METHOD OF PRODUCING MODIFIED SORBENT BASED ON CHITOSAN FOR EXTRACTING HEAVY METAL IONS Russian patent published in 2025 - IPC B01J20/30 B01J20/22 B01J20/24 

FIELD: chemistry.

SUBSTANCE: invention relates to chemical industry and specifically to a method of producing a modified sorbent for extracting heavy metal ions from aqueous solutions. Method of producing a modified sorbent for extracting heavy metal ions from aqueous solutions consists in obtaining a solution of chitosan in 1 vol.% acetic acid, its intensive stirring and ultrasound treatment for 20-40 minutes to obtain a homogeneous gel, gradual addition of epichlorohydrin as a cross-linking agent and stirring until its complete inclusion in the reaction mixture to obtain a cross-linked chitosan gel, subsequent drop introduction of prepared gel into aqueous solution of sodium hydroxide with stirring, holding the formed chitosan granules in it for 20-50 minutes, followed by their separation from the dispersion medium and thorough washing with distilled water to neutral pH, according to the invention, the prepared cross-linked and modified chitosan gel is added to an aqueous solution of sodium hydroxide with concentration of 0.1-0.5 M, and the gel of cross-linked chitosan is modified by adding topinambur gel with a weight ratio of chitosan/topinambur 10:1-8:1 and dodecyl dimethylamine-N-oxide in amount of 0.2-0.4 ml per cross-linked chitosan gel, obtained from 20 g of 3% chitosan gel with 0.54 ml of epichlorohydrin, followed by stirring for 5-10 minutes.

EFFECT: invention enables to obtain a sorbent with high sorption capacity with respect to heavy metal ions.

1 cl, 1 tbl, 3 ex