Converting methanol into gasoline

At the low-molecular-weight end of the spectrum, a process newly commercialized by Mobil for converting methanol into gasoline has significantly expanded opportunities in C-1 chemistry— the upgrading of one-carbon molectrles to mrrlticarbon products. The process involves the use of ZSM-5, a shape-selective zeolite catalyst. (See "Zeolite and Shape-Selective Catalysts" in Chapter 9.)... 

Figure 11.6 Process steps for converting methanol into gasoline and olefins and resins...

These catalysts provide three-dimensional microscopic media for reaction. The most important are the zeolites (see 14.2.2.2). Faujasites are used to crack petroleum for the manufacture of gasoline, and HZSM-5 to convert methanol into gasoline and in other petrochemical conversion processes including xylene isomerization and toluene di sproportionation. ... 

Figure 3.51 Flow diagram for the Mobil Oil fixed-bed process to convert methanol into gasoline...

CONVERTING METHANOL INTO GASOLINE IN A NOVEL PSEUDOADIABATIC CATALYTIC FIXED BED REACTOR... 

Catalysts in the ZSM-5 and ZSM-11 family are used to convert methanol into high octane gasoline components in the Mobil MTG process (45). 

Mobil Oil Corporation has developed a process on a pilot scale that can successfully convert methanol into 96 octane gasoline. Although methanol can be used directiy as a transportation fuel, conversion to gasoline would eliminate the need to modify engines and would also eliminate some of the problems encountered using gasoline—methanol blends (see Alcohol fuels Gasoline and other motor fuels). 

Mobil has developed a method for converting methanol to gasoline and in 1986 the government of New Zealand constructed a plant capable of using the process to produce 627,000 tons of gasoline per year.184 The method utilizes the zeolite ZSM-5 as catalyst (Fig. 1.1).1 5 The zeolite acts as an acid catalyst and effectively eliminates a molecule of water from the methanol. The resulting carbene may be stabilized by the zeolite before inserting into another molecule of methanol. The details of the mechanism are not clear,186 but the overall reaction may be written ... 

NExETHERS A process for converting C5, C6, and C7 olefins to ethers for blending into gasoline to increase its octane rating. The process resembles Nextame but uses additional methanol to increase the yield of ethers. 

Onboard reforming for fuel cells depends on catalytic reactions to convert conventional hydrocarbon fuels, such as gasoline or methanol, into hydrogen that fuel cells can then use to produce electricity to power vehicles. 

Methanol can be used directly as a transportation fuel, or it can be converted into gasoline with catalysts such as the ZSM-5 zeolite catalyst. 

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