Apparatus and method for directly preparing UO2 by molten salt electrolysis of U3O8

The invention provides an apparatus and a method for preparing UO2 through molten salt electrolysis of U3O8. The apparatus comprises an electrolytic tank crucible, chloride molten salt, an inert cathode and an anode device, the inert cathode and the anode device are inserted into the chloride molten salt, and the inert cathode comprises a molybdenum sheet or a tungsten sheet and a corundum sleevewrapping the molybdenum sheet or the tungsten sheet; and the anode device is formed by putting a graphite rod in a quartz glass tube with a closed bottom and with holes formed in the two sides, immersing the small holes in the two sides of the quartz glass tube in the chloride molten salt and sealing the top end of the quartz glass tube. Cl2 generated by electrolysis is applied to dissolution of U3O8 in a chloride molten salt system, so emission of Cl2 can be reduced, and repeated utilization of resources is achieved; and the problem of dissolution of U3O8 in the chloride molten salt can be solved. The process is carr