Zeolite-catalyzed dehydration of ethanol offers promising perspectives for the sustainable production of ethene. Complex parallel-consecutive pathways are proposed to be involved in the reaction network of ethanol dehydration on zeolites, where the initial step of ethanol dehydration is still unclear particularly for the favorable production of ethene at lower temperature. Here we report the observation of a triethyloxonium ion (TEO) in the dehydration of ethanol on zeolite H-ZSM-5 by using ex situ and in situ solid-state NMR spectroscopy. TEO is identified as a stable surface species on the working catalyst, which shows high reactivity during reaction. Ethylation of the zeolite by TEO occurs at lower temperature, leading to the formation of surface ethoxy species and then ethene. The TEO-ethoxide pathway is found to be energetically preferable for the dehydration of ethanol to ethene in the initial stage, which is also supported by theoretical calculations.
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http://dx.doi.org/10.1038/s41467-019-09956-7 | DOI Listing |
Sci Rep
January 2025
Department of Pesticide Chemistry, National Research Centre, Dokki, 12622, Giza, Egypt.
Targeted therapy is preferable over other therapeutics due to its limitation of drawbacks and better pharmaceutical outcomes. VEGF and its receptors have been observed to be hyper-activated in many cancer types and are considered promising targets for assigning anticancer agents. The current study is directed towards synthesis of novel antiproliferative 2-oxoindolin-3-ylidenes incorporating urea function with VEGFR-2 properties.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Department of Agricultural Engineering, College of Engineering, China Agricultural University, Beijing 100083, China.
This study aims to explore the redispersibility of dehydrated nanocellulose with p-toluenesulfonic acid (p-TsOH) fractionated lignin as an eco-friendly and cost-effective capping agent, to cope with the challenge of irreversible agglomeration and thus loss of nanoscale of nanocellulose upon dehydration. The intermixing of nanocellulose and p-TsOH fractionated lignin was achieved using an aqueous ethanol solution as the medium and films of lignin-blending cellulose nanofibers (L + CNF) with excellent redispersing properties were obtained after facile air-drying. With 0.
View Article and Find Full Text PDFACS Omega
December 2024
Department of Chemistry, Faculty of Science, Chiang Mai University, 239 Houy Kaew Road, Chiang Mai 50200, Thailand.
To examine the water-induced photoluminescence turn-on and its potential application in trace water sensing, a new series of [Ln(dmba)(HO)]·2HO, where Ln = La (), Pr (), Nd (), Sm (), Eu (), Gd (), Tb (), Dy (), Ho (), and Er (), were synthesized using dimethoxybenzoic acid (Hdmba). Their single-crystal structures and thermal and chemical robustness were investigated, and the effects of lanthanide contraction and noncovalent interactions were discussed. The photoluminescence and colorimetric properties of - were investigated.
View Article and Find Full Text PDFInt J Biol Macromol
December 2024
Core Facility Center "Arktika" Northern (Arctic) Federal University named after M.V. Lomonosov, Northern Dvina Emb., 17, Arkhangelsk 163002, Russia. Electronic address:
The widespread development of lignin valorization is hindered by a number of challenges. In particular, efficient valorization necessitates comprehensive characterization of initial lignins. In this work, the structural features of lignins from birch wood (Bétula péndula), obtained by various methods of hard and mild fractionation of biomass: hydrolysis (Hyd-L), kraft (Kraft-L), soda (Soda-L), and soda-ethanol (SodaEt-L) processes, as well as organosolv processes with dioxane (MWL, DL) and dimethyl sulfoxide (DMSO-L) have been comprehensively studied.
View Article and Find Full Text PDFJ Phys Chem Lett
December 2024
National 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.
γ-AlO 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-AlO that facilitate ethanol dehydration.
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