We have a new method for the determination of water in various materials.

It is based on the Dean and Stark method and uses a mixture of Toluene and mixture of Xylenes to carry the water over into a graduated receiver vessel where the water appears as a layer below the lighter solvent.

Hint: hover over the following images for zoom in and move around.

Recovery testing using known % of water.

The sample (last image) shows the collected water as lower phase after about 3 hours of distillation.  In this case, a very small drop of methylene blue was added to the receiver afterwards to aid the visualisation.

The technique is quite tricky to get right and requires some practise.  In order to get a good recovery a long wire can be inserted from the top of the condenser and by twisting the wire against the droplets the water they are encouraged to coalesce and drop to the bottom of the receiver to join the rest of the water.  This is illustrated by the tiny remaining traces of blue still on the sides of the receiver in this case.