Tertiary Butyl Ether

MTBE-ETBE (methyl- or ethyl-tertiary butyl ether)... 

Ecole Nationale Superieure du Petrole et des Moteurs Formation Industrie end point (or FBP - final boiling point) electrostatic precipitation ethyl tertiary butyl ether European Union extra-urban driving cycle volume fraction distilled at 70-100-180-210°C Fachausschuss Mineralol-und-Brennstoff-Normung fluid catalytic cracking Food and Drug Administration front end octane number fluorescent indicator adsorption flame ionization detector... 

Dehydrogenation of Tertiary Amylenes, The staiting material here is a fiaction which is cut from catal57tic clacking of petroleum. Two of the tertiary amylene isomers, 2-methyl-l-butene and 2-methyl-2-butene, are recovered in high purity by formation of methyl tertiary butyl ether and cracking of this to produce primarily 2-methyl-2-butene. The amylenes are mixed with steam and dehydrogenated over a catalyst. The cmde isoprene can be purified by conventional or extractive distillation. 

The speed of the reaction depends both on the metal and on the alcohol, increasing as electropositivity iacreases and decreasiag with length and branching of the chain. Thus sodium reacts strongly with ethanol, but slowly with tertiary butyl alcohol. The reaction with alkaU metals is sometimes carried out ia ether, ben2ene, or xylene. Some processes use the metal amalgam or hydride iastead of the free metal. Alkaline earth metals and aluminum are often covered with an oxide film which hinders the reaction. 

Ethyl Tertiary-Butyl Ether. Similar to methanol in the MTBE reaction, ethanol can react with isobutylene to produce ETBE. Which alcohol is used to make the ether is highly dependent on the relative cost of the alcohols. To make ethanol more economically competitive with methanol, the federal tax credit for biomass-based ethanol used in fuel also appHes to ethanol used to make ETBE in the United States (24). 

The process gas of ethylene plants and methyl tertiary butyl ether plants is normally a hydrogen/ methane mixture. The molecular weight of the gas in such processes ranges from 3.5 to 14. The tliermodynamic behavior of hydrogen/methane mixtures has been and continues to be extensively researched. The gas dynamic design of turboexpanders, which are extensively used in such plants, depends on the equations of state of the process gas. Optimum performance of the turboexpander and associated equipment demands accurate thermodynamic properties for a wide range of process gas conditions. 

The most common ethers being used as additives are methyl tertiary butyl ether (MTBE), and tertiary amyl methyl ether (TAME). Many of the larger refineries manufacture their own supplies of MTBE and TAME by reacting isobutylene and/or isoamylene with methanol. Smaller refineries usually buy their supplies from chemical manufacturers or the larger refineries. 

A solution of 7.5 grams of retroprogesterone in 500 ml of freshly distilled tertiary butyl alcohol was refluxed with 12.75 grams of finely powdered chloranil, while stirring, for 5 hours in a nitrogen atmosphere. After cooling, 2 liters of water were added and extraction was performed three times with 200 ml of methylene dichloride. The combined extracts were then diluted with 1 liter of petroleum ether (40°-60°C) washed successively with 100 ml of diluted Na2S04, four times with 75 ml of 1 N NaOH, and then water to neutral reaction. 

To a stirred solution of 1.00 gram of 17/3-hydroxy-17o -methyl-4-androsteno[3,2-c] pyrazole in 200 ml of tetrahydrofuran and 400 ml of liquid ammonia was added 2.12 grams of iithium wire during 5 minutes. The dark biue mixture was stirred for 45 minutes. A solution of 40 ml of tertiary-butyl alcohol in 160 ml of diethyl ether was added with stirring. 

In the United States, the leading use of alternative fuels is not as standalone fuels, but as additives to petroleum-based gasoline and diesel fuel. For example, gasoline sold m much of the United States is 10 percent ethanol or 10 percent methyl tertiary butyl ether (MTBE). 

Like propane, n-hutane is mainly obtained from natural gas liquids. It is also a hy-product from different refinery operations. Currently, the major use of n-hutane is to control the vapor pressure of product gasoline. Due to new regulations restricting the vapor pressure of gasolines, this use is expected to he substantially reduced. Surplus n-butane could be isomerized to isobutane, which is currently in high demand for producing isobutene. Isobutene is a precursor for methyl and ethyl tertiary butyl ethers, which are important octane number boosters. Another alternative outlet for surplus n-butane is its oxidation to maleic anhydride. Almost all new maleic anhydride processes are based on butane oxidation. 

In summary, ZSM-5 provides the refiner the flexibility to increase gasoline octane and light olefins. With the introduction of reformulated gasoline, ZSM-5 could play an important role in producing isobutylene, used as the feedstock for production of methyl tertiary butyl ether (MTBE). 

MTBE, where isobutylene is reacted with methanol to produce an oxygenate gasoline additive called methyl tertiary butyl ether (MTBE). MTBE is added to gasoline to meet the minimum oxygen requirement for reformulated gasoline. 

Oxygen was added as oxygenated hydrocarbon components methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), ethyl tert-butyl ether (ETBE), di-isopropyl ether (DIPE), ethanol, methanol, and tertiary butyl alcohol (TBA). The properties of oxygenates, as they relate to gasoline blending, are shown in Table 10-1. 

Methyl Tertiary Butyl Ether (MTBE) is an ether added to gasoline to improve its octane and reduce air pollution. 

Other major components in gasoline come from catalytic reforming, alkylation and the addition of an oxygenated octane booster, methyl tertiary-butyl ether (MTB E). 

Kado NY, PA Kuzmicky, G Loarca-Pina, MM Mumtaz (1998) Genotoxicity testing of methyl tertiary-butyl ether (MTBE) in the Salmonella microsuspension assay and mouse bone marrow micronucleus test Mut Res 412 131-138. 

Alternative solvents were also tested. Isopropanol and methyl tertiary-butyl ether (MTBE) with water (HCl), the latter a two-phase system, the displayed reaction rates were much slower. 

Methyl tertiary butyl ether (MTBE) is used as an anti-knock additive in petrol (gasoline). 

The most soluble gasoline compound is methyl tertiary-butyl ether (MTBE) (43,000 mg/L). In addition, MTBE in solution has a cosolvent effect, causing some of the other compounds in gasoline to solubilize at higher concentrations than they normally would in clean water. 

Prah, J., Ashley, D., Blount, B., Case, M., Leavens, T., Pleil, J., and Cardinali, F., Dermal, oral, and inhalation pharmacokinetics of methyl tertiary butyl ether (MTBE) in human volunteers, Toxicological Sciences, 77, 195-205, 2004. 

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