This article introduces the method of optimizing determination of C1-C6 impurities in propylene and ethylene using HP-PLOT/Al2O3 columns. Compared with other commercially available alumina PLOT columns, HP-PLOT columns have better selectivity, increased capacity and complete baseline separation. HP-PLOT column analyses were done using the 5890 Series II gas chromatograph with electronic pressure control and a flame ionization detector.
This document details the analysis of trace impurities in high-purity hydrocarbon gases, specifically propylene and ethylene. It compares the performance of Agilent HP-PLOT/Al2O3 columns against other commercially available alumina PLOT columns, such as Alumina/KCl and Brand X columns. The study highlights that HP-PLOT columns offer better selectivity, increased sample capacity, and complete baseline separation for critical impurities like cyclopropane, acetylene, and isobutane, which often suffer from masking or co-elution on other columns.
| Gas Chromatograph Model | 5890 Series II with EPC |
|---|
HP-PLOT columns provide better selectivity and complete baseline separation, whereas Alumina/KCl columns often fail to separate critical impurities like cyclopropane from propylene.
For the quantitation of acetylene, the retention index (RI) should be greater than 400 to prevent coelution with isobutane.