Zeolite describes a broad class of micro-porous materials with crystalline walls and unique internal pore systems. An 18th century mineralogist coined in the term zeolite to describe strange “boiling rocks” that evolved copious amounts of water when heated. Zeolites are now pervasively used as adsorbents with applications in products as common as air-freshener, cat-litter and laundry detergent. Organic chemists utilize zeolites to remove water from organic solvents, a.k.a. Mol-Sieve 4A. Catalysis is the major use of zeolites in this country (over 1 billion pounds) and is the primary focus of our research. Zeolites are very stable forms of solid acidity when metals with Lewis-acid character are incorporated into a predominately silicon-oxygen lattice, e.g., Al and B. More recently zeolites have been used as stable partial oxidation catalysts with redox-metals, e.g., Ti and V, incorporated in the framework. Shape-Selective catalysis can be performed inside the zeolite’s cavities to give a single product. The earliest application of zeolite selective catalysis is the alkylation of toluene to give exclusively para-xylene (key intermediate for many polymers). Zeolites with a variety of accessible pore sizes and geometries are being synthesized and studied in our laboratory. Examples include zeolites with structures MFI, IFT, AFI. These materials have different names according to patents held for various elemental compositions.
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