Hach DR2400 - Page 350

Iron, Total
Iron, Total
Page 2 of 4
IronTot_PP_Other_FMO_Eng_Ody.fm
Interferences
5. Fill a clean, round
sample cell to the 25-mL
mark with prepared
sample. Save the
remaining 25 mL of
prepared sample for
step 8.
6. Add the contents of
one FerroMo Iron
Reagent 2 Powder Pillow
to the sample cell. Swirl
to dissolve the reagents.
This is the developed
sample. A blue color will
develop if iron is present.
A small amount of
undissolved reagent will
not affect the results.
7. Touch the timer icon.
Touch
OK.
A three-minute reaction
period will begin.
8. Fill a second round
sample cell with the
remaining 25 mL of
prepared sample from
step 5 (the blank).
9. When the timer
beeps, insert the blank
into the cell holder.
10. Touch Zero.
The display will show:
0.00 mg/L Fe
11. Place the developed
sample into the cell
holder.
12. Touch Read.
Results will appear in
mg/L Fe.
Interfering Substance Interference Levels and Treatments
pH
A sample pH of less than 3 or greater than 4 after the addition of reagent may inhibit color
formation, cause the developed color to fade quickly, or result in turbidity. Adjust the sample pH
in the graduated cylinder before the addition of reagent to between 3 and 8 by using a pH meter
or pH paper and adding, dropwise, an appropriate amount of iron-free acid or base such as
1.0 N Sulfuric Acid Standard Solution (Cat. No. 1270-32) or 1.0 N Sodium Hydroxide Standard
Solution (Cat. No. 1045-32). Make a volume correction if significant volumes of acid or base are
used; see Section 3.1.3 Correcting for Volume Additions on page 29.
10 mL
20 mL
25 mL
10 mL
20 mL
25 mL
10 mL
20 mL
25 mL
10 mL
20 mL
25 mL
Zero
10 mL
20 mL
25 mL
Read