| 摘要 |
1,179,630. Separation of acetonitrile from unsaturated nitriles. STANDARD OIL CO. 1 May, 1967 [2 May, 1966], No. 20125/67. Heading C2C. A process for separating acetonitrile from anα,#-mono-olefinically unsaturated nitrile in solution comprises: (a) absorbing a vapour mixture comprising acetonitrile and the unsaturated nitrile ina solvent, (b) feeding the liquid obtained from the step (a) into a stage in the upper half of a multiplicity of intercommunicating extractive distillation stages, (c) removing crude unsaturated nitrile from the condensed overhead vapours withdrawn from the uppermost of the extractive distillation stages, (d) withdrawing a liquid from the lowest of the extractive distillation stages and introducing it into a stage in the upper half of a multiplicity of intercommunicating, countercurrent contacting stages, (e) withdrawing overhead vapours from the uppermost of the countercurrent stages and recovering crude acetonitrile from the condensed acetonitrile vapours, (f) withdrawing a first lean solvent stream from the lower section of the countercurrent stages and returning it to the step (a), and (g) withdrawing a second solvent stream from the lowest of the countercurrent stages, recycling the major portion of said second stream to a stage in the upper half of the extractive distillation stages and disposing of the remainder. In a specific example acetonitrile and acrylonitrile are separated using water as the solvent, a suitable form of apparatus for carrying out the process being described. |
