| 摘要 |
A mixture of isobutyronitrile and isobutyl alcohol is produced by passing isobutyl isobutyrate vapour and ammonia through separate tubes into a reactor containing gamma alumina catalyst, maintained at a temperature of 350 DEG to 500 DEG C. The effluent vapours from the reactor are quenched with water, and the mixture of condensate and water is led to a decanter. The organic phase, which separates in the decanter, is submitted to azeotropic distillation (see Division B1) in order to separate isobutyronitrile, isobutyl alcohol, and unreacted isobutyl isobutyrate.ALSO:isobutyl alcohol is separated from admixture with isobutyronitrile by adding sufficient benzene to the mixture to form an azeotropic mixture of benzene with all the isobutyl alcohol, and distilling off the azeotropic mixture leaving a residue of isobutryonitrile. The method is suitable for separating the mixture obtained by the action of ammonia on isobutyl isobutyrate in the presence of an alumina catalyst. The vapours from the reactor are condensed by direct contact with water; and the mixture of condensate and water is passed to a decanter, where an organic phase separates from an aqueous phase. The organic phase is distilled with benzene in a column, the head of which is maintained at 70 DEG C. so that an azeotropic mixture of water and benzene distils over. The anhydrous liquid withdrawn from the base of the column is distilled, with more benzene, in a second column the head of which is maintained at 80 DEG C. so that the azeotrope of isobutyl alcohol and benzene distils over. A mixture of isobutyonitrile and isobutyl isobutyrate is withdrawn from the base of the second column, and purified isobutyronitrile is separated from it by fractional distillation. The mixture of isobutyl alcohol and benzene, obtained as distillate from the second column, is separated into its components by azeotropic distillation, using water as auxiliary agent. |
