Catalytic oxidation of benzene over Ce–Mn oxides synthesized by flame spray pyrolysis--颗粒学报PARTICUOLOGY

Liu, G., Yue, R., Jia, Y., Ni, Y., Yang, J., Liu, H., Wang, Z., Wu, X., & Chen, Y. (2013). Catalytic oxidation of benzene over Ce–Mn oxides synthesized by flame spray pyrolysis. Particuology, 11(4), 454–459. https://doi.org/10.1016/j.partic.2012.09.013

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

Gang Liu ^{a b}, Renliang Yue ^a, Yi Jia ^{a b}, Yong Ni ^a, Jie Yang ^a, Haidi Liu ^a, Zhen Wang ^{a b}, Xiaofeng Wu ^a, Yunfa Chen ^a *

a State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
b Graduate University of Chinese Academy of Sciences, Beijing 100049, China

10.1016/j.partic.2012.09.013

Volume 11, Issue 4, August 2013, Pages 454-459

Available online 9 May 2013.

E-mail: yfchen@home.ipe.ac.cn

Highlights

• Ce–Mn oxides for catalytic oxidation of benzene were synthesized by flame spray pyrolysis (FSP).

• Ce–Mn oxides of size <40 nm and specific surface areas of 20–50 m²/g were formed with different Ce–Mn ratios.

• Relative lower benzene conversion temperature (T₉₅ ≈ 260 °C) was achieved by 12.5%-Ce–Mn oxides.

• Better activity was attracted to the synergetic effect of Ce and Mn and small particle sizes as well.

Abstract

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), N₂ adsorption, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Raman spectroscopy, and H₂-temperature programmed reduction (H₂-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 20–50 m²/g. Raman spectrums and H₂-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 cerium-to-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.

Graphical abstract

Keywords

Flame spray pyrolysis; Catalytic oxidation; VOCs; Ce–Mn oxide

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