425
Method 8193
TANNIN AND LIGNIN (0 to 9.0 mg/L) For water, wastewater, boiler water
Tyrosine Method
*
1. Enter the stored
program number for
tannin and lignin.
Press:
PRGM
The display will show:
PRGM ?
2. Press: 98 ENTER
The display will show
mg/L, tanic and the
ZERO icon.
3. Fill a clean sample
cell to the 25-mL mark
with deionized water
(the blank).
4. Fill a clean sample
cell to the 25-mL mark
with sample (the
prepared sample).
Note: Filter turbid samples
and report results as mg/L
soluble tannic acid.
5. Pipet 0.5 mL of
TanniVer 3 Tannin-
Lignin Reagent into
each cell. Swirl to mix.
6. Pipet 5.0 mL of
Sodium Carbonate
Solution into each cell.
Swirl to mix.
Note: A blue color will
develop if tannins and/or
lignins are present.
7. Press:
TIMER ENTER
A 25-minute reaction
period will begin.
8. Place the blank in the
cell holder. Tightly
cover the sample cell
with the instrument cap.
* Adapted from Kloster, M.B., Journal American Water Works Association, Vol. 66, No. 1, p. 44 (1974).