1990 Volume 76 Issue 10 Pages 1688-1695
A study has been made of the partition of Mn between α-Fe2O3 crystal and sodium borate fluxes at the temperatures ranging from 800°C to 1100°C as a function of flux compositions.
The total Mn content in a-Fe2O3 is linearly related to that in flux in the range of the present T. Mn contents in both phases. The temperature dependence of the partition coefficient κT. Mn = (wt%Mn) solid/(wt%Mn)liquid was found to be positive. It was found that Mn is present as Mn3+ in α-Fe2O3 crystal and Fe and Mn in flux are present as Fe3+ and Mn2+, respectively. On the basis of the mutual interaction of the Mn3+/Mn2+ and Fe3+/Fe2+ redox pairs: Fe3+ (s)+ Mn2+ (l) = Mn3+ (s) + Fe2+ (l), the partition between solid and liquid phases with a different valency state has been discussed.