APPLICATION OF JFA-5 AS AN ANTIFOULING ADDITIVE IN A JET-A FUEL

A commercial Jet-A aviation fuel, POSF-2827, was treated with an antif ouling additive package, DuPont Jet Fuel Additive No. 5 (JFA-5), at a concentration of 12 mg/L. Fouling of heated stainless-steel (304) tube s from the neat and treated fuels was studied over the temperature ran ge 155-390 degrees C using a single-pass heat exchanger and at 185 deg rees C in flask tests. The rate of autoxidation in the treated fuel wa s slowed over the temperature range 1.55-225 degrees C, but total surf ace fouling evaluated after 100% conversion of dissolved oxygen was no t reduced. Significant reduction (factor of 2-3) in surface fouling wa s observed at the higher temperatures, 255 and 300 degrees C. This imp rovement was traced to one component of the package, namely, a metal d eactivator present at 2 mg/L. Additive packages such as JFA-5 which co ntain antioxidant, dispersant, and-in particular-metal-deactivator com ponents may reduce Jet-A fuel fouling in certain temperature regimes.