Cu and Fe modified Cerium and Zirconium Oxides for the Oxidation of Cyclohexane to KA Oil

Abstract

Ce and Zr oxides have been tested in the oxidation of cyclohexane to KA oil because of the possibility to tune their crystal structure and redox properties by introducing defects, and of modifying their mechanical and thermal stability. The redox properties of the two oxides, prepared by the inverse microemulsion technique, have been tuned by homogeneously including Cu or Fe (10 % molar) into their structures. These modifications led to very different behaviours in terms of both KA oil productivity and K/A ratios, especially upon undergoing reduction treatment, being the reduced Cu-modified CeO2 oxide the most active catalyst, able to produce 2.2 mmol of KA oil after 5 hours with 93.2 % selectivity (K/A 2.6). The materials obtained have been characterized by solid state analytical techniques to study their structure, morphologies as well as their bulk and surface chemistry (STEM/EDX, BET, XRD, XPS).