Process for the isolation of colourless formic acid from acetic acid-containing oxidation products of paraffinic hydrocarbons or mixtures thereof with cycloaliphatic hydrocarbons

摘要

Formic acid is separated from acetic acid, isopropenyl methyl ketone and other components present in the oxidation products of aliphatic and cycloaliphatic hydrocarbons, by submitting the anhydrous oxidation mixture to distillation in a fractionating column in the presence of 1-chlorobutane. A mixture of formic acid and 1-chlorobutane distils over, and the condensate separates into two layers. The formic acid layer is purified by distillation in a second column, and the entrainer layer is returned to the head of the first column. The mixture withdrawn from the base of the first column contains substantially all the acetic acid and isopropenyl methyl ketone present in the original mixture.