Recently, there has been an increased demand for developing methods that are suitable for separation and trace level determination of uranium from various types of samples including surface waters, food, biological samples and industrial effluents. This demand is two-fold, firstly, because of the large requirement for uranium in the atomic energy programme and secondly due to the very high toxicity of uranium. Serious problem is pollution of Both groundwater and surface water by uranium, which gets seeped from the mining and milling leachates as well as from the normal run-off associated with mining sites. Chemical immobilization, trapping and surface imprinting as enrichment procedure in combination with sensitive instrumental method for quantification are the most used approach uranium determination in various matrices. IIPs are generally prepared from a reaction mixture composed of a functional monomer, a crosslinker, an initiator and a template . IIPs are developed in a similar way to imitate key and lock mechanisms for recognition and removal of the targeted ions. Thus, IIPs offer excellent selectivity and specific affinity for a given ion. The aim of the present study is synthesis and characterization of ion-imprinted polymer sorbents and their application for U determination. Experimental design includes synthesis of polymer matrix using vinyl monomers e.g., methacrylic acid, acrylamide, styrene, 4-vinylpyridine crosslinked by ethylene glycol dimethacrylate or divinylbenzene in the presence of template such as: uranyl ion, 1-(prop-2-en1-yl)-4-(pyridin-2-ylmethyl) piperazine, salicylaldehyde crosslinked in the presence of uranyl template, chitosan. The composition, structure and morphology of the polymer particles obtained are characterized using elemental analysis, FTIR, SEM and BET analyses. The optimal parameters for the quantitative sorption of uranyl ions are defined and the extraction efficiency of synthesized polymers is compared and discussed. The desorption behavior of retained uranyl in the presence of different elution agents: 3M HCl. 2M HNO3, 0.05M EDTA was also studied. Analytical procedure for the determination of kinetically labile uranyl species was developed and characterized (LOQ, RSD, repeatability, selectivity).
Acknowledgements: We acknowledge the Bulgarian Scientific Fund, Project, DN19/10, “Smart speciation”.
- Synthesis of various ion imprinted polymers for uranyl ions.
- Selective sorption of uranyl ions. Determination of kinetically labile uranyl species.
- Simple analytical procedure for selective determination of uranyl in various samples.