共查询到20条相似文献,搜索用时 15 毫秒
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G. V. Isagulyants L. I. Kovalenko A. A. Greish T. N. Shakhtakhtinskii F. V. Aliev R. R. Khankishev A. D. Kuliev 《Russian Chemical Bulletin》1986,35(4):707-710
Conclusions It has been shown by application of the kinetic isotope method that in the oxidative dehydrogenation of ethylbenzene to styrene on a magnesium ferrite catalyst, benzene and toluene are formed from ethylbenzene and also from styrene. Carbon dioxide appears mainly as a result of exhaustive oxidation of the side chain of the aromatic hydrocarbon.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 778–781, April, 1986. 相似文献
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Rui Han Jiangyong Diao Sonu Kumar Andrey Lyalin Tetsuya Taketsugu Gilberto Casillas Christopher Richardson Feng Liu Chang Won Yoon Hongyang Liu Xudong Sun Zhenguo Huang 《Journal of Energy Chemistry》2021,(6):477-484
It is demonstrated experimentally and confirmed theoretically that highly defective boron nitride showed outstanding performance for oxidative dehydrogenation o... 相似文献
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Kh. M. Alimardanov F. M. Velieva A. A. Dzhalilova N. M. Ragimova 《Russian Journal of Applied Chemistry》2013,86(7):971-978
In promotion of a Pt-Ga-containing pentasil with a binary mixture of REE oxides, a synergism of their effect on the catalyst activity in the reaction of oxidative dehydrogenation of 4-vinylcyclohexene is observed. A kinetic model of the process of oxidative dehydrogenation of 4-vinylcyclohexene is suggested. The model includes a stage-by-stage scheme and the corresponding reaction rate equations. It was found that the accumulation rate of 4-vinylcyclohexene dehydrogenation products is correlated with the isomerization capacity of the catalytic system. 相似文献
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Dehydrogenation of ethylbenzene (EB) to styrene over iron oxide-based catalyst is an important industrial catalytic process. A great deal of insight into this reaction has been accomplished by surface science studies of the model catalysts. However, molecular understanding still lacks in the removal of the resultant hydrogen from the oxide surface. Employing gas-phase atomic hydrogen, we successfully prepared hydroxyls on an alpha-Fe2O3(0001) film with biphase surface structure under ultrahigh-vacuum conditions. Upon heating, hydroxyls react to form hydrogen and water, the latter of which results in the partial reduction of Fe2O3. These results add important insight into the complete understanding of the catalytic cycle of dehydrogenation of ethylbenzene to styrene over iron oxide-based catalyst. 相似文献
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Shuwei Chen Zheqi Xu Dongchen Tan Dahai Pan Xingyu Cui Yan Qiao Ruifeng Li 《应用有机金属化学》2020,34(2):e5396
Catalytic performance of Al-MCM-41-supported vanadia catalysts (V/Al-MCM-41) with different V loading was investigated for oxidative dehydrogenation of ethylbenzene to styrene (ST) with CO2 (CO2-ODEB). For comparison, pure silica MCM-41 was also used as support for vanadia catalyst. The catalysts were characterized by N2 adsorption, X-ray diffraction (XRD) pyridine-Fourier-transform infrared spectroscopy, H2-temperature-programmed reduction, thermogravimetric analysis (TGA), UV-Raman, and diffuse reflectance (DR) UV–vis spectroscopy. The results indicate that the catalytic behavior and the nature of V species depend strongly on the V loading and the support properties. Compared with the MCM-41-supported catalyst, the Al-MCM-41-supported vanadia catalyst exhibits much higher catalytic activity and stability along with a high ST selectivity (>98%). The superior catalytic performance of the present V/Al-MCM-41 catalyst can be attributed to the Al-MCM-41 support being more favorable for the high dispersion of V species and the stabilization of active V5+ species. Together with the characterization results of XRD, TGA, and DR UV–Vis spectroscopy, the deep reduction of V5+ into V3+ during CO2-ODEB is the main reason for the deactivation of the supported vanadia catalyst, while the coke deposition has a less important impact on the catalyst stability. 相似文献
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Al的加入对CeZr固溶体催化剂结构及其乙苯脱氢活性的影响 《燃料化学学报》2017,45(2):189-193
为进一步提高铈锆固溶体储放氧性能,增强乙苯二氧化碳氧化脱氢反应性能,采用共沉淀法合成出氧化铝质量比为50%的铈锆铝氧化物催化剂。通过现代仪器分析表征技术,研究了Al加入对铈锆固溶体复合氧化物晶体结构、储放氧能力的影响。结果表明,Al的加入可起到"扩散阻碍"作用,且有效抑制铈锆固溶体晶粒长大,使得铈锆铝氧化物催化剂比表面积较铈锆固溶体增加了51.8 m~2/g,储放氧性OSC值提高了69.4μmol/g,将铈锆铝氧化物催化剂用在乙苯氧化脱氢5 h反应中,发现乙苯转化率提高了10%。 相似文献
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T. G. Alkhazov A. E. Lisovskii T. Kh. Gulakhmedova 《Reaction Kinetics and Catalysis Letters》1979,12(2):189-193
The oxidative dehydrogenation of ethylbenzene over a charcoal catalyst has been studied by the pulse technique. The styrene yields for the oxidation of ethylbenzene by gaseous oxygen and upon the interaction of ethylbenzene with oxygen adsorbed on charcoal are shown to be the same.
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《Reaction Kinetics and Catalysis Letters》2003,80(2):359-364
The effect of zinc on the performance of hematite-based catalysts in ethylbenzene dehydrogenation was studied. Zinc acts as
a structural promoter stabilizing the active phase of the catalysts.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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《Arabian Journal of Chemistry》2020,13(10):7357-7369
Nano-sheets Al2O3 supported CeO2-Fe2O3 binary oxides were prepared by the vacuum impregnation method. The structural and textural properties were characterized by pertinent techniques, and the materials were evaluated as catalysts for the oxidative dehydrogenation of ethylbenzene with carbon dioxide (CO2-ODEB). The characterization results show that all samples maintain the hierarchical structure, and CeO2-like and Fe2O3-like solid solutions were formed when changing the Ce-to-Fe molar ratio. The catalytic performances indicate that CeO2-Fe2O3 binary oxides were effective for CO2-ODEB, and the activity is determined by mobile oxygen, which can facilitate the dehydrogenation process. The DFT studies further identified the reaction pathway and rate-determining step. The inter-transmission of oxygen species and the presence of CO2 refill the oxygen vacancies and restore the redox cycle of CeO2-Fe2O3 binary oxides. 相似文献
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Tiago Pinheiro Braga Ant?nio Narcísio Pinheiro Edson R. Leite Regina Cláudia R. dos Santos Antoninho Valentini 《催化学报》2015,(5)
Molybdenum-based catalysts supported on Al2O3 doped with Ni, Cu, or Fe oxide were synthesized and used in ethylbenzene dehydrogenation to produce styrene. The molybdenum oxide was sup-ported using an u... 相似文献
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Tiago Pinheiro Braga Ant?nio Narcísio Pinheiro Edson R.Leite Regina Cláudia R.dos Santos Antoninho Valentini 《催化学报》2015,(5):712-720
Molybdenum-based catalysts supported on Al2O3 doped with Ni, Cu, or Fe oxide were synthesized and used in ethylbenzene dehydrogenation to produce styrene. The molybdenum oxide was sup-ported using an unconventional route that combined the polymeric precursor method (Pechini) and wet impregnation on commercial alumina. The samples were characterized by X-ray diffraction (XRD), N2 adsorption-desorption isotherms, temperature-programmed reduction of H2 (H2-TPR), and thermogravimetric (TG) analysis. XRD results showed that the added metals were well dis-persed on the alumina support. The addition of the metal oxide (Ni, Cu, or Fe) of 2 wt% by wet im-pregnation did not affect the texture of the support. TPR results indicated a synergistic effect be-tween the dopant and molybdenum oxide. The catalytic tests showed ethylbenzene conversion of 28%–53% and styrene selectivity of 94%–97%, indicating that the addition of the dopant improved the catalytic performance, which was related to the redox mechanism. Molybdenum oxides play a fundamental role in the oxidative dehydrogenation of ethylbenzene to styrene by its redox and acid–base properties. The sample containing Cu showed an atypical result with increasing conver-sion during the reaction, which was due to metal reduction. The Ni-containing solid exhibited the highest amount of carbon deposited, shown by TG analysis after the catalytic test, which explained its lower catalytic stability and selectivity. 相似文献
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Xie Zaiku 《Reaction Kinetics and Catalysis Letters》2005,84(2):247-254
Summary The effects of calcination conditions on the properties of the catalyst for dehydrogenation of ethylbenzene were studied by using TG, DTA, and XRD. The formation temperature of polyferrite was higher than 600°C. The strength of the catalyst changed during calcination. Higher temperature enhanced the strength and improved the activity of catalyst. The calcination model has great influences on the catalyst performance. Multi-stage calcination improved the catalyst activity. 相似文献