Neodymium Distribution between Cu-rich and Fe-rich Phases in Two Immiscible Liquids in Fe–Cu–C System

Abstract

Recovery of Nd from used products is a crucial problem to be solved for a stable supply of Nd resource. In the present work, the use of two immiscible liquids, i.e. a Cu-rich phase and an Fe-rich phase, in an Fe-Cu-C system was regarded as one of the solutions for this purpose and the distributions of Nd between two immiscible liquids in an Fe-Cu-C system were measured. We found Nd is distributed in the Cu-rich phase more than in the Fe-rich phase in an Fe-Cu-C system and Nd is more concentrated at low temperatures than at high temperatures. In addition, the thermodynamic parameters for Nd were obtained based on the experimental results.

Molten Oxide Electrolysis Using Copper-Containing Carbon-Saturated Molten Iron Anode

“…8, the change in the contact morphology of the metal and slag caused by the anodic polarization of the Cucontaining carbon-saturated molten iron is thought to be caused by the mechanism by which Cu is concentrated at the interface. Due to the difference in the specific gravity of Fe and Cu 47,48 the Cu-rich phase precipitates in the lower part of the molten Fe-Cu-C metal phase. When the metal-slag interface is nobly polarized, the interfacial energy between the metal and slag is reduced as a result of the electric capillary effect.…”

“…Two-liquid phase separation is known to occur in carbon-saturated Fe-Cu-C alloys. 35 The morphology of the interface between liquid Fe-Cu-C alloy and molten slag during an electrochemical reaction has not been fully clarified, and it is necessary to elucidate the behavior of the interface as a multiphase flow. The interfacial behavior of Cu-containing carbon-saturated molten Fe is investigated in this study when it is anodically polarized in molten slag.…”

Effect of Electromagnetic Forces on Separation of Two Immiscible Liquids in the Fe–Cu–C System

“…1) The use of two immiscible liquids in the Fe-Cu-C system is proposed for recycling motors that use Nd magnets. 2) When C is added to molten Fe-Cu, the molten metal separates into two immiscible liquids, one of which is a Fe-C-rich liquid and the other a Cu-rich liquid.…”