MAKING CLEAN GASOLINE THE EFFECT ON JET FUELS.

Abstract : Persistently high concentrations of carbon monoxide and low-altitude ozone in the air of the Nation's major urban centers led Congress in the 1990 Clean Air Act Amendments to mandate changes to the composition of gasoline and diesel fuel. Those gasoline composition changes will require major modifications to the manufacturing processes that refiners use to produce gasoline for sale in much of the United States. Since petroleum refining is a complex process involving a variety of chemical interactions between final products, many observers - including DoD fuel managers - fear possible declines in the quality and availability of jet fuel. Currently, the Air Force plans to convert from naphtha-based JP-4 jet fuel to distillate-based JP-8 jet fuel. Despite the extent of the required refinery process modifications, however, we conclude that neither the quality nor the availability of jet fuel purchased by the military is likely to change significantly. Among the provisions of the 1990 Clean Air Act Amendments is a limit on aromatic compounds in gasoline, which led to fears that refiners would divert excess aromatic compounds into jet fuel. However, refiners are unlikely to do that for two reasons. First, existing jet fuel specification - 'smoke point' and a maximum aromatic ceiling - already limit the refiners' ability to increase the volume of aromatics in jet fuel. Second, the manufacture of aromatics to improve gasoline performance is expensive.