Thermal Stability Enhancement of JP-5

The objective of this work was to determine if C60 or its derivatives could enhance the oxidative thermal stability of JP-5 and similar aviation fuels. Two derivatives of C60 were prepared, n-hexyl amine and di-isopropylamine. Several conventional thermal stressing experiments were also performed: oxygen overpressure (OOP), isothermal corrosion oxidation test (ICOT), quartz crystal microbalance (QCM), and hot liquid process simulator (HLPS). In addition, a fuel stability test system (FSTS) developed at Advanced Fuel Research, Inc. (AFR) was also used. The FSTS includes fiber optic infrared transmission cells to assess fuel thermal stability during thermal stressing up to 500 deg C. The low temperature data from OOP, ICOT, QCM and HPLS show that pure C60 generally reduces the deposit formation, although the amount of this reduction is only modest (between 5 and 30%). The beneficial effects are larger under more severe conditions (higher temperatures, longer oxidation times, higher oxygen concentrations). The FSTS results were consistent with this trend, although at the highest temperatures (425-500 deg C), some potentially deleterious effects of C60 also appear to be enhanced. The effects of reactor tube activation were important for the FSTS. Additional work is warranted on exploring the beneficial effects of C60 addition which could serve to extent the operating range of common jet fuels.