초록 |
Vanadium oxide catalyst supported on TiO2-ZrO2 has been prepared by adding Ti(OH)4-Zr(OH)4 powder to an aqueous solution ammonium metavanadate followed by drying and calcining at high temperatures. The characterization of the prepared catalysts was performed using FTIR, 51V NMR and catalytic activity. In the case of clacination temperature at 773 K, vanadium oxide was in a highly dispersed state for the samples containing low loading V2O5 below 25 wt% but for samples containing high loading V2O5 equal to or above 25 wt%, vanadium oxide was well crystallized due to the V2O5 loading exceeding the formation of monolayer on the surface of TiO2-ZrO2. The ZrV2O7 compund was formed through the reaction of V2O5 and ZrO2 at 773 - 973 K, whereas the V3Ti6O17 compound was formed through the reaction of V2O5 and TiO2 at 973 - 1073 K. The V3Ti6O17 compound decomposed to V2O5 and TiO2 at 1173 K, which were confirmed by FTIR, 51V NMR and XRD. |