Simulated Distillation and Molecular Weight Determination by Supercritical Fluid Chromatography
نویسنده
چکیده
Supercritical fluid chromatography (SFC) has recently become a popular technique for the analysis of crude oils. It has been demonstrated for simulated distillation (1) and for hydrocarbon type separation (2-3). The advantages of SFC over gas chromatography (GC) in simulated distillation are the wider boiling range and lower temperature thus preventing cracking of heavy molecules during analysis. Previous work with GC (4) has shown that average molecular weight can be determined for aromatic fractions using a technique similar to simulated distillation. The present study on retention time behaviour of standard compounds shows how the same approach can be applied to SFC. Correlations between retention times and boiling point, molecular weight and melting point have been studied.
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