Fuel octane enhancer

Some isopentane is dehydrogenated to isoamylene and converted, by processes analogous to those which produce methyl /-butyl ether [1634-04-4] (MTBE) to /-amyl methyl ether [994-05-8] (TAME), which is used as a fuel octane enhancer like MTBE. The amount of TAME which the market can absorb depends mostly on its price relative to MTBE, ethyl /-butyl ether [637-92-3] (ETBE), and ethanol, the other important oxygenated fuel additives. 

MTBE is an organic compound, mainly used for replacing lead as a car fuel octane enhancer. Additionally, MTBE is an oxygenate added to car fuel to improve the combustion efficiency of gasoline. Other oxygenates are ethers... 

A. Jonqui6res, R. Cldment, and P. Lochon. New film-forming poly(ureth-ane-amide-imide) block copolymers influence of soft block on membrane properties for the purification of a fuel octane enhancer by pervaporation. Eur. Polym. J., 41(4) 783-795, April 2005. 

A recently marketed fuel additive is MMT (methyl cyclopentadienylmanganese tricarbonyl). MMT was first developed by the Ethyl Corporation in 1957 as an octane enhancing agent and has experienced a growth in demand in the 1990s. MMT was Ethyl Corporation s first major new antiknock compound since TEL. 

In the 1990s the U.S. methanol industry was producing almost 4 million gallons of methanol per day. Only a third of this was used as fuel for transportation and much of it was converted to MTBE. Methanol is also popular in high-performance racing because of its octane-enhancing qualities. 

Leaded fuels are now banned across Canada. In unleaded gasoline, simple organic compounds are added instead of lead compounds. These octane-enhancing compounds include methyl-t-butyl ether, t-butyl alcohol, methanol, and ethanol. Like lead catalysts. 

The major uses of isobutylene are estimated in Table 8.5. Much of isobutylene is a captive market used by refineries in alkylation or polymerization of gasoline. The remainder goes into the octane enhancer MTBE, polyisobutylene, and butyl rubber. Some is burned for fuel. 

Table 8.9 shows the non-fuel uses of toluene. Some of the toluene goes into gasoline depending on its supply and price compared to other octane enhancers. Of the other uses of toluene about half is converted into benzene by hydrodealkylation, though this amount varies with the price difference between benzene and toluene. 2,4-Toluene diisocyanate (TDI) is a monomer for polyurethanes. Included in miscellaneous uses is 2,4,6-trinitrotoluene (TNT) as an explosive. 

Hakki A. Tellis C. in "Octane enhancers for motor-fuels AICHE Meeting ref. 3 paper nr. 78d. 

Much recent attention and investigation has been focused on the use of ethanol as a gasoline extender, octane enhancer, or as an alternative fuel. Many studies have been performed to evaluate the engine performance, emission characteristics, and the advantages and problem areas encountered in conventional spark... 

The first octane enhancers were lead compounds such as tetraethyl lead (TEL) or tetramethyl lead (TAIL). A few milligrams of either converted inexpensive, low-octane gasoline into high-test fuels. As the danger of lead to... 

Branched hydrocarbons are preferred to linear hydrocarbons as ingredients in petrol because they enhance the fuel octane number. By catalytic isomerisation linear hydrocarbons are converted into mono and di branched hydrocarbons, and it becomes necessaiy to separate the mixture. A variety of zeolites may be used for this purpose, either on the basis of sorption thermodynamics or on the basis of sorption kinetics. Such data are relevant to the development of sorption based separation methods, but also they provide key information regarding the catalytic isomerisation over zeolites themselves. 

Commercial production of methyl -butyl ether began in 1979, shortly after the discovery of its octane-improving capability for motor fuels. Although a higher proportion of this additive was required for equivalent octane enhancement, it was less costly and eliminated the lead particulate discharges associated with the tetraethyl lead previously used (Chap. 18). By 1984 it ranked 49th in American volume of production and jumped to 12th by 1995, an... 

Fuel Science and Technology Handbook, edited by James G. Speight Octane-Enhancing Zeolitic FCC Catalysts,... 

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