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Publikace detail

Conversion of ethanol to acetaldehyde over VOX-SiO2 catalysts: the effects of support texture and vanadium speciation
Autoři: Čičmanec Pavel | Raabová Kateřina | Hidalgo J. M. | Kubička David | Bulánek Roman
Rok: 2017
Druh publikace: článek v odborném periodiku
Název zdroje: Reaction Kinetics Mechanisms and Catalysis
Název nakladatele: Springer
Místo vydání: Heidelberg
Strana od-do: 353-369
Tituly:
Jazyk Název Abstrakt Klíčová slova
cze Konverze etanolu na acetaldehyd na VOx-SiO2 katalyzátorech: vliv textury nosiče a druhů vanadu Vanadové katalyzátory na nosičích SBA-15 a pyrogenické silice byly připraveny impregnací, aby jejich obsah vanadu byl 1, 5 a 10 hmot. %. Katalyzátory byly charakterizovány metodami XRF, N2-BET, SEM, H2-TPR, DR UV-VIS a Ramanova spektroskopie s cílem stanovit druhy vanadu přítomné v těchto katalyzátorech. Dále byly testovány v oxidaci etanolu kyslíkem při 250 a 300 °C. oxidace etanolu; acetaldehyd; oxid vanadu; silika; SBA-15
eng Conversion of ethanol to acetaldehyde over VOX-SiO2 catalysts: the effects of support texture and vanadium speciation SBA-15 and fumed-silica-supported vanadium catalysts prepared by impregnation to contain 1, 5 and 10 wt% of vanadia were characterized by XRF, N-2-BET, SEM, H-2-TPR, DR UV-vis and Raman spectroscopy to determine the key vanadium species present in these catalysts. These catalysts were then used in the oxidation of ethanol by oxygen at 250 and 300 degrees C. The comparison of the catalytic performances of individual catalysts with their physico-chemical characteristics led to the conclusion that oligomeric tetrahedrally coordinated vanadium species have the highest potential for the selective oxidation of ethanol reaching high intrinsic catalytic activity and high selectivity to acetaldehyde. They differ significantly from catalysts with a high population of monomeric species, which exhibit low activity, especially at 250 degrees C, and high selectivity to ethylene as a product of ethanol dehydration. The observed changes in the isothermal dependence of selectivity to ethene on the conversion degree were ascribed to the auto-inhibition effect of water vapor. Ethanol oxidation; Acetaldehyde; Vanadium oxide; Silica; SBA-15