Evonik Operations Gmbh

Anja Nordschild

Cornelia Borgmann

Axel Ronneburg

Christian Renner

Lucas Geist

Achim Fischer

Christian Reus

Harald Jakob

Martin Koerfer

Stephan Rautenberg

Martin Körfer

Jürgen Bilz

Judith Hierold

Thorsten Merker

Christian Kaiser

Sascha Ceylan

Rainer Malzkorn

Juergen Bilz

The present invention relates to a process for the preparation of methionine comprising the step of contacting a solution or suspension comprising 2-amino-4-(methylthio)butanenitrile and/or 2-amino-4-(methylthio)butaneamide with water in the presence of a catalyst to give a methionine comprising mixture, wherein the catalyst comprises CeO2 comprising particles, wherein the CeO2 comprising particles have a BET surface area of from 175 to 300+/−10% m2/g measured according to DIN ISO 9277-5 (2003), a mean maximum Feret diameter x, mean of from 3+/−10% to 40+/−10% nm and a mean minimum Feret diameter x, mean of from 2+/−10% to 30+/−10% nm, both measured according to DIN ISO 9276-6 (2012).

Process for the preparation of methionine

The present invention relates to a process for the preparation of methionine comprising the step of contacting a solution or suspension comprising 2-amino-4-(methylthio)butanenitrile and/or 2-amino-4-(methylthio)butaneamide with water in the presence of a catalyst to give a methionine comprising mixture, wherein the catalyst comprises CeOcomprising particles, wherein the CeOcomprising particles comprise from 50 to 100 wt.-% of CeO, have a BET surface area of from 35 to 65 m/g measured according to DIN ISO 9277-5 (2003), a mean maximum Feret diameter xof from 10 to 40 nm and a mean minimum Feret diameter xof from 5 to 30 nm, both measured according to DIN ISO 9276-6 (2012).

The present invention relates to a method for preparing 3-methylthiopropionaldehyde by reacting methyl mercaptan with acrolein, in which deviations in the stoichiometry of methyl mercaptan to acrolein in the reaction to give 3-methylthiopropionaldehyde are compensated for by supplying or by forming 1,3-bis(methylthio)-1-propanol, and also to the use of 1,3-bis(methylthio)-1-propanol as a storage form of methyl mercaptan and/or 3-methylthiopropionaldehyde.

Method for preparing 3-methylthiopropionaldehyde

Growing community of inventors

Oberursel, Germany

Anja Nordschild