ARBOK-Dysprosium: Single-Pass Separation of Dysprosium from Dissolved Waste Streams

Heavy rare earths, and dysprosium above all, decide whether a neodymium-iron-boron magnet survives the temperature of an electric-vehicle traction motor. Mining of dysprosium is concentrated in China at over 90%, and separation at about 99%. The separation step, a cascade of hundreds of stages, is the bottleneck on which the concentration rests. This paper describes ARBOK-Dysprosium, a containerised deep-vacuum separation module that treats the whole liquid stream and separates the rare earths into individual oxides (Nd, Pr, Dy, Tb) in a single pass inside the solution, with only final polishing after it. The module is applied not to ore but to three streams in which dysprosium is already dissolved: acid mine drainage, phosphogypsum stack liquor and leachate of end-of-life magnets. We summarise the size of these feedstocks, the product slate (rare-earth oxides, clean water, dry salt fractions) and the economics seen from the side of the waste holder, who stops paying for disposal and starts selling products. The route does not replace mining of the ion-adsorption clays; it removes the dependence on the separation cascade.