Hach DR/850, Procedures Manual, Page: 299 / 460

299
Method 10173
ORGANIC CARBON, TOTAL, Mid Range
(15–150 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 Mid
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 1.0 mL of
organic-free water to
the reagent blank vial
and1.0 mL of prepared
sample to the sample
vial. Do not cap the vial;
swirl gently 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