Voith BTG Mutek PCD-06, Руководство по эксплуатации

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© BTG 2021 Operation Manual Mütek
TM
PCD-06 25
IV. Installation
Conductivity
The conductivity of a sample decisively impacts the
streaming potential: the higher the conductivity, the
lower the electrical resistance in the sample will be and
the more the streaming potential will decrease without,
however, influencing the titration results.
Fig. 4-1 Conductivity vs. streaming potential
In Fig. 4-1, various different NaCl proportions were
added to anionic titrant 0.001 N and the samples were
titrated with cationic titrant 0.001 N.
Hint
If conductivities are excessively high (20 mS/cm - 50
mS/cm), the streaming potential may fluctuate between
anionic and cationic so than an endpoint detection and
thus titration is no longer possible. In these cases,
reduce the conductivity by diluting the sample with de-
ionized water.
Information
Samples that do not meet the above specifications may
be prepared as outlined in chapter 5.4 "Sample prepa-
ration", page 31.
4.5 Solutions
4.5.1 Titrants
Titrants must always carry the opposite charge of the
sample.
The sample concentration (dilution) should optimally be
selected to keep the titrant consumption between 0.2
and 10 ml.
Polyelectrolytes
BTG Instruments AB recommends the use of BTGs
anionic and cationic titrant as standard reagents, since
their charge densities are practically pH-independent.
Anionic and cationic titrant are available in 250 ml or
1000 ml volume for ready to use. As well it can be
ordered as concentrate to be prepared on site.
Hint
MSDS for concentrates are available on:
www.btg.com under MyBTG.