Highly Efficient Epoxidation of Cyclopentene Catalyzed by Magnetically Recoverable Mg–doped Cobalt Ferrites with Greatly Improved Performances

Abstract The alkaline earth metal Mg-doped CoFe2O4 composite ferrite samples MgxCo1-xFe2O4 (x=0, 0.1, 0.3, 0.5, 0.7 and 1) were prepared using a sol-gel auto-combustion route. The as-prepared samples were characterized by Raman spectrometry, X-ray diffractometry (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), ICP?atomic emission spectroscopy and N2-physisorption. The catalytic activities of the samples were tested in the cyclopentene oxidation using hydrogen peroxide (30?%) as the oxidant. Compared with the pristine CoFe2O4 and MgFe2O4, the Mg?Co composite ferrites showed much enhanced catalytic performances in the oxidation of cyclopentene with cyclopentene oxide as the main product. In particular, 95.2?% of cyclopentene conversion and 96.3?% of selectivity for cyclopentene oxide were achieved when Mg0.5Co0.5Fe2O4 was used at 60 oC for 8?h in the oxidation reaction. The catalyst can be easily separated by applying magnetic field and exhibits great reusability.