Polyaromatic compounds in heavy fractions characterized by capillary flow GCxGC FID
Résumé
Comprehensive two-dimensional GC is a powerful technique that can be used to separate very complex mixtures such as those found in the hydrocarbon processing, perfums, . Petroleum industry is an important application area for GCxGC. It is now routinely applied in R&D refining groups for the characterization of ligh fuels (gasoline, gas oil). In addition, flow modulation offers a viable alternative to thermal modulation without the burdens imposed by cryogenic requirements for comprehensive GCxGC. If cryogenic trapping is the reference technique for volatile and semi volatile compounds, it may be a drawback for heavy molecules such as polycyclic aromatic hydrocarbons on long chains alkanes which are difficult to volatilize after cryo trapping. We have enlarged the field of application of GC X GC using the differential flow modulator (DFM) to work on heavier feddstocks. The first results obtained were first under normal GC conditions were in good agreement with data coming from a cryogenic system. The differential flow modulator was installed on a GC FID 7890A Agilent for High Temperature GC. Acquisition and treatment of the detector signal were performed with the Agilent Chemstation, the data were transferred to GC-Image software (ZOEX) for data processing. The calibration of the system with paraffinic compounds demonstrates that paraffins up to C60 can be analyzed. Thus DFM GCxGC- FID technique was applied to the characterization of atmospheric residues, converted atmospheric residues or coal liquids. The GCxGC technique allowed discriminating between saturated and aromatic compounds with well identified families from mono- up to pentaromatic compounds.