Volumetric moisture content determination apparatus

Essential oil determination results should always be expressed on a moisture-free basis. Therefore, alongside essential oil determination, moisture content determination of the same plant material also should be carried out using a proper glass apparatus (Dean Stark type). The technique involves distillation of the sample with an immiscible solvent (e.g., xylene and toluene) presaturated with water. Water within the plant material is codistilled with the volatile solvent and condensed into a graduated tube where water collects at the bottom of the tube below the solvent line. Solvent continuously returns to the distillation flask. The volumetric moisture content determination apparatus is shown in Fig. 9.2. 

FIGURE 9.2. Volumetric moisture content determination apparatus. 

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