Comprehensive Two-Dimensional Supercritical Fluid and Gas Chromatography with Independent Fast Programmed Heating of the Gas Chromatographic Column

With comprehensive two-dimensional supercritical fluid and fast, independent temperature-programmed gas chromatography (SFCxGC), a polar column was used in the first dimension to achieve group-type analysis. The eluent of this separation was repetitively sampled and transferred to a fast, resistively heated gas chromatograph to obtain the boiling point distribution over the entire polarity separation. The SFC was operated isothermally with stopped flow to provide a sufficient time span for the GC analysis. The GC analysis had a typical cycle time of 1 min for the system demonstrated here. During this time, the GC column was independently heated at a rate of 450 degrees C/min to 250 degrees C and actively cooled again to -50 degrees C before the next GC injection took place. The analysis of petrochemical samples is presented to illustrate the technique.