Investigation on Chlorination of Uranium Oxides With CCl4 and HCl Gas

Abstract

In this study, the chlorination mechanism and influencing factors of uranium oxides(mainly U3O8) were studied by using CCl4 and HCl gas as chlorination reagents respectively. The chlorination of U3O8 powder was studied with CCl4 as chlorination reagent. The mechanism and kinetic behavior of the chlorination reaction were studied by thermogravimetric analysis. The main chlorination product is UCl4. The chlorination of different types and morphologies of uranium oxide by CCl4 was also studied. The UO2 pellets are difficult to chlorinate due to their very dense structure. UO2 powder and UO3 powder are easily chlorinated by CCl4, and the chlorination products are UCl4 and UCl6 respectively. The chlorination of U3O8 powders in LiCl-KCl molten salt system was carried out using HCl gas as the chlorination reagent. The effects of reaction temperature, chlorination time, HCl gas flow rate, feeding amount of U3O8 powder, and uranium oxide types and morphologies were studied. The results show that increasing the reaction temperature, prolonging the reaction time, and increasing the HCl gas flow rate are beneficial to the improvement of the chlorination rate. The process parameters of HCl gas chlorinated U3O8 powder are recommended as follows: the chlorination reaction temperature is 500 ℃, and the flow rate of HCl gas is 0.6 L/min.

Keywords

• uranium oxides
• chlorination reagent
• ccl4
• hcl gas