Hach DR/850, Procedures Manual, Page: 307 / 460

307
Method 10128
ORGANIC CARBON, TOTAL, High Range
(20–700 mg/L C)
Direct Method
*
For wastewater and industrial waters
* Patent pending
1.
Turn on the
DRB 200 reactor. Heat
to 103-105 °C.
Note: See DRB 200 user
manual for selecting pre-
programmed temperature
applications.
2.
Use a graduated
cylinder to add 10 mL of
sample to a 50-mL
erlenmeyer flask
containing a stir bar.
3.
Add 0.4 mL of
Buffer Solution, pH 2.0.
Note: Use pH paper to make
sure the sample pH is 2.
4.
Place the flask on a
stir plate and stir at a
moderate speed for
10 minutes.
5.
Label two High
Range Acid Digestion
vials:
sample and
reagent blank .
Note: A reagent blank is
required for each series of
samples.
6.
Using a funnel, add
the contents of one TOC
Persulfate Powder
Pillow to each Acid
Digestion vial (colorless
liquid).
7.
Use a TenSette
®
Pipet to add 0.3 mL of
organic-free water to
the reagent blank vial
and 0.3 mL of prepared
sample to the sample
vial. Swirl to mix.
8.
Rinse two blue
Indicator Ampules with
deionized water and
wipe them with a soft,
lint-free wipe.
Note: Do not touch the
ampules on the sides after
wiping. Pick them up by the
top.
HRS MIN SEC HRS MIN SEC