Gha-Young Kim

Reusability Test for Ceramic Crucibles as Liquid Cadmium Cathode Containers inPyroprocessing

The compatibility of various ceramic crucibles (AlN, BeO, and SiC) for repeated use in pyroprocessing was investigated. Each ceramic crucible loaded with liquid cadmium was immersed in molten chloride salt containing uranium and rare earth elements (Nd, Ce, and La) at 500 °C to perform an electrodeposition, followed by heating to 920°C to separate the metal deposits from Cd during distillation. Repeated process runs showed that the ceramic crucibles could be recycled and reused, more specifically, 7 times for AlN, >13 times for BeO, and 4 times for the SiC crucible. Considering the reactivity of ceramic materials with metal deposits as well as their durability at high temperature, the crucible composed of BeO was concluded to be suitable for use in electrorefining and distillation.

Electrochemical Behavior of Li-B Alloy Anode - Liquid Cadmium Cathode (LCC) System for Electrodeposition of Nd in LiCl-KCl

The performance of Li-B alloy as anode for molten salt electrolysis was firstly investigated. The crystalline phase of the prepared Li-B alloy was identified as Li7B6. The potential profile of Li-B alloy anode was monitored during the electrodeposition of Nd 3+ onto an LCC (liquid cadmium cathode) in molten LiCl-KCl salt at 500 o C. The potential of Li-B alloy was increased from -2.0 V to -1.4 V vs. Ag/AgCl by increasing the applied current from 10 to 50 mA·cm -2 . It was found that not only the anodic dissolution of Li to Li + but also the dissolution of the atomic lithium (Li 0 ) into the LiCl-KCl eutectic salt was observed, fol- lowing the concomitant reduction of Nd 3+ by the Li 0 in Li-B alloy. It was expected that the direct reduction could be restrained by maintaining the anode potential higher that the depo- sition potential of neodymium.