Фізико-хімічні властивості поверхні VPO-каталізаторів, модифікованих йонами перехідних металів
An influence of the modification with the transition metal ions (Me= Ti, Fe, Zr, Мо, La, W,Ag, Ni ) on physical-chemical properties of VPO-composition surface was studied. VPMeO-samples were investigated by the X-ray phase analysis, X-ray photoelectron spectroscopy, differential thermal analysis and scanning electron microscopy methods. Types of acidic centers were defined by dimethylpyridine and 2,6-dimethylpyridine adsorption. It has been found established that the introduction of the additives and the variation of their concentration (Ме/V=0.05-0.4) in the VPO-matrix do not influences on its composition most has, with the exception of additives Mo, La and Ti. It has been shown that VPO-composition promoted with transitional metal ions modifies its morphology, O1S-electrons binding energy, atomic ratio P/V and the quantity of acidic sites on its surface. It has been found that the change of surface acidic properties of VPMeO-samples by means of additives introduction is characterized by Lewis acidity essentially.