MFI Zeolites in the Petroleum Industry

Marcilly, C., Zeolites in the petroleum industry , in Encyclopedia of Supramolecular Chemistry, Atwood, J. L., Steed, J. W., eds. Marcel Dekker New York, 2004 Vol. 2,pp. 1599-1609. 

The MFI class of channel zeolites, of which ZSM-5 is a member, are of enormous importance in the petrochemicals industry because of their shape-selective adsorption and transformation properties. The most well-known example is the selective synthesis and diffusion of p-xylene through ZSM-5, in preference to the 0- and m-isomers. Calcined zeolites such as ZSM-5 are able to carry out remarkable transformations upon normally unreactive organic molecules because of super-acid sites that exist 

Micropore filling, e.g cations, water, amines, salts 

The zeolites high acidity is also of crucial importance in the production of gasoline via the M-forming process. In gasoline, linear n-alkanes are relatively undesirable compared to their branched counterparts because of their lower octane numbers. Separation of linear and branched materials increases the value of the gasoline. Better still, if linear materials can be converted into branched species, 

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