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Metallurgical and Materials Transactions B

, Volume 31, Issue 4, pp 713–721 | Cite as

Contactless electrochemical reduction of titanium (II) chloride by aluminum

  • T. Uda
  • T. H. Okabe
  • Y. Waseda
  • K. T. Jacob
Article

Abstract

Because of the strong affinity between aluminum and titanium, it has not been possible to produce pure titanium by direct aluminothermic reduction of titanium chlorides. Described in this article is a new process for contactless reduction of titanium dichloride by aluminum in which titanium dichloride and the reductant (aluminum or aluminum alloy) were physically separated, but electrochemically connected through molten NaCl and an external circuit. Titanium dichloride was spontaneously reduced to metal by a cathodic reaction with the simultaneous discharge of chlorine ions into the melt. At the anode, metal aluminum was oxidized to form aluminum chloride dissolved in the molten salt. The electrons were transferred between the electrodes through the external circuit. The concentration of aluminum in titanium produced at 1223 and 1273 K varied from values below the detection limit of the X-ray fluorescence analysis (0.01 mass pct) to 4.5 mass pct. The average contamination was 0.76 mass pct Al. When an aluminum-nickel alloy was used as the reductant, nickel was not detected in the titanium obtained by reduction. This observation suggests that aluminum scrap may be used as a cheap reductant in this contactless electrochemical process.

Keywords

Material Transaction TiCl Molten Salt External Circuit Metal Titanium 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    W. Kroll: Tr. Electrochem. Soc., 1940, vol. 78, pp. 35–47.Google Scholar
  2. 2.
    D.R. Sadoway and T.H. Okabe: Massachusetts Institute of Technology, Technology Disclosure, O.S.P. Project No.61243, MIT, Cambridge, MA, 1994.Google Scholar
  3. 3.
    T.H. Okabe and D.R. Sadoway: J. Mater. Res., 1998, vol. 13, pp. 3372–77.Google Scholar
  4. 4.
    T. Uda, T.H. Okabe, E. Kasai, and Y. Waseda: J. Jpn. Inst. Met., 1997, vol. 61, pp. 602–09.Google Scholar
  5. 5.
    T.H. Okabe, T. Uda, E. Kasai, and Y. Waseda: J. Jpn. Inst. Met., 1997, vol. 61, pp. 610–18.Google Scholar
  6. 6.
    t.H. Okabe and Y. Waseda: J. Met., 1997, vol. 49(6), pp. 28–32.Google Scholar
  7. 7.
    T. Uda, T.H. Okabe, and Y. Waseda: J. Jpn. Inst. Met., 1998, vol. 62, pp. 76–84.Google Scholar
  8. 8.
    T. Uda, T.H. Okabe, and Y. Waseda: J. Jpn. Inst. Met., 1998, vol. 62, pp. 796–802.Google Scholar
  9. 9.
    T. Uda, T.H. Okabe, Y. Waseda, and K.T. Jacob: J. Alloys Compounds, 1999, vol. 284, pp. 282–288.CrossRefGoogle Scholar
  10. 10.
    T.H. Okabe, T. Uda, and Y. Waseda: J. Min. Mater. Processing Inst. Jpn., 1998, vol. 114, pp. 573–79.CrossRefGoogle Scholar
  11. 11.
    F. Zhang, S.L. Chen, Y.A. Chang, and U.R. Kattner: Intermetallics, 1997, vol. 5, pp. 471–82.CrossRefGoogle Scholar
  12. 12.
    T. Yahata, T. Mitsugi, and M. Maeda: CAMP-ISIJ (Proc. Iron Steel Inst. Jpn.), 1990, vol. 3, p. 1646.Google Scholar
  13. 13.
    G.W. Fletcher: U.S. Patent No. 4,169,722, 1979.Google Scholar
  14. 14.
    J. Kamlet: U.S. Patent No. 2837426, 1958.Google Scholar
  15. 15.
    T. Kumagai, S. Konda, T. Sasaki, and T. Ishikawa: Denki Kagaku, 1996, vol. 64, pp. 296–300.Google Scholar
  16. 16.
    Q. Zhuxian, Z. Minglie, Y. Xaxin, C. Zhenghan, K. Grjothim, and H. Kvande: Aluminium, 1988, vol. 64, pp. 606–09.Google Scholar
  17. 17.
    M. Maeda, T. Kiwake, K. Shibuya, and T. Ikeda: Mater. Sci. Eng. A, 1997, vols. 239–240, pp. 276–80.Google Scholar
  18. 18.
    Thermochemical Properties of Inorganic Substances, O. Knacke, O. Kubaschewski, and K. Hesselmann, eds., Springer-Verlag, Berlin, 1991.Google Scholar
  19. 19.
    O. Kubaschewski and W.A. Dench: J. Inst. Met., 1953–54, vol. 82, pp. 87–91.Google Scholar
  20. 20.
    K.L. Komarek and M. Silver: Proc. IAEA Symp., Thermodynamics of Nuclear Materials, IAEA, Vienna, 1962, pp. 749–74.Google Scholar
  21. 21.
    T.H. Okabe, R.O. Suzuki, T. Oishi, and K. Ono: Mater. Trans. JIM, 1991, vol. 32, pp. 485–88.Google Scholar
  22. 22.
    G.J. Janz: Molten Salts Handbook, Academic Press, New York, NY, 1967.Google Scholar
  23. 23.
    Binary Alloy Phase Diagrams, 2nd ed., T.B. Massalski, ed., ASM, Materials Park, OH, 1990.Google Scholar
  24. 24.
    R. Sailer and G. McCathy: Joint Committee on Powder Diffraction Standards (JCPDS) Card No. 44-1294, International Centre for Diffraction Data, Newtown Square, PA, 1993.Google Scholar
  25. 25.
    H. Linga, K. Motzfeldt, and H.A. Øye: Ber. Bunsenges. Phys. Chem., 1978, vol. 82, pp. 568–76.Google Scholar
  26. 26.
    S.N. Flengas: Ann. N.Y. Acad. Sci., 1960, vol. 79, pp. 853–72.CrossRefGoogle Scholar
  27. 27.
    V.S. Maksimov and M.V. Smirnov: Electrochem. Mol. Sol. Electrolytes, 1968, vol. 6, pp. 30–36.Google Scholar

Copyright information

© ASM International & TMS-The Minerals, Metals and Materials Society 2000

Authors and Affiliations

  • T. Uda
    • 1
  • T. H. Okabe
    • 2
  • Y. Waseda
    • 2
  • K. T. Jacob
    • 3
  1. 1.Institute for Advanced Materials ProcessingTohoku UniversityJapan
  2. 2.the Institute for Advanced Materials ProcessingTohoku UniversitySendaiJapan
  3. 3.Department of MetallurgyIndian Institute of ScienceBangaloreIndia

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