Ethylene and acetaldehyde production by selective oxidation of ethanol using mesoporous V-MCM-41 catalysts

Gucbilmez, Yesim
Doğu, Timur
Balci, Suna
Vanadium-incorporated MCM-41 type catalytic materials, which were synthesized by a direct hydrothermal synthesis procedure, showed very high activity and high selectivity in the production of ethylene from ethanol in an oxidative process. Ethylene selectivity showed a significant increase with an increase in temperature over 300 degrees C, while relatively high acetaldehyde selectivities were observed at lower temperatures. An ethylene yield value of 0.66 obtained at 400 degrees C with an O-2/ethanol feed ratio of 0.5 was beneficial from the point of view that these results might open a new pathway for the production of ethylene from a nonpetroleum environmentally friendly feedstock, namely, bioethanol. The optimum V/Si ratio of the catalyst, which gave the maximum ethylene yield, was found to be around 0.04. Experimental results showing the formation of acetaldehyde and not showing the formation of ethylene in the absence of gas-phase oxygen and the catalyst deactivation observed in such conditions suggested a redox mechanism involving the surface lattice oxygen of the catalyst in acetaldehyde production, while the involvement of adsorbed oxygen was concluded to take place in the formation of ethylene.


Partial oxidation of methane on the SiO2 surface - A quantum chemical study
Ozturk, S; Onal, I; Senkan, S (2000-02-01)
Reaction pathways for methane partial oxidation (MPO) on silica were theoretically investigated using the semiempirical MOPAC-PM3 molecular orbital method. The surface of SiO2 was modeled by a helical Si6O18H12 molecular cluster that also exhibits a strained siloxane bridge defect. First, a bond energy analysis was performed on the silica cluster with isolated 3- and 4-coordinated Si surface atoms. Calculated bond dissociation energies for Si-H, SiO-H, and SI-OH were comparable to H-CH3, H-OH, and O-O. In t...
Electrochemical copolymerization of thiophene containing pseudo-polyether cages with pyrrole
Cihaner, Atilla; Önal, Ahmet Muhtar (2006-01-01)
Conducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (1). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution contai...
Enantioselective direct aldol reactions promoted by phosphine oxide aziridinyl phosphonate organocatalysts
Doğan, Özdemir (2015-12-15)
A series of phosphine oxide based chiral Lewis bases were screened as organocatalysts for silicon tetrachloride mediated direct asymmetric aldol reactions between cyclohexanone and various aromatic aldehydes. One of the phosphine oxide-aziridinyl phosphonate POAP-A Lewis bases formed the aldol products in up to 75% yield and with 65% ee.
Polybenzimidazole based nanocomposite membranes with enhanced proton conductivity for high temperature PEM fuel cells
Ozdemir, Yagmur; Uregen, Nurhan; DEVRİM, YILSER (2017-01-26)
In this study, phosphoric acid doped PBI nanocomposite membranes were prepared by dispersion of various amounts of inorganic nanoparticles in PBI polymer followed by phosphoric acid (H3PO4) doping for high temperature proton exchange membrane fuel cells (HT-PEMFC). All of the PBI composite membranes were cast from the same FBI polymer with the same molecular weight. Titanium dioxide (TiO2), silicon dioxide (SiO2) and inorganic proton conductor zirconium phosphate (ZrP) were used as inorganic fillers. The PB...
Heteropolyacid Incorporated Bifunctional Core-Shell Catalysts for Dimethyl Ether Synthesis from Carbon Dioxide/Syngas
Core-shell-type catalysts, which are synthesized by encapsulating the Cu-ZnO-Alumina type methanol synthesis catalyst (CZA) by silicotungstic acid (STA)-incorporated mesoporous alumina, were prepared following a hydrothermal route and tested in DME synthesis from syngas and CO2. Activity tests, which were performed in the pressure range of 30-50 bar, and the temperature range of 200-300 degrees C, with different feed compositions (CO2/CO/H-2: 50/-/50, 40/10/50, 25/25/50, 10/40/50) showed that the best-opera...
Citation Formats
Y. Gucbilmez, T. Doğu, and S. Balci, “Ethylene and acetaldehyde production by selective oxidation of ethanol using mesoporous V-MCM-41 catalysts,” INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, pp. 3496–3502, 2006, Accessed: 00, 2020. [Online]. Available: