A strategy for enhancing ignition of aviation fuels at high altitudes using nanoparticle and fuel-soluble catalysts

Improving the ignition performance of aviation fuels in high-altitude environments is essential for the reliable operation of aero-engines. This study investigated the catalytic ignition of RP-3 aviation fuel at high-altitudes using Co 3 O 4 nanoparticles and fuel-soluble catalysts (platinum and palladium acetylacetonates). Ignition delay times (IDT) and ignition probabilities (IP) were measured in situ using thermocouples and a spectrometer. The results demonstrated that the addition of 150 ppm Co 3 O 4 nanoparticles exhibited the best catalytic performance, achieving 100% IP with the shortest average IDT of 1.41 s. In contrast, the IP of RP-3 without catalysts was only 25%, with an average IDT above 15.92 s. The fuel-soluble catalysts also significantly improved the ignition performance. With 150 ppm addition, both cases reached 100% IP but longer IDTs than that of Co 3 O 4 . Thermogravimetric analysis indicated that Co 3 O 4 nanoparticles catalyzed ignition through the Mars-van Krevelen mechanism at lower temperatures, while at higher temperatures they decomposed into CoO and O 2 , further facilitating ignition through both catalytic effect and the increased amount of oxidant. On the other hand, the fuel-soluble catalysts decomposed into noble metals or their oxidants that provided active sites for the surface oxidation of the fuel, with the heat release from this process initiating gas-phase ignition. These results provide a new strategy for ignition enhancement of aviation fuels in extreme environments via catalytic combustion.