METHOD OF MODIFYING SORBENTS BASED ON CELLULOSE FOR EXTRACTING HEAVY METAL IONS FROM AQUEOUS SOLUTIONS Russian patent published in 2024 - IPC B01J20/30 C02F1/62 B01J20/24 

FIELD: various technological processes.

SUBSTANCE: invention relates to methods of modifying natural cellulose-containing sorbents intended for extracting heavy metal ions by sorption from solutions of different composition. Disclosed is a method of modifying sorbents based on cellulose for extracting heavy metal ions from aqueous solutions by two-step treatment of a sorbent selected from cotton or wood cellulose, short flax fibre, sawdust or stalks of topinambur, where at the first stage treatment is carried out with a solution of an oxidant selected from sodium metaperiodate, iodic acid or sodium hypochlorite, at oxidant concentration of 0.1–0.3 M, at solution pH of 2.5–4.5, at solution/sorbent modulus of 15–50, at temperature of 40–55 °C for 2–4 hours, to content of aldehyde groups in sorbent 10–12%, and at the second stage, the oxidised sorbent is treated with 1–7 wt.% taurine solution at pH 8–10 at temperature of 55–70 °C for 30–60 min at solution/sorbent module 15–50 with subsequent washing with water after each stage.

EFFECT: high degree of extraction of heavy metal ions.

1 cl, 1 tbl, 5 ex