Comprehensive two-dimensional supercritical fluid and gas chromatography (SFCxGC)

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dc.contributor.advisor Rohwer, Egmont Richard en
dc.contributor.postgraduate Venter, Andre en
dc.date.accessioned 2013-09-06T14:40:29Z
dc.date.available 2003-04-17 en
dc.date.available 2013-09-06T14:40:29Z
dc.date.created 2003-02-15 en
dc.date.issued 2004-04-17 en
dc.date.submitted 2003-03-13 en
dc.description Thesis (PhD)--University of Pretoria, 2004. en
dc.description.abstract A novel chromatographic method was devised that makes use of the superb group separation power of normal phase supercritical fluid chromatography (SFC) combined with a fast second separation by a resistively heated gas chromatograph (GC). The SFC was operated isothermally with stopped flow to provide the time required for the GC analysis. The GC analysis had a typical cycle time of 1 minute. During this time the GC column was independently heated at a rate of 450°C/min to 250°C and actively cooled down again to -50°C before the next GC injection takes place. This was achieved with an in-house designed, resistively heated, temperature programmable gas chromatograph. Various temperature measurement circuits were also evaluated. An interface was developed that allows transfer between the SFC and the GC in such a way that the entire eluent from the first separation is analysed by the second separator. Chromatographic resolution was not lost during the transfer process from the first to the second separation stages. The interface also allows for the exchange of the carrier gas used in the second gas chromatographic separation to provide for the maximum separation speed. In the first separation, a silica gel packed column and the novel application of a silica gel porous layer open tubular capillary column was used for SFC group separation. The SFCxGCftp was applied to petrochemical samples and essential oils and the results were compared to that obtained with a commercially available GCxGC system. en
dc.description.availability unrestricted en
dc.description.department Chemistry en
dc.identifier.citation Venter, A 2003, Comprehensive two-dimensional supercritical fluid and gas chromatography (SFCxGC), PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/23155 > en
dc.identifier.upetdurl http://upetd.up.ac.za/thesis/available/etd-03132003-161136/ en
dc.identifier.uri http://hdl.handle.net/2263/23155
dc.language.iso en
dc.publisher University of Pretoria en_ZA
dc.rights © 2003, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. en
dc.subject Sfcxgc en
dc.subject Modulation en
dc.subject Petrol analysis en
dc.subject Diesel analysis en
dc.subject Supercritical fluid chromatography en
dc.subject Fast temperature programmed gas chromatography en
dc.subject Multidimensional chromatography en
dc.subject Comprehensive chromatography en
dc.subject Sfc en
dc.subject Oxygenate analysis en
dc.subject Essential oil analysis en
dc.subject Modulator en
dc.subject Fuel analysis en
dc.subject UCTD en_US
dc.title Comprehensive two-dimensional supercritical fluid and gas chromatography (SFCxGC) en
dc.type Thesis en


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