extractive distillation process for separating mixtures of alcohols and esters contienment unsaturated carboxylic acids, the format of the azeotrope mixtures.

摘要

Lower alkyl esters of unsaturated aliphatic acids are separated from lower aliphatic alcohols by submitting the mixture to extractive distillation using, as extraction agent, an ester of a b -alkoxycarboxylic acid whereby the alcohol is distilled off leaving a mixture of the unsaturated ester and the extraction agent which is then separated by ordinary distillation. The process is particularly suitable for separating the mixture of an acrylic ester and alcohol obtained by splitting an ester of a b -alkoxy-carboxylic acid. In Example 1, a mixture of methyl acrylate and methanol, stabilized with hydroquinone, is fed into the bottom portion of a column, which is heated to maintain boiling, while methyl b -methoxy-propionate at 70 DEG C. is introduced into the head of the column. Pure methyl acrylate is separated from the sump product by distillation under reduced pressure. Examples 3, 4 and 5 relate to ethyl acrylate, butyl acrylate and methyl methacrylate, respectively.