Application notes
IMPORTANT NOTE: THE PROCEDURES DESCRIBED
IN HERE, APPLY ONLY TO THE CATALYTIC ACTIVATED AND HALOGEN
RESISTANT DECOMPOSITION VESSEL C 5012. THEY CAN NOT BE USED
WITH THE C 5010 DECOMPOSITION VESSEL!
If you needs to analyze Halogens and/or sulfur after the
decomposition, a variety of different methods to do so are
shown below.
The examples described below are done with the IKA –
Control standards AOD 1.11 and AOD 1.12. These control standards
are mineral oils that contain a known amount of Chlorine,
Sulfur and Fluorine, Bromine.
To get the best results on Halogens and Sulfur it is required
to use the special decomposition vessel C5012 or the AOD
1 Decomposition System. The C 5012 decomposition vessel
can be used with the C 2000 or C 5000 Calorimeter. We also
offer them in Packages “C 2000 basic Version 2 (Package)”
and “C 5000 Package 1/12”. This vessel can not
be used with the C 200 Calorimeter!
Sample preparation
From the homogeneous
standard oil AOD 1.11 0.2 - 0.5 g of the sample are filled
directly into the quartz crucible and/or into the C 10 Acetobutyrate
Capsule.
The originally
weighted-in quantity of the sample material is noted or
entered into the Calorimeter. It is required later again
for the content calculation. If using the capsules the weight
of the empty capsule has to be noted as well, or entered
into the Calorimeter, since the energy additionally introduced
thereby must be deducted from the gross calorific value
as foreign (aka spike) energy that is not created by the
sample itself. We do have special automated solutions for
this procedure in combination with a balance connected to
the Calorimeter. Please contact us for further details.
Preparing
the decomposition vessel
5-10 ml of the
absorption solution is filled into the decomposition vessel.
The absorption
solution can vary in composition and concentration depending
on the specifications of the sample and the method used
to analyze the Halogens and/or Sulfur.
The most common
used absorption solution is composed of:
10 ml of 0.25 Sodium hydroxide (NaOH) and
200?l of 30% Hydrogen peroxide (H2O2)
This standard
absorption solution is suitable for almost all applications.
If a different solution is used in any of the following
application, it is mentioned separately
In some cases
it is necessary to use the “C 5030 Venting station”.
Especially when looking at Iodine (I) or traces respectively
high quantities of Halogens. In this case the washing-bottle
of the station is filled with the appropriate amount of
absorption solution as well.
A cotton thread
is connected to the ignition wire and the quartz crucible
(with the weighed in sample) is inserted into the crucible
holder of the decomposition vessel. The cotton thread is
hung into the crucible that it will ignite the Acetobutyrate
Capsule or oil when the ignition is done by the Calorimeter.
The decomposition
vessel is closed and hung into the Calorimeter’s decomposition
vessel acceptance.
The Calorimeter
is started and fills oxygen into the vessel. In some cases
it is necessary to fill and vent the decomposition vessel
several times before starting the actual measurement. This
procedure varies depending on the Calorimeter that is used.
Please contact IKA for further details.
ION-CHROMATOGRAPHY
- Sulfur (S) & Halogens (F, Cl, Br, I)
The determination
was done with an Ion chromatograph manufactured by Dionex
(DX- 1000/120) by means of a conductivity measurement.
This procedure
allows the determination of all Halogens and Sulfur in one
run! It is probably the most convenient, but also most expensive
solution.
The absorption
solution is specially created around the Eluent used with
the IC, in order to get rid of the “water-peak”,
and to optimize the performance of the IC.
1 Liter of the
absorption solution consist of: 1 Liter stock solution consists
of:
50 ml stock solution
21.2 g Na2CO and 6.30 g NaHCO3
25 ml 30% H202
7 - 8 NaOH – pellets
Follow the steps
described in the section “Rinsing the decomposition
vessel”.
A sample is taken
and injected into the IC that will show all Halogens and
Sulfur on one chromatogram only
TITRATION
- Chlorine (Cl)
The
determination of Chlorine was done with a Titration processor
by titrating against with silver nitrate (AgNO3).
Follow the steps described in the section “Rinsing
the decomposition vessel”.
An aliquot is
removed for the measurement (50.0 ml or 100.0 ml) and transferred
into a titration cup.
The aliquot factor
is noted and needed later for the calculation of the result.
The titration cup is then filled approximately halfway with
distilled water and 2 ml of concentrated Nitric acid (HNO3)
are added.
The titration
cup is then placed into the analysis processor and the corresponding
procedure is started. After several minutes the result is
shown on the display in milligrams. The halogen concentration
can be calculated from this taking the originally weighted-in
quantity and the aliquot factor into consideration
ION
SELECTIVE ELECTRODES (ISE) - Chlorine (Cl)
The determination of Chlorine (Cl) was done with a Potentiometer,
equipped with a Solid-Ion-selective-Electrode Cl 500 in
combination with the Reference-electrode R 502.
Follow the steps described in the section “Rinsing
the decomposition vessel”.
Experience from these measurements as well with other samples
showed that this method is not suitable for all applications.
If the sample contains other Halogens than just Chlorine
(Cl), Bromine (Br) can interfere with the Chlorine (Cl)
electrode for example.
PHOTOMETRY
- Sulfur (S)
Sulfur can be found in the absorption solution in the form
of Sulfate (SO42-). The determination of Sulfate (SO42-)
was done with a Photometer.
Follow the steps described in the section “Rinsing
the decomposition vessel”.
The error of this test is probably a little too high for
some customer requirements. But might still be good enough
for „quick-test“ applications.
ION-CHROMATOGRAPHY
- Iodine (I)
The sample analyzed in this application was a mineral fodder
for cows. Similar tests have been done with birdseeds as
well.
The determination of Iodine (I) was done with an Ion-chromatograph
with a UV/VIS-Detection unit.
NOTE: For this application the C 5030 Venting station is
absolutely required to get good results. 50 ml of the absorption
solution described above are filled into the washing bottle.
Follow the steps described in the section “Rinsing
the decomposition vessel”.
There are two important things to mention for this application.
The vessel needs to be shaken before venting it very slowly
(for 90 minutes) through the absorption solution in washing
bottle of the C 5030 venting station.
AAS
- Mercury (Hg) & Arsenic (As)
IKA has a lot more applications and experience than what
is shown here.
Please contact us directly for further detailed information
and more details on the applications shown above.
Rinsing
the decomposition vessel
After the experiment
is done, the Calorimeter opens up. Remove the decomposition
vessel, vent the gases under a fume hood, or connect it
to the “C5030 Venting station”. The gases need
to be vented slowly through the absorption solution inside
the washing bottle of the venting station.
Rinse the vessel
carefully with distilled water or if using an Ion-chromatograph,
use the Eluent. Care should be taken to ensure that all
parts of the vessel are rinsed.
Rule of thumb:
better rinse 2-3 times with small quantities of distilled
water or Eluent than only once with a lot of distilled water
or Eluent!
The absorption
solution in the decomposition vessel, as well as the absorption
solution in the washing-bottle of the “C 5030 Venting
station” are filled from the washing bottle into a
volumetric flask with the appropriate volume, and is filled
up to its calibration mark.
Cleaning
the decomposition vessel C 5012
IMPORTANT
NOTE: THE PROCEDURES DESCRIBED IN HERE, APPLY ONLY
TO THE CATALYTIC ACTIVATED AND HALOGEN RESISTANT DECOMPOSITION
VESSEL C 5012. THEY CAN NOT BE USED WITH THE C 5010 DECOMPOSITION
VESSEL!
It must be guaranteed
that no contamination is present in the decomposition vessel,
and it needs to be cleaned in a way that the elements to
be determined are not present in the cleaning agent. For
example, do not use Hydrochloric acid (HCl) to clean the
vessel if Chlorine has to be determined!
Suitable cleaning
agents are acetone, isopropyl alcohol and distilled water.
In cases of trace analysis the decomposition vessel can
be cleaned with concentrated nitric acid (HNO3). Contact
IKA for more details on this procedure before performing
it!
The decomposition
vessel is then dried using a lint-free cellulose cloth or
the like, and can be prepared for the decomposition.
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