Kinetics study and process simulation of reactive distillation for the synthesis of ε-caprolactone

A novel three-stage catalytic reactive distillation (RD) column integrated chemical reaction and distillation process for the continuous synthesis of epsilon-caprolactone (epsilon-CL) was proposed to overcome the disadvantages of previous batch processes. Reaction kinetics according to the two-step indirect oxidation method was studied firstly, which was essential in reactor design and process optimization as well as lacking in the current literature. Kinetics models obtained by data fitting were tested by residual distribution and model statistics. And then, according to the thermodynamic characteristics and reaction kinetics of this process, a steady-state simulation of RD column was carried out with the process simulator Aspen Plus. The influence of operation parameters was investigated on process performance. Under the optimal operating conditions, the conversion of cyclohexanone was 97%, and the mass fraction of epsilon-CL in the bottom products was 62.31%. The simulation showed that RD column worked with excellent results in respect to conversion and product purity because of integrating the processes of chemical reaction and distillation.