Enhanced Thermal Oxidation Stability of Jet Fuel by Deoxygenation Treatment

Thermal oxidation stability is an important parameter for jet fuel practical application. In this work, in order to evaluate the influence of deoxygenation on fuel stability, samples of typical fuels (JP-10 and RP-3) were subjected to deoxygenation by nitrogen purge and then subjected to accelerated thermal oxidation (180°C, 200°C, and 220°C). The parameters of hydroperoxide number, total acid number, size distribution of insoluble oxidation products, and concentration of remaining antioxidant (butylated hydroxytoluene, MIT) were monitored and analyzed. The results show that deoxygenation and thermal oxidation have very little influence on the fuel physical properties (density, net heating value, and kinematic viscosity). However, deoxygenation significantly reduces hydroperoxide number, total acid number, and remaining BHT concentration in the fuel after accelerated oxidation. Moreover, the deoxygenation treatment also inhibits the formation of soluble macromolecular oxidatively reactive species (SMORS) and insoluble oxidation products such as gums and deposits.