Extraction of neodymium by direct reduction of NdOCl in molten calcium chloride

The direct electrochemical extraction of neodymium using a modified (Fray-Farthing-Chen) FFC process is proposed in this article. In this modified FFC process, NdOCl, prepared from the reaction of Nd₂O₃ and CaCl₂ was used as the cathode and an yttria stabilized zirconia (YSZ) tube loaded with tin was used to separate the anode from the molten electrolyte. NdOCl reduction occurs in two steps: NdOCl to NdO and NdO to Nd, as determined by cyclic voltammetry. The diffusion coefficients of NdO⁺ and oxygen ions were also calculated for each step. A cell voltage of 3.6 V was found to be sufficient to have a reduction of NdOCl to Nd metal.