Aerosol nitrate and sulfate: Measurements by three different co-located samplers

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5015679

Johnson, S A; Kumar, R

Atmospheric aerosol samples were collected and analyzed at Argonne National Laboratory near Chicago, Illinois, at irregular times during the summer and fall of 1986. Three different sampling techniques were used: the /open quotes/Canadian Filter Pack/close quotes/ (CFP) collected aerosol particles and reactive gases on separate teflon membrane filters, the Annular Denuder System (ADS) removed the acidic and basic gases from the sampled air stream before the particles were collected on a teflon membrane filter; and the Attenuated Total internal Reflection (ATR) impactor collected size-fractionated submicrometer aerosol particles on KRS-5 internal reflection elements. The CFP and ADS collected 24-hour samples, while the ATR collected consecutive 4 or 6 hour samples. Particle samples collected by each of the three different techniques were analyzed for nitrate, sulfate, bisulfate, ammonium, and other ionic species by Fourier-transform infrared (FTIR) spectroscopy, either directly from the sample filters or from the internal reflection elements. Significant differences were observed in the nitrate content of the samples collected by the three different techniques. Further, the measured nitrate levels changed during storage. In many ATR samples the nitrate content decreased over a storage period of hours to weeks; in some cases the nitrate disappeared completely; some other samples showed a stable nitrate content after an initial decrease; and in at least one case, a high level of nitrate persisted over a long storage time. This /open quotes/volatile/close quotes/ nitrate was observed only in the ATR samples; samples from the CFP and ADS showed only the stable nitrate. 5 refs., 3 figs.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5015679
• Report Number(s): CONF-8806123-3; ON: DE88010046
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AEROSOLS
AIR SAMPLERS
AMMONIA
CHARGED PARTICLES
COLLOIDS
COMPARATIVE EVALUATIONS
DEPOSITION
DISPERSIONS
EQUIPMENT
HYDRIDES
HYDROGEN COMPOUNDS
INFRARED SPECTRA
IONS
NITRATES
NITROGEN COMPOUNDS
NITROGEN HYDRIDES
OXYGEN COMPOUNDS
SAMPLERS
SAMPLING
SOLS
SPECTRA
SULFATES
SULFUR COMPOUNDS