Activity Comparison of MCM-41 and V-MCM-4 Catalysts for Ethanol Selective Oxidation and DRIFTS Analysis

Gucbilmez, Yesim
Doğu, Timur
The activity of a V-MCM-41 catalyst with a V/Si molar ratio of 0.04 was compared with the activity of a pure MCM-41 catalyst and some DRIFTS studies were performed in order to understand the mechanism of selective oxidation of ethanol. V-MCM-41 was found to be much more active than pure MCM-41, favouring the formation of high amounts of ethylene over 300 degrees C. MCM-41, on the other hand, was found to favour the formation of acetaldehyde over ethylene at all studied temperatures. It was shown by reaction findings that over V-MCM-41, ethylene was produced mainly in the presence of gas phase oxygen whereas acetaldehyde was produced using the lattice oxygen even in the absence of gas phase oxygen. DRIFTS studies indicated the formation of acetaldehyde molecules from acetate-like surface species which were formed by the removal of a hydrogen atom from the beta-carbon of chemisorbed ethoxy species by the help of the lattice oxygen. On the other hand, removal of a hydrogen atom from the beta-carbon of the ethoxy species, in the presence of gas phase oxygen, resulted in the formation of vinyl-like surface species which then yielded ethylene molecules.


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Demir-Kıvrak, Hilal; Üner, Deniz; Kuliyev, Sadig; Department of Chemical Engineering (2010)
In this study, the role of defects, the role of Sn in relation to defects, and the role of oxide phase of tin in ethanol electro-oxidation reaction were investigated. Firstly, adsorption calorimetry measurements were conducted on monometallic (1%Pt, 2%Pt, and 5%Pt) and bi-metallic (5% Pt-Sn) γ-Al2O3 supported Pt catalysts. It was observed that while saturation coverage values decreased, intermediate heats remained same for Pt-Sn catalysts by the increasing amount of tin. The effect of particle size was inve...
Citation Formats
Y. Gucbilmez, T. Doğu, and F. S. BALCI, “Activity Comparison of MCM-41 and V-MCM-4 Catalysts for Ethanol Selective Oxidation and DRIFTS Analysis,” INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING, pp. 0–0, 2009, Accessed: 00, 2020. [Online]. Available: