Nano-structured β-MgMoO4 : Synthesis, Characterization and Catalytic Efficiency in the 3- Nitrophenol Reduction

Abstract

A monoclinic magnesium molybdate, MgMoO₄, was synthesized via the thermal decomposition at 500 °C of an oxalate precursor that was prepared by grinding and heating at 160 °C a solid state mixture of magnesium nitrate, ammonium molybdate and oxalic acid. The precursor was characterized by thermal gravimetric analysis (TGA), and the final obtained powders were studied by X-ray diffraction (XRD), N₂ adsorption desorption (BET), and Transmission Electron Microscopy (TEM). The results are consistent with the formation of β-MgMoO₄ agglomerated spherical nanoparticles, with an average crystallite size of 40 nm, 36 nm and 76 nm obtained from TEM, XRD and BET, respectively. The β-MgMoO₄ nanoparticles were applied as catalysts in the reduction of 3-Nitrophenol to 3-Aminophenol and the rate constant of the reaction was subsequently determined as 3.1x 10^-2 min^-1