Iron LR L (A) / M225
Chemical Method
Ferrozine / Thioglycolate
Appendix
Interferences
EN
Removeable Interferences
1. If using KS61 (Ferrozine/Thioglycolate), a high concentration of molybdate will result
in an intense yellow colour. In this instance, a chemical blank value is required:
Use two clean 24 mm vials.
•
•
Mark one as blank for zeroing.
•
Fill a clean vial (24 mm) with 10 ml of the sample (blank).
•
Add 10 drops of KS63 (Thioglycolate) to the vial.
•
Close the vial with the cap and swirl the contents to mix them.
•
Place the blank in the sample chamber.
•
Pay attention to the positioning.
•
Press the ZERO button.
•
Remove the vial from the sample chamber.
•
Fill a second clean vial (24 mm) with 10 ml of the sample (this is the sample vial).
•
Add 10 drops of KS63 (Ferrozine/Thioglycolate) and as before, follow the
procedure as described.
Interference
Co
Cu
Oxalat
CN
-
NO
-
2
Bibliography
D. F. Boltz and J. A. Howell, eds., Colorimetric Determination of Nonmetals, 2nd ed., Vol.
8, p. 304 (1978). Carpenter, J.F. "A New Field Method for Determining the Levels of Iron
Contamination in Oilfield Completion Brine", SPE International Symposium (2004)
56
from / [mg/l]
8
2
500
10
EN Method Reference Book 1.0