IKA AOD 1 - Manual (Page 57)

6 Carrying out Decomposition Tests
IKA  -WERKE AOD 1 Ver. 01 01.03
Page 6-4
Solution in decomposition vessel
Ten ml of 0.25 molar NaOH solution and 100 to 200 µl of 30 % hydrogen peroxide
solution are standard additions to the decomposition vessel. Other additions and
concentrations are also possible, depending on the anticipated composition of the
sample (see also instructions for using AOD 1.11 and AOD 1.12).
Securing a sample in the holder
Then a crucible with the weighed sample is placed in the crucible holder, and se-
cured with the retaining ring. Place the retaining ring below the crucible holder
around the crucible. The crucible is then held to the holder, and cannot come loose,
even when the vessel is shaken.
If a combustible crucible is used, the retaining ring is not required.
Closing the decomposition vessel
Close the decomposition vessel by placing the lid with the sample in it until there is
metallic contact. Screw the ring nut on to the decomposition vessel until it is just
tight. The decomposition vessel is now ready for filling with oxygen.
➃
Filling the decomposition vessel using Oxygen Filling Station C 48
Fill the decomposition vessel with oxygen using the Oxygen Filling Station C 48.
Please read the C 48 operating instructions.
The oxygen pressure should be at least 30 bar, but must not exceed 40 bar.
Quality 3.5 oxygen (99.95 % pure) should be used.
Hold the hand lever of the Oxygen Filling Station firmly while moving it; the
pressure in the decomposition vessel can cause the lever to move rapidly up-
wards (danger of shock)
☞
1
2
3
1 Hand lever
2 Filling head
3 Support
Oxygen Filling
Station C 48