Kinetics and catalytic distillation simulation for the heterogeneously catalytic synthesis of imine

(2-methyl-6-ethylphenyl)-1-methoxypropyl-2-imine (MEMI) is an important intermediate for the synthesis of commercial pesticide S-metolachlor. However, the research on heterogeneously catalytic kinetics of MEMI, and further the catalytic distillation simulation aiming at continuous operation, have never been reported. Herein, the catalytic kinetics for the synthesis of MEMI by HPW/Al-MCM-41 have been systematically investigated, and further fitted by using a pseudo-homogeneous kinetic model, based on which, the reaction equilibrium constant, activation energy, and rate constant are obtained. Furthermore, simulation of the continuous process of MEMI synthesis was carried out using the software Aspen Plus V10. Sensitivity analysis of operating parameters such as feed stage, distillation rate, number of reactive theoretical stages, and the best operating conditions were also obtained. An excellent product purity (>98.9%) of MEMI could be achieved when operated at the optimum conditions. Compared with the batch method, catalytic distillation provided continuous synthesis of MEMI, and the reaction was more thorough, achieving process integration and optimization. Our results provide substantial theoretical and empirical supports for the industrial synthesis of MEMI.