Solubility of some transition metal oxides in cryolite-alumina melts: Part I. Solubility of FeO, FeAl(2)O(4), NiO, and NiAl(2)O(4)

From: Metallurgical and Materials Transactions | Date: December 1, 2002| Author: Dewing, Ernest W; Haarrberg, Geir M; Lorentsen, Odd-Arne; Thonstad, Jomar; Jentoftsen, Trond E | Copyright information

The solubilities of FeO, FeAl^sub 2^O^sub 4^, NiO, and NiAl^sub 2^O^sub 4^ were measured in cryolite-alumina melts at 1020 ^sub 6^C. FeO was found to be the stable solid phase at alumina concentrations below 5.0 wt pct, while FeAl^sub 2^O^sub 4^ was stable above that. The corresponding figure for the nickel system was 3.0 wt pct Al^sub 2^O^sub 3^. These values correspond to Gibbs energies of formation of the aluminates (from the constituent oxides) of -17.6 and -29 kJ/mol, respectively. In al...

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