Development of Karl Fischer Reagents

Substance
LPG
Ethylene
Propane
Butadiene
Flon gas R113
Spray cans
5. Coals, Tars
Key Points
Sample quantity
(g)
23.24
40.06 L
6.50
16.63
7.97
6.26
Titration quantity
(µg)
253
55
280
120
234
1008
Chapter III: Applications - 2
Moisture content
(ppm)
11
1.7
43
7.2
29
161
The moisture content of coals is normally measured using a moisture
vaporization system. Measurements can be obtained using either
volumetric or coulometric titration.
Tars are subjected to Karl Fischer titration using the moisture
vaporization system designed for oils.
[Examples of Measurement]
(1) Volumetric titration
Reagents used: Karl Fischer Reagent SS-Z (or SS)
Dehydrated Solvent GEX, OL II (or MS, CM) 25-50ml
Substance
Brown coal
Coal tar
Dehydrated
solvents
General-use
Oil-type
Sample Quantity
(g)
0.0389
0.1619
Measurement Value
(mg)
4.38
7.30
Moisture Content
(%)
11.3
04.5
(2) Moisture vaporization - Volumetric titration
Reagents used: Karl Fischer Reagent SS-X (or SS)
Dehydrated Solvent GEX (or MS) + PG (3:1) 50-100ml
Substance
Heating Temperature
( � C)
Sample Quantity
(g)
Measurement Value
(mg)
Moisture Content
(%)
Powdered coal 150 0.1262 5.76 4.56
141