Hach DR/850, Руководство по процедурам, Страница: 71 / 460

71
Method 8012
ALUMINUM
(0 to 0.80 mg/L) For water and wastewater
Aluminon Method
*
1.
Enter the stored
program number for
aluminum (Al).
Press:
PRGM
The display will show:
PRGM ?
Note: Adjust the pH of
stored samples before
analysis.
Note: For most accurate
results, perform a Reagent
Blank Correction using
deionized water (see
Section 1).
2.
Press:
1 ENTER
The display will show
mg/L, Al and the
ZERO icon .
Note: Total aluminum
determination requires a
digestion prior to analysis
(see Section 2).
Note: For alternate form
(Al
2
O
3
), press CONC .
3.
Fill a 50-mL
graduated mixing
cylinder to the 50-mL
mark with sample.
Note: Rinse cylinder with
1:1 Hydrochloric Acid and
deionized water before use
to avoid errors due to
contaminants absorbed on
the glass.
Note: Sample temperature
must be 20-25 °C (68-77 °F)
for accurate results.
4.
Add the contents of
one Ascorbic Acid
Powder Pillow. Stopper.
Invert several times to
dissolve powder.
5.
Add the contents of
one AluVer
®
3
Aluminum Reagent
Powder Pillow. Stopper.
Note: A red-orange color
develops if aluminum
is present.
Note: Inconsistent results
will occur if any powder
is undissolved.
6.
Press:
TIMER ENTER
A three-minute reaction
period will begin. Invert
the cylinder repeatedly
for the three minutes.
7.
Pour 25 mL of
mixture into a 25-mL
sample cell (the
prepared sample).
8.
Add the contents of
one Bleaching 3 Reagent
Powder Pillow to the
remaining 25 mL in the
mixing graduated
cylinder (the blank).
Stopper the cylinder.
* Adapted from Standard Methods for the Examination of Water and Wastewater