BS 7020-22:1990

National foreword
Committees responsible
Method
1. Scope
2. Normative references
3. Principle
4. Reagents
5. Apparatus
6. Sampling and samples
7. Procedure
8. Expression of results
9. Test report
Annexes
A. Flowsheet of the procedure for the acceptance of
    analytical values for test samples
B. Derivation of repeatability and permissible
    tolerance equations
C. Precision data obtained by international analytical
    trial
Table
B.1 Acid-soluble iron (II) contents of the test samples
Figure
C.1 Least-squares fit of precision against X for acid-
    soluble iron (II)

Method for natural and processed iron ores containing from 1% to 25% acid-soluble iron (II) and only traces of metallic iron.

This International Standard specifies a method for the determination of iron(II) content in natural and processed iron ores containing from 1 % to 25 % acid-soluble iron(II) and only traces of metallic iron. This method is specifically limited for use in conjunction with the reducibility test methods specified in ISO 4695 or ISO 7215.

This method is not applicable to ores containing more than 0,3 % (m/m) sulfur (as sulfide) and/or 5 % (m/m) free carbon. Experiments have shown that the acid-insoluble residue can be neglected, especially as regards the needs of the reducibility test methods concerned and the precision obtainable.