Zeolite Catalysis
نویسندگان
چکیده
The Special Issue “Zeolite Catalysis” published in the online journal Catalysts was recently successfully completed. A good number of peer-reviewed publications were published reflecting the broadness of the zeolite syntheses, characterizations and various application fields. This issue brought together recent research of well-known research teams from all over the world. The term “zeolite” is based on the Greek words for “to boil” and “stone” and it has been known since 250 years ago. At that time, the Swedish mineralogist, A.F. Cronstedt (1722–1765), observed the formation of a large amount of steam when heating the material Stilbite which indicated its porous character and adsorption capacity. At present, over 200 different zeolite frameworks have been identified. In general, zeolites are crystalline aluminosilicates with a defined micropore structure. Within zeolites, a good number of elements can be isomorphously incorporated and much more elements or their oxides can be hosted by zeolites. In addition, zeolites comprise a large variety in size of pore mouths, channels, crossings, etc. leading also to their designation as molecular sieves and use in membrane applications. Nowadays, various hierarchical and composite materials are designed offering further interesting properties, e.g., by the introduction of mesopores or generation of fibers. Zeolites reveal Brønsted and Lewis acidic properties that can be varied in wide limits as well. Thus, they deserve the name “solid acids”. Zeolites have an immense importance in diverse industrial applications such as catalysts and adsorbents, for example in the refinery industry, chemical industry, detergent sector or for solar thermal collectors and adsorption refrigeration.
منابع مشابه
Facile synthesis of H-type zeolite shell on a silica substrate for tandem catalysis.
A new class of silica-based zeolite capsule catalyst was readily prepared employing a dual-layer method under close-to-neutral conditions. In a tandem catalysis process, the precisely controlled synthesis of dimethyl ether was realized. This new concept of H-type zeolite shell preparation and application represents a powerful approach for preparing high-performance, multifunctional catalysts.
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