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Equilibria in the silicothermic reduction of calcined dolomite

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Abstract

When a mixture of calcium oxide and silicon is heated to above 1000°C a liquid Ca-Si alloy is formed. When magnesium metal is produced by reacting calcined dolomite with silicon, the alloy still forms and is the effective reducing agent for magnesium oxide. In this investigation the thermodynamic data on the Ca-Si alloys have been related to the magnesiumproducing reaction, the calcium pressures over mixtures CaO + Si were measured using a Knudsen cell, and the magnesiumand calcium pressures over the mixtures CaO + MgO + Si were measured using the transportation method. The magnesium content of the equilibrium alloy was determined isopiestically and the identity of the silicate was established. The results constitute a complete and consistent definition of the equilibria in the magnesium production reaction, and have also yielded an improved value of thefree energy of formation of calcium orthosilicate.

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References

  1. L. M. Pidgeon and W. A. Alexander:Trans. AIME, 1944, vol. 159, p. 315; L. M. Pidgeon:Trans. Can. Inst. Min. Met, 1944, vol. 47, p. 16.

    Google Scholar 

  2. A. Schneider:Metall. Erz., 1942, vol. 39, p. 272.

    CAS  Google Scholar 

  3. C. Faure and J. Marchall:J. Metals, 1964, vol. 16, p. 721.

    CAS  Google Scholar 

  4. A. Schneider, J. F. Cordes, H. Kribbe, and H. Runge:Z. Erzbergbau Mettalhuettenw., 1959, vol. 12, pp. 193, 164,224.

    Google Scholar 

  5. L. M. Pidgeon and J. A. King:Discussions Faraday Soc, 1948, vol. 4, p. 197.

    Article  Google Scholar 

  6. A. Schneider and E. Hesse:Z. Elektrochem., 1940, vol. 46, p. 279.

    CAS  Google Scholar 

  7. J. M. Toguri and L. M. Pidgeon:Can. J. Chem., 1961, vol. 39, p. 540,Can. J. Chem., 1962, vol. 40, p. 1769.

    Article  CAS  Google Scholar 

  8. H. Kautsky and H. Thiele:Z. Anorg. Allgem. Chem., 1928, vol. 173, p. 121; also L. Woller and W. Schuff,Z. Anorg. Allgem. Chem., 1932, vol. 209, p. 33.

    Article  Google Scholar 

  9. J. E. Ricci:Phase Rule and Heterogeneous Equilibrium, Dover, New York, 1966.

    Google Scholar 

  10. J. R. Wynnyckyj and L. M. Pidgeon:Met. Trans., 1971, vol. 2, p. 975.

    CAS  Google Scholar 

  11. O. Kubaschewski and E. L. Evans:Metallurgical Thermochemistry, p. 375, Pergamon, London, 1958.

    Google Scholar 

  12. J. Chipman:PureAppl. Chem., 1962, vol. 5, p. 361.

    Google Scholar 

  13. M. Hansen: Constitution of Binary Alloys, 2nd ed., McGraw-Hill, New York, 1958.

    Google Scholar 

  14. J. M. Eldridge, E. Miller, and K. L. Komarek:Trans. TMS-AIME, 1967, vol. 239, p. 775.

    CAS  Google Scholar 

  15. W. T. Hughes, C. E. Ransley, and E. F. Emley: inAdvances in Extractive Metallurgy, Inst. Min. Met., London, 1968.

  16. M. F. Goudge:Limestones of Canada, Queen’s Printer, Ottawa.

  17. J. R. Wynnyckyj and L. M. Pidgeon:Can. Met. Quart, 1971, vol. 9.

  18. W. Eitel:Physical Chemistry of the Silicates, p. 260, McGraw-Hill, New York, 1953.

    Google Scholar 

  19. J. F. Elliott and M. Gleiser:Thermochemistry of Steelmaking, vol. I, 1960, and vol. II, 1962, Addison Wesley, Reading, Mass.

    Google Scholar 

  20. S. S. Wise, J. L. Margrave, H. M. Fedder, and W. M. Hubbard:J. Phys. Chem., 1962, vol. 66, p. 381, W. D. Good:J. Phys. Chem., 1962, vol. 66, p. 480.

    Article  CAS  Google Scholar 

  21. R. Hultgren, R. L. Orr, P. B. Anderson, and K. K. Kelley:Selected Values of Thermodynamic Properties of Metals and Alloys, John Wiley & Sons, New York, 1963!

    Google Scholar 

  22. B. Ellingsaeter and T. Rosenqvist:J. Metals, 1956, vol. 8, p. 1111.

    CAS  Google Scholar 

  23. K. Johanssen: Thesis, Inst. Inorg. Chem., Norwegian Inst. of Technology, Trondheim, 1967.

    Google Scholar 

  24. W. J. Thoburn: M. A. Sei. Thesis, University of Toronto, 1962. S. Wilkening: M. A. Sci. Thesis, University of Toronto, 1960.

  25. E. J. Huber and C. E. Holley:J. Phys. Chem., 1956, vol. 60, p. 498; L. Brewer:Chem. Rev., 1953, vol. 52, p. 1.

    Article  CAS  Google Scholar 

  26. L. S. Darken and R. W. Gurry:Physical Chemistry of Metals, p. 260, McGraw-Hill, New York, 1953.

    Google Scholar 

  27. R. Benz and C. Wagner:J. Phys. Chem., 1961, vol. 65, p. 1308.

    Article  CAS  Google Scholar 

  28. G. G. Charette and S. N. Flengas:J. Electrochem. Soc, 1968, vol. 115, p. 796.

    Article  CAS  Google Scholar 

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Authors and Affiliations

  1. Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario

    J. R. Wynnyckyj (Associate Professor)

  2. Department of Metallurgy and Materials Science, University of Toronto, Canada

    L. M. Pidgeon (Professor)

Authors
  1. J. R. Wynnyckyj
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  2. L. M. Pidgeon
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Formerly Graduate Student, University of Toronto, Toronto, Ontario, Canada.

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Wynnyckyj, J.R., Pidgeon, L.M. Equilibria in the silicothermic reduction of calcined dolomite. Metall Trans 2, 979–986 (1971). https://doi.org/10.1007/BF02664228

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  • DOI: https://doi.org/10.1007/BF02664228

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