1.6. Use of the DOSER during reflux or under controlled atmosphere

Vapours of boiling solvents can penetrate into the lower part of the DOSER and condense. The condensation disturbs the flow of the solid. This can be prevented by blowing a light stream of air or another convenient gas through the DOSER vessel. The vapours are displaced and cannot disturb the dosing.

The gas is introduced by a special stopper fitted with tubing. For this purpose we deliver a polyethylene stopper. However, any fitting compatible with NS 29/32 ground fittings (e.g. SVL threaded fittings which can be adapted to several tubing diameters are excellent). The slight gas stream passes through the hollow axis of the distributor and the lower part of the DOSER vessel. The stream and pressure of the gas must be carefully controlled to prevent compression of the solid substance during the dosing process.

Since the DOSER is airtight, it can also be used for work under controlled atmosphere (nitrogen, argon etc). The DOSER withstands a pressure of ± 0.05 MPa. The airtight DOSER is particularly useful during work with oxygen sensitive or hygroscopic substances. In this case manual dosing is very difficult.