Aviation fuel grades

Corrosion Inhibitor - helps prevent rusting of metal engine components. Also, corrosion inhibitors provide a protective film on metal surfaces to aid in improving the lubricating properties of jet fuel. Use is not permitted in aviation gasoline and civil jet fuels, but is mandatory in military jet fuel grades. 

Jet Fuels (Grades JP-3, JP-4, JP-S JP-6). Specifications for early aircraft jet fuels were based primarily on manufg considerations, since it was believed that aircraft could burn almost anything of the nature of kerosene fuels (Ref 1). Later improvements in aircraft, particularly in high-speed jets, made it necessary to pay more attention to fuel characteristics and less attn to ease of manuf. The most important of these fuel characteristics is fuel stability at high temps. Other problems associated with jet aviation fuels, both for military civilian use, are minor compared to stability at high temps. Such problems include availability, handling physical property specifications... 

In the event of another major war, it is probable that all existing isomerization units would be reactivated and pushed to capacity. Although production of Grade 115/145 aviation fuel required by newer aircraft engines may place somewhat greater emphasis on aromatics, there would still be a demand for maximum alkylate production, and butane isomerization would again play an important role. Expansion of pentane and naphtha isomerization is somewhat less certain and would depend on future developments in aircraft fuels. 

Only a limited number of additives are permitted in aviation fuels, and for each fuel grade the type and concentration are closely controlled by the appropriate fuel specifications. Additives may be included for a variety of reasons, but in every case the specifications define the requirements as follows ... 

The depot receives fuels via three pipelines from refineries located in different parts of Britain. At the time of the incident an aggregate total of 189,000 British tons (212,000 US tons) of aviation fuel, diesel, gasoline, and 15,000 British tons (16,800 US tons) of heating oil in the tankage were stored in the Buncefield storage tanks. Pipehnes transport fuel in batches and various grades of fuel were separated into dedicated tanks according to fuel type [ 1 ]. 

Evaporative processes are very important in the weathering of volatile petroleum products and may be the dominant weathering process for gasoline. Automotive gasoline, aviation gasoline, and some grades of jet fuel (e.g., JP-4) contain 20 to 99% highly volatile constituents (i.e., constituents with fewer than nine carbon atoms). 

US Specification MIL-T-5624J, Turbine Fuel, Aviation, Grades JP-4 JP-5 (Oct 1973)... 

Cowan, M.J., and L.J. Jenkins. 1981b. The Toxicity of Grade JP-5 Aviation Turbine Fuel, A Comparison Between Petroleum and Shale-Derived Fuels. Pp. B2/1-B2/7 in Toxic Hazards in Aviation. Papers presented at the Aerospace Medical Panel Specialists Meeting, Toronto, Canada, Sept. 15-19 1980. AGARD-CP-309, France Advisory Group for Aerospace Research Development. 

Military Specification, Turbine Fuel, Aviation Grades, JP-4 and JP-5, MIL-T-5624L, 18 May 1979. 

The reactor effluent goes to a settler, in which hydrocarbons separate from the acid. The acid is returned to the reactor. The hydrocarbons are washed with caustic and sent to fractionation. The fractionation section comprises a depropanizer, a deisobutanizer, and a debutanizer. Alkylate from the deisobutanizer can go directly to motor-fuel blending, or it can be reprocessed to produce aviation-grade gasoline. Isobutane is recycled. 

Table 30 shows specifications for five grades of jet fuel, otherwise known as aviation turbine fuel. The JP fuels are for military aircraft. 

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