Semi-continuous calciothermal reduction and production of rare earth elements

image of Mg-Nd ingot produced by calciothermic reduction of the chloride to produce >50-lb batches.

 

Top: Mg-Nd ingot produced by calciothermic reduction of the chloride to produce >50-lb batches. After reduction, samples are refined by distillation and arc melting to produce neodymium metal with low oxygen content for use in magnet production. Vacuum arc melted sample, bottom, demonstrated <1500 ppm oxygen.
Top: Mg-Nd ingot produced by calciothermic reduction of the chloride to produce >50-lb batches. After reduction, samples are refined by distillation and arc melting to produce neodymium metal with low oxygen content for use in magnet production. Vacuum arc melted sample, bottom, demonstrated <1500 ppm oxygen.

CMI researchers at Terves conducted the research for this highlight

Innovation 
Pilot-scale demonstration of rare earth alloy production from oxide and feasibility demonstration of refined Nd metal.

Achievement

  • Anhydrous neodymium chloride was reduced at pilot scale.
  • Distillation demonstrated removal of major alloying elements with <1000 ppm oxygen.
  • Vacuum arc melting demonstrated a >96% pure Nd metal with <1100 ppm oxygen and low levels of carbon, nitrogen and sulfur.

Significance and Impact
Terves has demonstrated feasibility of domestic rare earth alloy production using existing magnesium casting infrastructure.

Hub Target Addressed
Demonstrate feasibility of a domestic rare earth metal processing facility.