| 摘要 |
Aliphatic dinitriles containing 4-22 carbon atoms, having at least 2 carbon atoms between the nitrile groups, and having, apart from the nitrile groups, a hydrocarbon structure, are purified by bringing them in the presence of water into contact with an alkali metal bisulphate, ammonium bisulphate, an ammonium bisulphate N-substituted by 1-3 alkyl groups having 1-4 carbon atoms, or a bisulphate of a divalent metal which does not form a sulphate which is difficulty soluble in water, e.g. iron, manganese, zinc, cobalt and nickel. The amount of water is preferably 3-8% by weight of dinitrile, and the amount of bisulphate preferably 0.01-10% by weight of dinitrile. Specified dinitriles are adipodinitrile, suberodinitrile, sebacodinitrile and the mixture of 1.9- and 1,10-dicyanoheptadecane known as heptadecane dicarboxylic acid dinitrile. The temperature may be from the solidification point of the dinitrile to 200 DEG C. or more. The purified dinitriles may be reduced to the corresponding diamines. |
