Abstract
Different types of deposit regularly observed during "specification" JFTOT testing were simulated. The most significant deposition occurred in the presence of 2-methylindole at 270° and 280°C. A slight increase occurred for thianaphthene, but this was only slightly outside the experimental errors involved in with the method. In contrast to Jet A-1 fuel (J1), in dodecane, little deposition occurred up to 340°C with the same range of compounds. The additional component(s) in J1 were present in a limiting concentration, since the deposit volume data reached a plateau level with increasing addition of 2-methylindole. In view of the known chemistry of jet fuels, these observations led to a study on the possibility that metal ions could contribute to the deposition process, which confirmed that little deposition occurred ≤ 340°C. However, in the presence of CuII and 2-methylindole, significant deposits were produced on Al tubes, which bore a strong resemblance to those generated from J1 in the presence of 2-methylindole. At the highest CuII concentration tested, an intense "peacock" coloration was produced.