Modeling the effects of Acid Site Location, Pairing, and Diffusion during Zeolite-Catalyzed Reactions

David Hibbitts from University of Florida
Melcher Hall rm 170

Zeolites are materials with pores and voids of molecular dimensions and thus are useful materials for sorption, separations, and catalysis. Proton-form zeolites contain Brønsted acid sites capable of catalyzing reactions such as hydrocarbon methylation, alkene oligomerization, and alcohol dehydration. This seminar will focus on ways in which we have modeled zeolite-catalyzed reactions using density functional theory (DFT) calculations in order to interrogate reaction mechanisms as well as the role of acid-site location, pairing, and zeolite crystal size and shape. We will focus on two applications: methanol dehydration to dimethyl ether which serves as a probe reaction to examine the effects of acid site location and pairing; and methanol-to-olefins which is a very complex reaction that rapidly deactivates in which molecular diffusion plays a strong role.