The potential/pO2− diagrams of uranium and the feasibility of a pyrochemical head-end treatment of nuclear fuels in molten chlorides

Electrochemistry of rare earth oxy ions REO+ (RE=Ce, La, Nd) in molten MgCl2–NaCl–KCl eutectic

“…2 and 3, respectively. The cyclic voltammograms of the rare earth oxides suggests the presence of REO + ions in the melt since the stabilities and hence the formation of oxychlorides are dependent on the oxoacidity properties of melts, as has been observed in the recent studies on rare earth-oxygen systems [17][18][19][20][21][22][23]. Our results showing the presence of rare earth oxychlorides in MgCl 2 -NaCl-KCl eutectic are also substantiated by the XPS of cerium oxychloride [10] [19,20].…”

Uranium (III) precipitation in molten chloride by wet argon sparging

“…The chemistry of uranium in molten chloride is well described by Martinot et al [5] through the Pourbaix diagram in eutectic LiCl-KCl at 450 C. This diagram presents the stability of soluble and insoluble uranium species as a function of the potential and the O 2À concentration in the salt. It highlights the rich diversity of stable oxidation states of uranium in these medias with, for low O 2À concentration the presence of many soluble species U 3þ , U 4þ , UO [5,10]. These compounds emphasize the importance of a moderate oxidative way of precipitation to avoid an oxidation over the oxidation state (IV) and a pollution of the final powder with alkaline or alkaline hearth metal.…”

First-Principles Molecular Dynamics Simulations of UCln–NaCl (n = 3, 4) Molten Salts

“…In this process, the LiCl–KCl eutectic was used as the electrolyte to transport actinide ions from the anode to the cathode. Absent of O 2– ions in the melt, U exists mainly as U­(III) or U­(IV), depending on the electrode potential . The structures of pure UCl 3 molten salt and its mixture with LiCl–KCl eutectic were examined by Okamoto et al with high temperature X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS). − They further used classical molecular dynamics (CMD) simulations with the polarizable ion model (PIM) to interpret the X-ray data.…”