Determination of jet fuel system icing inhibitor by GC×GC-FID

Abstract

Jet fuel usually contains a small amount of dissolved water, which can separate out at high altitudes and low temperatures. This can bring along serious clog issues as water can freeze in fuel pumps, lines, or filters; blocking the fuel flow which can even cause engine shut down. To prevent such a disaster, an additive called fuel system icing inhibitor (FSII) is added to jet fuels. The amount of FSII is regulated in both civil and military jet fuels by pertinent standards. A method for quantification of FSII: diethylene glycol monomethyl ether (DiEGME) by comprehensive two-dimensional gas chromatography with flame ionization detector (GC × GC-FID) was developed. The method allows the determination of DiEGME from a very small quantity of samples (0.5 μL) and is very fast with a mean absolute error of 0.001 vol% and a correlation coefficient of 0.9997. The DiEGME content (in the range of 0.07–0.12 vol%) in 23 fuel samples was analyzed via GC × GC-FID. The accuracy of the proposed method was evaluated by the ASTM standard D5006. The procedure that utilizes a refractometer, outlined in D5006, is currently the only available standard for determining the DiEGME concentration in fuel. Results were within the repeatability of the D5006 method (0.009 vol%). Since the D5006 method is accepted as an accurate technique for DiEGME content determination, the GC × GC method proposed in this study can be considered precise and accurate.