Electronically mediated reactions in metal thermal reduction of molybdenum and tungsten oxide compounds

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Abstract


The reduction of tungsten and molybdenum oxide compounds (WO3, MoO3, MgWO4, MgMoO4, and CaMoO4) with calcium vapor at 800860°С and a residual argon pressure of 510 kPa in reactor have been studied. As previously during the reduction with magnesium vapor, the spatial separation of the reaction products was observed, namely, the major portion of the calcium oxide formed in the reaction was deposited outside the reaction zone. A specific feature of the reduction of MgWO4 and MgMoO4 is that the magnesium is first replaced by calcium. The resulting magnesium metal acts as a reducing agent, and the magnesium oxide, along with calcium oxide, forms a crust on the surface of the reaction mass. Analysis of the results shows that the reduction of oxide compounds with magnesium and calcium vapors at a residual argon pressure in reactor of more than 5 kPa proceeds via the electronically mediated reaction mechanism without direct physical contact between the reactants.


About the authors

V. N. Kolosov

Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials Kola Science Centre of the Russian Academy of Sciences

Author for correspondence.
Email: tantal@chemy.kolasc.net.ru

Russian Federation, 14, Fersman street, Apatity, Murmansk region,184209

V. M. Orlov

Institute of Chemistry and Technology of Rare Elements and Mineral Raw Materials Kola Science Centre of the Russian Academy of Sciences

Email: tantal@chemy.kolasc.net.ru

Russian Federation, 14, Fersman street, Apatity, Murmansk region,184209

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