Related Experiment Video
Updated: Jun 4, 2025

Facile Preparation of Ultrafine Aluminum Hydroxide Particles with or without Mesoporous MCM-41 in Ambient Environments
Published on: May 11, 2017
Unveiling Active Al3+ Sites for Ethanol Dehydration on γ-Al2O3 with Solid-State Nuclear Magnetic Resonance
Xue Zhou1,2, Yueying Chu1, Chao Wang1
1National Centre for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China.
Abstract:
γ-Al2O3 is a crucial catalyst widely used in industrial alcohol dehydration processes. However, the specific nature of its active sites has remained unclear. In this study, we utilize two-dimensional heteronuclear correlation solid-state nuclear magnetic resonance and density functional theory calculations to uncover the active Al sites on the surface of γ-Al2O3 that facilitate ethanol dehydration. We show the formation of stable pentacoordinated AlV-ethanol complexes upon the adsorption of ethanol on the tetracoordinated AlIV sites. This interaction significantly enhances synergy with adjacent AlV-OH sites, resulting in a marked reduction of the activation energy barrier for ethene production. Furthermore, we reveal an interchange between AlIV and AlV-OH species, allowing hexacoordinated AlVI-OH sites to participate in the dehydration pathway through the migration of ethanol between these coordination sites.
More Related Videos
Related Concept Videos
NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones
Dehydration of Aldols to Enals: Base-Catalyzed Aldol Condensation
¹H NMR of Labile Protons: Temporal Resolution
The –OH proton in alcohols typically appears in the range of δ 2 to 5 ppm but can vary depending on the specific...
Acid-Catalyzed Dehydration of Alcohols to Alkenes
Dehydration of Aldols to Enones: Acid-Catalyzed Aldol Condensation
Aldehydes and Ketones with Water: Hydrate Formation
The formation of hydrates is a reversible reaction. Hydrate formation is influenced by steric and electronic factors accompanying the alkyl substituents on the carbonyl group: The rate of hydrate formation increases with a decrease in the number of alkyl groups attached to the carbonyl carbon. Hence,...

