Microwave-Assisted Direct Fluorination of Polymers in Vibro-Fluidized Beds: From Reaction Kinetics to Reactor Design

Direct fluorination of polymers is a key surface modification technology for producing high-performance fluorinated materials, but conventional batch and screw reactors face long-standing problems such as low heat transfer efficiency, severe particle attrition, and inconsistent product quality in industrial production. This paper reviews the process intensification strategy of polymer direct fluorination based on the combination of vibro-fluidized bed technology and microwave-assisted heating from the perspective of reaction engineering. The radical chain mechanism and kinetic characteristics of direct fluorination are briefly introduced, and the hydrodynamic advantages of vibro-fluidized beds in improving gas-solid contact uniformity and reducing particle attrition are analyzed. The enhancement mechanism of microwave volumetric heating on reaction kinetics and the self-regulating heating effect caused by the evolution of polymer dielectric properties are discussed. On this basis, a conceptual design of a continuous circulating vibro-fluidized bed microwave fluorination reactor with closed-loop gas purification and recycling is proposed, and its process flow, key structural modules and main operating parameters are systematically described. Finally, the main technical challenges in pilot-scale application, including particle attrition control, process safety and scale-up methods, are summarized, and corresponding future research directions are pointed out. The review can provide a reference for the upgrading and optimization of industrial polymer fluorination processes.