Bunina Z. Lanthanide ions sorption by polymeric sorbents with immobilized О-dentate ligands

The thesis focuses on the establishment of regularities of lanthanide ions sorptive extraction by a number of polymeric sorbents with immobilized O-dentate ligands. The optimal conditions for the sorption of the ions under study have been determined for all materials. A series of ion-imprinted polymers based on ethylene glycol dimethacrylate or divinylbenzene was synthesized by free-radical bulk polymerization. The high conversion of monomers was confirmed by IR spectra. Polymers with ethylene glycol dimethacrylate as a cross-link agent were found to be macroporous. They are characterized by large surface areas which decrease monotonously with a decrease in the cross-link ratio. Divinylbenzene copolymers have significantly lower specific surface areas which indicates the gel-type nature of the materials obtained. The effect of cross-link ratio, monomers, and ligands for ion-imprinted polymers on sorption properties of polymers obtained with respect to Gadolinium was established. Among ethylene glycol dimethacrylate copolymers the greatest imprinting effect was observed for materials with cross-link ratio of 80.0%mol. Divinylbenzene copolymers with immobilized carminic acid had larger distribution ratios of lanthanides as compared to polymers with immobilized Alizarin red S. This is due to the wider range of choices for nonselective binding in case of carminic acid because of the greater number of oxygen functional groups in its molecule in comparison with Alizarin red S. Divinylbenzene copolymers are characterized by higher sorption capacity than ethylene glycol dimethacrylate copolymers owing to additional stabilization of aromatic ligands via π-π interactions.