Study On Catalytic Reactive Distillation Process Intensified By Microwave Irradiation

Many processes of reactive distillation have been developed and applied to industrial production in the last several decades. However, due to the limitations of reactive distillation technology, such as the slow reaction rate or reaction conditions and distillation conditions are not matching, the reactive distillation technology does not apply to all of the reaction system. In this paper, microwave irradiation is used in reactive distillation for ravelling out the limitations of the reactive distillation, resulting the conditions of reaction and distillation is matching. A new process coupling intensification technology - microwave reactive distillation technology is developed. DOP esterification reaction system is used as the research object, the process of microwave reactive distillation esterification and its contents were studied systematically.In this paper, the basic research of microwave reactive distillation process is divided to two aspects: (1) The reaction kinetics of the microwave field. The reactive kinetics of DOP esterification is determined in the self-made microwave reactor, and compared with the reaction rate under conventional heating. To understanding the special effect of DOP esterification reaction under microwave field, and reaction kinetics equation of DOP esterification has been determined in the microwave field catalyzed by tetrabutyl titanate; (2) Vapor-liquid equilibrium under the microwave field. Vapor-liquid phase equilibrium data of Ethanol-Benzene and Isooctanol-DOP two binary systems are measured at different microwave power using self-made vapor-liquid equilibrium apparatus. The expermental data are compared with the conventional vapor-liquid equilibrium data, the effects of the microwave field on the vapor-liquid equilibrium are achieved. The two groups experimentals data are correlated with the UNIQUAC model.For the experimental part of microwave reactive distillation process, the packing specially used in microwave field packing——MRDPAK packing is developed. Hydrodynamics and mass transfer properties of MRDPAK packing are determined. Microwave reaction distillation column packing MRDPAK is established, and experimental is carried out by isooctanol stripping esterification microwave reactive distillation process technology developted by this paper. Compared with conventional reactive distillation and ordinary microwave reactive distillation, the results show that the process technology of isooctanol stripping microwave reactive distillation is better than other process technologys.The steady-state equilibrium stage model of DOP esterification microwave reactive distillation process is developed, and the simulation and analysis of DOP esterification microwave reactive distillation process using this model are carried out. The results of simulation agree well with experimental results of this paper shows that the model is enough to describing the process. The optimized operation conditions, such as feed location, reflux ratio, feed molar ratio of monoester, the height of the rectifying section and reaction, microwave power, reaction Packing liquid holdup, and other factors, are achieved depending on systematic simulation. The relevant results provide the guidance and reference for design and industrialization of DOP esterification microwave reactive distillation process.