The ultrafine V 2O 5 TiO 2 composite oxide particles have been prepared by the high energy ball milling method and characterized by X ray diffraction, transmission electron microscopy, laser Raman spectroscopy, temper...The ultrafine V 2O 5 TiO 2 composite oxide particles have been prepared by the high energy ball milling method and characterized by X ray diffraction, transmission electron microscopy, laser Raman spectroscopy, temperature programmed reduction, and microreactor testing. It has been shown that the milling process induces the formation of ultrafine V 2O 5 TiO 2 composite oxide particles with dispersed vanadium oxide on the surface of anatase TiO 2, accompanied by a decrease in particle size of V 2O 5 and TiO 2. The TPR results indicate that the strong interaction between dispersed V O species and TiO 2 increases the reducibility of the vanadium oxide. The catalytic properties of the catalysts for the selective oxidation of o xylene were evaluated. Under the similar o xylene conversion (58%), the ultrafine V 2O 5 TiO 2 composite oxide catalyst exhibits a higher selectivity for phthalic anhydride (44%) than the catalyst prepared by the conventional impregnation method (23%), and the catalyst composition has a great influence on the catalytic properties.展开更多
文摘The ultrafine V 2O 5 TiO 2 composite oxide particles have been prepared by the high energy ball milling method and characterized by X ray diffraction, transmission electron microscopy, laser Raman spectroscopy, temperature programmed reduction, and microreactor testing. It has been shown that the milling process induces the formation of ultrafine V 2O 5 TiO 2 composite oxide particles with dispersed vanadium oxide on the surface of anatase TiO 2, accompanied by a decrease in particle size of V 2O 5 and TiO 2. The TPR results indicate that the strong interaction between dispersed V O species and TiO 2 increases the reducibility of the vanadium oxide. The catalytic properties of the catalysts for the selective oxidation of o xylene were evaluated. Under the similar o xylene conversion (58%), the ultrafine V 2O 5 TiO 2 composite oxide catalyst exhibits a higher selectivity for phthalic anhydride (44%) than the catalyst prepared by the conventional impregnation method (23%), and the catalyst composition has a great influence on the catalytic properties.
