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The mechanism of ferrite formation from iron sulfides during zinc roasting

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Abstract

The formation of zinc ferrite (ZnFe2O4) during the fluidized-bed roasting of zinc concentrates presents subsequent processing difficulties both for zinc recovery and for iron separation and disposal. A major source of iron in these concentrates is from the iron sulfides — pyrite and pyrrhotite. This study examined the changes undergone by these iron minerals when roasted together with sphalerite at 1223 K in a fluidizing gas mixture of 3 pct oxygen and 97 pct nitrogen. Optical microscopy and electron microprobe analysis were employed to identify the three stages that lead to ferrite formation and to examine the processes that occur within each stage. The first stage is oxidation of the sulfides to highly vesicular, amorphous magnetite particles containing small amounts of zinc. The second stage involves both densification of these particles by sintering and counterdiffusion of iron and zinc cations to form a continuous phase of homogeneous zinc-rich spinel and a precipitate of hematite. In the third stage, continuation of cation diffusion and increasingPo 2 results in the formation of stoichiometric zinc ferrite. These observations have been interpreted by reference to the established phase relationships that occur in the Zn-Fe-O system, and a detailed, solid state reaction mechanism for the formation of zinc ferrite has been proposed.

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References

  1. S. W. K. Morgan:Zinc and Its Alloys and Compounds, John Wiley and Sons, New York, NY, 1985, pp. 117–24.

    Google Scholar 

  2. J. Kruger and R. Pullenberg:Erzmetall, 1980, vol. 33, pp. 70–76.

    Google Scholar 

  3. J.W. Graydon and D. W. Kirk:Metall. Trans. B, 1988, vol. 19B, pp. 141–46.

    Article  ADS  CAS  Google Scholar 

  4. P. G. Thornhill and L. M. Pidgeon:J. of Metals, 1957, vol. 9, pp. 989–95.

    CAS  Google Scholar 

  5. F. R.A. Jorgenson:Trans. Instn. Min. Metall., Sect. C, 1981, vol. 90, pp. C1-C9.

    Google Scholar 

  6. F. R. A. Jorgenson:Australia/Japan Extractive Metallurgy Symposium, 1980, The Australasian Institute of Mining and Metallurgy, Victoria, Australia, pp. 41–51.

    Google Scholar 

  7. H. Hattori, J. Miyatani, Z. Asaki, and Y. Kondo:Australia/Japan Extractive Metallurgy Symposium, 1980, The Australasian Institute of Mining and Metallurgy, Victoria, Australia, pp. 223–32.

    Google Scholar 

  8. M. Benlyamani and F. Ajersch:Metall. Trans. B, 1986, vol. 17B, pp. 647–56.

    Article  ADS  CAS  Google Scholar 

  9. A. J. Naldrett:J. Petrol., 1969, vol. 10, pp. 171–201.

    CAS  Google Scholar 

  10. R. L. Benner and H. Kenworthy: Bur. Mines RI 6754, 1966, 44 pp.

  11. K. Fitzner:Thermochimka Acta, 1979, vol. 31, pp. 227–36.

    Article  CAS  Google Scholar 

  12. I. Katayama, J. Shibata, M. Aoki, and Z. Kozuka:Trans. Jap. Inst. Met., 1977, vol. 18, pp. 743–49.

    CAS  Google Scholar 

  13. S. C. Schaefer and R. A. McCune:Metall. Trans. B, 1986, vol. 17B, pp. 515–21.

    Article  ADS  Google Scholar 

  14. G. P. Popov, M. I. Simonova, T. A. Ugolnikova, and G. I. Chufavov:Doklady Akad. Nauk S.S.S.R., 1963, vol. 148, pp. 357–60.

    CAS  Google Scholar 

  15. Y. D. Tretyakov:Termodinamika Ferritov, Izdat. Khim. Leningrad. Otdel., 1967.

    Google Scholar 

  16. G. C. Kuczynski:Ferrites: Proceedings of the International Conference, July 1970, Japan, University Park Press, Tokyo, 1971, pp. 87–94.

    Google Scholar 

  17. G.A. Kolta, S.Z. El-Tawil, A. A. Ibrahim, and N. S. Felix:Thermochimka Acta, 1980, vol. 36, pp. 359–66.

    Article  CAS  Google Scholar 

  18. R. Parker, C.J. Rigden, and C.J. Tinsley:Trans. Faraday Soc, 1969, vol. 65, pp. 219–24.

    Article  CAS  Google Scholar 

  19. R.E. Carter, W. L. Roth, and C.A. Julien:J. Am. Ceram. Soc., 1959, vol. 42, pp. 533–36.

    Article  CAS  Google Scholar 

  20. T. Yamaguchi and T. Kimura:J. Am. Ceram. Soc., 1976, vol. 59, pp. 333–35.

    Article  CAS  Google Scholar 

  21. T. Kimura, S. Ohishi, and T. Yamaguchi:J. Am. Ceram. Soc, 1979, vol. 62, p. 533.

    Article  CAS  Google Scholar 

  22. V.I. Yaryginet al.Izv. Akad. Nauk S.S.S.R. Metally, 1986, (1), pp. 25-30.

  23. A.G. Plant: Short Course in Microbeam Techniques, Mineralogical Association of Canada, 1976, pp. 107-34.

  24. A. Ünal and A.V. Bradshaw:Metall. Trans. B, 1983, vol. 14B, pp. 743–52.

    Article  ADS  Google Scholar 

  25. F. N. Rhines:Phase Diagrams in Metallurgy, McGraw-Hill Book Company, Inc., New York, NY, 1956, pp. 45–47.

    Google Scholar 

  26. R. Lindner:Acta Chem. Scand., 1952, vol. 6, pp. 457–67.

    Article  CAS  Google Scholar 

  27. R. Lindner:Arkiv Kemi, 1952, vol. 4, pp. 381–84.

    CAS  Google Scholar 

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Graydon, J.W., Kirk, D.W. The mechanism of ferrite formation from iron sulfides during zinc roasting. Metall Trans B 19, 777–785 (1988). https://doi.org/10.1007/BF02650197

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