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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 NdF3 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 NdF3 in LiF molten salt shows that Nd metal is deposited from the electrolyte on the cathode at the reduction potentials ranging from −1.48 to −1.35 V (vs. W) with the concentration change of NdF3. The final purity of Nd metal deposit is higher than 99.78 %.

In this paper, we describe an attractive and rapid process for preparing zirconium metal (sponge and powder) by reacting zirconium tetrachloride with magnesium powder. The process was carried out in the combustion synthesis (shortly CS) mode using a ZrCl4–2Mg exothermic mixture, which provided a temperature of 1000–1100 °C and a final product consisting of MgCl2 and Zr sponge. The separation of Zr sponge from the reaction product was accomplished by dissolving MgCl2 into warm acidified water. The average size of the Zr sponge particles ranged from about 1 mm to about 10 mm. Micrometer-sized (from 10 to 300 μm) Zr powders were also obtained after mechanical processing of sponge. The characteristics of the Zr metal were established by X-ray diffraction, scanning electron microscopy, and inductively coupled plasma spectroscopy techniques.

Cu-Ag powder having Core-Shell structure was prepared from by electroless plating method using agents such as , , Hydroquinone. Ag coated copper powders were analyzed using scanning electron microscopy(SEM) and energy dispersive X-ray spectrometer(EDX). The silver coating layer of copper powder was affected from various reaction conditions such as molar ratio of , , and pulp density. Free silver was generated below 0.1M or 0.3M and above of mole ratio. Silver coating layer thickened as addition of . When the pulp density reached 12% with 0.2M , and 0.15M at , silver was homogeneously distributed around the copper particles and free silver particles were not generated.