PURIFICATION OF ETHYL ACETATE FROM MIXTURES COMPRISING ETHANOL AND WATER BY PRESSURE SWING DISTILLATION

摘要

A process is described for the recovery of substantially pure ethyl acetate from a feedstock comprising ethyl acetate, ethanol and water. This uses a first distillation zone maintained under first distillation conditions effective for distillation therefrom of a first distillate comprising ethyl acetate, ethanol, and less than about 10 mol % water. The first distillate is recovered from the first distillation zone and is supplied to a second distillation zone maintained under second distillation conditions which include use of a higher pressure than that of the first distillation zone, which are effective for distillation therefrom of a second distillate comprising ethanol, water, and a minor proportion of ethyl acetate and which yield a substantially pure ethyl acetate bottom product, which is recovered. The second distillate is returned to the first distillation zone. A typical feedstock to the process contains less than about 20 mol % water which is supplied to the first distillation zone. Typically the first distillation zone is operated at a pressure of less than about 4 bar (2 x 105 Pa), while the second distillation zone is preferably operated at a pressure of from about 9 bar (9 x 105 bar) absolute to about 15 bar (1.5 x 106 Pa) absolute. IMAGE