A method for the analysis of ppb level volatile sulfur compounds in a variety of hydrocarbons using a 6890N gas chromatograph equipped with dual flame photometric detectors is described. Thick film DB-1 and GS-GasPro columns are employed, and enhanced performance flame photometric detectors are used that can achieve detection of sulfur compounds below 20 ppb. Examples of arsine and phosphine analysis with the same hardware are also discussed.
This document describes a dual-channel gas chromatographic system utilizing an Agilent 6890N equipped with dual flame photometric detectors (FPD) for the analysis of ppb-level volatile sulfur compounds in hydrocarbon gases. The system employs two different separation columns, DB-1 and GS-GasPro, to avoid hydrocarbon interference and achieve detection limits below 20 ppb.
The text details the experimental setup, including recommended column combinations for various applications such as natural gas, fuel cell gases, and propylene. It provides specific gas flow settings for the FPDs when analyzing sulfur, arsine, and phosphine, and discusses the use of specialized inert sample introduction systems to prevent adsorption of organosulfur compounds.
| Detection Limit | below 20 ppb |
|---|---|
| Detector Type | flame photometric detectors |
| Oven Program (Natural Gas) | 40 °C (5 min) to 290 °C (5 min) |
| Oven Program (Propylene) | 35 °C (7 min) to 290 °C (5 min) |
The enhanced performance flame photometric detectors can achieve detection of sulfur compounds below 20 ppb.
The system uses a 60 m x 530 µm x 5.0 µm DB-1 column and a 30 m x 320 µm GS-GasPro column.
For sulfur analysis, the settings are Air 60 mL/min, Hydrogen 50 mL/min, and Makeup 58 mL/min.