Development of Karl Fischer Reagents

I-1. Questions & Answers about Karl Fischer Reagents
[Procedures]
a) After carefully drying the dropper bottle, introduce the sample. Attach the
pipette and extract the sample.
b) Accurately weigh all the equipment.
c) Remove the pipette from the dropper bottle and titrate the titration solvent.
d) Replace the pipette on the dropper bottle and weigh the equipment
accurately.
e) The difference between the two weights is the weight of the sample.
(5) Dropper bottle (for high-viscosity substances)
This equipment (Figure 10) is used for samples with the viscosity of treacle.
Procedures are the same as in (4) above.
2. Solid Samples
The appropriate method must be selected with reference to the varying
characteristics and forms of solid samples. There are commercial products
that are suitable for each method and it is convenient to use these.
As the sample insertion aperture on the titration flask must be opened to
insert the sample, a blank test must be carried out to adjust for the time
while the flask is open. In general, the following procedures are used.
a) Obtain the required amount of sample using a thoroughly dried sampling
bottle.
b) Accurately weigh the sampling bottle.
c) Remove the stopper of the sample insertion aperture on the titration flask
and quickly insert the sample.
d) Close the stopper and record the time that stopper was open. (The lid
should be opened for exactly the same period of time during the blank
test.)
e) Weigh the sampling bottle.
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Figure 9: Dropper bottle
Figure 10: Dropper bottle
(for high-viscosity substances)