Catalytic oxidation of benzene over Ce-Mn oxides synthesized by flame spray pyrolysis

Flame spray pyrolysis(FSP) was utilized to synthesize Ce-Mn oxides in one step for catalytic oxidation of benzene.Cerium acetate and manganese acetate were used as precursors.The materials synthesized were characterized using X-ray diffraction(XRD),Nadsorption,X-ray photoelectron spectroscopy(XPS).transmission electron microscopy(TEM),Raman spectroscopy,and Fh-temperature programmed reduction(H-TPR) and their benzene catalytic oxidation behavior was evaluated.Mn ions were evidenced in multiple chemical states.Crystalline Ce-Mn oxides consist of particles with size <40 nm and specific surface areas(SSA) of 20-50m~2/g.Raman spectrums and H-TPR results indicated the interaction between cerium and manganese oxides.Flame-made 12.5%-Ce-Mn oxide exhibited excellent catalytic activity at relatively low temperatures(T95 about 260 C) compared to other Ce-Mn oxides with different ceriumto-manganese ratios.Redox mechanism and strong interaction conform to structure analysis that Ce-Mn strong interaction formed during the high temperature flame process and the results were used to explain catalytic oxidation of benzene.