Sorption of Anionic Dyes by Polyampholyte Hydrogels Based on Hydrolized Polyacrylamide Modified with Aliphatic Diamines

Abstract—A study is performed of the sorption of anionic dyes indigo carmine and pyrazolone yellow by polyampholytic hydrogels based on hydrolyzed polyacrylamide modified with aliphatic diamines. It is found that hydrogels have a stronger sorption capacity with respect to indigo carmine (40–129 mg/g). It is shown that the interaction between dyes and hydrogels proceeds according to a mechanism of physical sorption (E < 0–4 kJ/mol). Molecular dynamics modeling of the interaction between the anions of the dyes and the macromolecules of polyampholytic hydrogel based on ethylenediamine shows that hydrogen bonds can form between them.