Determination of Fe2+ and Mn3+ in the mixture of iron, manganese and zinc oxides: Determination of Fe2+ and Mn3+ in sintered Mn-Zn ferrites. III

Fe2+ and Mn3+ in oxide mixtures iron, manganese and zinc were spectrophotometrically determined. The method included two procedures: (a) the sample was dissolved in hot polyphosphoric acid containing a definite amount of Mn3+ and (b) the sample was dissolved in hot H3PO4-HClO4 (30+1) mixture. Absorbancies at 520 mμ corresponding to Mn3+ were measured on both (a) and (b) solutions. The values for (a) compared with blank value represented the difference between Mn3+ and Fe2+ in the sample, and the value for (b) corresponded to the amount Mn3+-(z-B) where z was consumed amount of Mn3+ by Mn3+_??_Fe2+ reaction, and B represented the amount of Mn3+ formed by the oxidation of MnO in the sample. The relation between z-B, a, b, and Mn3+ / Fe2+ was investigated extensively on standard samples. Fe2+ and Mn3+ in easily or difficultly soluble oxide mixtures and Mn-Zn ferrites were determined successfully by this means in good accuracy.