フェライト中の鉄定量方法の検討および錯塩滴定法による鉄，マンガン，亜鉛迅速定量方法

Abstract

Critical studies were made of various methods for determination of iron and rapid complexometry of iron, manganese and zinc in ferrite were carried out. The results obtained are as follows: (1) The liquid zinc amalgam reduction-KMnO4 titration method produces Mn++ at the end point in the case of large amounts of KMnO4 titre and gives positive error. Use of diphenylamine indicator gives accurate results. (2) The photochemical reduction by oxalic acid-H3VO4 titration method is accurate and simple even on large when the concentration of iron is large. (3) In SnCl2 reduction-H3VO4 titration method, the color changes of diphenylamine at the end point is made very sharp by addition of oxalic acid and it gives accurate results even with large amounts of H3VO4 titre. (4) Sodium azide and naphthol green B or malachite green mixture are good indicators in complexometry of ferric iron containing manganese and zinc. (5) Rapid simultaneous complexometry of manganese and zinc in Mn-Zn-ferrite is described.