ISO 9517:2007 PDF

Overview

ISO 9517:2007 - "Iron ores - Determination of water‑soluble chloride - Ion‑selective electrode method" specifies a potentiometric procedure to determine the mass fraction of water‑soluble chloride in iron ores, concentrates and agglomerates (including sinter). The method is applicable to the range 0.007 % to 0.1 % water‑soluble chloride and defines the sampling, sample preparation, reagents, apparatus and calculation rules required for reliable chloride determination.

Key topics and technical requirements

• Analytical principle: Leaching of a predried test portion in water with potassium sulfate, filtration and potentiometric measurement with a chloride ion‑selective electrode (ISE) and a double‑junction reference electrode after addition of phosphate buffer, potassium persulfate (oxidant) and an ionic‑strength adjuster (sodium nitrate).
• Measurement range: Valid for 0.007 % to 0.1 % water‑soluble chloride in natural iron ores and derived products.
• Calibration: Preparation of calibration solutions (examples: 2, 3, 5, 10, 25, 50 µg Cl−/ml) using defined standard solutions; low‑level calibrations (2–10 µg/ml) should be prepared on the day of use.
• Apparatus and consumables: Chloride ISE and separate double‑junction reference electrode (combined electrodes not suitable), high‑impedance meter with 0.1 mV sensitivity, microfilters (cellulose membrane,