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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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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.
| [1] |
A.W. Espelund, Aluminothermic reduction. An illustrative experiment, J. Chem. Educ., 52(1975), No. 6, p. 400. doi: 10.1021/ed052p400
|
| [2] |
Y.L. Bai, H.B. Xu, Y. Zhang, and Z.H. Li, Synthesis and characterization of ultra-fine Cr2O3 from hydrogen reduction of K2CrO4, J. Wuhan Univ. Technol. Sci. Ed., 23(2008), No. 2, p. 181. doi: 10.1007/s11595-006-2181-8
|
| [3] |
X. Wei and D.H. Wang, Rare metals preparation by electro-reduction of solid compounds in high-temperature molten salts, Rare Met., 35(2016), No. 8, p. 581. doi: 10.1007/s12598-016-0778-4
|
| [4] |
D.J. Fray, Emerging molten salt technologies for metals production, JOM, 53(2001), No. 10, p. 27.
|
| [5] |
K. Zhao, Y.W. Wang, and F. Gao, Electrochemical extraction of titanium from carbon-doped titanium dioxide precursors by electrolysis in chloride molten salt, Ionics, 25(2019), No. 12, p. 6107. doi: 10.1007/s11581-019-03149-4
|
| [6] |
S.L. Wang, S.C. Li, L.F. Wan, and C.H. Wang, Electro-deoxidation of V2O3 in molten CaCl2−NaCl−CaO, Int. J. Miner. Metall. Mater., 19(2012), No. 3, p. 212. doi: 10.1007/s12613-012-0540-3
|
| [7] |
Y.K. Wu, Z.G. Xu, S. Chen, L.J. Wang, and G.X. Li, Electrochemical behavior of zirconium in molten NaCl−KCl−K2ZrF6 system, Rare Met., 30(2011), No. 1, p. 8. doi: 10.1007/s12598-011-0187-7
|
| [8] |
Z.F. Cai, Z.M. Zhang, Z.C. Guo, and H.Q. Tang, Direct electrochemical reduction of solid vanadium oxide to metal vanadium at low temperature in molten CaCl2-NaCl, Int. J. Miner. Metall. Mater., 19(2012), No. 6, p. 499. doi: 10.1007/s12613-012-0586-2
|
| [9] |
W. Han, M. Li, M.L. Zhang, and Y.D. Yan, Progress in preparation of rare earth metals and alloys by electrodeposition in molten salts, Rare Met., 35(2016), No. 11, p. 811. doi: 10.1007/s12598-016-0798-0
|
| [10] |
C.Y. Chen, X.G. Lu, C.H. Li, and Q.D. Zhong, Application of three-phase interline reaction mechanism on preparation of Ta metal using SOM process, Chin. J. Nonferrous Met., 19(2009), No. 3, p. 583.
|
| [11] |
G.H. Qiu, D.H. Wang, X.B. Jin, X.H. Hu, and Z. Chen, Investigation of the direct electrochemical reduction of Cr2O3 powder in molten CaCl2 by a metallic cavity electrode, Electrochemistry, 12(2006), No. 3, p. 304.
|
| [12] |
Z.W. Liu, H.L. Zhang, L.L. Pei, Y.L. Shi, Z.H. Cai, H.B. Xu, and Y. Zhang, Direct electrolytic preparation of chromium metal in CaCl2–NaCl eutectic salt, Trans. Nonferrous Met. Soc. China, 28(2018), No. 2, p. 376. doi: 10.1016/S1003-6326(18)64671-0
|
| [13] |
X.F. Guan, U.B. Pal, and A.C. Powell, An environmentally friendly process involving refining and membrane-based electrolysis for magnesium recovery from partially oxidized scrap alloy, JOM, 65(2013), No. 10, p. 1285. doi: 10.1007/s11837-013-0659-3
|
| [14] |
C.Y. Chen, Y.L. Lv, and Z.H. Mao, Comparison of SOM and FFC processes for preparation of sponge titanium, Guangzhou Chem. Ind., 41(2013), No. 10, p. 60.
|
| [15] |
C.Y. Chen, Y.L. Lv, and J.Q. Li, Reaction mechanism on preparation of Ta with SOM process, Adv. Mater. Res., 690-693(2013), p. 30. doi: 10.4028/www.scientific.net/AMR.690-693.30
|
| [16] |
C.Y. Chen, X.Q. Yang, J.Q. Li, X.G. Lu, and S.F. Yang, Direct electrolytic reduction of solid Ta2O5 to Ta with SOM process, Metall. Mater. Trans. B, 47(2016), No. 3, p. 1727. doi: 10.1007/s11663-016-0633-x
|
| [17] |
Y.Y. Shen, C.Y. Chen, J.Q. Li, and Y.P. Lan, Preparation of titanium by SOM electrolytic process from ultrafine high titanium slag, Rare Met. Mater. Eng., 48(2019), No. 5, p. 1671.
|
| [18] |
A. Krishnan, U.B. Pal, and X.G. Lu, Solid oxide membrane process for magnesium production directly from magnesium oxide, Metall. Mater. Trans. B, 36(2005), No. 4, p. 463. doi: 10.1007/s11663-005-0037-9
|
| [19] |
S.L. Wang and Y.J. Li, Reaction mechanism of direct electro-reduction of titanium dioxide in molten calcium chloride, J. Electroanal. Chem., 571(2004), No. 1, p. 37. doi: 10.1016/j.jelechem.2004.04.010
|
| [20] |
Z.Q. Li, L.Y. Ru, C.G. Bai, N. Zhang, and H.H. Wang, Effect of sintering temperature on the electrolysis of TiO2, Int. J. Miner. Metall. Mater., 19(2012), No. 7, p. 636. doi: 10.1007/s12613-012-0606-2
|
| [21] |
X.Y. Liu, M.L. Hu, C.G. Bai, and X.W. Lv, Effect of electrical conductivity and porosity of cathode on electro-deoxidation process of ilmenite concentrate, Rare Met. Mater. Eng., 46(2017), No. 5, p. 1176. doi: 10.1016/S1875-5372(17)30132-7
|
| [22] |
G.Z. Chen, E. Gordo, and D.J. Fray, Direct electrolytic preparation of chromium powder, Metall. Mater. Trans. B, 35(2004), No. 2, p. 223. doi: 10.1007/s11663-004-0024-6
|
| [23] |
Y.S. Wei, S.H. Yan, L. Zhou, D.H. Chen, R.Y. Miao, and Z.Q. Wang, Formation mechanism and preparation of YAl2 intermetallics by electro-deoxidation with different sintering conditions, Rare Met.(2017). DOI: 10.1007/s12598-016-0845-x
|
| [24] |
G. Xie, Theory and Application of Molten Salt, Metallurgical Industry Press, Beijing, 1998.
|
| [25] |
J.X. Song, Q.Y. Wang, G.J. Hu, X.B. Zhu, S.Q. Jiao, and H.M. Zhu, Equilibrium between titanium ions and high-purity titanium electrorefining in a NaCl−KCl melt, Int. J. Miner. Metall. Mater., 21(2014), No. 7, p. 660. doi: 10.1007/s12613-014-0955-0
|
| [26] |
K.S. Mohandas and D.J. Fray, FFC Cambridge process and removal of oxygen from metal-oxygen systems by molten salt electrolysis: An overview, Trans. Indian. Inst. Met, 57(2004), No. 6, p. 579.
|
| [27] |
E. Gordo, G.Z. Chen, and D.J. Fray, Toward optimisation of electrolytic reduction of solid chromium oxide to chromium powder in molten chloride salts, Electrochim. Acta, 49(2004), No. 13, p. 2195. doi: 10.1016/j.electacta.2003.12.045
|
| [28] |
Z.W. Liu, H.L. Zhang, L.L. Pei, G.J. Zhu, H.B. Xu, and Y. Zhang, Investigations on reaction pathway and microstructure transformations during electrochemical reduction of Cr2O3 in molten CaCl2, J. Electrochem. Soc., 163(2016), No. 9, p. H781. doi: 10.1149/2.0621609jes
|
| [29] |
X.Y. Liu, M.L. Hu, C.G. Bai, and X.W. Lv, Formation behavior of CaTiO3 during electrochemical deoxidation of ilmenite concentrate to prepare Fe–Ti alloy, Rare Met., 35(2016), No. 3, p. 275. doi: 10.1007/s12598-014-0355-7
|
| [30] |
S.L. Wang, W. Wang, S.C. Li, and S.H. Cao, Cathodic behavior of molten CaCl2−CaO and CaCl2−NaCl−CaO, Int. J. Miner. Metall. Mater., 17(2010), No. 6, p. 791. doi: 10.1007/s12613-010-0391-8
|
| [31] |
Z.R. Zhou, Y.J. Zhang, Y.X. Hua, C.Y. Xu, P. Dong, Q.B. Zhang, and D. Wang, Preparation of ferrotitanium alloys by electrolysis-assisted calciothermic reduction of ilmenite in equimolar CaCl2–NaCl electrolyte: Effect of calcium oxide, JOM, 70(2018), No. 4, p. 575. doi: 10.1007/s11837-018-2743-1
|
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