Measurement
51
6.
Use the pH meter to check the pH value (pH 2 to pH 3) of each separating funnel (for
sample extraction and for zero point checking).
7.
Insert the stopper in each separating funnel (for sample extraction and for zero
point checking) and shake for approx. 5 minutes.
Tip
If the sample contains emulsifying substances, it is recommended that you shake for a shorter time
(approx. 1 minute).
Fig. 52 Extraction
Note
The internal pressure will increase as you shake. Open the cock from time to time to reduce the
internal pressure.
8.
After shaking, wait until the water and solvent get separated, and check the status
of the sample water. If almost no suspended material is visible and the water and
solvent have separated, collect the solvent layer (lower layer) and use that as the
measurement liquid. If there is suspended material or the water and solvent have
not sufficiently separated and the solvent layer is cloudy, proceed to the
"Removing suspended material" and "Removing water from the solvent layer"
procedures.
Removal of suspended material
1.
Filter the solvent layer through the filter paper into the glass container and use this
as the measurement liquid.
