KF Titer Determination with Water by Potentiometric Method

KF Titer Determination with Water by Potentiometric Method

Equipment
Potentiometer = 751 GPD Titrino / Titroprocessor
Electrodes = 6.0338.100 double Pt electrode; input Pol

Reagents
HYDRANAL® Composite 5; D0

Sample
20 -30 mL methanol, conditioned to complete dryness
10 μL dist. water

Remarks
Calculations:

Titer=C00/EP1*C01;4;mg/ml

Titer = titer of HYDRANAL® Composite 5
C01 = factor (1000 if water is used as standard; if methanol is used, enter its water content in mg/mL)

Answer

Titer = 0.010 / 1.9975 x 1000 = 5.0063 mg/mL

EP1 = 1.9975 mL
C00 = 1000

Common variables
C39 = MN1
Mean from 5 determinations.
Water or methanol standard can be injected either with a microliter syringe or with any syringe and reweighed.
Adjust the calculation value C01 according to your sample size: water
C00 in g C01=1000
C00 in mL C01=Density of H2O [mg/mL] 1
Methanol standard
C00 in mL C01=Content of methanol [mg/mL]
C00 in mL C01=0.001 * content of methanol [mg/mL]
For automatic curve output add in , >report “curve“.

Literature
Water determination by Karl Fisher titration, G. Wieland, GIT Verlag, Darmstadt (Germany)
HYDRANAL®, practical course, Water reagents according to Eugen
Scholz, Riedel de Haën, Seelze (Germany)
Metrohm Application Bulletin No. 77: KF water determination

Method documentation

'pa
751 GPD Titrino 15215 751.0010
KFT Ipol H2OTiter
parameters
>control parameters
EP at U 250 mV
dynamics 100 mV
max.rate max. ml/min
min.volume incr. min. ml
stop crit: drift
stop drift 20 ml/min
>titration parameters
titr.direction: -
pause 1 0 s
start V: OFF
pause 2 0 s
extr.time 0 s
dos.element: internal D0
I(pol) 50 mA
electrode test: OFF
temperature 25.0 °C
time interval 2 s
>stop conditions
stop V: abs.
stop V 99.99 ml
filling rate max. ml/min
>statistics
status: ON
mean n= 5
res.tab: original
>preselections
conditioning: ON
display drift: ON
drift corr: OFF
req.ident: OFF
req.smpl size: value
activate pulse: OFF
------------
'fm
751 GPD Titrino 15215 751.0010
KFT Ipol H2OTiter
>calculations
Titer=C00/EP1*C01;4;mg/ml

C00= 0.010
C01= 1000
------------
'fr
751 GPD Titrino 15215 751.0010
KFT Ipol H2OTiter
smpl size 0.010 g
EP1 1.9975 ml
Titer 5.0063 mg/ml
mean( 5) +/-s s/%
Titer 5.0058 0.00287 mg/ml 0.06
============
'cu
751 GPD Titrino 15215 751.0010
KFT IpolH2OTiter
10.0 s/div dV=0.5 ml/div
============
'st
751 GPD Titrino 15215 751.0010
statistics
## Titer
1 5.0050
2 5.0075
3 5.0013
4 5.0088
5 5.0063
mean( 5) +/-s s/%
Titer 5.0058 0.00287 mg/ml 0.06