Fe-MCM-41 with highly ordered mesoporous structure and high Fe content: synthesis and application in heterogeneous catalytic wet oxidation of phenol

Abstract

Iron-substituted MCM-41 materials (Fe-MCM-41) have been synthesized via a hydrothermal method with in situ incorporation of Fe(III) oxalate complex under various basic conditions. The resulting Fe-MCM-41 samples were characterized by X-ray diffraction, N-2 adsorption measurement, and UV-Vis spectrometry. By controlling initial synthesized pH, the Fe-MCM-41 with highly ordered hexagonal mesoporous structures and high iron content (Si/Fe = 20) could be obtained. The iron species in Fe-MCM-41 samples mainly coexisted in isolated iron and highly dispersed iron oxide nanoclusters. Activity and stability of the obtained catalyst were evaluated on the wet peroxide oxidation of phenol under mild reaction conditions (< 80 A degrees C, ambient pressure). The Fe-MCM-41 with highly ordered mesoporous structure and high Fe content appeared to be the most interesting catalysts for phenol degradation owing to its high organic mineralization, low sensitivity to leaching Fe out and good oxidant efficiency.