Heterogeneously Catalyzed Oxidaion Of Cyclohexane To Cyclohexanol And Cyclohexanone

Selective oxidation of saturated hydrocarbons is of great importance from a fundamental and applied point of view. Because of the high strength and weak polarity of C-H bonds, the C-H bond activation is difficult and alkanes are relatively inert. Moreover, due to the products (oxygen-containing compounds) is active than the raw material (alkane), the deep oxidation to carbon dioxide and water easily occurred. The controlled oxyfunctionalization of alkanes is still one of the major challenges of modern catalysis. In this work, studies on key factors to improve the efficiency of oxidation of cyclohexane to KA oil and development efficient catalyst for the process using molecular oxygen as oxidant in liquid-phase, were carried out.ZG-5, a metal oxide catalyst containing zirconia, was development. This catalyst showed good activity and selectivity for cyclohexane oxidation in mild conditions using air as oxidant. At reaction time of 25 min, 92.8% selectivity to KA oil and 6.4% conversion was obtained; and 14.9% conversion with 83.6% selectivity to KA oil was realized at 50 min.Catalytic oxidation of cyclohexane with molecular oxygen was studied over Co₃O₄ nanocrystals, which was prepared by the method developed in this paper. It showed obviously higher activities as compared to Co₃O₄ prepared by the conventional methods, Co₃O₄/Al₂O₃, or homogeneous cobalt catalyst under comparable reaction conditions.