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Section 8 - How to obtain the best results
With readily volatile samples, rapid application of the sample on the sample pan is advisable, otherwise, moisture
can escape before the initial weight is recorded; here, use of the manual operating mode is appropriate.
Treating the sample during drying
Occasionally, following recording of the initial weight of the sample and before the actual drying, the test substance is
subjected to further treatment. The halogen Moisture Analyzer from OHAUS offers this possibility in the manual
operating mode.
Such applications could include:
Mixing of quartz sand: moisture which vaporizes during the mixing of the sample is correctly taken into account
in the final result.
Coagulation of protein by dropwise addition of alcoholic solutions. This prevents skin formation during drying.
Added solvent is not recorded in the final result.
Formation of readily volatile azeotropes by addition of solvents insoluble in water (e.g. xylene, toluene).
Note that the addition of solvents can lead to the formation of flammable or even explosive mixtures. With applica-
tions of this type, you should thus work with extremely small amounts of samples and with the necessary care. In
cases of doubt, a careful risk analysis must be performed.
Selection of the optimum sample weight
The sample weight has an influence on both the accuracy of the measurement results and the measurement time.
With large amounts of samples, a great deal of water must vaporize and the moisture determination takes longer.
To keep the measurement time as short as possible, we advise you choose a low weight for your sample, but not so
low that attainment of the required measurement accuracy is no longer possible.
Correct sample distribution
Incorrect sample distribution
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