Overview
EN ISO 20565-2:2008 (ISO 20565-2:2008) specifies wet chemical analysis methods for the quantitative chemical analysis of chrome-bearing refractory products and raw materials. Published by CEN/ISO in 2008 as the European adoption of the ISO text, this standard provides an alternative to X‑ray fluorescence (XRF) and covers classical “wet process” laboratory techniques for determining major and minor oxide constituents in refractory samples.
Key topics and technical requirements
- Scope and applicability
- Applicable to chrome-bearing refractories and raw materials within specified concentration ranges (examples from the standard):
- SiO2: 0.5–10% | Al2O3: 2–30% | Fe2O3: 0.5–25% | Cr2O3: 2–60% | MgO: 15–85%
- Other analytes: TiO2, MnO, CaO, MgO, Na2O, K2O, ZrO2, P2O5, and loss on ignition (LOI).
- Analytical methods included
- Wet-chemical colorimetric methods (e.g., molybdenum blue and coagulation/dehydration variants) for silicon(IV) oxide (SiO2).
- Classical titrations and colorimetric procedures for Al2O3, Fe2O3, TiO2, MnO, CaO, MgO.
- Flame photometry / spectrophotometry for sodium oxide (Na2O) and potassium oxide (K2O).
- Specialized absorptiometric and complexometric methods (e.g., xylenol orange for ZrO2).
- Procedures include requirements for calibration, blank tests, sample dissolution (referenced to Part 1), and test report content.
- Quality and procedural controls
- Use of calibrated standards and plotting of calibration graphs.
- Duplicate measurements and acceptance criteria for absorbance repeatability.
- Normative references and linkages to ISO 20565-1 (apparatus, reagents, dissolution) and ISO 26845 (general requirements).
Practical applications and users
- Who uses it
- Quality control laboratories in refractory manufacturing.
- Raw material suppliers and incoming inspection teams.
- Independent testing laboratories and research institutions assessing chrome-bearing bricks, magnesiaspinel, dolomite-chrome mixes, and similar refractory materials.
- Regulatory and certification bodies needing traceable, validated chemical results.
- Why use it
- Provides a validated alternative to XRF when elemental interference, instrument availability, or cross-validation is required.
- Suitable for samples where wet-digestion and classical chemistry offer improved specificity for certain oxides.
- Useful for routine QC, supplier qualification, failure analysis and compositional verification.
Related standards
- ISO 20565-1:2008 - Apparatus, reagents, dissolution and gravimetric SiO2 determination.
- ISO 20565-3:2008 - Flame AAS and ICP-AES methods (instrumental alternatives).
- ISO 26845:2008 - General requirements for wet chemical analysis, AAS, and ICP-AES.
Keywords: EN ISO 20565-2:2008, wet chemical analysis, chrome-bearing refractory, chemical analysis, refractory testing, molybdenum blue, flame photometry, SiO2, Cr2O3, refractories.