41
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Sample
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D.I. Water
Sample
Sample
•
Choose a homogeneous sample. Samples containing settleable solids need to be homogenized with a
blender.
•
Preheat the Hanna Reactor HI 839800 to 150 °C (302 °F). For correct use of the reactor follow Reactor
Instruction Manual.
The optional HI 740217 safety shield is strongly recommended.
DO NOT USE AN OVEN OR MICROWAVE
samples may leak and generate a corrosive and possibly explosive
atmosphere.
• Remove the caps from two Reagent Vials.
• Add exactly 2.0 mL of sample to one vial (sample vial), and 2.0 mL of deionized water to the other
vial (blank vial), while keeping the vials at a 45-degree angle. Replace the cap tightly and mix by
inverting each vial a couple of times.
Warning
: The vials will become hot during mixing, be careful when handling them.
•
Insert the vials into the reactor and heat them for 2 hours at 150 °C.
•
At the end of the digestion period switch off the reactor. Wait for twenty
minutes to allow the vials to cool to about 120 °C.
• Invert each vial several times while still warm, then place them in the
test tube rack.
Warning
: The vials are still hot, be careful when handling them.
•
Leave the vials in the tube rack to cool to room temperature. Do not shake
or invert them, or else the samples may become turbid.
COD LR
Sample
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