Pervaporative separation of organic compounds from water during butyl acetate production via esterification

This study deals with the separation of n-butyl acetate, n-butanol and acetic acid from aqueous solutions by pervaporation using a poly (ether block amide) membrane. Separations of binary mixtures were initially investigated. The paper also reports on separation studies of quaternary mixtures composed of all four components that are relevant to n-butyl acetate production by esterification via reactive distillation. It is shown that the membrane is especially selective to n-butyl acetate permeation. For the separation of the quaternary mixtures, the concentration of n-butyl acetate in the permeate was sufficiently high that phase separation occurred in the permeate. This is of particular interest from an industrial application point of view in that the organic phase can be recycled to the distillation column for reprocessing, and the aqueous phase can be recycled to the pervaporation unit for further treatment.