Boiling points of the products.
Diethylamine - 55.5 C.
Water - 100 C.
Sodium Formate > 100 C. (decomposes at high temperature)
Set up glassware for distillation using a 2-neck flask. Make a satured solution of sodium hydroxide and place in a pressure equalised addition funnel and stopper the top of the top of the funnel. Put the funnel in 1 neck. Then, from the other neck, add a still head and condenser with COLD (to get the vapour below 55.5 C) water and collection funnel. Now you add the NaOH solution at a rate which stops excessive heating (some DEA will come over right away). For every mole of NaOH added, a mole of DEA is produced. Once the addition is complete, allow everything to cool and replace the addition funnel with a thermometer (in quickfit adaptor) and heat the solution until the temperature is about 60-65 C. The DEA will distill over. You will know when the DEA has all boiled off as the temperature will rise. Stop at that point. In the reciever flask you have almost 100% pure DEA. It can have traces of water removed through re-distillation or by adding a drying agent such as sodium sulfate and shaking and then leaving the liquid to stand. DEA smells BAD and should be kept in a sealed container in a refridgerator. Make sure you read the MSDS of all the compounds but it's easy as that.
