Electro-reduction processes of U3O8 to metallic U bulk in LiCl molten salt

Preparation of U-Nb alloy from oxide precursors by direct oxide electrochemical reduction method

“…The electrochemical reduction pathway of UO 2 in LiCl based melts has been studied extensively using transient electrochemical techniques and by X-ray diffraction technique. 33,38,[41][42][43] Most of the studies have reported direct fourelectron reduction of UO 2 to U metal without any intermediates as observed in this study. Biju Joseph et al recorded a CV of the tip of a UO 2 pellet in LiCl melt at 650 °C and reported three reduction peaks prior to lithium deposition.…”

Electrolytic Reduction of U3O8 and U3O8-MoO3 in CaCl2-NaCl Molten Salt

“…LiCl was that U 3 O 8 was converted into U 4 O 9 and UO 2 , and finally reduced to metallic U. 11 Therefore, we speculated that U 3 O 8 in CaCl 2 -NaCl will not be converted into metallic U in one step, and some intermediate products (e.g. U 4 O 9 and UO 2 ) will also be generated.…”

“…11 Du et al thought that the electrolytic reduction of U 3 O 8 in LiCl at 923 K mainly includes: two compounds of U 4 O 9 (U 4 O 9-y ) and UO 2 were first formed, and was finally UO 2 reduced to metallic U. 11 And it can be observed from Fig. 3 that the potential at which Compared with the cyclic voltammetry in Fig.…”

“…The CV curve with similar phenomena was reported in other studies. 11 Du et al thought that the electrolytic reduction of U 3 O 8 in LiCl at 923 K mainly includes: two compounds of U 4 O 9 (U 4 O 9-y ) and UO 2 were first formed, and was finally UO 2 reduced to metallic U. 11 And it can be observed from Fig.…”

“…2,9 At present, the reprocessing of spent nuclear fuel (SNF) is still one of the great challenges to the nuclear industry. In order to adequately utilize the uranium resource of SNF with increasing burnup and radioactivity, it is suggested to replace hydrometallurgical process with pyroprocessing of SNF in molten salt, 10,11 and the electro-deoxidation method was usually used in the pyroprocessing of the common oxide SNF, such as mixed oxide (MOX) fuels and uranium oxides of light water reactor (LWR). Direct electrochemical reduction of uranium oxides have been studied in forms of UO 2 , [12][13][14][15] U 3 O 8 , 2,11 MOX, 16,17 UO 2 -MoO 3 18 or spent oxide fuels 19 to corresponding metals or alloys in various molten salt such as LiCl, LiCl-Li 2 O, CaCl 2 , CaCl 2 -NaCl and LiCl-KCl-CaCl 2 .…”