Overview
ISO 5418-1:2006 specifies a chemical analytical procedure - the 2,2′-biquinolyl spectrophotometric method - for the determination of copper in iron ores. The method is intended for natural iron ores, concentrates and agglomerates (including sinter) with copper mass fractions from 0.005% to 0.77%. It defines the principle, required reagents and apparatus, sampling and sample preparation, test procedure, expression of results, precision guidance and reporting requirements.
Key topics and technical requirements
- Analytical principle: acid decomposition of a test portion, removal/dehydration of silica, fusion of residue, reduction of Cu(II) to Cu(I) with ascorbic acid and formation of a red‑violet copper(I) complex with 2,2′-biquinolyl, measured spectrophotometrically at ≈545 nm.
- Scope & measurement range: applicable to copper mass fractions 0.005%–0.77% in various iron ore matrices.
- Reagents & purity: prescribes analytical-grade reagents (e.g., HCl, HNO3, HClO4, HF, H2SO4), N,N‑dimethylformamide, ascorbic acid and prepared 2,2′-biquinolyl solution; includes guidance on copper‑free glassware and water (ISO 3696 grade 3).
- Apparatus: common lab glassware complying with ISO 648/1042, platinum crucible, muffle furnace (to ~1 000 °C) and a spectrophotometer capable of measurements near 545 nm.
- Sampling & sample prep: references ISO 3082 and ISO 7764 for sampling, particle-size recommendations (typically −100 µm or −160 µm depending on ore characteristics) and predrying at 105 °C ±2 °C.
- Quality control & precision: requires blank tests, analysis of certified reference materials, duplicate independent determinations and provides guidance on repeatability, between‑laboratory precision and acceptance of analytical values.
- Safety note: involves hazardous acids and volatile fluorides; the standard warns users to adopt appropriate health and safety practices.
Applications and users
- Practical for mining and metallurgical laboratories, quality control (QC) in ore processing plants, commodity testing laboratories and organizations verifying feedstock for steelmaking.
- Used to: quantify copper impurities in iron ores/concentrates, support product specification compliance, inform beneficiation decisions and provide reference data for contractual testing.
- Beneficial where spectrophotometric alternative to atomic absorption is preferred for the specified concentration range.
Related standards
Keywords: ISO 5418-1:2006, iron ores, copper determination, 2,2′-biquinolyl, spectrophotometric method, ore analysis, analytical chemistry, laboratory procedure.