MnTUD-1: synthesis, characterization and catalytic behavior in liquid-phase oxidation of cyclohexane

Manganese containing three dimensional sponge-like amorphous mesoporous silicate MnTUD-1 with Si/Mn ratio of 115, 44 and 25 was prepared by hydrothermal method using tetraethylene glycol as the template. Nitrogen physisorption indicates that MnTUD-1 is a mesoporous material possessing surface area of 430–490 m2/g with mesopore volume of 0.61–0.71 cm3/g and an average adsorption pore diameter of 4.1–4.7 nm. The framework incorporation of manganese was confirmed by FT-IR, EPR and DRS UV–Vis studies. Manganese exists in bivalent and trivalent states in all the materials. MnTUD-1 showed good catalytic activity (13.5% cyclohexane conversion) and high selectivity (84.5%) in the liquid phase oxidation of cyclohexane with tert-butyl hydroperoxide as the oxidant under mild solvent-less reaction conditions.