Neodymium is classified as a critical raw material of the European Union owing to its
key role in Nd2Fe14B 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–CaF2 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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