METHOD FOR MODIFYING AN ANION EXCHANGE MEMBRANE Russian patent published in 2023 - IPC B01D71/82 

FIELD: membrane technology.

SUBSTANCE: invention relates to methods for modifying anion-exchange membranes in order to improve their characteristics and can be used in the manufacture of membranes for electrodialysis apparatus. A method is presented for modifying an anion-exchange membrane made from a polymer containing amino groups of various degrees of alkylation, including pretreatment of the membrane, followed by its treatment with an aqueous solution of a modifier - a polyelectrolyte of a polymeric nature, which is used as a copolymer of N,N-dimethyl-N,N-diallylammonium chloride and maleic acid, taken in a mass ratio of 1:1, for 8 hours at a temperature of 50°C, while the processing is carried out by pumping 2.5 wt.% aqueous solution of the modifier through the electrodialyzer desalting chamber formed by the modified anion-exchange and auxiliary cation-exchange membrane, concentrating its molecules at the membrane surface during electrodialysis concentration at a current density of 0.75 mA/cm².

EFFECT: invention provides stable characteristics of modified anion-exchange membranes for a longer period of operation in electrodialysis.

1 cl, 2 tbl, 1 ex