Solid oxide membrane-assisted electrolytic reduction of Cr2O3 in molten CaCl2

Bo Wang; Chao-yi Chen; Jun-qi Li; Lin-zhu Wang; Yuan-pei Lan; Shi-yu Wang

doi:10.1007/s12613-020-2141-x

Volume 27 Issue 12

Dec. 2020

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2020 > 27(12): 1626-1634

Bo Wang, Chao-yi Chen, Jun-qi Li, Lin-zhu Wang, Yuan-pei Lan, and Shi-yu Wang, Solid oxide membrane-assisted electrolytic reduction of Cr₂O₃ in molten CaCl₂, Int. J. Miner. Metall. Mater., 27(2020), No. 12, pp. 1626-1634. https://doi.org/10.1007/s12613-020-2141-x

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Bo Wang, Chao-yi Chen, Jun-qi Li, Lin-zhu Wang, Yuan-pei Lan, and Shi-yu Wang, Solid oxide membrane-assisted electrolytic reduction of Cr2O3 in molten CaCl2, Int. J. Miner. Metall. Mater., 27(2020), No. 12, pp. 1626-1634. https://doi.org/10.1007/s12613-020-2141-x

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Research Article

Solid oxide membrane-assisted electrolytic reduction of Cr₂O₃ in molten CaCl₂

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Corresponding author:
Chao-yi Chen E-mail: ccy197715@126.com
Received: 20 May 2020; Revised: 5 July 2020; Accepted: 9 July 2020; Available online: 12 July 2020

Abstract

Abstract

Solid oxide membrane-assisted electrolytic reduction of solid Cr₂O₃ to Cr in molten CaCl₂ was performed using a sintered porous Cr₂O₃ cathode paired with an yttria-stabilized zirconia (YSZ) tube anode containing carbon-saturated liquid copper alloy. Analyses of the reduction mechanism, ion migration behavior, and effects of cathode pellet porosity and particle size on the electrolysis products and reduction rate revealed that the cathode microstructure and electrolytic conditions were key factors influencing the electrolysis process. Optimal results were obtained when the cathode was characterized by high porosity and a small particle size because this combination of features contributed to ion migration. Good electrochemical activation was observed when cathode pellets prepared by 4 MPa molding followed by 2 h of sintering at 1150°C were applied. The electrode reduction process (Cr³⁺ → Cr²⁺ → Cr) was promoted by high electrode voltages, and Cr metal was efficiently formed. The proposed method appears to be well suited for electrolytic Cr production because it does not require expensive pre-electrolysis techniques or generate harmful by-products.
- solid oxide membrane;
- yttria-stabilized zirconia;
- electrometallurgy;
- chromium;
- molten salt

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