Electrochemical Formation of RE-Sn (RE=Dy, Nd) Alloys Using Liquid Sn Electrodes in a Molten LiCl-KCl System

摘要

We proposed new separation and recovery process for Dy metals from Nd magnet scraps using molten salt electrolysis and liquid metals. As the first step, electrochemical formation of RE-Sn (RE=Dy, Nd) alloys were investigated in LiCl-KCl eutectic melts containing DyCl_3(0.50 mol%) or NdCl_3(0.50 mol%). The samples of Nd-Sn alloys were prepared by potentiostatic electrolysis at 0.60, 0.70, 0.80, 1.00 V(vs. Li~+/Li) for 0.50 h using liquid Sn electrodes in LiCl-KCl-NdCl_3(0.50 mol%) melts. The formation of Nd-Sn alloys were confirmed by the XRF analysis of all samples. Moreover, potentiostatic electrolysis were conducted at 0.60 V and 0.70 V for 0.50 h in LiCl-KCl-DyCl_3(0.50 mol%)-NdCl_3(0.50 mol%) melts. The formation of Dy-Nd-Sn alloys were confirmed in the bottom portion of liquid Sn electrodes. The atomic ratios of Nd/Dy in both alloy samples were 3.50.