Recovery and purification of olefinic nitriles
AssigneeThe Standard Oil Company
InventorHsin C. Wu
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Abstract
A process is described for the recovery and purification of an olefinic nitrile, such as methacrylonitrile, from mixtures of said olefinic nitrile with hydrogen cyanide, acetonitrile, acrylonitrile, and carbonyl compounds, which result from the ammoxidation of an olefin, such as isobutylene. The mixtures of olefinic nitrile are fed to an extractive distillation column at a point above the middle of the column, a vapor sidestream is removed at a point below the middle of the extractive distillation column said sidestream containing substantially all of the hydrogen cyanide, acetonitrile and carbonyl compounds and then concentrating the hydrogen cyanide, acetonitrile and carbonyl compounds in a stripping pot.
Claims6
In the process for the recovery of an olefinic nitrile from a mixture of said olefinic nitrile and other olefinic nitriles, hydrogen cyanide, acetonitrile, and carbonyl compounds, said mixture being produced by the ammoxidation of an olefin, the improvement comprising
- (a) feeding to an extractive distillation column equipped with several fractionating trays at a point above the middle of the extractive distillation column a mixture of the olefinic nitrile, hydrogen cyanide, acetonitrile, and carbonyl compounds,
- (b) feeding solvent water to the extractive distillation column at a temperature in the range of 60.degree. F. to 120.degree. F., and
- (c) removing a vapor sidestream at a point below the middle of the extractive distillation column, and removing from said sidestream substantially all of the hydrogen cyanide, acetonitrile and carbonyl compounds.
Dependencies are inferred from the claim text.