Oxidation of cyclohexane catalyzed by metal-containing ZSM-5 in ionic liquid

Metal-containing ZSM-5 (MZSM-5) molecular sieves were prepared and characterized by XRD, EDX, SEM and N2-physisorption. The prepared MZSM-5 catalysts were found to be very effective for cyclohexane oxidation with tert-butyl-hydroperoxide in ionic liquid [emim]BF4 under mild conditions. Good yields and high selectivity of products were found in the ionic liquid compared within molecular solvent. The catalytic activity of FeZSM-5 was superior to that of other MZSM-5 and the as-received HZSM-5 in ionic liquid. For cyclohexane oxidation catalyzed by FeZSM-5, 20.9% conversion of cyclohexane and 98.2% selectivity of desired products were obtained in ionic liquid at the temperature of 90 °C. The catalyst/ionic liquid system could be successfully recycled by a simple decantation procedure without significant loss of activity.

A convenient and efficient application of tert-butyl hydroperoxide/metal-containing ZSM-5 in ionic liquids [emim]BF4 for the oxidation of cyclohexane to cyclohexanone and cyclohexanol is described. As shown in the below table, good yields and higher selectivity of products were obtained in ionic liquid compared with in molecular solvent. The catalytic activity of FeZSM-5 was superior to that of other MZSM-5 and the as-received HZSM-5 in ionic liquid. For cyclohexane oxidation catalyzed by FeZSM-5, 20.9% conversion of cyclohexane and 98.2% selectivity of desired products were obtained in ionic liquid. The catalyst/ionic liquid system could be successfully recycled by a simple decantation procedure without significant loss of activity. Figure optionsDownload as PowerPoint slide