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Sang-eon Park - One of the best experts on this subject based on the ideXlab platform.
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An Overview on the Dehydrogenation of Alkylbenzenes with Carbon DiOxide over Supported Vanadium–Antimony Oxide Catalysts
Catalysis Surveys from Asia, 2007Co-Authors: Jong-san Chang, Vladislav P. Vislovskiy, Do-young Hong, Sang-eon ParkAbstract:Utilization of carbon diOxide as a soft oxidant for the catalytic dehydrogenation of ethylbenzene (CO_2-EBDH) has been recently attempted to explore a new technology for producing styrene selectively. This article summarizes the results of our recent attempts to develop effective catalyst systems for the CO_2-EBDH on the basis of alumina-supported vanadium Oxide catalysts. Its initial activity and on-stream stability were essentially improved by the introduction of Antimony Oxide as a promoter into the alumina-supported catalyst. Insertion of zirconium Oxide into alumina support substantially increased the catalytic activity. Modification of alumina with magnesium Oxide yielded an increase of catalyst stability of alumina-supported V–Sb Oxide due to the coking suppression. Carbon diOxide has been confirmed to play a beneficial role of selective oxidant in improving the catalytic performance through the oxidative pathway, avoiding excessive reduction and maintaining desirable oxidation state of vanadium ion (V^5+). The positive effect of carbon diOxide in dehydrogenation reactions of several alkylbenzenes such as 4-diethylbenzene, 4-ethyltoluene, and iso- and n- propylbenzenes was also observed. Along with the easier redox cycle between fully oxidized and partially reduced vanadium species, the optimal surface acidity of the catalyst is also responsible for achieving high activity and catalyst stability. It is highlighted that supra-equilibrium EBDH conversions were obtained over alumina-supported V–Sb Oxide catalyst in CO_2-EBDH as compared with those in steam-EBDH in the absence of carbon diOxide.
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Catalytic dehydrogenation of ethylbenzene with carbon diOxide: promotional effect of Antimony in supported vanadium–Antimony Oxide catalyst
Catalysis Today, 2003Co-Authors: Min-seok Park, Vladislav P. Vislovskiy, Jong-san Chang, Yong-gun Shul, Sang-eon ParkAbstract:Abstract Alumina-supported vanadium Oxide, VO x /Al 2 O 3 , and binary vanadium–Antimony Oxides, VSbO x /Al 2 O 3 , have been tested in the ethylbenzene dehydrogenation with carbon diOxide and characterized by S BET , X-ray diffraction, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction and CO 2 pulse methods. VSbO x /Al 2 O 3 exhibited enhanced catalytic activity and especially on-stream stability compared to VO x /Al 2 O 3 catalyst. Incorporation of Antimony into VO x /Al 2 O 3 increased dispersion of active VO x species, enhanced redox properties of the systems and formed a new mixed vanadium–Antimony Oxide phase in the most catalytically efficient V 0.43 Sb 0.57 O x /Al 2 O 3 system.
Jong-san Chang - One of the best experts on this subject based on the ideXlab platform.
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An Overview on the Dehydrogenation of Alkylbenzenes with Carbon DiOxide over Supported Vanadium–Antimony Oxide Catalysts
Catalysis Surveys from Asia, 2007Co-Authors: Jong-san Chang, Vladislav P. Vislovskiy, Do-young Hong, Sang-eon ParkAbstract:Utilization of carbon diOxide as a soft oxidant for the catalytic dehydrogenation of ethylbenzene (CO_2-EBDH) has been recently attempted to explore a new technology for producing styrene selectively. This article summarizes the results of our recent attempts to develop effective catalyst systems for the CO_2-EBDH on the basis of alumina-supported vanadium Oxide catalysts. Its initial activity and on-stream stability were essentially improved by the introduction of Antimony Oxide as a promoter into the alumina-supported catalyst. Insertion of zirconium Oxide into alumina support substantially increased the catalytic activity. Modification of alumina with magnesium Oxide yielded an increase of catalyst stability of alumina-supported V–Sb Oxide due to the coking suppression. Carbon diOxide has been confirmed to play a beneficial role of selective oxidant in improving the catalytic performance through the oxidative pathway, avoiding excessive reduction and maintaining desirable oxidation state of vanadium ion (V^5+). The positive effect of carbon diOxide in dehydrogenation reactions of several alkylbenzenes such as 4-diethylbenzene, 4-ethyltoluene, and iso- and n- propylbenzenes was also observed. Along with the easier redox cycle between fully oxidized and partially reduced vanadium species, the optimal surface acidity of the catalyst is also responsible for achieving high activity and catalyst stability. It is highlighted that supra-equilibrium EBDH conversions were obtained over alumina-supported V–Sb Oxide catalyst in CO_2-EBDH as compared with those in steam-EBDH in the absence of carbon diOxide.
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Catalytic dehydrogenation of ethylbenzene with carbon diOxide: promotional effect of Antimony in supported vanadium–Antimony Oxide catalyst
Catalysis Today, 2003Co-Authors: Min-seok Park, Vladislav P. Vislovskiy, Jong-san Chang, Yong-gun Shul, Sang-eon ParkAbstract:Abstract Alumina-supported vanadium Oxide, VO x /Al 2 O 3 , and binary vanadium–Antimony Oxides, VSbO x /Al 2 O 3 , have been tested in the ethylbenzene dehydrogenation with carbon diOxide and characterized by S BET , X-ray diffraction, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction and CO 2 pulse methods. VSbO x /Al 2 O 3 exhibited enhanced catalytic activity and especially on-stream stability compared to VO x /Al 2 O 3 catalyst. Incorporation of Antimony into VO x /Al 2 O 3 increased dispersion of active VO x species, enhanced redox properties of the systems and formed a new mixed vanadium–Antimony Oxide phase in the most catalytically efficient V 0.43 Sb 0.57 O x /Al 2 O 3 system.
Vladislav P. Vislovskiy - One of the best experts on this subject based on the ideXlab platform.
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An Overview on the Dehydrogenation of Alkylbenzenes with Carbon DiOxide over Supported Vanadium–Antimony Oxide Catalysts
Catalysis Surveys from Asia, 2007Co-Authors: Jong-san Chang, Vladislav P. Vislovskiy, Do-young Hong, Sang-eon ParkAbstract:Utilization of carbon diOxide as a soft oxidant for the catalytic dehydrogenation of ethylbenzene (CO_2-EBDH) has been recently attempted to explore a new technology for producing styrene selectively. This article summarizes the results of our recent attempts to develop effective catalyst systems for the CO_2-EBDH on the basis of alumina-supported vanadium Oxide catalysts. Its initial activity and on-stream stability were essentially improved by the introduction of Antimony Oxide as a promoter into the alumina-supported catalyst. Insertion of zirconium Oxide into alumina support substantially increased the catalytic activity. Modification of alumina with magnesium Oxide yielded an increase of catalyst stability of alumina-supported V–Sb Oxide due to the coking suppression. Carbon diOxide has been confirmed to play a beneficial role of selective oxidant in improving the catalytic performance through the oxidative pathway, avoiding excessive reduction and maintaining desirable oxidation state of vanadium ion (V^5+). The positive effect of carbon diOxide in dehydrogenation reactions of several alkylbenzenes such as 4-diethylbenzene, 4-ethyltoluene, and iso- and n- propylbenzenes was also observed. Along with the easier redox cycle between fully oxidized and partially reduced vanadium species, the optimal surface acidity of the catalyst is also responsible for achieving high activity and catalyst stability. It is highlighted that supra-equilibrium EBDH conversions were obtained over alumina-supported V–Sb Oxide catalyst in CO_2-EBDH as compared with those in steam-EBDH in the absence of carbon diOxide.
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Catalytic dehydrogenation of ethylbenzene with carbon diOxide: promotional effect of Antimony in supported vanadium–Antimony Oxide catalyst
Catalysis Today, 2003Co-Authors: Min-seok Park, Vladislav P. Vislovskiy, Jong-san Chang, Yong-gun Shul, Sang-eon ParkAbstract:Abstract Alumina-supported vanadium Oxide, VO x /Al 2 O 3 , and binary vanadium–Antimony Oxides, VSbO x /Al 2 O 3 , have been tested in the ethylbenzene dehydrogenation with carbon diOxide and characterized by S BET , X-ray diffraction, X-ray photoelectron spectroscopy, hydrogen temperature-programmed reduction and CO 2 pulse methods. VSbO x /Al 2 O 3 exhibited enhanced catalytic activity and especially on-stream stability compared to VO x /Al 2 O 3 catalyst. Incorporation of Antimony into VO x /Al 2 O 3 increased dispersion of active VO x species, enhanced redox properties of the systems and formed a new mixed vanadium–Antimony Oxide phase in the most catalytically efficient V 0.43 Sb 0.57 O x /Al 2 O 3 system.
Frank J. Berry - One of the best experts on this subject based on the ideXlab platform.
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Tin--Antimony Oxide oxidation catalysts
Hyperfine Interactions, 1998Co-Authors: Frank J. BerryAbstract:Tin--Antimony Oxide catalysts for the selective oxidation of hydrocarbons have been made by precipitation techniques. The dehydration of the amorphous dried precipitate by calcination at increasingly higher temperatures induces the crystallisation of a rutile-related tin diOxide-type phase and the segregation of Antimony Oxides which volatilise at elevated temperatures. The rutile-related tin diOxide-type phase contains Antimony(V) in the bulk and Antimony(III) in the surface. Specific catalytic activity for the oxidative dehydrogenation of butene to butadiene is associated with materials with large concentrations of Antimony(III) in the surface.
T A Tripolskaya - One of the best experts on this subject based on the ideXlab platform.
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the formation of a peroxoantimonate thin film coating on graphene Oxide go and the influence of the go on its transformation to Antimony Oxides and elemental Antimony
Carbon, 2012Co-Authors: Sergey Sladkevich, Alexey A. Mikhaylov, Alexander G. Medvedev, Petr V. Prikhodchenko, Vitaly Gutkin, T A TripolskayaAbstract:Abstract The ultrathin peroxoantimonate coating of graphene Oxide from hydrogen perOxide-rich solutions of hydroxoantimonate is demonstrated. An amorphous 1–2 nm Sb (V) Oxide film is formed and can be further crystallized by exposure to an electron beam to give a 2–5 nm thick supported Sb 6 O 13 particulate coating. Heat treatment of the peroxoantimonate yielded different crystalline Oxides, whereas in the presence of the graphene support only trigonal Sb (0) was produced by heat treatment in vacuum or an argon atmosphere. The graphene Oxide support is essential for the formation of the Sb (0) phase and even in air a substantial elemental Antimony was obtained. Whereas heat treatment of uncoated graphene Oxide in an inert atmosphere produces reduced graphene Oxide, the Antimony Oxide coated graphene Oxide is not reduced by the heat treatment. Only after the supported Antimony Oxide is reduced to give the trigonal Sb (0) phase the graphene Oxide was reduced by the heat treatment. The phases before and after the different heat treatments are characterized by electron and X-ray diffraction, thermal analysis, XPS studies, electron microscopy and wet chemistry.