Content Handbook L

Outline of method

95.1 Total iron

95.1.1 Oxidation of divalent iron

The iron present is reduced to divalent iron with a silver reductor, and divalent iron is titrated with cerium(IV) sulphate using ferroin sulphate as indicator.

95.1.2 Reduction of trivalent iron.

The divalent iron present is oxidized with an excess of potassium permanganate and the solution is boiled to destroy the excess. The solution is then titrated with titanium(III) sulphate using ammonium thiocyanate as indicator.

95.1.3 EDTA

The iron is titrated with EDTA using salicylic acid in acetone as indicator.

95.2 Divalent iron

The divalent iron is titrated with cerium(IV) sulphate solution using ferroin sulphate as indicator.

Scope

95.1 Total iron

95.1.1 Oxidation of divalent iron

The method determines total iron. The silver reductor has been chosen for use because it is less subject to interferences than many other methods and gives accurate results.