This document describes the method of analyzing the 370-550 °C petroleum fraction using the Agilent J&W FactorFour VF-5ht UltiMetal column. The column has high temperature and corrosion resistance, which can improve the signal-to-noise ratio and detection limits.
The document details the analysis of heavy hydrocarbon fractions (C20-C40) found in petroleum waxes and lube stocks. It recommends the on-column injection mode for this specific type of analysis due to the demanding conditions required.
The note provides specific chromatographic conditions for the analysis, including the use of a VF-5ht UltiMetal column (30 m x 0.25 mm, df=0.1 µm) with a hydrogen carrier gas. The temperature program starts at 40 °C and ramps to 400 °C, with peak identification provided for hydrocarbons ranging from C20 to C60.
| Column Length | 30 m |
|---|---|
| Column Inner Diameter | 0.25 mm |
| Film Thickness | 0.1 µm |
| Carrier Gas | Hydrogen |
| Injector Temperature | 325 °C |
| Detector Temperature | 340 °C |
| Temperature Program | 40 °C (0.5 min) to 400 °C |
| Ramp Rate | 5 °C/min |
On-column injection is the preferred mode for analyses of this type.
The analysis uses a Flame Ionization Detector (FID) set to 340 °C.