Overview
ISO 15633:2017 specifies a flame atomic absorption spectrometric (FAAS) method for the determination of the nickel mass fraction in iron ores. It covers natural iron ores, concentrates and agglomerates (including sinter) for nickel mass fractions between 0.001 % and 0.10 %. The method is intended for routine analytical use (not appropriate for referee/arbitration purposes) and includes sample preparation, chemical decomposition, iron removal, instrument calibration and calculation of results.
Key topics and technical requirements
- Scope and range: Nickel determination in iron ores from 0.001 % to 0.10 % (mass fraction).
- Sample preparation:
- Use a laboratory sample of −100 µm particle size (or −160 µm for ores with significant combined water/oxidizable compounds).
- Prepare predried test samples dried at 105 °C ± 2 °C per ISO 7764.
- Test portion ≈ 1 g, weighed to 0.0002 g precision.
- Chemical decomposition and treatment:
- Test portion decomposed by hydrochloric and nitric acid.
- Major iron removed by extraction with 4‑methylpentan‑2‑one (MIBK).
- Insoluble residue ignited; SiO2 removed with hydrofluoric and sulfuric acid; residue fused with sodium carbonate/sodium tetraborate (or lithium tetraborate) and recombined with main solution.
- Reagents and standards:
- Use analytical-grade reagents and Grade 2 water (ISO 3696).
- Nickel standard solutions: 100 µg Ni/ml (A) and 10 µg Ni/ml (B) for calibration.
- Instrumentation and performance criteria:
- Atomic absorption spectrometer with an air‑acetylene burner.
- Minimum absorbance for highest calibration solution: ≥ 0.3.
- Linearity and stability requirements (specified slope and standard deviation limits) to ensure reliable FAAS performance.
- Example instrument settings provided (e.g., wavelength 232.0 nm; hollow‑cathode lamp 10 mA; air/acetylene flow guidelines).
- Quality control:
- Run blanks and a certified reference material (same ore type) in each batch.
- Minimum duplicate determinations and guidance on repeatability, precision and reporting.
Applications and users
ISO 15633:2017 is suited for:
- Metallurgical and mining laboratory quality-control testing of iron ores and concentrates.
- Plant/process control, purchase/specification testing, and routine analytical workflows.
- Laboratories performing chemical analysis of ores that require reproducible nickel determinations at low concentrations.
Note: Because the method is not a referee method, it is not recommended for arbitration or legal disputes.
Related standards
- ISO 3082 - Sampling and sample preparation for iron ores
- ISO 7764 - Preparation of predried test samples
- ISO 2596 - Hygroscopic moisture determination (when applicable)
- ISO 3696, ISO 648, ISO 1042 - Laboratory water and glassware specifications
Keywords: ISO 15633:2017, iron ores, nickel determination, flame atomic absorption spectrometry (FAAS), nickel mass fraction, ore analysis, MIBK extraction, sample preparation, analytical method.