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Gasoline antiknocking agents

Alkyl lead compounds are extremely effective gasoline antiknock agents. By decomposing to form lead oxide compounds during the gasoline combustion process, lead alkyls interrupt the rapid chain scission reactions which lead to combustion knock. Also, lead alkyls help to prevent exhaust valve seat wear and may minimize octane requirement increase. However, unless utilized in conjunction with lead scavengers such as 1,2-dichloromethane, lead deposits can accumulate within the gasoline combustion chamber. [Pg.120]

Industrial uses of sodium are based primarily on its strong reducing properties. A large part of the annual sodium production is needed to produce the gasoline antiknock agents tetramethyllead and tetraethyllead. It is also employed for the reduction of titanium and zirconium chlorides to produce titanium and zirconium metals. The remaining part of sodium is used to produce compounds such as sodium hydride, sodium alkoxides, and sodium peroxide. Sodium is also used, especially in alloys with potassium, as a heat exchange liquid in fast-breeder nuclear reactors. [Pg.572]

Gasoline is a mixture of different compounds. A typical blend contains nearly 200 different hydrocarbons and additives such as antioxidants and antiknock agents. Thirteen of the chemicals commonly found in gasoline (nine hydrocarbons and four additives) are regulated as hazardous substances under CERCLA. Table 18.1 lists the chemicals along with the values of toxicity, water solubility, vapor pressure, and biodegradability.19... [Pg.702]

Tetraethyllead was used in the past as an antiknock agent in gasoline, but it has been phased out in most countries. Alkyllead compounds have a detergent-like activity on liposomes and black lipid membranes [232], Tributyllead destroys planar lipid membranes at lower concentrations than tripropyllead, which is again more effective than triethyl- and trimethyllead [232]. Inorganic lead compounds like lead acetate and lead nitrate were effective only at twice as high concentrations [232]. [Pg.248]

It is a common phenomenon to find that apparently innocuous species that do not participate in catalytic reactions can strongly poison or inhibit catalytic reactions. As examples, sulfur compounds are severe poisons for most catalysts, and the lead formerly added to gasoline as an antiknock agent completely kills the catalyst by covering its surface sites. [Pg.305]

Another limitation on the use of catalytic oxidation is the susceptibility of the catalysts to various deactivators or poisons, although according to the vendor the phase out of the use of volatile lead alkyls as antiknock agents in U.S. gasoline, catalyst poisoning is today rarely encountered. [Pg.734]

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. [Pg.234]

Antiknocks. Antiknock agents are used to improve the natural knock resistance of gasolines used in Otto-cycle gasoline engines, knock being the power-robbing, po-... [Pg.237]

Discuss the historical aspects of organometallic compound toxicity, including organoarsenicals used as pharmaceutical agents, gasoline antiknock additives, and compounds used in applications such as catalysis and chemical synthesis. [Pg.286]

The only commercial competition for tetraethyllead as an antiknock agent is provided by tetramethyllead and mixed methyl and ethyl lead compounds. In 1960, Ethyl Corporation and E. I. DuPont de Nemours and Company inaugurated the manufacture of tetramethyllead in the U.S.A., and in the same year Mobil Oil Company and Standard of California began the marketing of gasoline containing tetramethyllead. Various mixed methylethyllead compounds and mixtures have been patented and have been supplied commercially since this period 65,113,129),... [Pg.54]

Methyl t-Butyl Ether (MTBE). In 1980, MTBE was the fastest-growing derivative of methanol. This is a result of its only significant use, which is as an antiknock agent replacing lead in gasoline. In 1990, it was the fastest-growing chemical in the world. The world production has reached 48 billion in 1999. The U.S. production was about 30 billion lb, which was 63 percent of world capacity. [Pg.350]

The organic chemistry of lead has had significant economic importance. For example, tetraethyllead was formerly used as an antiknock agent in gasoline to the extent of about 250,000 tons annually. Organic compounds of lead can be prepared by reactions such as the following ... [Pg.270]

The use of cyclopentadienyl-carbon monoxide compounds of Mn, as anti-knock agents in fuels, has been known for some time. In recent years the use of methylcyclopentadienyl manganese tricarbonyl (MMT) as an antiknock agent for gasoline has become more widespread, due to the decline in use of Pb alkyl compounds. [Pg.302]

The use of methylcyclopentadienylmanganese tricarbonyl and related compounds as antiknock agents in gasoline 18j 19, 39),... [Pg.525]

Methyl r-butyl ether (CHjOQCHj),) 52 A new solvent that is very inexpensive because of its large-scale industrial use as an antiknock agent in gasoline. Does not easily form peroxides. [Pg.29]

In the past, lead solder was used to seal canned foods and lead pipes were used to carry drinking water. Tetraethyl lead was once routinely added to gasoline as an antiknock agent certain vehicles may still use leaded gasoline (e.g., agricultural vehicles). Lead was commonly used in paint, with certain formulations containing up to 50% lead. [Pg.1516]


See other pages where Gasoline antiknocking agents is mentioned: [Pg.127]    [Pg.127]    [Pg.440]    [Pg.584]    [Pg.825]    [Pg.249]    [Pg.69]    [Pg.253]    [Pg.15]    [Pg.382]    [Pg.249]    [Pg.231]    [Pg.223]    [Pg.223]    [Pg.236]    [Pg.237]    [Pg.134]    [Pg.259]    [Pg.440]    [Pg.339]    [Pg.146]    [Pg.146]    [Pg.54]    [Pg.69]    [Pg.72]    [Pg.375]    [Pg.19]    [Pg.289]    [Pg.574]    [Pg.380]    [Pg.883]    [Pg.1219]    [Pg.220]    [Pg.91]    [Pg.597]   
See also in sourсe #XX -- [ Pg.964 ]

See also in sourсe #XX -- [ Pg.1048 ]




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