A study has been made of the partition of Mn between α-Fe
2O
3 crystal and sodium borate fluxes at the temperatures ranging from 800 to 1100°C as a function of flux compositions.
The total Mn content in α-Fe
2O
3 is linearly related to that in flux in the studied concentration range. The temperature dependence of the partition coefficient
kT, Mn=(wt%Mn)
solid/(wt%Mn)
liquid was found to be positive. It was found that Mn is present as Mn
3+ in α-Fe
2O
3 crystal and Fe and Mn in flux are present as Fe
3+ and Mn
2+, respectively. On the basis of the mutual interaction of the Mn
3+/Mn
2+ and Fe
3+/Fe
2+ redox pairs: Fe
3+(
s)+Mn
2+(
l)=Mn
3+(
s)+Fe
2+(
l), the partition between solid and liquid phases with a different valency state has been discussed.
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