Process for the preparation of ethylene diamine

摘要

Ethylene diamine is prepared from hydrogen cyanide, aqueous formaldehyde, ammonia and hydrogen by feeding into the reaction zone one or more streams of the above containing a molar excess of ammonia relative to the hydrogen cyanide or formaldehyde whichever is present in the lesser amount, and heating the mixture at between 90 to 130 DEG C. at 3,000 p.s.i.g., at least, in the presence of a hydrogenation catalyst. The streams are free of hydroxyacetonitrile or aminoacetonitrile and the catalyst may be an activated metal catalyst e.g. nickel or cobalt which may include a promotor, for example a metal of Group IB, IIB, VIB, VIIB, or VIIIB of the Periodic Table. The process may be continuous and either or both the excess ammonia and hydrogen streams may be recycled. Examples describe the continuous process both with, and without, the recycling of the hydrogen and ammonia.