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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Karakaş, Gürkan (2019-02-15)
The high temperature catalytic oxidation (HTCO) performance of Al2O3 supported Pt, Cu, Cu-Ce and Fe catalysts were systematically studied with a perspective of selective oxidation of nitrogenous compounds to nitric oxide for quantitative determination of bound nitrogen. The catalyst samples were prepared via impregnation and characterized by XRD and BET. In addition, temperature programmed reaction experiments with acetonitrile and oxygen were conducted to evaluate the catalytic activity and selectivity tow...
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Öztürk, Zafer; Gökağaç Arslan, Gülsün; Department of Chemistry (2011)
In this work, two groups of carbon supported Pt-Pd catalysts have been prepared in order to investigate the effect of Pd, as a second metal, and surfactants on the catalytic activity towards methanol and ethanol oxidation reactions used in the direct methanol and ethanol fuel cells. In the first group (group a), 1- hexanethiol was used as a stabilizing agent while in the second group (group b), 1,1 dimethyl hexanethiol was utilized. Cyclic voltammetry (CV), chronoamperometry (CA), X-ray diffraction (XRD), t...
Sulfated zirconia in SBA-15 structures with strong Bronsted acidity as observed by H-1 MAS NMR spectroscopy
Yılmaz, Ayşen; Yılmaz, Aysun; Üner, Deniz (2007-05-01)
In order to prepare high surface area highly acidic catalysts, different weight loadings of ZrO2 were incorporated in the SBA-15 structures which are subsequently sulfated by treating in 0.25 M H2SO4. The catalysts were characterized by means of TEM, XRD, N-2 adsorption, and H-1 MAS NMR. Bronsted type acidities of sulfated zirconia included SBA-15 materials were identified by a sharp H-1 MAS NMR line at 10.6 ppm. The highest acidity was obtained in the 25 mol% ZrO2 included SBA-15 catalyst with a BET surfac...
Activity Comparison of Different Solid Acid Catalysts in Etherification of Glycerol with tert-Butyl Alcohol in Flow and Batch Reactors
Ozbay, Nalan; OKTAR, NURAY; DOĞU, GÜLŞEN; Doğu, Timur (2013-12-01)
In the presented work, etherification of glycerol with TBA was investigated in a continuous flow and also in a batch reactor using nine different commercial solid acid catalysts, namely Amberlyst-15, Amberlyst-36, Amberlyst-35, Amberlyst-16, Relite EXC8D, Lewatit K2629, H-Beta, H-Mordenite and Nafion SAC-13. Results proved the advantages of flow reactor to achieve quite high glycerol conversion values in very short residence times, due to efficient contact of reactants with the solid catalyst, which was cau...
Synthesis and characterization of ethanol electro-oxidation catalysts
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: