Process for the commercial preparation of lower amino acids

摘要

A commercial process for preparing glycine or alpha-alanie which consists of carrying out in successively disposed vessels the steps of introducing gaseous ammonia into an aqueous solution of glycolonitrile or lactonitrile to form an aqueous solution containing glycinonitrile or alpha-aminopropionitrile, hydrolyzing the resulting aqueous solution with an aqueous alkaline solution to obtain an aqueous solution of the corresponding alkali metal salt of a lower amino acid, treating the resulting aqueous solution with a mineral acid or its ammonium salt to obtain an aqueous solution containing a free lower amino acid and an alkali metal salt of a mineral acid, and thereafter submitting this aqueous solution to fractional crystallization in the presence of ammonia to isolate and recover the corresponding lower amino acid.