Apply the sample to the sample pan:
t Apply the sample to the sample pan in a thin, even layer (height: 2 to 5 mm,
weight: 5 to15 g); otherwise:
– A sample applied unevenly will result in a nonuniform distribution of heat
– A sample will not be dried completely
– The analysis time will be unnecessarily extended
– The sample will burn or a crust/skin will form on its surface as a result of a
very thick layer
– The crust makes it difficult or impossible for moisture to escape from the
sample during the drying process
– An uncertain and unknown quantity of moisture will remain in the sample
t
Apply liquid samples, pasty samples, transparent samples, or samples that can
melt to a glass-fiber filter (order no. 6906940); this provides the following
benefits:
– Uniform distribution due to the capillary effect
– Liquids are prevented from beading together and forming drops
– With larger surfaces, the moisture can evaporate faster
– Colorless/transparent samples do not reflect
– Considerably more convenient than the “sea-sand method”
When drying samples containing sugar, a crust or skin can form and seal the
surface. A glass-fiber filter is particularly useful in such cases. The moisture can
evaporate downwards through the surface of the filter. Crust/skin formation can be
prevented or limited by placing the glass-fiber filter on top of the sample.
t Cover solid, heat-sensitive samples with a glass-fiber filter (order no. 6906940);
this provides the following benefits:
– Gentle heating, because the sample surface is shielded from excessive heat
– Higher temperature setting can be selected
– Uniformity of the sample surface
– Fast evaporation of the moisture
– Excellent repeatability for samples containing fat
Heating Programs
Two heating programs are available for performing moisture analysis of a
substance:
– Standard drying
– Gentle drying
Standard drying:
For standard drying, you need to enter the final temperature. The final temperature
is reached using an overshoot if necessary. The maximum set temperature is 160°C.
t [s]
T [°C]
Standardtrocknung
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