EN ISO 21068-2:2008

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Determination of change in mass
   4.1 General
   4.2 Determination of the loss on drying at 250 degrees C
        (LOD[250]) gravimetric method
   4.3 Determination of the loss on calcination in argon
        (LOI[Ar])
   4.4 Determination of the change in mass by heat
        pretreatment in air
   4.5 Determination of the change in mass at 750 degrees C
        (LOI[750])
   4.6 Determination of loss on ignition at 850 degrees C
        (LOI[850])
   4.7 Determination of loss on ignition at 1050 degrees C
        (LOI[1050])
5 Determination of the total carbon content
   5.1 General
   5.2 Combustion techniques
   5.3 Detection techniques
   5.4 Detection methods
6 Determination of free carbon content
   6.1 General
   6.2 Sample decomposition by combustion
   6.3 Detection techniques
   6.4 Direct detection methods
   6.5 Indirect detection methods
   6.6 Direct determination of free carbon by wet oxidation
7 Determination of silicon carbide content, SiC
   7.1 General
   7.2 Determination of silicon carbide, SiC, by indirect
        quantitative method
   7.3 Determination of silicon carbide, SiC, by direct
        quantitative method
   7.4 Determination of silicon carbide SiC by ignition method
        at 750 degrees C
   7.5 Determination of silicon carbide, SiC, by chemical
        method
8 Determination of total silicon content via silica
   8.1 Principle
   8.2 Reagents
   8.3 Apparatus
   8.4 Procedure
   8.5 Blank test
   8.6 Calculation
9 Determination of free silicon content
   9.1 Principle
   9.2 Pretreatment with hydrochloric acid
   9.3 Silicon determination by hydrogen evolution
   9.4 Silicon determination by silver displacement
10 Determination of silica content, SiO[2]
   10.1 General
   10.2 Determination of free and/or combined silica
        content, SiO[2]
   10.3 Determination of free silica, SiO[2]
   10.4 Determination of surface silicon dioxide, SiO[2]
11 Expression of results
12 Test report
Annex A (informative) Examples of CRMs for calibration
        of carbon analyser
Bibliography

ISO 21068-2:2008 specifies analytical techniques for the determination of change in mass by thermal treatment at specified temperatures, and methods for the determination of the total carbon content, free carbon, silicon carbide, silicon, total silica and free silica content of silicon-carbide-containing raw materials and refractory products.