Overview
SIST ISO 4293:2001 - Manganese ores and concentrates - Determination of phosphorus content - Extraction-molybdovanadate photometric method is an International Standard developed by ISO for the chemical analysis of manganese ores and concentrates. The standard specifies a photometric method for determining phosphorus content in manganese ore samples, utilizing an extraction-molybdovanadate approach. This analytical method is suitable for products with phosphorus concentrations ranging from 0.02% to 0.5% by mass (m/m).
The document describes the principle, required reagents, apparatus, sample preparation, procedural steps, and the calculation and expression of results. It should be used in conjunction with ISO 4297, which covers general instructions for chemical analysis of manganese ores and concentrates.
Key Topics
- Scope of Application: Applies to manganese ores and concentrates with phosphorus levels between 0.02% and 0.5% (m/m), an interval relevant for quality control in mining, refining, and materials science laboratories.
- Analytical Principle: Uses the extraction-molybdovanadate photometric method. Phosphorus is converted into a colored phosphovanadomolybdate complex, which is then measured spectrophotometrically.
- Sample Preparation: Emphasizes precise sample crushing to ≤100 μm, air drying, and specific extraction procedures to ensure reliable and accurate results.
- Chemicals and Reagents: Lists exact chemical compounds, including acids, ammonium vanadate, ammonium molybdate, and isobutyl methyl ketone, for effective separation and analysis.
- Interference Elimination: The procedure incorporates the use of citric acid to eliminate interference from elements such as iron and arsenic, enhancing accuracy.
- Measurement and Calibration: Specifies absorbance measurement at 425 nm using a spectrophotometer or photoelectric absorptiometer and outlines preparation of calibration curves for quantitative analysis.
Applications
The SIST ISO 4293:2001 standard provides significant value in several practical contexts:
- Quality Assurance in Mining: Ensures that phosphorus content in manganese ores is within acceptable limits, preventing negative impacts on downstream metallurgical processes.
- Industrial Production: Critical in the production of manganese alloys, where excessive phosphorus can impair mechanical properties and process efficiency.
- Research and Development: Supports analytical laboratories in minerals processing and materials science by delivering a validated, standardized method for phosphorus quantification.
- Trade and Compliance: Facilitates international and domestic trade of manganese ores and concentrates by providing a universally accepted testing protocol.
- Laboratory Accreditation: Assists laboratories seeking ISO certification or accreditation by detailing methodical, reproducible procedures.
Related Standards
- ISO 4297: Manganese ores and concentrates - Methods of chemical analysis - General instructions (companion guideline for overall procedures).
- ISO 4296-1: Manganese ores - Sampling - Part 1: Increment sampling.
- ISO 4296-2: Manganese ores - Sampling - Part 2: Preparation of samples.
These related standards ensure harmonized sampling, preparation, and analysis procedures for consistent application in the mining and minerals industry.
Keywords: ISO 4293, manganese ores, phosphorus determination, extraction-molybdovanadate method, photometric analysis, chemical analysis, standard, mining quality control, ore concentrate testing, ISO 4297, spectrophotometry.