10.22184/2227-572X.2025.15.2.148.155

The article presents the results of studies of acid-base properties of polymer sorbents based on rhodanine derivatives: polystyrene-azo-o-phenol-­azorhodanine (PAFAR), ARA‑8p-p-carboxybenzene azorodane (ARA‑8p-p-­KBAR) and AN‑31‑p-carboxybenzene azorodane (AN‑31‑p-­KBAR). The sorption capacity of the sorbents for sodium ion and ionization constants of functional-­analytical groups of sorbents were determined by potentiometric titration. The calculated values of sorption capacity for sodium ion for PAFAR, AN‑31‑p-­KBAR and ARA‑8p-p-­KBAR were 3,87 mmol/g, 13,27 mmol/g and 9,67 mmol/g, respectively. The values of the ionization constants of the functional groups of the sorbents were also calculated: for PAFAR – ​pK1 = 8,21 and pK2 = 9,39; AN‑31‑p-­KBAR – ​pK1 = 9,21 and pK2 = 10,16; ARA‑8p-p-­KBAR – ​pK1 = 10,26 and pK2 = 10,80.