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In view of the latest critical energy situation in the Western world, extensive research is being conducted to reconsider the potentialities of other non-petroleum materials to become important sources of fuels. In particular, considerable efforts are expanded to develop and improve the various existing technologies for the conversion of coal, heavy petroleum residues, tar sands, shale and biomass, to gasoline. The Bergius (1) and Fischer-Tropsch (2) processes are among the best known that are currently used to produce gasoline from coal.

Solid intermediate phases obtained from amorphous aluminosilicate gels during mordenite crystallization have been characterized by multinuclear solid-state NMR spectroscopy. The progressive reorganization of the amorphous gel into the crystalline ordered zeolitic phase has been detected by high resolution magic-angle-spinning (HRMAS) solid state 29Si-NMR. Broad band solid state 27Al and 23Na-NMR were used to follow the incorporation of Al- and Na-atoms into the mordenite lattice and channels. An evidence of aluminium gradient in the crystallites is obtained from the comparison between surface and bulk analysis methods.

The structure of various natural and synthetic zeolites was investigated by high resolution magic-angle-spinning (HRMAS) solid state 29Si-NMR spectroscopy. The NMR analysis is based on the great sensitivity of the 29Si-chemical shifts either on the chemical environment (i.e. the number of aluminium atoms in the second coordination shell of silicon), on the crystal symmetry (i.e. the number of crystallographically different sites) or on local strains in the crystal.