NaF吸附剂上MoF6的脱附

摘要

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.%为了提高氟化挥发分离工艺中UF6和MoF6的分离效果,研究了MoF6在NaF吸附剂上的脱附行为.通过静态和动态实验考察了温度和载气种类对脱附率的影响.热重分析显示,大部分MoF6在216℃左右脱附,推测其在NaF吸附剂上以MoF6·nNaF配合物的形式存在;还发现在380℃左右出现一个小失重峰,红外漫反射光谱分析证实该失重峰源于Mo配合物的水解.脱附研究表明,在400℃和氟气气氛下,Mo元素能够完全脱附,吸附剂在连续五轮吸附脱附工艺循环后其性能无明显变化.