Crystals of [S,S]-ethylenediamine-N,N'-disuccinic acid with high bulk density and method of obtaining the same

摘要

Crystals of [S,S]-ethylenediamine-N,N'-disuccinic acid which have a bulk density of 0.45 to 1.2 g/cm3, and a process for obtaining these crystals comprising the steps of adjusting an aqueous solution of an [S,S]-ethylenediamine-N,N'-disuccinic acid metal salt to a temperature of 40 to 80° C. and a pH of 1.9 to 4.5, and cooling the solution to a temperature below 40° C. over a period of 0.2 to 10 hours while supplying a mineral acid so as to maintain the pH at 1.9 to 4.5 to precipitate [S,S]-ethylenediamine-N,N'-disuccinic acid in a high yield.