Journal of Molecular Catalysis A-Chemical, Vol.387, 31-37, 2014
Highly efficient catalytic oxidation of cyclohexanol with TBHP over Cr-13X catalysts in a solvent-free system
With respect to the consideration of environment and economy, simple, inexpensive, and reusable solid catalysts have been attracting much attention. In this work, a series of non-noble transition-metal ion-exchanged zeolite catalysts have been prepared and applied in the catalytic oxidation of cyclohexanol and other alcohols with tert-butyl hydroperoxide (TBHP) to aldehydes or ketones in the absence of any solvent and additive. Among various catalysts tested, Cr3+-exchanged 13X has exhibited the best activity with the highest efficiency of TBHP utilization, and been proven to be a recyclable heterogeneous catalyst for the oxidation of cyclohexanol with TBHP. The effects of the Cr loading, the reaction temperature, the reaction time, and the cyclohexanol/TBHP molar ratio have been investigated systematically. Furthermore, a feasible oxidation route is proposed. (C) 2014 Elsevier B.V. All rights reserved.