Abstract
The mechanism and kinetics of β-Ta2O5 chlorination, mixed with sucrose carbon, have been studied by a thermogravimetric technique. The investigated temperature range was 500 °C to 850 °C. The reactants and reaction residues were analyzed by scanning electronic microscopy (SEM), X-ray diffraction (XRD), and Brunauer-Emmett-Teller method for surface area (BET). The effect of various experimental parameters was studied, such as carbon percentage, temperature, chlorine partial pressure, and flow, use of the multiple sample method, and carbon previous oxidation. The carbon percentage and previous treatment have an effect on the system reactivity. The temperature has a marked effect on the reaction rate. In the 500 °C to 600 °C temperature interval, the apparent activation energy is 144 kJ/mol of oxide, while at higher temperatures, the activation energy decreases. With high chorine partial pressures, the order of reaction is near zero. The kinetic contractile plate model, X=kt, considering carbon oxidation as the controlling stage, is the one with the best fit to the experimental data. A probable mechanism for the carbochlorination of β-Ta2O5 is proposed: (1) activation of chlorine on the carbon surface, (2) chlorination of Ta2O5, (3) oxidation of carbon, and (4) recrystallization of β-Ta2O5.
Similar content being viewed by others
References
I. Barin and W. Schuler: Metall. Trans. B, 1980, vol. 11B, pp. 199–207.
D. Pasquevich, J. Andrade Gamboa, and R. Caneiro: Thermochim. Acta, 1992, vol. 209, pp. 209–22.
D. Pasquevich and V. Amorebieta: Ber. Bunsenges. Phys. Chem., 1992, vol. 96, pp. 534–41.
A. Bergholm: Trans. TMS-AIME, 1961, vol. 221, pp. 1121–29.
E. Zucherato and E. Cámara: Mineral Technology Part B, Proc. III Meting of The Southerm Hemisphere of Mineral Technology and XV Brazilian Meting on Mineral Procesing and Hidrometallurgy, 1992, São Lourenço, Mina gerais, Brazil, pp. 542–60.
F. Gennari, A. Bohé, and D. Pasquevich: Thermochim. Acta, 1997, vol. 302, pp. 53–61.
F. Gennari: Ph.D. Thesis, Universidad Nacional de La Plata, La Plata, Argentina, 1998.
O. Bicerolu and H. Gauvin: Can. J. Chem. Eng., 1980, vol. 58, pp. 357–63.
R.S. Olsen and F.E. Block: Chem. Eng. Progress Symp. Ser. 66, 1970, vol. 105, pp. 225–28.
A.W. Henderson, S.L. May, and K.B. Higbie: Ind. Eng. Chem., 1958, vol. 50, pp. 611–12.
F. Fairbrother, A.H. Cowley, and N. Scott: J. Less-Common Met., 1959, vol. 1, pp. 206–16.
R. Lind and T.A. Ingles: Report No. TN 106, United Kingdom Atomic Energy Authority, United Kingdom, 1959.
O.K. Mehra and P.K. Jena: Trans. Indian Inst. Met., 1967, vol. 20, pp. 210–13.
O.K. Mehra, K.S.Z. Hussain, and Jena, P.K.: Trans. Indian Inst. Met., 1966, vol. 19, pp. 53–256.
M. del C. Ruiz, J.A. González, and J.B. Rivarola: Can. Met. Q., 1997, vol. 36, pp. 103–10.
J.A. González, F.C. Gennari, M. del C. Ruiz, A.E. Bohé, and D.M. Pasquevich,.: Trans. Inst. Mining Metall., Sect. C: Mineral Processing Extr. Metall., 1998, vol. 103, pp. C130-C135.
J.A. González, J.B. Rivarola, D. Pasquevich, and M. del C. Ruiz: J. Mater. Sci., 1998, vol. 33, pp. 4173–80.
J. González, A. Bohé, D. Pasquevich, and M. del C. Ruiz: Can. Metall. Q., 2002, vol. 41, pp. 29–40.
E. Allain, M. Djona, and I. Gaballah: Metall. Trans. B, 1997, vol. 28B, pp. 223–33.
A. Tóth, I. Bertóti, and T. Székely: Thermochim. Acta, 1982, vol. 52, pp. 211–15.
I. Bertóti, A. Tóth, T. Székely, and Y.S. Pap: Thermochim. Acta, 1981, vol. 44, pp. 325–31.
M. Soleiman and I. Rao: Metall. Trans. B, 1987, vol. 18B, pp. 459–70.
A. Roine: Outukumpu HSC Chemistry for Windows Version 5.1, Outokumpu Research, Pori, Finland, 2003.
I. Gaballah, E. Allain, and M. Jona: in Light Metals 1994, U. Mannweiler, ed., TMS, Warrendale, PA, 1994, vol. 1, pp. 153–61.
J. González, M. del C. Ruiz, A. Bohé, and D. Pasquevich: Carbon, 1999, vol. 37, pp. 1979–88.
F. Yang and V. Hlavacek: Metall. Mater. Trans. B, 1998, vol. 29B, pp. 1297–1307.
A. Bohé and D. Pasquevich: Ver. Bunsenges. Phys. Chem., 1995, vol. 99, pp. 1553–58.
C.J. Chen and M.H. Back: Carbon, 1979, vol. 17, pp. 495–501.
P.K. Jena, E.A. Brocchi, and D.H. Gameiro: Trans. Inst. Mining Metall., Sect. C: Mineral Processing Extr. Metall., 1998, vol. 103, pp. C139-C145.
H. Tobias and A. Soffer: Carbon, 1985, vol. 23, pp. 281–89.
J. Andrade Gamboa and D.M. Pasquevich: Metall. Mater. Trans. B, 2000, vol. 31B, pp. 1439–46.
I. Gaballah, M Djona and E. Allain: Metall. Mater. Trans. B, 1995, vol. 26B, pp. 711–18.
F. Habashi: Principles of Extractive Metallurgy. General Principles, 2nd ed., Gordon and Breach Science Publishers, Inc., New York, NY, 1980, vol 1, pp. 111–69.
O.D. Quiroga, J.R. Avanza, and A.J. Fusco: Modelado Cinético de lasTtransformaciones Fluido-Sólido Reactivo, Editorial Universitaria de la Universidad Nacional del Nordeste, EUDENE, Buenos Aires, 1996.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Del C. Ruiz, M., González, J.A. & Rivarola, J.B. Kinetics of chlorination of tantalum pentoxide in mixture with sucrose carbon by chlorine gas. Metall Mater Trans B 35, 439–448 (2004). https://doi.org/10.1007/s11663-004-0045-1
Received:
Issue Date:
DOI: https://doi.org/10.1007/s11663-004-0045-1