Forty Years of Designing Catalytic and Adsorptive Sites in FAU Type Zeolites at K.U. Leuven

Abstract

An overview of scientific achievements at K.U. Leuven on the design and characterization of active sites in X and Y zeolites and on the development of adsorptive and catalytic processes in which these active sites are operated is provided. The historical development of this research area and the scientific progress are presented. Zeolite Y and ultrastabilized specimen present Brønsted and Lewis sites that can be operated in vapor and liquid phase hydrocarbon conversion processes, bifunctional catalysis, epoxidation and ring opening of epoxides. Examples of molecular shape selective catalysis with Y zeolites are presented. The redox chemistry of transition metal exchanged faujasites is understood in great detail and has been exploited in Wacker chemistry and water splitting in a photochemicalthermal cycle. Selective adsorbents were designed based on knowledge of cation siting in X and Y zeolites. The occlusion of coordination compounds in the faujasite supercages is a means of creating unique active sites. Catalytic oxidative properties of the enzymes can be mimicked by embedding zeozyme in a hydrophobic membrane.

Elucidating and Tuning Catalytic Sites on Zirconium- and Aluminum-Containing Nodes of Stable Metal–Organic Frameworks

“…Rehydration reactions on metal oxides are complicated, depending on the temperature of the prior dehydration. The dehydration/hydration process is sometimes almost reversible when the dehydration temperature is moderate (e.g., 250 °C), but rearrangements of bulk oxide lattices and the formation of new phases complicate matters at higher temperatures. , The rehydration of metal oxides/zeolites sometimes takes days or even months . Similarly, the rehydration reactions of the MOF nodes mentioned here are complex and often slow.…”