Neodymium is classified as a critical raw material of the European Union owing to its key role in Nd$_2$Fe$_{14}$B permanent magnets. Its supply depends heavily on imports from China, while the share recovered from end-of-life products remains negligible, which – combined with growing demand in electromobility, wind power and robotics – poses a supply risk for European industry. Based on a review of the available literature, this thesis addresses the recovery of neodymium from end-of-life NdFeB magnets by molten salt electrolysis. The composition, physical and magnetic properties, protective coatings and fields of application of NdFeB magnets are presented first, together with the types of waste in which they occur. The established groups of recycling methods are then compared: direct reuse, hydrogen decrepitation, hydrometallurgy, pyrometallurgy and electrometallurgy. The central part is devoted to molten salt electrolysis, namely its operating principle, the selection of electrolytes and electrodes, and the process and design variables that govern selectivity, yield and product purity. Six laboratory implementations of the process are presented, differing in the way neodymium is converted into a soluble compound, in electrolyte composition and in cathode type, together with the NdCycle2 pilot project carried out within EIT RawMaterials. On this basis, a CAD model of a laboratory reactor for electrolysis in a eutectic LiF–CaF$_2$ melt at 950 °C under a purified argon atmosphere was developed in Creo. The model comprises a body and lid made of a high-temperature alloy, chemical protection of alumina and quartz, a graphite crucible and both electrodes, and provides a starting point for subsequent thermal simulations and the construction of a prototype.
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