Abstract:
Cyclohexanone, a widely used organic chemical raw material, plays a very important role in industrial production. Hydrogenation of phenol to cyclohexanone has the advantages of mild reaction conditions, few by-products, and environmental friendliness. Pd/C catalyst was used for the hydrogenation of phenol to cyclohexanone. After comparing the dichloromethane, cyclohexane, ethanol, and benzene, benzene was selected as the solvent. At the reaction temperature 160—250 ℃, the reaction pressure 0.1—2.0 MPa, the weight hourly space velocity of phenol 0.2—1.0 h
−1, the molar ratio of hydrogen to phenol 2—12, the influence of reaction conditions on the hydrogenation of phenol was investigated. A fixed bed tubular reactor charged with 80—100 mesh(150—180 μm)Pd/C catalyst was developed. Eliminating the influence of internal and external diffusion, 25 groups of experimental data were measured by changing the temperature, pressure and molar ratio of hydrogen to phenol. An intrinsic kinetic model was established based on the ideal adsorption model. The optimal reaction parameters were determined using 25 sets of orthogonal experimental data, and the dynamics model was also examined. The results show that the suitable reaction conditions are as follows: reaction temperature 175—205 ℃, reaction pressure 0.1 MPa, the molar ratio of hydrogen to phenol about 4, and the weight hourly space velocity of phenol 0.2—0.4 h
−1. After statistical test and residual analysis, the established intrinsic kinetic model is applicable and has good reliability.