Gas Chromatographic Measurement of Trace Oxygen and Other Dissolved Gases in Thermally Stressed Jet Fuel

摘要

A major factor that impacts jet fuel thermal stability is the concentration of dissolved oxygen. Present and future experimental fuel-stressing systems require the use of sensitive in-line analytical instrumentation for measuring trace levels of oxygen, methane, nitrogen, and so forth. Consequently, a dedicated in-line gas chromatographic (CC) system that utilizes a three-member tandem separation column arrangement is developed. With the use of this closed-loop continuous CC system, analyte separation, detection, and fuel backflush are accomplished rapidly. Detection capabilities for the various analytes are less than 50 ppb (w/w). Thermally stressed fuels in continuous flowing high-pressure streams are sampled every 15 min, thereby allowing frequent monitoring of changes in the fuel's dissolved gas portion. Examples of CC output data obtained from engineering simulation assemblies are presented, and possible expanded uses of the dedicated chromatographic system for fuel research are discussed.