铋改性的钒磷氧化物液相催化氧化环己烷的反应机理

 制备了铋改性的钒磷氧化物(Bi-VPO)催化剂,并将其用于液相催化氧化环己烷,研究了该反应的反应机理. 结果表明,铋改性可大大提高VPO催化剂在温和条件下对环己烷液相氧化的催化性能. 无溶剂实验和四氢呋喃作溶剂的实验证明反应过程中溶剂乙腈和H2O2之间存在相互作用; 自由基捕捉实验证明环己烷氧化过程中存在自由基反应历程; 环己醇氧化实验证明环己酮并不是来自环己醇的氧化,而是由环己烷直接氧化得到的.

Reaction Mechanism of Liquid-Phase Oxidation of Cyclohexane Catalyzed by Bi-Modified Vanadium-Phosphorous Oxide Catalyst

Bi-modified vanadium-phosphorous oxide(Bi-VPO) catalysts were prepared and used in liquid-phase oxidation of cyclohexane.The results showed that Bi modification could greatly enhance the catalytic performance of Bi-VPO for the oxidation of cyclohexane under mild conditions.The experiments without any solvent and with tetrahydrofuran as a solvent indicated the existence of interaction between acetonitrile and hydrogen peroxide.The free radical trap experiment proved that a free radical process is present in the catalytic system.The oxidation experiment of cyclohexanol explained that cyclohexanone is derived directly from cyclohexane oxidation instead of cyclohexanol oxidation.