54-3) ; Hydroxyamine hydrochloride (CAS RN 5470-11-1)
• Federal Fiscal Year:
  2002
• NORA Priority Area:
  Research Tools and Approaches: Exposure Assessment Methods
• Performing Organization:
  University of California Los Angeles, Los Angeles, CA
• Peer Reviewed:
  True
• Start Date:
  19950901
• Source Full Name:
  Applied Occupational and Environmental Hygiene
• End Date:
  19990831
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:2a3227307874b2e6eec69fc4b0fb0321c9bf6f76ddc25c5a4030c4d5d4db29ebb270cf92594a33960eac195dbba1e0f5e4b7228ea8f672ef0123242a18f2cb41
• Download URL:
  https://stacks.cdc.gov/view/cdc/190552/cdc_190552_DS1.pdf
• File Type:
  [PDF - 380.49 KB ]