SELECTIVE GAS PHASE OXIDATION OF MONOCHLOROTOLUENES OVER MODIFIED OXOVANADIUM SYSTEMS SUPPORTED ON Al2O3 AND SiO2

Abstract

V-Mo-O/SiO₂ materials were prepared by the impregnation techniques and characterized by Scanning Electron Microscopy (SEM), FT-IR, Thermal analysis, N₂ adsorption/desorption and X-ray powder diffraction (XRD) to determine the phase structure and loadings of vanadium species. This material was tested for solvent-free catalytic oxidation of monochlorotoluene under chosen conditions. The result shows that V-Mo-O/SiO₂ is effective catalysts, exhibiting conversion of monochlorotoluene and selectivity monochloromaleic anhydride 75–85%, 24–32% respectively. Furthermore, the catalyst can be easily recovered and reused for 20-25 hours without a significant loss in its activity and selectivity. The oxidation rate and direction determined by the temperature (315-450⁰C), proportions between the reagents (1:1–1:15 mol/l), bond dissociation energies, the effects of active components of catalyst and contact time. 

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