Selective Catalytic Oxidation of Benzyl Alcohol and Characterization Studies of Spinel MnAl<SUB>2</SUB>O<SUB>4</SUB> Nanoparticles by a Facile Synthesis Route

Spinel MnAl2O4 nanoparticles were prepared effectively by simplistic, economical microwave heating method (MHM) using Opuntia dillenii extract as reducing agent. The samples were successfully characterized by powder XRD pattern, EDX spectra, FT-IR analysis, HR-SEM analysis, and VSM instrumentation techniques. Powder XRD, EDX and FT-IR results demonstrated that the products contain a pure single-phase spinel structure lacking of other secondary phase impurities. HR-SEM results confirmed the spherical shaped nanoparticle morphology of the sample. Magnetic characterization property was confirmed by VSM analysis. VSM hysteresis loop established the superparamagnetism of the sample and the magnetization (Ms value of MnAl2O4 is 0.023 emu/g. It was found that MnAl2O4 nanoparticle is highly active towards the selective oxidation of benzyl alcohol into benzaldehyde at a low temperature with very high yield, due to the higher surface area and number of active sites.