Synthesis and characterization of hybrid organozeolites with high organic content

Different types of microporous hybrid organic–inorganic materials with ITQ-21, MFI and BEA structures have been synthesized from bridged organosiloxane precursors as silica sources. The methodology employed was similar to than for the synthesis of conventional zeolites. The organozeolites prepared contain the highest number of methylene and ethylene groups known up to now (∼9wt.% of carbon), into their typical inorganic frameworks, while maintaining high porosity and free porous volume. This effect is very marked in the organozeolites with Beta topology. The presence of organic fragments in the framework is confirmed by 13C and 29Si NMR and IR spectroscopies. The organic–inorganic networks are thermally stable and remain after elimination of the structure directing agents (SDAs) by calcination. Characterization techniques show that the type of structure finally crystallized and the crystallinity achieved are key parameters to introduce high carbon content into the zeolitic frameworks. The hybrid organic–inorganic materials synthesized, with incipient structuration level, present the conventional morphology and textural properties of zeolitic materials.