GB357581A - A process for the manufacture and production of mono-ethanolamine dinitrate or its homologues - Google Patents

Abstract

Monoethanolamine dinitrate, <FORM:0357581/IV/1> , and its homologues are manufactured by acting while cooling on monoethanolamine or a homologue thereof with excess of concentrated nitric acid and precipitating the dinitrate by pouring the solution into a cooled low molecular aliphatic alcohol or ether or a mixture thereof. Alternatively the base is first neutralized with the calculated amount of dilute nitric acid to produce the nitric acid salt, which is introduced into highly concentrated nitric acid. The excess nitric acid may be recovered by extraction with water when using an ether for the precipitation, or, when an alcohol is employed, by neutralizing, e.g. with aqueous soda solution, and distilling off the alcohol, or preferably in either case by vacuum distillation of the nitration charge before precipitation. In examples: (1) monoethanolamine mononitrate is treated at 0-10 DEG C. with concentrated nitric acid and the solution poured with stirring into 95 per cent ethyl alcohol at 0 DEG to -10 DEG C.; (2) the nitration charge of (1) is poured into pure ethyl ether; (3) the nitration charge is distilled at 35-40 DEG C. under a pressure of 11-12 mm. mercury gauge and the residue poured into 95 per cent ethyl alcohol at -10 DEG to -15 DEG C.; (4) as in (3) but using a mixture of ethyl alcohol and ethyl ether for the precipitation; (5) butanolamine is neutralized with dilute nitric acid, the mononitrate is added to concentrated nitric acid and the resulting solution added to a cooled mixture of ethyl ether and ethyl alcohol. Other, though less suitable, liquids specified for the precipitation are methyl, propyl and butyl alcohols. Specification 350,293 is referred to.