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论文类型：期刊论文

发表时间：2010-12-22

发表刊物：CATALYSIS TODAY

收录刊物：SCIE、Scopus

卷号：158

期号：3-4

页面范围：464-469

ISSN号：0920-5861

关键字：Ethylbenzene; Oxidative dehydrogenation; Carbon dioxide; Iron oxide-based catalysts

摘要：This paper describes dehydrogenation reaction of ethylbenzene to styrene with CO(2) over iron oxide-based catalysts. Three catalysts of Fe(2)O(3)-MgO/gamma-Al(2)O(3), Fe(2)O(3)/MgAl(2)O(4) and MgFe(0.1)Al(1.9)O(4) with the same molar ratio of Mg/Fe/Al were prepared by impregnation and sol-gel methods. At 580 degrees C, the ethylbenzene conversion over MgFe(0.1)Al(1.9)O(4) kept a value of 40% during the time on stream of 20 h, whereas that over Fe(2)O(3)/MgAl(2)O(4) decreased rapidly from initial 50.0% to 27.4%. The properties of the catalysts were characterized by several techniques such as N(2) adsorption/desorption, X-ray diffraction, thermogravimetry, energy dispersive X-ray spectroscopy, Fourier transform-infrared spectroscopy, (57)Fe Mossbauer spectroscopy, temperature-programmed reduction, and temperature-programmed desorption of NH(3) and CO(2). It was found that the iron species of these catalysts are different. In MgFe(0.1)Al(1.9)O(4), all Fe(3+) species are incorporated in the spinel lattice. MgFe(0.1)Al(1.9)O(4) shows high catalytic activity and stability in ethylbenzene dehydrogenation reaction with CO(2). Moreover, the weak surface acidity of MgFe(0.1)Al(1.9)O(4) prevents from the carbon formation during the reaction. (C) 2010 Elsevier B.V. All rights reserved.