Oxidative dehydrogenation of but-1-ene with lattice oxygen in ferrite catalysts

Abstract

The oxidative dehydrogenation (ODH) of but-1-ene was carried out using the lattice oxygen in ferrite catalysts in the temperature range of 200–300°C with a fixed-bed flow reactor at atmospheric pressure. Various ferrite catalysts, such as NiFe2O4/AC-500, ZnFe2O4/AC-500, CoFe2O4/AC-500, and CuFe2O4/AC-500, -400, -300, -280, were prepared in the presence of activated carbon in the calcination temperature range of 280–500°C. When but-1-ene-TPR was measured using various ferrite catalysts, CuFe2O4/AC-500 progressed the ODH of but-1-ene at 200–300°C. Among the catalysts, CuFe2O4/AC-500 showed the highest Buta-1,3-diene (BD) yield, at 270°C. XRD and XPS analyses of the catalyst after the ODH suggested that the lattice oxygen in Cu-O bonded to the tetrahedral site (Cu2+T) of the ferrite structure was used for the ODH. In addition, the used catalyst was recovered by re-oxidation with molecular O2. Moreover, CuFe2O4/AC-280, which calcined at 280°C, had the highest specific surface area and improved the BD yield with an increase in contact area with but-1-ene. In the repeated ODH (reaction and regeneration cycle), CuFe2O4/AC-500 and -280 catalysts maintained BD yields of 7.5% and 11.3%, respectively. BD production is thought to be related to the amount of Cu2+T.