This document introduces the technology for analyzing trace compounds in ethylene using the Agilent 7890A GC, including methods for analyzing trace oxygenates and hydrocarbons.
The document details a method for analyzing trace contaminants, specifically oxygenates and hydrocarbons, in ethylene feedstocks. It highlights that traditional methods like ASTM D6159 are time-consuming because they require separate instruments for different compound classes.
The Agilent 7890A GC is presented as the ideal platform to perform this analysis in a single run using Capillary Flow Technology and 2-D Deans switch chromatography. The text explains how this setup protects sensitive alumina PLOT columns from polar oxygenates while allowing for the automated preparation of multilevel calibration standards.
| Primary Column | HP-INNOWax, 30 m x 0.32 mm id x 0.5 pm film |
|---|---|
| Secondary Column | Alumina HP-PLOT M, 30 m x 0.53 mm id x 15 pm |
| Primary Column Flow | Helium at 2.6 mL/min |
| Secondary Column Flow | Helium at 6 mL/min |
| Oven Temperature Program | 40 °C for 6 min, 4 °C/min to 125 °C |
It allows for the simultaneous analysis of trace oxygenates and hydrocarbons in a single run using 2-D GC Deans switching, whereas the original method requires separate instruments.
A wax-type liquid phase (HP-INNOWax) placed before the alumina column retains polar compounds, preventing them from entering the sensitive alumina PLOT column.
Yes, expanded capabilities in auxiliary EPC channels allow for the automated preparation of ppmV gas standards for trace level impurities.