In this video we purify and dry highly contaminated diethyl ether using potassium hydroxide and sodium metal.
To a 500mL portion of dethyl ether we add 30g of potassium hydroxide and stir over night. The diethyl ether is then decanted off the aqueous layer of dissolved contaminants. Now 10g of sodium metal are added to the diethyl ether and the mixture stirred while loosely stopped to allow hydrogen escape. After all visible hydrogen evolution ceases (usually about one day) the flask is tightly stopped and allowed to stir vigorously until the sodium metal begins cold welding together into larger and larger aggregates. Alternatively, for professional labs, 0.2g of benzophenone maybe added before sealing and the color change to red or purple is indicated. This takes a couple of days but can take a week.