Improvement of catalytic activity in selective oxidation of styrene with H2O2 over spinel Mg–Cu ferrite hollow spheres in water

• Uniform spinel ferrite hollow spheres were prepared by a simple method.
• The catalyst has been proved much more efficient for styrene oxidation than the reported analogues.
• The catalyst can be easily separated by external magnetic field and has exhibited excellent reusability.
• The catalytic system is environmentally friendly.

Uniform spinel Mg–Cu ferrite hollow spheres were prepared using carbon spheres as templates. For comparison, solid Mg–Cu ferrite nanocrystals were also prepared by sol–gel auto-combustion, hydrothermal and coprecipitation methods. All the samples were characterized by Fourier transform infrared spectrophotometry (FT-IR), X-ray diffractometry (XRD), transmission electron microscopy (TEM) and N2 physisorption. The samples were found to be efficient catalysts for oxidation of styrene using hydrogen peroxide as oxidant. Especially, in the case of Mg0.5Cu0.5Fe2O4 hollow spheres, obvious improvement on catalytic activity was observed, and 21.2% of styrene conversion and 75.2% of selectivity for benzaldehyde were obtained at 80 °C for 6 h reaction in water. The catalyst can be magnetically separated easily for reuse and no obvious loss of activity was observed when reused in six consecutive runs.

Uniform spinel Mg–Cu ferrite hollow spheres were prepared using carbon spheres as templates. Solid spinel Mg0.5Cu0.5Fe2O4 ferrite nanocrystals were also prepared by sol–gel auto-combustion, hydrothermal and coprecipitation methods for comparison. The samples were found to be efficient catalysts for oxidation of styrene using hydrogen peroxide as oxidant. Especially, in the case of Mg0.5Cu0.5Fe2O4 hollow spheres, obvious improvement on catalytic activity was observed and 21.2% of styrene conversion and 75.2% of selectivity for benzaldehyde were obtained at 80 °C for 6 h reaction in water. The catalyst can be magnetically separated easily for reuse and no obvious loss of activity was observed when reused in six consecutive runs.Figure optionsDownload as PowerPoint slide