ISO 5416:2006 PDF

Overview

ISO 5416:2006 specifies a bromine–methanol titrimetric method for the determination of the mass fraction of metallic iron in direct reduced iron (DRI). The procedure is applicable to DRI samples with metallic iron content between 15 % and 95 %. The standard describes sampling/preparation, required reagents and apparatus, the dissolution and titration procedure, calculation of results (including moisture correction and blank correction), and reporting requirements.

Key topics and technical requirements

• Scope and applicability: Quantitative determination of metallic iron in DRI (15–95 % mass fraction).
• Analytical principle: Metallic iron is dissolved with a freshly prepared bromine–methanol solution; insoluble residue is removed by filtration. Iron in the filtrate is reduced to Fe(II) and titrated with potassium dichromate after reduction with tin(II) chloride.
• Reagents and solutions: Bromine–methanol (50 ml/l), hydrochloric and sulfuric acids, hydrogen peroxide, tin(II) chloride, mercury(II) chloride, iron standard, and potassium dichromate volumetric solution. Use analytical-grade reagents and water per ISO 3696.
• Apparatus: Standard volumetric glassware (burette, pipettes, volumetric flasks), 100 ml conical flask, magnetic stirrer, and filtration with glass-fibre or microfilters (pore