Study on the Electrodeoxidation of Solid Dy₂O₃ in Molten CaCl₂

Abstract:

The electrodeoxidation of Dy₂O₃ for preparing metal Dy in CaCl₂ melt was studied by cyclic voltammetry, constant potential electrolysis techniques and thermodynamics analysis. Two electrodes system was employed during measuring cyclic voltammetry. Only one cathodic current peak(at about -1.75V ) was discovered before the decomposition of CaCl₂ which corresponded to the electrodeoxidation of Dy₂O₃ in the cyclic voltammograms in molten CaCl₂ at 850°C. The validity of the cyclic voltammograms was further confirmed by thermodynamics analysis and the CO₂、CO anodic gas detected. In constant potential electrolysis products there were no other intermediates except Dy₂O₃ and Dy observed by XRD. And the results confirmed the following electrodeoxidation sequence: Dy₂O₃→Dy.

• Periodical: Advanced Materials Research (Volumes 391-392)
• Pages: 955-959
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.391-392.955
• Online since: December 2011
• Authors: Hong Wei Xie, Pyong Hun Kim, Jin Xia Wang, Yu Chun Zhai, Xiang Yu Zou, Xiao Chuan Lang
• Keywords: Dy, Dy₂O₃, Electrodeoxidation, Molten CaCl₂

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