Process for the preparation of methionine

A process for producing methionine, the process comprising contacting a solution or suspension comprising at least one selected from the group consisting of 2-amino-4-(methylthio)butanenitrile and 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 225+/−10% to 300+/−10% m2/g measured according to DIN ISO 9277-5 (2003), a mean maximum Feret diameter xFmax, mean of 3+/−10% to 40+/−10% nm, a mean minimum Feret diameter xFmin, mean of 2+/−10% to 30+/−10% nm, and a mean aspect ratio xFmin, mean/xFmax, mean of 0.55+/−10% to 0.80+/−10%, each measured according to DIN ISO 9276-6 (2012).