Fourier transform infrared spectrometric detection of chromatographic effluents: instrumental and methodological improvements using a flow cell interface

The Fourier Transform Infrared spectrometer (FTIR) has been used increasingly as a detector for various forms of chromatography. Clearly the most established marriage has been that of the Gas Chromatograph (GC) with the FTIR. GC-FTIR has been developed well beyond other forms. The main objective of this thesis, however, is to extend the FTIR as a detector to previously untested forms of chromatography using a flow cell interface. These forms of chromatography include High Performance Liquid Chromatography (HPLC), both normal-phase and reversed-phase, and packed-column Supercritical Fluid Chromatography (SFC). Normal phase HPLC-FTIR was demonstrated on not only analytical scale columns, but semi-preparative and microbore scales as well. Significant advantages, particularly with respect to the low solvent consumption, were found in the microbore HPLC-FTIR experiment. This led to the development of a chromatographically improved flow cell, the Zero Dead Volume (ZDV) HPLC-FTIR interface. The ZDV cell shows superior chromatographic characteristics and has unique spectrometric characteristics because of its unusual cross-section. Detection limits as low as 40 ng were observed. Extension to reversed-phase HPLC-FTIR required incorporation of the Flow Injection Analysis (FIA) technique of low-dispersion flowing extraction. The compounds separated by HPLC are extracted into an infrared-transparent solvent, and the extracted compounds are detected by similar means to normal-phase HPLC-FTIR. Investigation of SFC-FTIR incorporated a high-pressure, gold-lined lightpipe flow cell to detect the components separated by the supercritical C0₂/packed-column chromatograph. Several unusual spectrometric characteristics were noted. Detection limits as low as 50 ng were observed with SFC-FTIR.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Chemistry

Department dc:contributor.department

Chemistry

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1985

Author dc:creator

• Johnson, Charles Clifford

Chair dc:contributor.committeechair

• Taylor, Larry T.

Committee members dc:contributor.committeemember

• Dorn, Harry C.
• Bell, Harold M.
• Graybeal, Jack D.
• Dillard, John G.
• McNair, Harold M.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/54450

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/54450