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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
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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.

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

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