Abstract: In order to improve the decontamination efficiency of MoF₆ in the uranium separation process via. volatile fluoride, the desorption of MoF₆ from the NaF adsorbent was studied in this paper. Effects of the temperature and the species of carrier gas on desorption ratios were examined by variety of static and dynamic tests. Thermogravimetric analysis show that most of MoF₆ is able to be desorbed at around 216 ℃, thus it is speculated that they exist originally in the form of MoF₆•nNaF complexes. Importantly, a small weightlessness peak of Mo appeared at 380 ℃ is found, and the weightlessness peak will be originated from Mo hydrolysis complexes. The infrared diffuse reflection spectroscopy further confirms all the results mentioned above. Simulation test shows that Mo could be desorbed completely at 400 ℃ in the atmosphere of F₂, and the performance of the adsorbent has no obvious changes after five adsorption-desorption cycle experiments.