| 摘要 |
1,207,060. Electrochemical dimerization of acrylonitrile. MONSANTO CO. 22 Jan., 1968 [30 Jan., 1967], No. 3266/68. Heading C2C. [Also in Division C7] A process of removing hydrolysed polyacrylonitrile from an aqueous mixture consisting essentially of a quaternary ammonium salt, adiponitrile, acrylonitrile and hydrolysed polyacrylonitrile, is characterized by maintaining the mixture at a temperature up to 45‹ C. and for at least an hour (e.g. in a decanter) to form a water phase and an organic phase, the phases being separated by an interface, and withdrawing a portion of the interface as the hydrolysed polyacrylonitrile. This process is primarily suitable for improving the efficiency of the electrolytic dimerization of acrylonitrile to adiponitrile by removing the hydrolysed polyacrylonitrile by-product which if present will foul the cathode. The portion of the interface removed may be filtered to remove the hydrolysed polyacrylonitrile and the filtrate may then be passed back into the water phase. The preferred temperature of the mixture in the decanter is from 20‹ C. to 35‹ C., the desired pH from 2À5 to 7À5. |
