Preparation of Diethyl Sulfate
Ninety grams of sodium sulfate is placed in a dry 1 liter flask connected with a condenser and a receiver arranged for vacuum distillation. The flask is heated by means of an oil bath to 155-165°C. The apparatus is exhausted as nearly as possible by means of a filter pump, and misture of 50 grams of ethanol and 104.5 grams of concentrated sulfuric acid is allowed to drop through a capillary tube on the sodium sulfate at a rate of 120-150 drops per minute. The distillation of the mixture requires about one and one half hours for completion. The distillate, which consists of ethanol and diethyl sulfate is poured into a separatory funnel, the ethanol may be recovered for further use. The diethyl sulfate is washed with a dilute solution of sodium carbonate and then several times with cold water, then dried with anhydrous sodium sulfate, yielding 32.4 grams.
Reference: JACS 46, 999-1001 (1924)