Coherent-Synchronized Biomimetic Monooxidation of Cyclohexane by Hydrogen Peroxide

Abstract

Activity and selectivity of heterogeneous biomimetic catalysts per-FTPhPFe(III)OH/Al₂O₃ and PPFе(III)OH/Al₂O₃ towards particular compound have been studied during the process of gas-phase oxidation of cyclohexane and its mixture. Varying process parameters (temperature, H₂O₂ concentration, contact time) has provided an opportunity to obtain a common understanding of the active influence of these catalysts during the oxidation of cyclohexane in the mixture with its derivatives, where their selective action towards cyclohexane has also been observed. On the basis of the experimental research of the process of cyclohexane monooxidation, it has been found out that a complex reaction takes place on the biomimetic catalyst. This complex reaction consists of parallel-sequential monooxidation and oxidative dehydrogenation reactions that are coherently synchronized with H₂O₂ decomposition reaction. Possible mechanisms of cyclohexane biomimetic conversion to the target products are presented. The unity of the mechanisms of acid-base catalysis and the redox system based on the principle of CBR (chain of bond rearrangement) which is typical of enzymatic catalysis can be traced during this conversion. Depending on the process parameters, it is possible to consciously control the direction of the monooxidation reaction and its rate.