Abstract
Data are presented on the formation sequence of metallic, carbide, and intermediate oxide phases in the carbon reduction of CoWO4 and NiWO4. The surface reaction between CoWO4 particles and solid carbon yields the mixed carbide Co6W6C, while the reaction with the CO originating from carbon vaporization yields the intermetallic phase Co7W6. The initial stage of the solid-state and gas-phase reduction of NiWO4 yields a solid solution of tungsten in nickel (∼10 at % W), Ni4W, and, presumably, the NiWO4-WO3 eutectic. The solid solution reacts with carbon to form Ni2W4C and with CO to form filamentary tungsten crystals.
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Original Russian Text © N.V. Lebukhova, N.F. Karpovich, 2006, published in Neorganicheskie Materialy, 2006, Vol. 42, No. 3, pp. 357–362.
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Lebukhova, N.V., Karpovich, N.F. Carbothermic reduction of cobalt and nickel tungstates. Inorg Mater 42, 310–315 (2006). https://doi.org/10.1134/S0020168506030174
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DOI: https://doi.org/10.1134/S0020168506030174