Hach DR2400 - Page 343

DR/2400
Iron, Total
IronTot_AVPP_Other_TPT_Eng_Ody.fm Page 1 of 6
• Digestion is required for determining total iron. See the Hach Water Analysis Handbook for digestion procedures.
• For more accurate results, determine a reagent blank value for each new lot of reagent. Follow the procedure using deionized
water in place of the sample. Subtract the reagent blank value from the final results or perform a reagent blank adjust
. See the
instrument manual for more information on Running a Reagent Blank.
• Rinse all glassware with a 1:1 Hydrochloric Acid Solution (Cat. No. 884-49). Rinse again with deionized water. This process will
remove iron deposits that can cause slightly high results.
• Wipe all blanks, sample cells, and ampules with a damp cloth followed by a dry cloth to reduce fingerprints and other marks
before placing in the instrument.
• After adding reagent, a blue color will develop if iron is present.
• Adjust the pH of stored samples to 3–4. Do not exceed pH 5 or iron may precipitate.
Iron, Total
Method 8112
TPTZ Method*
* Adapted from G. Frederic Smith Chemical Co., The Iron Reagents, 3rd ed. (1980)
Powder Pillows or AccuVac
®
Ampuls
(0.012 to 1.800 mg/L)
Scope and Application: For water, wastewater, and seawater
1. Touch
Hach Programs.
Select program
270 Iron, Total TPTZ.
Touch
Start.
2. Fill one clean, round
sample cell with 10 mL of
sample (this is the
prepared sample).
Fill another cell with
10 mL of deionized water
(this is the blank).
3. Add the contents of
one 10-mL TPTZ Iron
Reagent Powder Pillow
to the prepared sample.
Stopper and shake for
30 seconds. Remove cap.
4. Touch the timer icon.
Touch
OK.
A three-minute reaction
period will begin.
Proceed to step 5 while the
timer is running.
Tips and Techniques
TPTZ Powder Pillows Method 8112
Hach Programs