微波耦合结构化催化剂协同强化气固相催化反应机理

结构化催化剂可以实现催化剂设计与反应器设计结合，在气固相催化氧化反应中表现出高催化活性组分利用率、强化传质/传热的显著优势。微波加热可以选择性加热具有吸波性能的结构化催化剂，将其与结构化催化剂耦合，可进一步提高催化过程能量利用率，促进传质与传热同向进行，提高催化剂抗积碳能力。其中，提高催化剂对特定频段微波的吸收性能是影响微波加热耦合结构化催化剂的关键。本课题从微波吸收催化剂设计、制备和微波协同作用机制三个关键科学问题出发，建立“电-磁-热”多场耦合催化剂模型，确定微波吸收催化剂设计总体原则；通过3D打印结合应烧结及表面修饰调控载体吸波性能；通过活性组分组成和形貌来调控其微波吸收性能；以甲苯催化氧化为模型反应，对比研究微波和常规加热条件下催化剂演变规律和反应动力学，结合电磁学仿真澄清微波耦合结构化催化剂协同强化气固相催化反应机理，为化工过程强化技术在气固相反应中的应用提供理论支撑。

The structured catalyst can realize the combination of the catalyst design and the reactor design, and shows the significant advantages of improving the utilization of the active component and enhancing the mass and heat transfer in the gas-solid phase catalytic oxidation reaction. Microwave can selectively heat the structured catalyst with microwave absorption properties. If the two are coupled, the energy utilization rate of the catalytic process will be further improved, the mass transfer and the heat transfer will be promoted in the same direction, and the ability of the catalyst to resist carbon deposition will be improved. Among them, how to improve the absorption performance of the catalyst for microwaves in a specific frequency band is the key to affecting the selective heating of the catalyst by microwaves. Starting from the three key scientific issues of microwave absorption catalyst design, preparation and microwave synergy mechanism, this work uses finite element electromagnetic simulation to establish an "electro-magnetic-thermal" multi-field coupling catalyst model to determine the overall principles of microwave absorption catalyst design; through 3D printing technology combines the active liquid phase reaction sintering process and the surface silicon carbide whisker modification to adjust the microwave absorption performance of the catalyst support; the microwave absorption performance of the active component is adjusted by controlling the active component composition and morphology; the toluene catalytic oxidation is used as the model reaction. A comparative study of the catalyst evolution and reaction kinetics under microwave heating and conventional heating conditions, combined with electromagnetic simulation to clarify the mechanism of the microwave-coupled structured catalyst synergistically strengthening the gas-solid catalytic reaction. And it provides theoretical support for the application of chemical process intensification technology in gas-solid reaction.