CATALYTIC PROPERTIES OF HIGH-SILICA ZEOLITES SYNTHESIZED IN MIXTURES OF WATER AND ORGANIC-SOLVENT

The catalytic properties of ISI-1, 3, 4, 5 and 6, synthesized in mixtures of water and organic solvent, have been studied. Although having acidic properties similar to a sample of ZSM-5 zeolite comprising small and aggregated crystallites, the five zeolites showed low selectivities for C5+ product and fraction of aromatics in the C5+ product in syngas-to-gasoline and methanol-to-gasoline reactions. Under methanol-to-gasoline reaction conditions, ISI-3, 4, 5 and 6 showed a high production of p-xylene in the xylene product. From the results of physicochemical measurements, the unique catalytic properties of each ISI zeolite can be attributed to its crystal structure, pore size and large crystallite size.