Exploratory screening and development of potential jet fuel thermal stabilizers over 400 degrees Celsius

In modern jet aircraft the fuel has a secondary function and also acts as a coolant. Unless adequately stabilized, jet fuels degrade to produce carbonaceous deposits that are detrimental to aircraft performance. In aircraft flying at speeds greater than Mach 4 the fuel is expected to experience temperatures as high as 400-500{dollar}spcirc{dollar}C, where the cleavage of carbon-carbon bonds into free radicals is facile and leads to the rapid degradation of aliphatic hydrocarbons.; The formation of carbonaceous materials is significantly retarded in hydrocarbon mixtures containing hydrogen donors and the primary objective of this work was to screen and develop superior jet fuel thermal stabilizers. In the temperature range between 400 and 450{dollar}spcirc{dollar}C, 1,2,3,4-tetrahydroquinoline is by far the best thermal stabilizer discovered and significantly more effective than benzyl alcohol, the previous benchmark.; While 1,2,3,4-tetrahydroquinoline and benzyl alcohol are fine high temperature thermal stabilizers that efficiently inhibit the thermal degradation of dodecane, jet fuels and similar hydrocarbon mixtures, kinetic studies reveal that the rate of dodecane degradation in the mixtures is a very strong function of temperature above 400{dollar}spcirc{dollar}C. In fact, it will be extremely difficult to adequately stabilize hydrocarbon fuels using hydrogen donors at temperatures much above 500{dollar}spcirc{dollar}C.