Overview
ISO 26482:2010 - Hardmetals - Determination of lead and cadmium content defines a validated chemical and instrumental procedure for measuring lead (Pb) and cadmium (Cd) in hardmetals (cemented carbides). The standard covers sample digestion, separation/concentration of Pb and Cd, and quantitative analysis by flame atomic absorption spectrometry (FAAS/AAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES/ICP). It applies to products with Pb and Cd mass fractions from 0.0001 % to 0.1 % (1 mg/kg to 1 000 mg/kg).
Key topics and technical requirements
- Scope and limits: Applicable concentration range 0.0001–0.1 % (mass fraction) for Pb and Cd in hardmetals.
- Sample preparation: Dissolution using nitric and hydrofluoric acids, perchloric acid treatment, neutralization and removal of tungstic precipitate with sodium hydroxide.
- Separation & masking: Residual cobalt is masked using potassium cyanide (KCN); Pb and Cd are selectively extracted with dithizone in chloroform to concentrate the analytes and reduce matrix effects.
- Instrumentation & wavelengths:
- AAS (FAAS) wavelengths: Pb 283.3 nm, Cd 228.8 nm; use a fuel-lean air/acetylene flame.
- ICP wavelengths: Pb 220.3 nm, Cd 228.8 nm.
- Calibration & quantification: Preparation of mixed Pb/Cd standards (100 µg/ml) and multi-point calibration (0, 1, 3, 5 ml to 100 ml flasks) for plotting calibration curves before sample measurement.
- Quality control: Carry out reagent blanks, parallel blank tests, and follow reporting requirements (sample ID, method reference, results, analytical line, unusual features).
- Reagents & apparatus: Specifies analytical-grade reagents (HF, HNO3, HClO4, KCN, dithizone) and common lab glassware per ISO 385/648/1042; ICP-AES and FAAS instruments must be optimized per manufacturers’ instructions.
Practical applications and users
- Who uses it: Materials testing laboratories, cemented carbide (hardmetal) manufacturers, quality control/assurance teams, regulatory and compliance laboratories checking heavy-metal contamination.
- Why use it: Ensures reliable trace-level determination of Pb and Cd in hardmetal products for product quality, supplier control, environmental compliance and health/safety assessment.
- Benefits: Reduces matrix interferences through solvent extraction and masking, provides validated reproducibility data (annex includes inter-laboratory and repeatability results), and supports consistent reporting.
Related standards
Keywords: ISO 26482:2010, hardmetals, lead determination, cadmium determination, FAAS, ICP-AES, dithizone extraction, sample digestion, KCN masking, trace analysis.
