Skip to main content
SpringerLink
Log in

Application of a nonisothermal thermogravimetric method to the kinetic study of the reduction of metallic oxides: Part I. A general treatment and its application to the reduction of the oxides of molybdenum by hydrogen

  • Published:
Metallurgical Transactions B Aims and scope Submit manuscript

Abstract

A theoretical treatment to evaluate activation energies of reactions by means of nonisothermal experiments was developed. The treatment considers the case where either the surface reaction or the intraparticle diffusion could be rate-controlling. Complementary to the theoretical treat-ment, thermogravimetric experiments have been carried out under both isothermal and noniso-thermal conditions. The reduction of MoO3 to Mo was found to pass through an intermediate MoO2 phase. The rate of reduction to MoO2 seems to be controlled by surface reaction, and the activation energy obtained from isothermal studies is 205.7 kJ/mol. This is comparable to the value of 211.6 kJ/mol obtained from nonisothermal reduction studies using the present theoretical treatment. The rate of reduction to Mo appears to be influenced by gas diffusion through voids. The activation energy from isothermal studies is 85.2 kJ/mol.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. S.J. Gentry, N.W. Hurst, and A. Jones:Chem. Soc., Faraday Trans. 1, 1979, vol. 65, pp. 1688–99.

    Article  Google Scholar 

  2. O.J. Wimmers, P. Arnoldy, and A.J. Moulijn:J. Phys. Chem., 1986, vol. 90, pp. 1331–37.

    Article  Google Scholar 

  3. P. Arnoldy, O.S.L. Bruinsma, and J.A. Moulijn:J. Mol. Catal., 1985, vol. 30, pp. 111–23.

    Article  Google Scholar 

  4. P. Arnoldy, J.C.M. de Jonge, and J.A. Moulijn:J. Phys. Chem., 1985, vol. 89, pp. 4517–26.

    Article  Google Scholar 

  5. J. Szekely, J.W. Evans, and H.Y. Sohn:Gas-Solid Reaction, Academic Press, New York, NY, 1976, pp. 642–45.

    Google Scholar 

  6. B. Phillips and L.L.Y. Chang:Trans. TMS-AIME, 1965, vol. 233, pp. 1433–36.

    Google Scholar 

  7. H. Kay and B.G. Langsten:J. Met., 1964, pp. 877-81.

  8. C. Wassiliev, R. Nicolov, and M. Tschimbulev:Ann. Ecole Sup. Chim. Techn., 1967, vol. 13, p. 125.

    Google Scholar 

  9. G.C. Bond and J.B.P. Tripathi:J. Less-Common Met., 1974, vol. 36, pp. 31–40.

    Article  Google Scholar 

  10. Donald T. Hawkins and Wayne L. Worrell:Metall. Trans., 1970, vol. 1, pp. 271–73.

    Google Scholar 

  11. L. Brewer and L.H. Lamoreaux:Atomic Energy Review Special Issue, No. 7,Molybdenum: Physico-chemical Properties of Its Compounds and Alloys, International Atomic Agency, Vienna, 1980, pp. 30 and 285.

    Google Scholar 

  12. O. Bertrand and L.C. Dufour:C. R. Acad. Sci. Paris, 1974, vol. 278, pp. 315–18.

    Google Scholar 

  13. J.M. Zabala, P. Grange, and B. Delmon:C. R. Acad. Sci. Paris, 1974, vol. 279, pp. 725–28.

    Google Scholar 

  14. D.M. Chizhikov, Yu. E. Ratner, and Yu. V. Tsvetkov:Russ. Metall., (Engl. Transi.), 1970, vol. 6, pp. 5–9.

    Google Scholar 

  15. J. Orchotsky and M. Kaczenski:Mater. Sci. Eng., 1979, vol. 40, pp. 245–50.

    Article  Google Scholar 

  16. Binary Alloy Phase Diagrams, 1st ed., T.B. Massalski, ed., ASM, Metals Park, OH, 1986, p. 1613.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. Department of Theoretical Metallurgy, Royal Institute of Technology, S-100 44, Stockholm, Sweden

    Du Sichen (Research Associate) & S. Seetharaman (Professor)

Authors
  1. Du Sichen
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. S. Seetharaman
    View author publications

    You can also search for this author in PubMed Google Scholar

Rights and permissions

Reprints and permissions

About this article

Cite this article

Sichen, D., Seetharaman, S. Application of a nonisothermal thermogravimetric method to the kinetic study of the reduction of metallic oxides: Part I. A general treatment and its application to the reduction of the oxides of molybdenum by hydrogen. Metall Trans B 23, 317–324 (1992). https://doi.org/10.1007/BF02656287

Download citation

  • Received:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02656287

Keywords

Search

Navigation