Oxidative Dehydrogenation of Cyclohexane to Cyclohexene over Mg-V-O Catalysts
Oxidative Dehydrogenation of Cyclohexane to Cyclohexene over Mg-V-O Catalysts
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DOI：
10.1007/s10562-009-0064-2
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发表时间：
2009-08-01
影响因子：
2.8
通讯作者：
Cheng, Zhen-Min
中科院分区：
文献类型：
--
作者：
Jin, Mei;Cheng, Zhen-Min
研究了不同Mg/V原子比的Mg-V-O催化剂上环己烷氧化脱氢反应。采用柠檬酸络合法制备了催化剂，并用N2吸附、XRD、FT-IR、拉曼光谱、NH3-TPD和H2-TPR等技术对催化剂进行了表征。在纯钒酸镁中，Mg-3（VO 4）（2）具有孤立的活性中心、弱碱性表面和较低的金属阳离子还原性，可作为催化剂的活性相。此外，还研究了一系列机械混合催化剂在该反应中的协同效应。结果表明，Mg-3（VO 4）（2）与适量MgO和Mg 2 V2 O 7混合后，由于MgO固溶于Mg-3（VO 4）（2）相中，以及遥控机制，在转化率、产率和选择性方面均表现出协同效应。在两相催化剂中，（7/4）MgVO催化剂表现出较好的催化性能，环己烷转化率为13.9%，环己烯选择性为45.7%。
The oxidative dehydrogenation of cyclohexane was studied over Mg-V-O catalysts with different Mg/V atomic ratios. Catalysts were prepared via citric acid complexation and characterized by N-2-adsorption, XRD, FT-IR, Raman spectroscopy, NH3-TPD and H-2-TPR techniques. Among the pure magnesium vanadates, Mg-3(VO4)(2) has the isolated active sites, weakly basic surface and lower reducibility of the metal cations, and could be recognized as the catalytic active phase. Furthermore, a series of mechanically mixed catalysts were studied in the reaction in attempting to investigate the synergetic effect. The finding revealed synergetic effects in the conversion, in the yield, and in the selectivity were observed in Mg-3(VO4)(2) mixing with a suitable amount of MgO and Mg2V2O7 due to a solid solution of MgO in the Mg-3(VO4)(2) phase and the remote control mechanism, respectively. Among the biphasic catalysts, (7/4)MgVO catalyst exhibited a better catalytic performance, on which a cyclohexene selectivity of 45.7% at cyclohexane conversion of 13.9% was obtained.