Fisher Tropsch Polymerization

Figure 11-9 Proposed mechanism for Fisher Tropsch polymerization of CO and H2 to form alkane polymer.

We next return to another reaction of a CO + H2 mixture, which we called synthesis gas or syngas. It has this name because it is used to synthesize many chemicals such as methanol. Another synthesis reaction from CO and H2 is a polymerization process called the Fisher Tropsch synthesis of synthetic diesel fuel. 

In contrast to the Fisher Tropsch synthesis of higher alkanes from CO and H2, Ni catalysts produce primarily methane, and Cu/ZnO catalysts produce mainly methanol. Sketch the mechanistic steps that favor these products rather than polymerization ... 

Hydrocarbon cracking processes, such as steam cracking or catalytic cracking, and Fisher-Tropsch synthesis produce significant amounts of light olefins (C2 to C5 fractions). Dimerization, co-dimerization, or polymerization reactions are widely used on an industrial scale either to provide chemicals of high value or to upgrade byproduct olefinic streams [1],... 

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