Analytical rate expressions are derived from the full microkinetic model and fit to experimental data, capturing reaction order trends with similar success as the full model. Microkinetic analysis indicates that the SN2 and E2 elementary steps control the overall rate. The DFT-parameterized two-site mean-field microkinetic model successfully captures trends in experimentally measured reaction orders. DFT calculations on the cAl2O3(1 1 1) surface facet demonstrate that the energetically favorable pathway for ethylene formation is an E2 mechanism (Ea = 28 kcal/mol), while ether formation takes place via a bimolecular (SN2) mechanism (Ea = 32 kcal/mol). Keywords: c-Al2O3 Ethanol Dehydration Etherification Ethylene Diethyl ether Microkinetic model Lewis acid DFTĪ b s t r a c t We investigate the c-Al2O3-catalyzed production of ethylene and diethyl ether from ethanol in a combined density functional theory (DFT) and microkinetic modeling study.
Vlachos a,⇑ a Department of Chemical and Biomolecular Engineering, Catalysis Center for Energy Innovation and Center for Catalytic Science and Technology, University of Delaware, Newark, DE 19716-3110, USA b Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USAĪrticle history: Received Revised 5 December 2014 Accepted 21 December 2014 Christiansen a, Giannis Mpourmpakis b, Dionisios G. Journal of Catalysis journal homepage: DFT-driven multi-site microkinetic modeling of ethanol conversion to ethylene and diethyl ether on c-Al2O3(1 1 1) Matthew A. Contents lists available at ScienceDirect