PROCESS FOR PREPARING A CRYSTALLINE L-MGDA TRI-ALKALI METAL SALT

摘要

What is proposed is a process for preparing a crystalline L-MGDA tri-alkali metal salt by crystallization from an aqueous solution thereof which has been obtained by Strecker synthesis proceeding from L-a-alanine, by reaction with formaldehyde and hydrogen cyanide to give L-a-alanine-N,N-diacetonitrile and subsequent alkaline hydrolysis of the L-a-alanine-N,N-diacetonitrile to give the L-MGDA tri-alkali metal salt, which is characterized in that a temperature of 150°C is not exceeded in the course of alkaline hydrolysis.