Active Sites Characterization in Mixed Vanadium and Iron Antimonate Oxide Catalysts for Propane Ammoxidation

摘要: Abstract Ammoxidation of propane was investigated over FeVSbO mixed oxide catalysts. The results obtained show that in VSbO 4 catalyst systems, substitution vanadium by small quantities iron has a strongly positive effect on the activity With such system, selectivity to acrylonitrile decreases while propene increases. At high levels iron, low but towards enhanced. characterization catalysts carried out using several techniques, as X-ray diffraction, Mossbauer spectroscopy, absorption, and electron microscopy, shown continuous solid solution formed between FeSbO . loading, Fe 3+ substituted for V 4+ cationic-deficient structure 0.64 0.28 Sb 5+ 0.92 ♢ 0.16 O , leading with both cationic anionic vacancies, x 0.33 0.41− 0.18 4− generating very active sites alkane activation. only present bulk solids contributed isolation sites, which are selective acrylonitrile.