High-purity Nd metal was recovered from waste Nd–Fe–B magnet by the molten salt electrowinning process with chemical pretreatment. X-ray diffraction（XRD）, scanning electron microscopy（SEM）, energy dispersive spe...High-purity Nd metal was recovered from waste Nd–Fe–B magnet by the molten salt electrowinning process with chemical pretreatment. X-ray diffraction（XRD）, scanning electron microscopy（SEM）, energy dispersive spectroscopy（EDS）, cyclic voltammetry（CV）,chronopotentiometry（CP）, and inductively coupled plasma-atomic emission spectrometer（ICP/AES） were used to characterize the deposit and electrochemical behaviors. The results show that NdF_3 is effectively synthesized from the Nd–Fe–B magnet using HCl solution and NH4F. During the chemical treatment of the waste magnet,iron impurity is eliminated as a soluble [NH4]3[FeF6]complex. Electrowinning using NdF_3 in LiF molten salt shows that Nd metal is deposited from the electrolyte onthe cathode at the reduction potentials ranging from-1.48to-1.35 V（vs. W） with the concentration change of NdF_3.The final purity of Nd metal deposit is higher than99.78 %.展开更多
基金financially supported by the Korea Institute of Energy Technology Evaluation and Planning(KETEP) of the Korea Government Ministry of Knowledge Economy (No. 20122010300041)the National Research Foundation of Korea (No. 2011-0091839)
文摘High-purity Nd metal was recovered from waste Nd–Fe–B magnet by the molten salt electrowinning process with chemical pretreatment. X-ray diffraction（XRD）, scanning electron microscopy（SEM）, energy dispersive spectroscopy（EDS）, cyclic voltammetry（CV）,chronopotentiometry（CP）, and inductively coupled plasma-atomic emission spectrometer（ICP/AES） were used to characterize the deposit and electrochemical behaviors. The results show that NdF_3 is effectively synthesized from the Nd–Fe–B magnet using HCl solution and NH4F. During the chemical treatment of the waste magnet,iron impurity is eliminated as a soluble [NH4]3[FeF6]complex. Electrowinning using NdF_3 in LiF molten salt shows that Nd metal is deposited from the electrolyte onthe cathode at the reduction potentials ranging from-1.48to-1.35 V（vs. W） with the concentration change of NdF_3.The final purity of Nd metal deposit is higher than99.78 %.
