The electrochemical behavior of Nd(III) and its coreduction with Mg(II) were investigated on a molybdenum electrode at 1023 K in eutectic NaCl-KCl melts. The results indicate that the reduction of NdCl₃ in NaCl-KCl melts is a one-step process with three electrons exchanged, and the reaction is an irreversible diffusion-controlled process at low scan rate with the calculated diffusion coefficient of about 6.8 × 10^-5 cm² s^-1. After MgCl₂ is introduced to the melts, the reduction of Nd(III) takes place at a more positive potential value due to the formation of Mg-Nd intermetallic compounds through electrochemical co-deposition and chemical reduction of Nd(III) ions by preferentially deposited Mg. The solid intermetallic compounds of Mg₃Nd, Mg₂Nd, and MgNd observed in open circuit chronopotentiometry curves are transformed to thermodynamically more stable Mg-rich phases of Mg₁₂Nd and Mg₄₁Nd₅ when potentiostatic electrolysis at -2.10 V. It has been confirmed by X-ray diffraction and SEM-EDS microscopy that the cathodic deposits are composed of Mg, Mg₁₂Nd, Mg₄₁Nd₅, and Nd. The present results confirm that it is an effective method for recycling of neodymium from waste NdFeB magnets by means of electrochemical formation of Mg-Nd alloys from NaCl-KCl-MgCl₂-NdCl₃ melts.

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Electromagnetic fields have been widely applied in the field of materials processing, preparation, and analysis. The effectiveness during such processing is, however, highly dependent on the physics of the applied electromagnetic field as well as the electromagnetic responses from the materials. In order to improve the efficiency of electromagnetic field processing, understanding the fundamentals as well as the engineering of the corresponding electromagnetic effects is crucial. Focusing on metallic materials, this research gives a critical overview and discussion on different electromagnetic effects. Subsequently, the electromagnetic responses in different electromagnetic technologies are further discussed. Specifically, the industrial application potential for inclusion removal from liquid metals is evaluated and the energy coefficient is noticed to be substantially improved by increasing the magnetic flux density.

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As a member of the aluminium composite, GLARE (GLAss fibre/epoxy REinforced aluminium laminates) was used in the upper fuselage of Airbus A380 because of its superior mechanical properties over monolithic aluminium alloys. Thermal processing is a potential method for materials recycling and reuse from GLARE scrap with the aim of environmental protection and economic benefits. Thermal delamination is a crucial pre-treatment step for GLARE recycling. Differential scanning calorimetry (DSC) and Thermogravimetric analysis (TGA) tests have been used to identify the decomposition temperature range of epoxy resins under non-isothermal condition in our previous work [1]. To obtain an appropriate solution for GLARE thermal delamination, the thermal degradation behaviour of epoxy resins in GLARE under isothermal conditions were investigated and isothermal decomposition kinetic models were built up based on DSC and thermogravimetric analysis TGA. The thermal delamination process of GLARE is determined based on thermal analysis results and experimental optimization.@en

Through recycling, reduction and prevention, circulability of metals in the life cycle of electronic products can be significantly improved.@en

In this paper, a detailed study of the electrochemical behavior of zirconium in the molten LiF-KF-ZrF₄ system on an inert molybdenum electrode was carried out at 600 °C. Several electrochemical techniques were employed such as cyclic voltammetry, chronoamperometry and square wave voltammetry. The reduction of zirconium was found to be a multi-step process that at the potentials of 1.15, 1.50 and 1.62 V versus Pt, the corresponding cathodic reactions of Zr⁴⁺/Zr²⁺, Zr²⁺/Zr⁺ and Zr⁺/Zr occurred. The result was further confirmed by the theoretical calculation of the number of transferred electrons according to the cyclic voltammetry and square wave voltammetry analysis. Moreover, based on the cyclic voltammograms, the diffusion coefficient of Zr⁴⁺ ions in the eutectic LiF-KF containing 1 wt% ZrF₄ at 600 °C was estimated to be about 8.31 × 10^-6 cm² s^-1. The present electrochemical study on zirconium in the molten fluoride system will be a theoretical reference for future zirconium electrorefining from Zr alloy or scraps.

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Recovery of valuable metals from electronic waste has been highlighted by the EU directives. The difficulties for recycling are induced by the high complexity of such waste. In this research, copper could be selectively recovered using an ammonia-based process, from industrially processed information and communication technology (ICT) waste with high complexity. A detailed understanding on the role of ammonium salt was focused during both stages of leaching copper into a solution and the subsequent step for copper recovery from the solution. By comparing the reactivity of the leaching solution with different ammonium salts, their physiochemical behaviour as well as the leaching efficiency could be identified. The copper recovery rate could reach 95% with ammonium carbonate as the leaching salt. In the stage of copper recovery from the solution, electrodeposition was introduced without an additional solvent extraction step and the electrochemical behaviour of the solution was figured out. With a careful control of the electrodeposition conditions, the current efficiency could be improved to be 80–90% depending on the ammonia salts and high purity copper (99.9 wt.%). This research provides basis for improving the recyclability and efficiency of copper recovery from such electronic waste and the whole process design for copper recycling.@en

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