Hostname: page-component-7b7567c8c-7pwfn Total loading time: 0 Render date: 2026-11-14T19:26:33.461Z Has data issue: false hasContentIssue false
  • English
  • Français

Metallothermic reduction as an electronically mediated reaction

Published online by Cambridge University Press:  31 January 2011

Toru H. Okabe and
Donald R. Sadoway
Toru H. Okabe
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139–4307
Donald R. Sadoway
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139–4307
Get access

Abstract

The commonly held view that metallothermic reduction is strictly a chemical reaction and that the process is rate limited by mass transfer has been found to be incomplete. In a study of the production of tantalum powder by the reaction of K2TaF7 with sodium, it has been shown that there are two dominant kinetic pathways, both involving electron transfer. Furthermore, the overall rate of reaction is limited by electron transport between the reactants. This indicates that metallothermic reduction is an “electronically mediated reaction” (EMR). Experiments found that the location of the tantalum deposit and its morphology are governed by the reaction pathway.

Information

Type
Articles
Information
Journal of Materials Research , Volume 13 , Issue 12 , December 1998, pp. 3372 - 3377
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

1.Gupta, C. K., Int. Met. Rev. 29, 405 (1984).CrossRefGoogle Scholar
2.Jain, S. C., Bose, D. K., and Gupta, C. K., Trans. Indian Inst. Met. 24, 1 (1971).Google Scholar
3.Konstantinov, V. I., Polyakov, E. G., and Stangrit, P. T., Electrochim. Acta 23, 713 (1978).CrossRefGoogle Scholar
4.Taxil, P. and Mahenc, J., J. Appl. Electrochem. 17, 261 (1987).CrossRefGoogle Scholar
5.Kock, W. and Paschen, P., Metall. 44, 928 (1990).Google Scholar
6.Espinola, A., Dutra, A. J. B., and Silva, F. T., Anal. Chim. Acta 251, 53 (1991).CrossRefGoogle Scholar
7.Polyakova, L. P., Polyakov, E. G., Soronkin, A. I., and Stangrit, P. T., J. Appl. Electrochem. 22, 628 (1992).CrossRefGoogle Scholar
8.Lantelme, F., Barhoun, A., Li, G., and Besse, J-P., J. Electrochem. Soc. 139, 1249 (1992).CrossRefGoogle Scholar
9.Voyiatzis, G. A., Pavlatou, E. A., Papatheodorou, G. N., Bachtler, M., and Freyland, W., in Molten Salt and Technology 1993, edited by Saboungi, M-L. and Kojima, H. (The Electrochem. Soc. Symp. PV 93–9, Pennington, NJ, 1993), p. 252.Google Scholar
10.Chen, G-S., Edwards, A. G., and Mamantov, G., J. Electrochem. Soc. 140, 2439 (1993).CrossRefGoogle Scholar
11.Bachtler, M., Rochengerger, J., Freyland, W., Rosenkilde, C., and Østvold, T., J. Phys. Chem. 98, 742 (1994).CrossRefGoogle Scholar
12.Marinina, L. K., Rakov, E. G., Gromkov, B. V., and Markina, O. V., Zh. Fiz. Khim. 45, 1592 (1971).Google Scholar
13.Amosov, V. M., Izv. Vysshikh Ucheb. Zavdenii, Tsvetn. Met. 7 (3), 123 (1964).Google Scholar
14.Kroll, W. J., Trans. Electrochem. Soc. 78, 35 (1940).CrossRefGoogle Scholar
15.Krumpelt, M., Fischer, J., and Johnson, I., J. Phys. Chem. 72, 506 (1968).CrossRefGoogle Scholar
16.Warren, W. W., Jr., in Molten Salt Chemistry, An Introduction and Selected Applications, edited by Mamantov, G. and Marassi, R. (D. Reidel Publishing Co., Boston, MA, 1986), p. 237.Google Scholar
17.Hunter, M. A., J. Am. Chem. Soc. 32, 330 (1910).CrossRefGoogle Scholar
18.Bredig, M. A., in Molten Salt Chemistry, edited by Blander, M. (Interscience, New York, 1964), p. 367.Google Scholar