In aviation gasoline

During World War II, isopropyl benzene, more commonly and commercially known as cumene, was manufactured in large volumes for use in aviation gasoline. The combination of a benzene ring and an iso-paraffin structure made for a very high octane number at a relatively cheap cost. After the war, the primary interest in cumene was to manufacture cumene hydroperoxide. This compound was used in small amounts as a catalyst in an early process of polymerizing butadiene with styrene to make synthetic rubber. Only by accident did someone discover that mild treating of cumene hydroperoxide with phosphoric acid resulted in the formation of... 

Gums which form in aviation gasoline could produce undesirable deposits on induction manifolds, carburetors, valves, injectors, etc. Strict limitations exist for the gum content of aviation gasoline. 

Antioxidants - prevent gum formation in fuel. The approved additives are generally phenolic based. Use is mandatory in aviation gasoline. Antioxidants are permitted in civil and military jet fuels. Antioxidants are mandatory in hydroprocessed British and U.S. military jet fuels as well as in international civil Jet A-l. 

Metal Deactivator - chelates metal ions, primarily copper. Copper catalyzes the oxidation and degradation of jet fuel. Use is not permitted in aviation gasoline. A metal deactivator is permitted in civil and military jet fuels. 

Anti-Static Additive - dissipates static charge in jet fuel. Static charge buildup can result in unwanted ignition of jet fuel/air mixtures. Use is normally not permitted in aviation gasoline except in Canada and Britain. Use is permitted in civil jet fuel and mandatory in military jet fuel. 

Lubricity Additive - used to help prevent wear of high-pressure fuel injection equipment. Use is not permitted in aviation gasoline and can be used only by permission in civil jet fuel. Use is mandatory in military jet fuel grades. Topically, the corrosion inhibitor also functions in providing adequate fuel lubricity performance. 

Although being regulated out of use due to its toxicity and exhaust emission contribution, alkyl leads and other organometallics are still used in some parts of the world to improve automotive gasoline antiknock performance. Alkyl lead is also used in aviation gasoline. 

In aviation gasoline, the value of tetraethyllead is still greater, as it would be practically impossible to manufacture aviation gasoline of the desired quality in quantity great enough to meet the demand, were it not for the use of an antiknock agent. 

Following the cessation of hostilities of World War II, there was a short period of abundant supply of aromatics, particularly toluene, caused by the sudden decline in consumption of aromatics for nitration and for use in aviation gasoline. Soon, however, the peacetime uses for aromatics created a demand which could be satisfied only by the combined production of aromatics from petroleum and coal-tar sources. Consequently, many of the toluene plants were purchased from the Government by the petroleum refiners and utilized for manufacture of the many aromatic products available on the market today. 

The major uses of mixed xylene are in aviation gasoline and protective coatings, and as a solvent for alkyd resins, lacquers, enamels and rubber cements. wetrr-Xylene is used as a solvent, as an intermediate for dyes and organic synthesis, especially isophthalic acid and insecticides, and in aviation fuel or// o-xylene is used in manufacture of phthalic anhydride, vitamin and pharmaceutical synthesis, dyes, insecticides, motor fuels para-xylene is used in synthesis of terephthalic acid for polyester resins and fibres, vitamin and pharmaceutical syntheses, and insecticides (Lewis, 1993). 

Ogilivie et al(Ref 4) found that bromopicrin, choloropicrin, Br other compds caused an increase in the knocking tendency in aviation gasoline. These compds counteracted the effect of antiknock additives also had some effect on the base stock fuel... 

Pentadecylbenzene, made by the alkylation of benzene with pentamer, is coming into demand because of the higher detergency of the sulfonate, as compared with dodecylbenzene sulfonate. c. Cumene. Cumene was formerly used as an additive in aviation gasoline... 

Use Antioxidant for petroleum products, jet fiiels, rubber, plastics, and food products, food packaging, animal feeds. Satisfies ASTM D910-64T for use in aviation gasoline. 

Use Intermediate, antioxidant, satisfies ASTM D910-64T for use as antioxidant in aviation gasoline. 

It has to be noted, that aviation gasoline is required to be an all hydrocarbon product. Its components must be chemicals that contain only carbon and hydrogen atoms. The use of oxygenated or other oxygen containing compounds, such as alcohols or ethers, is not allowed. Only a few select additives are permitted and their use is strictly controlled and limited. The primary ingredient in aviation gasoline is isooctane. 

Oxygenates tetraethyl- and tetramethyl-lead are no longer used as additives to improve octane ratings, except in aviation gasoline. Today, ethers such as methyl tertiary butyl ether (MTBE), produced by conversion of olefins with methanol, are used to improve octane rating. 

Pb(C2H5)4 is subject to oxidation in gasoline in the presence of air, with the consequent formation of haze or precipitates [14, 16, 64]. It exerts an influence on gum formation in gasolines, mainly in aviation gasolines, with the result that leaded gasolines are somewhat less stable than unleaded fuels in normal storage [16, 64]. 

ASTM standardization of methods for hydrocarbon analysis started in 1942 when Committee D02, Technical Division on Gasoline, established a subgroup to standardize a procedure for the determination of aromatics in gasolines for use by the military. This method was first issued in March of 1943 as Emergency Standard ES 45, Test for Olefins, Aromatics, Paraffins, and Naphthenes in Aviation Gasoline (Without Distillation Into Fractions). This method was a combination of several procedures, some of which are still commonly used. 

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