Abstract: Reaction process for the preparation of phosphorus pentafluoride with phosphorus pentachloride and lithium fluoride was studied at 150~195 ℃.Shrinking core model was used to simulate the data and the kinetic model of the reaction was obtained:the earlier period from start to 0.5 h was controlled by chemical reaction,the kinetic equation was:k_s=22.2exp[-34 490/(R_gT)];the later period from 1 h to 3 h is controlled by diffusion control,the dynamic equation was：D_e=4.357×10^-7exp[-29 980/(R_gT)].This study aims to reveal the related laws of the reaction between phosphorus pentachloride and lithium fluoride to prepare phosphorus pentafluoride and provides necessary data for the industrial production of phosphorus pentafluoride.

Key words: phosphorus pentafluoride, shrinking core model, kinetics