Abstract: Cyclohexanol is a commonly used organic compound. Currently, the most promising industrial process for synthesizing cyclohexanol, by cyclohexene hydration, suffers from a low conversion rate and difficult separation. In this paper, a three-column process for catalytic distillation applicable in the hydration of cyclohexene to cyclohexanol was established to solve these. Simulation with Aspen Plus shows that the process has good advantages, the conversion of cyclohexene reached 99.3%, and the product purity was ≥99.2%. The stable operation of the distillation system requires a good control scheme. The design of the control scheme is very important. However, at present, the reactive distillation process for cyclohexene hydration is under investigation experimentally and by steady-state simulation. Therefore, three different plant-wide control schemes were established (CS1, CS2, CS3) and the position of temperature sensitive stage was selected by using sensitivity analysis method and singular value decomposition method. The Tyreus-Luyben empirical tuning method was used to tune the controller parameters. Finally, Aspen Dynamics simulation software was used to evaluate the performance of the three control schemes. By introducing ΔF ±20% and x_ENE ±5%, comparison the changes in product purity and yield of the three different control schemes. By comparison, we can see that the control scheme CS3 has the best performance.

Key words: Cyclohexene hydration, Catalytic distillation, Control schemes, Dynamic Simulation

摘要： Cyclohexanol is a commonly used organic compound. Currently, the most promising industrial process for synthesizing cyclohexanol, by cyclohexene hydration, suffers from a low conversion rate and difficult separation. In this paper, a three-column process for catalytic distillation applicable in the hydration of cyclohexene to cyclohexanol was established to solve these. Simulation with Aspen Plus shows that the process has good advantages, the conversion of cyclohexene reached 99.3%, and the product purity was ≥99.2%. The stable operation of the distillation system requires a good control scheme. The design of the control scheme is very important. However, at present, the reactive distillation process for cyclohexene hydration is under investigation experimentally and by steady-state simulation. Therefore, three different plant-wide control schemes were established (CS1, CS2, CS3) and the position of temperature sensitive stage was selected by using sensitivity analysis method and singular value decomposition method. The Tyreus-Luyben empirical tuning method was used to tune the controller parameters. Finally, Aspen Dynamics simulation software was used to evaluate the performance of the three control schemes. By introducing ΔF ±20% and x_ENE ±5%, comparison the changes in product purity and yield of the three different control schemes. By comparison, we can see that the control scheme CS3 has the best performance.

关键词: Cyclohexene hydration, Catalytic distillation, Control schemes, Dynamic Simulation