Pyrolysis Coupled with Capillary Supercritical Fluid Chromatography

Abstract

Pyrolysis coupled with gas chromatography and carbon dioxide supercritical fluid extraction/supercritical fluid chromatography was used to study the affect of pyrolysis temperature (500 or 999°C) and pyrolysis atmosphere (helium or carbon dioxide) on the resulting chromatographic profiles of asphaltenes. The use of the lower pyrolysis temperature yielded fewer and less volatile components than did the high pyrolysis temperature. This was supported by both gas chromatographic profiles and the profiles obtained after supercritical fluid extraction and chromatography. Fast atom bombardment/Mass spectrometry (FAB/MS) and Fourier Transform Infrared Spectrophotometric (FTIR) studies revealed, for these experiments, that although the pyrolysis process greatly altered the structure of the asphaltenes, the effect of the atmosphere present during pyrolysis appeared to have little affect on the fragments formed when these reactions were carried out at ambient pressure.