Degussa Aktiengesellschaft

Evonik Degussa Gmbh

Ferdinand Theissen

Klaus Huthmacher

Herbert Tanner

Hans-Joachim Hasselbach

Friedhelm Geiger

Klaus Hentschel

Martin Korfer

Jose Vanrobaeys

Klaus Willigerodt

Sven-Peter Mannsfeld

Baudouin Halsberghe

Klaus Peter Müller

A process for the preparation of methionine or a salt of methionine by reaction of the components 3-methylmercaptopropionaldhyde, hydrogen cyanide, ammonia and carbon dioxide or components from which the above-mentioned components can be prepared, optionally in the presence of water, to 5-(2-methylmercaptoethyl)-hydantoin and further reaction thereof to methionine or the salt thereof, characterised in that the reaction of the components is initiated by means of at least one premixture in such a way that a first mixture is formed containing at least the predominant proportion (at least 5/10) of the 3-methylmercaptopropionaldeyde and at least 1/10 of the hydrogen cyanide component or corresponding quantities of components from which these components can be prepared, and less than 5/10 of one of the components ammonia, carbon dioxide or of the components from which ammonia or carbon dioxide can be prepared, and in that this first mixture is combined with the other component(s) for the reactive conversion to 5-(2-methylmercaptoethyl)-hydantoin, wherein this (these) latter component(s) may be premixed in one or more other mixtures.

Process for the preparation of D,L-methionine or the salt thereof

Growing community of inventors

Bornheim, Germany

Ferdinand Theissen