Water aviation fuel

Urea has the remarkable property of forming crystalline complexes or adducts with straight-chain organic compounds. These crystalline complexes consist of a hoUow channel, formed by the crystallized urea molecules, in which the hydrocarbon is completely occluded. Such compounds are known as clathrates. The type of hydrocarbon occluded, on the basis of its chain length, is determined by the temperature at which the clathrate is formed. This property of urea clathrates is widely used in the petroleum-refining industry for the production of jet aviation fuels (see Aviation and other gas-TURBINE fuels) and for dewaxing of lubricant oils (see also Petroleum, refinery processes). The clathrates are broken down by simply dissolving urea in water or in alcohol. 

The original intent of this specification was to prevent the addition of high-octane, water-soluble components such as alcohol or diisopropyl ether to aviation gasoline. Present specifications require fuel, water and interface ratings by ASTM D-1094. 

Alkanes undergo combustion reaction with oxygen at high temperatures to produce carbon dioxide and water. This is why alkanes are good fuels. Oxidation of saturated hydrocarbons is the basis for their use as energy sources for heat, e.g. natural gas, liquefied petroleum gas (LPG) and fuel oil, and for power, e.g. gasoline, diesel fuel and aviation fuel. 

The detection of water in some organic liquids is of considerable importance, e.g. both antifreeze (ethylene glycol) and aviation fuel (kerosene) should contain as little water as possible. Such materials can be monitored for water content by the use of non-dispersive infra-red techniques or turbidimeters (Section 6.8.1). 

War-time Germany was an empire built on coal, air and water. 84.5% of her aviation fuel, 85% of her motor fuel, more than 99%> of all her rubber, 100% of her concentrated nitric acid —the base substance for all military explosives — and 99%> of her no less important methanol were synthesized from these... 

The determination of hydroperoxide number is significant because of the adverse effect of hydroperoxides on certain elastomers in the fuel systems. This method (ASTM D-6447) measures the same peroxide species,primarily the hydroperoxides in aviation fuels. This test method does not use the ozone-depleting substance l,l,2-trichloro-l,2,2-trifluoroethane (ASTM D-3703) and is applicable to any water-insoluble, organic fluid, particularly diesel fuels, gasoline, and kerosene. In this method, a quantity of sample is contacted with aqueous potassium iodide (KI) solution in the presence of acid.The hydroperoxides present are reduced by potassium iodide,liberating an equivalent amount of iodine, which is quantified by voltametric analysis. 

Features Exc. resist, to aviation fuels, fresh and salt water, weathering, low temp, oxidation cured using inorg. peroxides, org. oxidizing agents, urethane or epoxy resins... 

FuelSTAT resinae was developed by Conidia Bioscience, Ltd. for the rapid (10 min) identification of Hormoconis resinae in aviation fuel. This is a semi-quantitative immunoassay test that will determine if the level of H. resinae contamination is below the level of significant contamination, per the lATA Microbial Contamination Task Force recommendations. This test has the sensitivity to determine the presence of 1,000 pg of H. resinae biomass in 1 liter of fuel or 1 ml of water. Test results of negative, low positive or high positive correlate to < 1000, 1,000 to 10,000 or > 10,000 pg of the fungus in either 1 liter of fuel or 1 ml of water respectively. The manufacturer of this test kit suggests that an aviation fuel system be monitored at least once a year. However, if the aircraft travels in warm, tropical areas it is advisable to monitor once a month. If the test indicates a low positive contamination, some action may be needed and monitoring should be done more often. With a high positive test result, immediate remedial action is required (Conidia Bioscience Ltd, 2002). 

A significant reason for the majority of oil and fuel system failurcs is the presence of high water levels as dissolved, dispersed, and free water, which degrades the fuels and oils. There are mainly four types of nonwoven filter media fiequently used for the removal of water contaminations contained in a wide range of fuel and oil products, such as aviation fuel, automotive diesel, and hydraulic oils. They include ceUulosic pulp filter, man-made fibre filter, glass fibre media, water adsorption (eg. 

When sampling aviation fuel. Practice D4306 diould be consulted for recommended cleaning procedures for containers that are to be used in tests for the determination of water separation, copper corrosion, dectrical conductivity, thermal stability, lubridty, and trace metal content. 

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