Beyond traditional synthesis of zeolites : the impact of germanosilicate chemistry in the search for new materials

Abstract

Zeolites are one of the key materials in the chemical industry with their applications ranging from water purification to gas separation or oil refining. In the recent years, the research of zeolites focuses more and more on specialised applications including fine chemical synthesis or separation of small organic compounds, which increase the demand for new types of zeolites with unique structural and chemical properties. Introduction of tailored organic structure-directing agents and especially the introduction of germanium stimulated the discovery of new zeolite frameworks and particularly led to a discovery of numerous new extra-large pore zeolites with attractive properties for selective catalysis. However, the germanosilicate chemistry also opened up an unparalleled opportunity for tailoring even more new zeolites and zeolite-derived materials by controlled post-synthetic transformation of the germanosilicates into layered zeolites or to new zeolite frameworks by solid-, liquid- or vapour-phase transformations such as the Assembly-Disassembly-Organisation-Reassembly process. The following research provided new strategies for preparation of porous materials with characteristics and properties tailored on-demand.