ISO 21587-1:2007

Overview

ISO 21587-1:2007 specifies the apparatus, reagents, dissolution procedures and gravimetric silica determination used for the chemical analysis of aluminosilicate refractory products and raw materials. Published as Part 1 of the ISO 21587 series, it provides a validated wet-chemical alternative to X-ray fluorescence (XRF) (ISO 12677:2003) for laboratories that perform classical chemical analysis. The standard defines preparation and standardization of solutions, fusion/dissolution techniques and the gravimetric determination of SiO2.

Key topics

• Scope and purpose
  • Alternatives to the XRF fused bead method for aluminosilicate refractories.
  • Use in conjunction with ISO 21587-2 (wet chemical analysis) and ISO 21587-3 (ICP/AAS methods).
• Apparatus and materials
  • Use of platinum crucibles, beakers, volumetric flasks and desiccators for high-temperature fusion and solution preparation.
• Reagents and standard solutions
  • Detailed recipes and standardization methods for volumetric solutions (e.g., CyDTA, EDTA, zinc solutions).
  • Preparation of 1 mg/ml and dilute standard solutions for major oxides: SiO2, Al2O3, Fe2O3, TiO2, CaO, MgO, Na2O, K2O, Cr2O3, ZrO2, P2O5, MnO, etc.
• Dissolution and fusion techniques
  • Sodium carbonate fusion for silica, acid digestion (including use of hydrofluoric and sulfuric acids) for refractory oxides, and procedures for preheating and ignition where required.
• Gravimetric silica
  • Procedures for gravimetric determination of silicon(IV) oxide (SiO2) as a primary measurement approach in the absence of XRF.

Applications

• Quality control and acceptance testing of aluminosilicate refractories in manufacturing and raw material supply chains.
• Analytical laboratories requiring a certified wet-chemical procedure for reporting oxide compositions when XRF is unavailable or unsuitable.
• Research and development for ceramics, refractories and high-temperature materials where precise oxide determinations (including gravimetric SiO2) are needed.
• Regulatory compliance and certification that mandates traceable, standardized chemical analysis methods.

Who uses this standard

• Refractory manufacturers and QC laboratories
• Materials scientists, ceramic engineers and metallurgists
• Third‑party testing labs and accreditation bodies
• Laboratories transitioning between XRF and wet-chemical or ICP/AAS techniques

Related standards

• ISO 21587-2 - Part 2: Wet chemical analysis
• ISO 21587-3 - Part 3: Inductively coupled plasma and atomic absorption spectrometry methods
• ISO 12677 - XRF fused bead method (alternative referenced)
• ISO 26845 - General requirements for wet chemical, AAS and ICP methods

Keywords: ISO 21587-1, chemical analysis, aluminosilicate refractory products, gravimetric silica, wet chemical analysis, XRF alternative, reagents, dissolution, standard solutions, refractory quality control.