Gasoline manufacture from methanol

Gasoline and distillate fuels can be produced via methanol as illustrated schematically in Fig. 1. Synthesis gas can be manufactured from natural gas by steam reforming, or from coal by partial oxidation. Since synthesis gas manufacture, and methanol synthesis, represent the largest cost in synthetic fuels production, considerable effort has been dedicated to improving... 

Methyl terf-butyl ether (MTBE) is an important industrial product used as oxygenate additive in reformulated gasoline. Environmental concern makes its future uncertain, however. Although mainly manufactured by reaction of isobutylene with methanol, it is also produced commercially from methanol and fcrr-butyl alcohol, a by-product of propylene oxide manufacture. Numerous observations from the use of heteropoly acids have been reported. These compounds were used either as neat acids [74], or supported on oxides [75], silica or K-10 montmorillonite [76]. They were also used in silica-included form [77] and as acidic cesium salts [74,77]. Other catalysts studied were sulfated ZrOj [76], Amberlyst 15 ion-exchange resin [76], HZSM-5 [76], HF-treated montmorillonite, and commercial mineral acid-activated clays [75]. Hydrogen fluoride-treatment of montmorillonite has been shown to furnish particularly active and stable acid sites thereby ensuring high MTBE selectivity (up to 94% at 413 K) [75]. 

The conversion of biomass materials to high octane gasoline has been actively pursued for many years. Historically, methanol was made in very low yields by the destructive distillation of hardwoods. More recently, the manufacture of methanol has been by the reaction of synthesis gas over catalysts at high pressures. In theory, any carbon source can be used for this catalytic generation of methanol, but in practice, biomass has not been advantageous relative to coal or natural gas. Other approaches to making liquid fuel from biomass have involved the fermentation of biomass to ethanol in a rather slow process. The conversion of biomass to alcohols is technically feasible, but the utilization of the alcohols as transportation fuels will require modifications to the... 

In 1984 methyl t-butyl ether (MTBE) broke into the top 50 for the first time with a meteoric rise in production from 0.8 billion lb in 1983 to 1.47 billion lb in 1984 to be ranked 47. In 1990 it was 24 with production over 6 billion lb, and in 1995 it was 12 at 18 billion lb. A full discussion of the current economic status of MTBE is given in Chapter 7, Section 4 as the important gasoline octane enhancer. That is its only major use. MTBE is manufactured by the acid catalyzed electrophilic addition of methanol to isobutylene. 

Like ammonia, methanol has a great many practical uses in a variety of industries. The most important use of methanol is in the manufacture of other chemicals, such as those from which plastics are made. Small amounts are used as additives to gasoline to reduce the amount of pollution released to the environment. Methanol is also used widely as a solvent (to dissolve other materials) in industry. 

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