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SummaryWith the simultaneous development of blank aluminum clad flexible fused silica glass capillary tubing capable of withstanding temperatures up to 5OO0C, coincident with a series of special high temperature methyl polysiloxane polymers, it was possible to produce for the first time, long lived fused silica capillary columns containing thin films of thermostable stationary phases which could be maintained isothermally at 400-425OC and temperature programmed to 425-440OC. The "bleed rate" here for a well conditioned column was 5 picoamperes or less. Under these circumstances, alkanes with carbon numbers in theC-90 toC-l00area wererapidlyand efficientlyeluted from these columns. By extrapolation here, one can easily detect certain compounds with boiling points in the 75OOC range. Since this type of capillary column was found to possess certain favorable properties, it was thought that it will soon replace the packed column and will probably be more popular than the borosilicate capillary column for many high temperature applications. Moreover, evidence has now accumulated which leads us to further believe that the majority of analyses of "high molecular weight" compounds performed by Supercritical Fluid Chromatography (SFC), utilizing very narrow bore fused silica capillary columns at several hundred atmospheres, can be much more simply, much more rapidly, much more economically, and much more efficiently accomplished by gas chromatography utilizing this new generation of high temperature capillary columns.

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The pulsed flame photometric detector (PFPD) has the advantage of being able to measure the concentration of individual sulfur compounds and total sulfur content in a petrochemical sample in a single gas chromatography run. Because it is an equimolar response detector, the PFPD's sulfur response is independent of a compound's molecular structure, and this feature allows quantitation of the total or speciated sulfur content in complex samples using a single calibrant. This paper is a survey describing a variety of applications using the PFPD for sulfur quantitation in petrochemical matrices. Several different approaches to quantitation are described, and simple techniques for circumventing the quenching of the sulfur signal by coeluting hydrocarbon peaks are discussed. Examples from a range of real-world samples are presented.