Determination of phenolic antioxidants in aviation jet fuel

The world-wide aviation jet fuel used for civil and military aircraft is of a kerosene type. To avoid peroxide production after the refinery process a specific antioxidant additive should be added on fuel. The antioxidants generally used are based on hindered phenols in a range of concentration 10-20 microg/ml. In the present work a specific method to measure the concentration of phenolic antioxidants is shown. The method is based on a liquid chromatographic technique with electrochemical detection. The technique, because of its selectivity, does not require sample pre-treatments. The analysis of a 5-10 ml fuel sample can be performed in less than 10 min with a sensitivity of 0.1 microg/ml and a RSD=2.5%. A comparison with another highly selective gas chromatographic technique with mass spectrometric detection with selected ion monitoring (GC-MS-SIM) is reported. The sensitivity of GC-MS-SIM method was 2 microg/ml with a RSD=3.1%.