Role of Alkali Cations During Interzeolite Conversion

Zeolites are porous crystalline aluminosilicates that have a variety of industrial applications. The synthesis of zeolites is a complex and poorly understood process. Thus, this thesis focuses on elucidating the roles of alkali cations during the transformation of one zeolite into another, known as interzeolite conversion (IZC). Ex situ time resolved IZCs were performed, starting from FAU-type zeolites with different Si/Al ratios, and using Li+, Na+, K+, and Rb+ as the alkali cations. The findings of this work indicate that the process is driven by changes of the Si/Al ratio of the solid product and the incorporation of alkali cations, in sites with few steric constrains and with ideal coordination environments, within the zeolite product. Such factors promote the formation of specific substructures which can facilitate the formation of specific zeolite frameworks. The findings of this thesis may serve as a guideline for the selection of starting conditions during IZC.