, Volume 69, Issue 10, pp 1987–1991 | Cite as

Thermodynamic Investigation of the Reduction-Distillation Process for Rare Earth Metals Production

  • W. D. Judge
  • G. AzimiEmail author


Owing to their high vapor pressure, the four rare earth metals samarium, europium, thulium, and ytterbium are produced by reduction-distillation whereby their oxides are reduced with metallic lanthanum in vacuo, and the produced metal is subsequently vaporized off. Here, we performed a thorough thermodynamic investigation to establish a fundamental understanding of the reduction-distillation process. Thermodynamic functions including vapor pressures, Gibbs free energies, and enthalpies of reaction were calculated and compared with available experimental data. Furthermore, the kinetics of the process was explored and theoretical evaporation rates were calculated from thermodynamic data. The thermodynamic model developed in this work can help optimize processing conditions to maximize the yield and improve the overall process.



The authors gratefully acknowledge the financial support of the Natural Sciences and Engineering Research Council (NSERC) of Canada (Grant Number 498382) and thank Cheen Aik Ang for providing thoughtful comments and suggestions in preparing this manuscript.

Supplementary material

11837_2017_2473_MOESM1_ESM.docx (306 kb)
Supplementary material 1 (DOCX 306 kb)


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Copyright information

© The Minerals, Metals & Materials Society 2017

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringUniversity of TorontoTorontoCanada
  2. 2.Department of Chemical Engineering and Applied ChemistryUniversity of TorontoTorontoCanada

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