Advanced Thermally Stable Coal-Based Jet Fuels

A successful pilot-plant campaign produced 100 barrels of prototype JP-900 coal-based jet fueL Most of this fuel was used by Williams International in a long test of their FJ44-3 aviation gas turbine engine. Results of this test program were that coal-based JP-900 is essentially a drop-in replacement for Jet A, except that the higher volumetric energy density of JP-900 would give the aircraft extended range, LaboratOl),- scale combustion tests showed that JP-900 produced a lower soot volume fraction than JP-8. This fuel, with an added cetane enhancer, was also successfully tested in over-the-road tests in a diesel-engine pickup truck. Blending studies of JP-900 with surrogate paraffinic fuels showed no incompatibility issues in terms of blend properties or stability. In most cases the blend properties were linear averages of the neat components. Continued laboratory-scale development of solvent extraction processing of coal showed that Pittsburgh seam bituminous coal provided 50% conversion to desired feedstock for processing into JP-900. Fuel stability studies showed correlations among the soluble macromolecular oxidatively reactive species, extraction-induced precipitates, and smoke point.