How to use a rotary film evaporator

Check that the apparatus is ready for use by ensuring that  

Fill the rotating flask half-full or less, using a stemmed filter funnel. You must not contaminate the joint of the rotating flask with solute, which will be deposited there during evaporation, since you may not be able to remove the flask after evaporation. If the flask is too full it may bump , sending solution up into the condenser and receiver. You will then have to dismantle and clean out the equipment with an appropriate solvent to recover your cornpound. 

Attach the flask to the barrel and put plastic joint clips on all the joints, while supporting the flask with your hand. If the weight of the flask and contents springs any of the joints, k is too heavy replace it with a smaller flask or remove some of the solution. You must not rely on the power of the vacuum to hold your flask in place. 

Turn on the motor, slowly increasing the speed to the maximum. 

Close the vacuum inlet adapter slowly until it is fully shut and observe the flask for a few seconds, if boiling occurs (liquid is condensed to the receiver flask) continue until boiling stops and then lower the flask so that it just touches the surface of the water, lock it in place and boiling should recommence. As the volume of solution decreases, you may need to lower the flask further into the water bath until all the solvent has been evaporated. If a white coating of frost forms on the flask evaporation may stop, because the flask is too cold lower the flask into the water bath to warm it and evaporation should begin again. 

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