METHOD OF POLYAMINOCARBOXYLATES PURIFICATION Russian patent published in 2017 - IPC C07C229/00 C07C227/42 C07C229/16 C07C229/24 C07D257/02 

FIELD: chemistry.

SUBSTANCE: polyaminocarboxylates purification method comprises the following steps: a) processing aqueous polyaminocarboxylates inorganic acid, wherein the pH value of the solution is less than 0.75; b) recrystallizing the precipitated salt polyamino acid from water or aqueous solvent mixtures; c) treatment of an aqueous salt solution polyamino acid resin or a basic solution to maintain the pH at from 1.5 to 3.0; d) isolation of the pure polyaminocarboxylates as a chelating agent, wherein after step (a) above, the product is precipitated as a salt Polyamino acid; and wherein the precipitated salt Polyamino acid obtained in step (a) above, is isolated by filtration recrystallization before performing step (b).

EFFECT: increase the degree of purification.

9 cl, 2 ex