Oxidative dehydrogenation of n-butenes to 1,3-butadiene over BiMoFe_0.65P_x catalysts: effect of phosphorous contents

摘要

A series of BiMoFe_0.65P _x oxide catalysts with varying phosphorous contents from 0.0 to 0.6 mol ratio were prepared by a co-precipitation method, and oxidative dehydrogenation (ODH) was carried out to produce 1,3-butadiene (BD) from n-butenes. The physico-chemical properties of the oxide catalysts were characterized by X-ray diffraction (XRD), Raman spectroscopy, N₂ sorption, and NH₃ and 1-butene temperature-programmed desorption (TPD). Among the catalysts studied here, BiMoFe_0.65P_0.1 oxide catalyst showed the highest conversion and selectivity to BD. From the result of 1-butene TPD, the higher catalytic activity is related to the amount of weakly bounded intermediate and the desorbing temperature of strongly bounded intermediates. Also, the higher catalytic activity likely originates from the acidity of the BiMoFe_0.65P_0.1 oxide catalyst; its acidity was higher than that of phosphorous-free oxide catalyst and further contained other oxide catalysts. BiMoFe_0.65P_0.1 oxide catalyst is stable and no significant deactivation for 100 h ODH reaction was shown.