Hach DR/850, Procedures Manual, Page: 341 / 460

341
Method 8007
PHOSPHONATES
(0-2.5 to 0-125 mg/L)
For water, wastewater, and seawater
Persulfate UV Oxidation Method
*
1.
Enter the stored
program number
for phosphonates.
Press:
PRGM
The display will show:
PRGM ?
Note: For most accurate
results, perform a Reagent
Blank Correction using
deionized water (see
Section 1).
2.
Press:
80 ENTER
The display will show
mg/L, PO4 and the
ZERO icon .
3.
Choose the
appropriate sample size
from
Table 1 below.
Pipet the chosen sample
volume into a 50-mL
graduated mixing
cylinder. Dilute the
sample to 50 mL with
deionized water.
Mix well.
Note: Clean glassware with
1:1 hydrochloric acid,
followed by a deionized
water rinse. Do not use
commercial detergents
containing phosphates to
clean glassware.
4.
Fill a sample cell to
the 10-mL mark with
diluted sample from
Step 3 (label this as
the blank).
Fill another sample cell
to the 25-mL mark with
diluted sample from
Step 3 (label this as
the sample).
Table 1
* Adapted from Blystone, P.; Larson, P., A Rapid Method for Analysis of Phosphonate Compounds , International
Water Conference, Pittsburgh, Pa. (Oct. 26-28, 1981).
Expected Range (mg/L phosphonate) Sample Volume (mL)
0-2.5 50
0-5 25
0-12.5 10
0-25 5
0-125 1