Aromatics content aviation fuel

Petroleum and Petrochemical Processes. The first large-scale appHcation of extraction was the removal of aromatics from kerosene [8008-20-6J to improve its burning properties. Jet fuel kerosene and lubricating oil, which requite alow aromatics content (see Aviation and OTHER gas... 

Furthermore, the higher aromatics content and the possible presence of oxygenates in motor gasoline can induce solvent characteristics that are unsuitable for seals, gaskets, fuel lines, and some fuel tank materials in aircraft. Motor gasoline may also contain additives that could be incompatible with certain in-service aviation turbine fuel (ASTM D-4054, ASTM D-4307). For example, alcohols or other oxygenates can increase the tendency for the fuel to hold water, either in solution or in suspension. 

The aromatics content of aviation turbine fuel is included in the aviation turbine fuel specification (ASTM D-1655). Another test method for aromatics content (ASTM D-5186) involves the injection of a small aliquot of the fuel sample onto a packed silica adsorption column and elution with supercritical carbon dioxide as the mobile phase. Mono- and polynuclear aromatics in the sample are separated from nonaromatics and detected with a flame ionization detector. The chromatographic areas corresponding to the mono- and polynuclear and nonaromatic components are determined, and the mass percent content of each of these groups is calculated by area normalization. The results obtained by this method are at least statistically more precise than those obtained by other test methods (ASTM D-1319, ASTM D-2425). 

Kerosene (middle distillate) Paraffins. Chain length of Cjo to Cjg. Mixture of kerosene and gasoline fractions with an aromatic hydrocarbon content < 25%. For kerosene and aviation fuel. 120-200... 

The combustion quality of aviation turbine fuel has traditionally been controlled in specifications by such tests as smoke point, smoke volatility index, aromatic content of luminometei number. Evidence is accumulating that a better control of the quality may be obtained by limiting the minimum hydrogen content of the fuel. 

Determination of the Aromatic Content and Polynuclear Aromatic Content of Diesel Fuels and Aviation Turbine Fuels By Supercritical Fluid Chromatography ... 

Because the aromatic hydrocarbon content of aviation turbine fuels affects their combustion characteristics and smoke forming tendencies, the amounts of aromatics (ASTM D-1319, IP 156) are limited. Aromatic constituents also increase the luminosity of the combustion flame (ASTM D-1740), which can adversely affect the life of the combustion chamber. 

Dissolved water is also present in the fuel. The amount of water solubility in fuel is related to the hydroearbon ehain length, the presence of an aromatic structure, and temperature. Shorter chain paraffins dissolve more water than the longer chain paraffins. Kerosene fuels are more susceptible to microbial attack because they have a greater capacity to absorb dissolved water than other fuel types. There is 1 part per million (ppm) of dissolved water in aviation kerosene fuel for every degree Celsius (C) above zero (Park, 1975). An aromatie hydroearbon ean dissolve five times more water than straight chain hydrocarbons. Chemicals used to treat fuel such as preservatives can also contribute to the dissolved water content. 

This test method for naphthalene hydrocarbons is one of a group of tests used to assess the combustion characteristics of aviation turbine fuels of the kerosene boiling range. The naphthalene hydrocarbon content is determined because naphthalenes, when burned, tend to have a relatively larger contribution to a sooty flame, smoke, and thermd radiation than single ring aromatics. 

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