Significant reduction of carbon deposit by hydrogen donor addition to JP-8 Jet Fuel at high temperatures

A study was carried out to further understand the role of hydrogen donors on the formation of solid carbons during thermal stressing of jet fuel through examination of the morphology and reactivity of the deposits from JP-8 stressed with the addition of various concentrations of tetralin and a binary donor of tetralin and α-tetralone. Addition of only 2 vol % tetralin to JP-8 jet fuel showed a significant reduction in carbon deposit accumulation on the surface by over 81% when compared to JP-8 without any additives. The carbon deposition that resulted from pyrolytic stressing of JP-8 with tetralin addition was mainly amorphous carbon with little presence of filamentous carbon and sulfide formation. Tetralin helped prevent bulk deposits and stabilize the organic sulfur compounds present in JP-8. By the reduction of sulfide formation, amorphous and filamentous carbon formations were significantly reduced. The addition of up to 5 vol % of a binary donor led to a lower degree of reduction in amorphous carbon. Sulfide formation was also significant from the decomposition of organic sulfur compounds in the JP-8 even with binary donor additions. The decomposition of the sulfur compounds present in the JP-8 fuel led to the formation of amorphous and filamentous carbon growth. The filaments present on the surface with the addition of the binary donor were longer and thinner than the filaments observed with JP-8 only. The binary donor reduced the levels of polyaromatics and bulk deposits, thus the metal sites that were active for the growth of filaments remained active.