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Section 8 - How to obtain the best results
The following procedure is suggested for selecting the temperature.
Estimate moisture content of the sample.
Determine the decomposition temperature of the sample by experiments.
Compare the measurement results with the reference method if one exists.
If an excessive amount of moisture is evolved, lower the drying temperature. If the experimental results are too
low, the drying temperature was possibly too low or the drying time too short.
With samples which have a high moisture
content, it is possible to shorten the measure-
ment time by selection of the step or rapid drying
program. Here, the greatest part of the existing
moisture is separated at an elevated temperature.
The drying temperature is then lowered and kept
constant until the end of drying. The excessive
temperature is used for rapid vaporization of the
moisture, but the effective sample temperature
does not exceed the boiling temperature of the
liquid (cooling effect through endothermic vaporization). In certain cases, local heating and decomposition could still
occur at the sample surface.
8.4 Selection of the drying program
Various drying programs are available in the Halogen Moisture Analyzer. There are four programs which control the
temperature profile. They are:
Standard drying program
Fast drying program
Ramp drying program
Step drying program
Standard drying
Standard drying is suitable for precise
determination of the moisture content of most
substances. For special cases or for time
optimized measurements, the selection of a
more complex drying program may be
advantageous.
Standard
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