The reduction path of the U3O8 powder vol-oxidized at 1200 degrees C has been determined by a series of electrochemical experiments in a 1 wt.% Li2O/LiCl molten salt. Various reaction intermediates are observed by during electrolysis of U3O8. The formation of the metallic uranium is caused from two different reduction paths, a direct reduction of uranium oxide and an electro-lithiothermic reduction. As the uranium oxide is converted to the metallic uranium, the lithium metal is more actively formed in the cathode basket. The reducibility of the rare earth oxides with the U3O8 powder has been tested by constant voltage electrolysis. The results suggest the advanced vol-oxidation could lead to the enhancement in the reducibility of the rare earth fission products. (C) 2009 Elsevier Ltd. All rights reserved.