Identification of active phase for selective oxidation of benzyl alcohol with molecular oxygen catalyzed by copper-manganese oxide nanoparticles

Catalytic activity of copper-manganese mixed oxide nanoparticles (cu/mn = 1: 2) prepared by coprecipitation method has been studied for selective oxidation of benzyl alcohol using molecular oxygen as an oxidizing agent. the copper-manganese (cumn 2) oxide catalyst exhibited high specific activity of 15.04 mmolg -1 h -1 in oxidation of benzyl alcohol in toluene as solvent. a 100 conversion of the benzyl alcohol was achieved with >99% selectivity to benzaldehyde within a short reaction period at 102°c. it was found that the catalytic performance is dependent on calcination temperature,and best activity was obtained for the catalyst calcined at 300°c. the high catalytic performance of the catalyst can be attributed to the formation of active mno 2 phase or absence of less active mn 2o 3 phase in the mixed cumn 2 oxide. the catalyst has been characterized by powder x-ray diffraction (xrd),thermogravimetric analysis (tga),scanning electron microscopy (sem),transmission electron microscopy (tem),brunauer emmett-teller (bet) surface area measurement,and fourier transform infrared (ft-ir) spectroscopies. © 2013 roushown ali et al.