Catalytic Dehydrogenation of Light Alkanes on Metals and Metal Oxides

2014 ◽  
Vol 114 (20) ◽  
pp. 10613-10653 ◽  
Author(s):  
Jesper J. H. B. Sattler ◽  
Javier Ruiz-Martinez ◽  
Eduardo Santillan-Jimenez ◽  
Bert M. Weckhuysen
Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2234
Author(s):  
Zhe Feng ◽  
Xin Liu ◽  
Yu Wang ◽  
Changgong Meng

Light olefins are key components of modern chemical industry and are feedstocks for the production of many commodity chemicals widely used in our daily life. It would be of great economic significance to convert light alkanes, produced during the refining of crude oil or extracted during the processing of natural gas selectively to value-added products, such as light alkenes, aromatic hydrocarbons, etc., through catalytic dehydrogenation. Among various catalysts developed, Ga-modified ZSM-5-based catalysts exhibit superior catalytic performance and stability in dehydrogenation of light alkanes. In this mini review, we summarize the progress on synthesis and application of Ga-modified ZSM-5 as catalysts in dehydrogenation of light alkanes to olefins, and the dehydroaromatization to aromatics in the past two decades, as well as the discussions on in-situ formation and evolution of reactive Ga species as catalytic centers and the reaction mechanisms.


2015 ◽  
Vol 6 (8) ◽  
pp. 4403-4425 ◽  
Author(s):  
Zhi-Jian Zhao ◽  
Cheng-chau Chiu ◽  
Jinlong Gong

This review describes recent progress on mechanistic understanding of heterogeneous catalytic dehydrogenation reactions of light alkanes.


Author(s):  
R. Ai ◽  
H.-J. Fan ◽  
L. D. Marks

It has been known for a long time that electron irradiation induces damage in maximal valence transition metal oxides such as TiO2, V2O5, and WO3, of which transition metal ions have an empty d-shell. This type of damage is excited by electronic transition and can be explained by the Knoteck-Feibelman mechanism (K-F mechanism). Although the K-F mechanism predicts that no damage should occur in transition metal oxides of which the transition metal ions have a partially filled d-shell, namely submaximal valence transition metal oxides, our recent study on ReO3 shows that submaximal valence transition metal oxides undergo damage during electron irradiation.ReO3 has a nearly cubic structure and contains a single unit in its cell: a = 3.73 Å, and α = 89°34'. TEM specimens were prepared by depositing dry powders onto a holey carbon film supported on a copper grid. Specimens were examined in Hitachi H-9000 and UHV H-9000 electron microscopes both operated at 300 keV accelerating voltage. The electron beam flux was maintained at about 10 A/cm2 during the observation.


Author(s):  
Michel Fialin ◽  
Guy Rémond

Oxygen-bearing minerals are generally strong insulators (e.g. silicates), or if not (e.g. transition metal oxides), they are included within a rock matrix which electrically isolates them from the sample holder contacts. In this respect, a thin carbon layer (150 Å in our laboratory) is evaporated on the sections in order to restore the conductivity. For silicates, overestimated oxygen concentrations are usually noted when transition metal oxides are used as standards. These trends corroborate the results of Bastin and Heijligers on MgO, Al2O3 and SiO2. According to our experiments, these errors are independent of the accelerating voltage used (fig.l).Owing to the low density of preexisting defects within the Al2O3 single-crystal, no significant charge buildup occurs under irradiation at low accelerating voltage (< 10keV). As a consequence, neither beam instabilities, due to electrical discharges within the excited volume, nor losses of energy for beam electrons before striking the sample, due to the presence of the electrostatic charge-induced potential, are noted : measurements from both coated and uncoated samples give comparable results which demonstrates that the carbon coating is not the cause of the observed errors.


1977 ◽  
Vol 38 (C1) ◽  
pp. C1-333-C1-336 ◽  
Author(s):  
P. CAVALLOTTI ◽  
R. ROBERTI ◽  
G. CAIRONI ◽  
G. ASTI

2014 ◽  
Vol 59 (4) ◽  
pp. 401-404
Author(s):  
G.S. Dragan ◽  
◽  
K.V. Kolesnikov ◽  
V.M. Ulianytskyi ◽  
◽  
...  

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