Rapid Determination of the Total Iron in Manganese Ore by Titanium Trichloride-Potassium Dichromate Titrimetric Method

The sample was dissolved,adding hydrochloride acid to converted the iron to FeCl3,adding SnCl2 to convert most of the Fe3+ to Fe2+,adding excess TiCl3 to convert the remanent Fe3+ to Fe2+,the excess TiCl3 was oxidized by O2 dissolved in solution with copper sulfate as catalyst to eliminate its effect to the accuracy. In the sulfuric-phosphoric mixed acid,the total iron content was titrated by potassium dichromate standard solution with sodium diphenylamine sulfonate as indicator and the results were satisfactory.