NONOXIDATIVE DEHYDROGENATION OF CYCLOHEXANOL OVER COPPER IRON BINARY OXIDES

The catalytic behavior of copper-iron binary oxides in the nonoxidative dehydrogenation of cyclohexanol was studied. Catalyst characterization was carried out by means of X-ray diffraction (XRD), Mossbauer spectroscopy, temperature-programmed desorption (TPD) and BET surface area measurements. It was observed that dehydrogenation of cyclohexanol to cyclohexanone proceeds mainly on reduced metallic copper. The yield of cyclohexanone reached a level as high as 79% on Cu-Fe3O4 at 663 K, much higher than that on Cu-ZnO (ca. 56%). As regards the dehydration side reaction, it seemed that cyclohexene was formed on the acidic sites resulting from the partial occupation of octahedral sites in the magnetite structure by Cu2+ ions. On the other hand, the dehydrogenation of cyclohexanol to phenol appeared to occur on the surface of Fe3O4.