Preparation, characterization, stability and catalytic reactivity of the 3d transition metals incorporated MCM-41 molecular sieves

摘要

Mesoporous MCM-41 silica was modified by incorporation one or two of 3d transition metal ions (Ti, V, Cr, Mn, Fe, Co, Ni and Cu, ). The mono- and bimetallic mesoporous molecular sieves and their stability (storage under ambient condition over the course of months and under the reaction conditions) were studied by various techniques, such as: XRD, N_2 adsorption-desorption, SEM, TEM, IR spectroscopy and TGA. These modified MCM-41 materials have been shown to be active for the liquid phase oxidation of styrene and benzene with aqueous H_2O_2. It has to note that Ti, V, Cr and bimetallic (V-Ti, Cr-Ni) incorporated catalysts are particularly active both for selective oxidation of styrene and benzene, Mn, V-Ti and V-Co only active for benzene and Co, Cu and V-Cu for styrene. The catalytic results obtained with these 3d transition metals incorporated materials revealed a possible correlation between the catalytic activity and d electron configuration in the valence shell of transition metals.