Published:Journal of Chromatographic Science,
ISSN 0021-9665Volume
39, Number 12, December 2001, pp. 530-537
Calibration of an Optical Condensate Measurement Technique Using
Indirect Static Headspace Gas Chromatography
Paul B. Hoke, Paul R. Loconto,
and John J. McGrath Departments of Mechanical, Civil, and Environmental Engineering,
the Great Lakes and Mid-Atlantic Hazardous Substance Research Center, Michigan
State University, East Lansing, MI 48824
Researchers in the Department of Mechanical Engineering seek
to obtain a means to measure less than 3 mg of H2O that adheres to a metal surface
as condensate. The objective is to calibrate optical reflectance measurements
of an aluminum surface as a function of the condensate thickness present. Collaboration
with the Hazardous Substance Research Center at Michigan State University results
in the development of an indirect static headspace gas chromatographic technique
capable of measuring H2O in low-milligram quantities. The technique utilizes
manual headspace sampling, a megabore capillary column, and a flame ionization
detector. A correlation of r2 = 0.999 is obtained for the calibration of the
indirect measurement technique. The calibration of the analytical instrument
demonstrates adequate precision (< ± 50 µg at a 95% confidence
interval) for such a heterogeneous sample. The calibration samples consist of
a strip of aluminum metal, H2O, and pulverized calcium carbide to convert the
H2O to acetylene. A scaled calibration technique is used to simplify handling
trace water volumes. The surface reflectance measurements are found to correlate
well (r2 = 0.935) with measurements of the condensate mass. This result facilitates
the development of an optical mass- transfer measurement technique. This study
focuses on the analytical method and its relationship with engineering research.
Reproduction
of editorial content of this journal is prohibited without publisher’s
permission.
This
article is available in its entirety by fax for $4.00 per
page.
Visa or MasterCard accepted.
To
order electronicallyclick here or call: 847-647-2900 ext. 1323 or fax request to: 847-647-1155.
Please
indicate JCS volume and issue along with
page numbers.
