Verfahren zur Trennung von wasserloeslichen aliphatischen Alkoholen mit 1 bis 3 Kohlenstoffatomen und deren Essigsaeureestern

摘要

Methanol and methyl acetate are separated from each other by adding water to the mixture, extracting the mixture with methylene chloride, which forms during the subsequent distillation an azeotropic mixture of minimum boiling-point with the methanol and water present, distilling the non-aqueous methyl-acetate-containing extraction layer to leave behind the methanol-free methyl acetate and recovering methanol from the aqueous methanol-containing extraction layer by distillation. In the extraction one part by volume of methyl acetate and methanol mixture is extracted by using 1 part by volume of methylene chloride and 0.75 part of water. Three extraction stages are generally sufficient to bring 93% of the methanol into the aqueous layer and 94% of the methyl acetate into the methylene chloride layer. During the distillation of the methylene chloride layer the methyl acetate remains in the still. The alcohol is recovered from the aqueous extract by distillation in the usual manner. There is obtained as forerunnings a mixture of the ester, alcohol and methylene chloride, which is returned to the extraction.ALSO:Methanol and methyl acetate are separated from each other by adding water to the mixture, extracting the mixture with methylene chloride, which forms during the subsequent distillation an azeotropic mixture of minimum boiling-point with the methanol and water present, distilling the non-aqueous methyl acetate-containing extraction layer to leave behind the methanol-free methyl acetate and recovering methanol from the aqueous methanol-containing extraction layer by distillation. In the extraction one part by volume of methyl acetate and methanol mixture is extracted by using 1 part by volume of methylene chloride and 0.75 part of water. Three extraction stages are generally sufficient to bring 93% of the methanol into the aqueous layer and 94% of the methyl acetate into the methylene chloride layer. During the distillation of the methylene chloride layer the methyl acetate remains in the still. The alcohol is recovered from the aqueous extract by distillation in the usual manner. There is obtained as forerunnings a mixture of the ester, alcohol and methylene chloride which is returned to the extraction.