Capillary supercritical fluid chromatography

dc.contributor.authorHensley, Jack Leeen
dc.contributor.committeechairMcNair, Harold M.en
dc.contributor.committeememberBell, Harold M.en
dc.contributor.committeememberTaylor, Larry T.en
dc.contributor.committeememberMason, John G.en
dc.contributor.committeememberWightman, James P.en
dc.contributor.departmentChemistryen
dc.date.accessioned2015-06-24T13:35:23Zen
dc.date.available2015-06-24T13:35:23Zen
dc.date.issued1986en
dc.description.abstractThe modification of a gas chromatograph for capillary supercritical fluid was demonstrated. The resulting instrument was used to characterize the performance of capillary columns manufactured specifically for SFC applications. The columns were tested for inertness, efficiency, and immobilization before and after extraction with the supercritical CO₂ solvent. Stable deactivation layers were obtained with polyethylene glycol pyrolysis of Carbowax 20M and Superox 20M. Crosslinking was evaluated with dicumyl peroxide (DCP) and azo-t-butane (ATB) as free radical initiators with OV-1701 as a stationary phase. ATB was found to yield more efficient crosslinking and had less effect on column polarity. Quantitative reproducibility of SFC was evaluated for alkanes, alcohols and acids on columns which were deactivated by polyethylene glycol pyrolysis or by mixed cyclic siloxanes. Both gave better reproducibility than an untreated column but the overall reproducibility of the polyglycol deactivation was better than the cyclic deactivation. Liquid CO₂ extraction was performed on a variety of spices and food products. This sample preparation proved useful in isolating CO₂ soluble materials from complex matrices which were insoluble in CO₂.en
dc.description.degreePh. D.en
dc.format.extentx, 210 leavesen
dc.format.mimetypeapplication/pdfen
dc.identifier.urihttp://hdl.handle.net/10919/53623en
dc.language.isoen_USen
dc.publisherVirginia Polytechnic Institute and State Universityen
dc.relation.isformatofOCLC# 15994237en
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V856 1986.H47en
dc.subject.lcshFluidsen
dc.subject.lcshChromatographic analysisen
dc.titleCapillary supercritical fluid chromatographyen
dc.typeDissertationen
dc.type.dcmitypeTexten
thesis.degree.disciplineChemistryen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.leveldoctoralen
thesis.degree.namePh. D.en

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
LD5655.V856_1986.H47.pdf
Size:
5.16 MB
Format:
Adobe Portable Document Format