Synthesis of porous NiFe2O4 microparticles and its catalytic properties for methane combustion

In this paper, we report the obtention of agglomerate porous NiFe2O4 microparticles type-spinel with uniform size of 1-2 mu m by the oxalic acid co-precipitation method.The structure, morphology and surface of microparticles as-synthesized were characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), respectively. Fixed bed reactor test confirmed that the NiFe2O4 microparticles exhibit a good catalytic activity for methane combustion with the methane light-off temperature below 350 degrees C. XPS spectrum revealed that the excellent catalytic activity may be attributed to the surface oxygen vacancies arising from the peculiar inverse spinel structure with octahedral (Oh) site occupied by Fe2+ and Ni2+ cations. (C) 2011 Elsevier B.V. All rights reserved.