Computational QM/MM investigation of the adsorption of MTH active species in H-Y and H-ZSM-5

Stefan Nastase, Alexander O'Malley, C. Richard A. Catlow, Andrew Logsdail

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)

Abstract

The transformation of methanol-to-hydrocarbons (MTH) has significant potential as a route to synthesise low-cost fuels; however, the initial stages of the zeolite catalysed MTH process are not well understood. Here, we use hybrid quantum- and molecular-mechanical (QM/MM) embedded-cluster simulations to develop our understanding of the interaction between methanol and the zeolite catalysts H-ZSM-5, and for comparison, the larger pore H-Y. Energies and structures, calculated using hybrid-level density functional theory (hybrid-DFT) and higher-level correlated methods, are compared with previous experimental and computational results. We show that hydrogen-bonds between methanol adsorbates, formed through polarizable O–H bonds, substantially influence the adsorption energetics, structural parameters and vibrational frequencies. Our observations are extended by considering polar solvent molecules in the environment, with the presence of both water or methanol around the adsorption site leading to barrier-less transfer of the zeolite proton to an adsorbed methanol, which will significantly influence the reactivity of the adsorbed methanol.
Original languageEnglish
Pages (from-to)2639-2650
Number of pages11
JournalPhysical Chemistry Chemical Physics
Volume21
Issue number5
Early online date21 Dec 2018
Publication statusE-pub ahead of print - 21 Dec 2018

Fingerprint

Dive into the research topics of 'Computational QM/MM investigation of the adsorption of MTH active species in H-Y and H-ZSM-5'. Together they form a unique fingerprint.

Cite this