Overview
ISO 6127:1981 specifies an analytical method for determining the phosphorus content in chromium ores using the reduced molybdophosphate photometric method. Developed by the International Organization for Standardization (ISO), this standard provides detailed procedures, safety instructions, and guidance on expressing analytical results. The method applies to chromium ore products with phosphorus content ranging from 0.002% to 0.1% (mass/mass). Designed for laboratories and industry professionals, ISO 6127 is an essential reference for ensuring accurate phosphorus quantification in chromium minerals.
Key Topics
- Scope: Targets the determination of phosphorus in chromium ores, with an applicable range of 0.002% to 0.1% phosphorus content.
- Analytical Principle: Employs photometric measurement of a reduced molybdophosphate complex, using a spectrophotometer or photoelectric absorptiometer.
- Sample Preparation: Includes decomposition of test portions by either acid treatment or alkaline fusion, removal of interfering substances (such as chromium and arsenic), and filtration steps.
- Reagents and Apparatus: Requires specific chemicals (e.g., nitric acid, perchloric acid, hydrofluoric acid, ammonium molybdate, iron(III) nitrate) and laboratory equipment, emphasizing strict safety due to hazardous reagents.
- Procedure: Details sample weighing, stepwise chemical treatments, formation and reduction of a molybdophosphate complex, and photometric measurement at specified wavelengths.
- Results Expression: Outlines calculation methods for phosphorus content and permissible tolerances for duplicate determinations.
- Safety: Includes explicit warnings regarding the use and handling of perchloric acid and hydrofluoric acid, stressing the necessity of fume hoods and personal protective equipment.
Applications
The ISO 6127:1981 standard is crucial for:
- Quality Control in Mining and Metallurgy: Enables reliable analysis of phosphorus levels in chromium ores, which is key for assessing ore quality and suitability for metallurgical processing.
- Laboratory Testing: Provides a validated procedure for chemical laboratories specializing in mineral analysis, ensuring consistent and internationally recognized results.
- Regulatory Compliance: Assists organizations in meeting industry and governmental requirements for ore composition, especially where phosphorus content impacts product performance or environmental compliance.
- Research and Development: Supports R&D in the mining sector for process optimization, material selection, and environmental monitoring.
Related Standards
ISO 6127 should be read in conjunction with other relevant standards for comprehensive analytical procedures:
- ISO 6629: Chromium ores and concentrates - Methods of chemical analysis - General instructions: A foundational reference that provides general laboratory practices and guidance for the chemical analysis of chromium-containing materials.
- Other Related ISO Standards:
- ISO 4791: General rules for inorganic chemical analysis in ores and minerals.
- ISO 10719: Determination of other trace elements in minerals.
- ISO 3657: Sampling and testing of ferroalloys.
Practical Value
- Accuracy: Ensures repeatable and precise determination of low-level phosphorus in industrial minerals.
- Global Acceptance: Recognized internationally, facilitating trade and quality assurance across borders.
- Safety Emphasis: Addresses operational risks, making laboratories aware of necessary precautions when handling hazardous chemicals.
By following ISO 6127:1981, mineral testing laboratories and industry professionals can standardize their phosphorus measurement processes, ensure accurate reporting, maintain regulatory compliance, and uphold high-quality standards in the chromium ore supply chain.
Open preview (PDF)Chromium ores — Determination of phosphorus content — Reduced molybdophosphate photometric method