Methanol gasoline additive

With aldehydes, primary alcohols readily form acetals, RCH(OR )2. Acetone also forms acetals (often called ketals), (CH2)2C(OR)2, in an exothermic reaction, but the equiUbrium concentration is small at ambient temperature. However, the methyl acetal of acetone, 2,2-dimethoxypropane [77-76-9] was once made commercially by reaction with methanol at low temperature for use as a gasoline additive (5). Isopropenyl methyl ether [116-11-OJ, useful as a hydroxyl blocking agent in urethane and epoxy polymer chemistry (6), is obtained in good yield by thermal pyrolysis of 2,2-dimethoxypropane. With other primary, secondary, and tertiary alcohols, the equiUbrium is progressively less favorable to the formation of ketals, in that order. However, acetals of acetone with other primary and secondary alcohols, and of other ketones, can be made from 2,2-dimethoxypropane by transacetalation procedures (7,8). Because they hydroly2e extensively, ketals of primary and especially secondary alcohols are effective water scavengers. 

The / f/-butanol (TBA) coproduct is purified for further use as a gasoline additive. Upon reaction with methanol, methyl tert-huty ether (MTBE) is produced. Alternatively the TBA is dehydrated to isobutylene which is further hydrogenated to isobutane for recycle ia the propylene oxide process. 

Some efforts were made in the early 1980s to employ isobutyl and -butyl alcohols as octane extenders in gasoline. American Methyl Corporation in 1983, under a special waiver of the 1977 Clean Air Act (24), marketed a gasoline blend called Petrocoal containing methanol and a C-4 alcohol which was principally isobutyl alcohol. About 10,000 t of isobutyl and 5000 t of -butyl alcohol were consumed in this appHcation (10). In 1984, the EPA attempted to rescind this waiver and demand for isobutyl alcohol as a gasoline additive dropped to 136.3 t (10). Ultimately, the waiver was rescinded and no isobutyl or -butyl alcohol has been marketed for gasoline additive end use since 1984. 

Methyl-te/t-butyl ether, a gasoline additive, is made from isobutene and methanol with distillation in a bed of acidic ion-exchange resin catalyst. The MTBE goes to the bottom with purity above 99 percent and unreacted materials overhead. 

Nature produces a tremendous amount of methyl aleohol, simply by the fermentation of wood, grass, and other materials made to some degree of eellulose. In faet, methyl aleohol is known as wood aleohol, along with names sueh as wood spirits and methanol (its proper name the proper names of all aleohols end in -ol). Methyl aleohol is a eolorless liquid with a eharaeteristie aleohol odor. It has a flash point of 54°F, and is highly toxie. It has too many eommereial uses to list here, but among them are as a denaturant for ethyl alcohol (the addition of the toxie ehemieal methyl aleohol to ethyl aleohol in order to form denatured aleohol), antifreezes, gasoline additives, and solvents. No further substitution of hydroxyl radieals is performed on methyl aleohol. 

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. 

Methanol is also formed as a byproduct when charcoal is made by heating wood in the absence of air. For this reason, it is sometimes called wood alcohol. Methanol is used in jet fuels and as a solvent, gasoline additive, and starting material for several industrial syntheses. It is a deadly poison ingestion of as little as 25 mL can be fatal. The antidote in this case is a solution of sodium hydrogen carbonate, NaHC03. 

The largest U.S. methanol markets were for producing the gasoline additive MTBE (methyl tertiary butyl ether) as well as formaldehyde and acetic acid. MTBE is being phased out since it has been found to contaminate water supplies. 

Methanol has been used to make MTBE, a gasoline additive now being phased out because of environmental concerns such as groundwater contamination. Although methanol exists in nature and degrades quickly, MTBE is a complex, compound that exhibits little degradation once released into the environment. 

Due to methanol s corrosivity and its affinity for water, it cannot be readily distributed in today s fuel infrastructure. Methanol burns with a nearly invisible flame. Available luminosity additives won t reform in the low-temperature methanol steam reformers. Methanol is more acutely toxic than gasoline. Additives that are likely to be needed for safety and health reasons will impact the fuel processor s performance and cost. 

Cost Is about 10-12/GJ for both methanol and synthetic gasoline for transportation usage. The additional conversion costs of methanol to gasoline by the Mobil process roughly balance the distribution and usage costs of methanol/gasoline blends. 

As we learned in Chapters 3 and 4, many inorganic compounds, not just ammonia, are derived from synthesis gas, made from methane by steam-reforming. In the top 50 this would include carbon dioxide, ammonia, nitric acid, ammonium nitrate, and urea. No further mention need be made of these important processes. We discussed MTBE in Chapter 7, Section 4, and Chapter 10, Section 9, since it is an important gasoline additive and C4 derivative. In Chapter 10, Section 6, we presented -butyraldehyde, made by the 0x0 process with propylene and synthesis gas, which is made from methane. In Chapter 11, Section 8, we discussed dimethyl terephthalate. Review these pertinent sections. That leaves only two chemicals, methanol and formaldehyde, as derivatives of methane that have not been discussed. We will take up the carbonylation of methanol to acetic acid, now the most important process for making this acid. Vinyl acetate is made from acetic... 

Methanol is a major chemical intermediate for production of acetic acid and the gasoline additive methyl-t-butylether (MTBE). It is an ideal fuel for several types of fuel cells, and there is discussion of using pure methanol as a replacement for gasoline. Therefore, methanol may soon become an even more important chemical. 

Methanol is used as a fuel additive. The common gasoline additive HEET is pure methanol and is used as a gas-line antifreeze and water remover. Methanol is used as a fuel in camp... 

Butyl alcohol, obtained from hydration of Raffinate I, can be dehydrated and subsequendy refined to high purity, polymer-grade isobutylene (25). Alternatively, the isobutylene from alcohol dehydration can react with methanol in the presence of an acid catalyst to give methyl /-butyl ether (MTBE) gasoline additive (see Ethers organic). 

CO + 2 H2 CH3OH ZnO and Cr203 Industrial synthesis of methanol CH3OH Manufacture of plastics, adhesives, gasoline additives industrial solvent... 

Methanol, also known as wood alcohol, is another widely discussed potential source (or carrier) of hydrogen.31 Chemically, methanol, ch oh, is a clear liquid, the simplest of the alcohols, with one carbon atom per molecule. Methanol is extensively used today— U.S. demand in 2002 exceeded 2 billion gallons. The largest U.S. methanol markets are for producing the gasoline additive mtbe (methyl tertiary butyl ether) as well as formaldehyde and acetic acid. 

Methanol. Methanol is a water-soluble, low molecular weight alcohol that may be of increasing importance as a low-sulfur fuel, a chemical feedstock, and perhaps as a gasoline additive or an intermediate in gasoline production. The synthesis of methanol is accomplished by the catalytic conversion of synthesis gas containing two moles of hydrogen for each mole of carbon monoxide. Methanol synthesis is widely practiced in industry on a commercial scale. See Chapter 10 for a discussion of methanol manufacture. 

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