Radiation Syntheses of Poly(Acrylamide)/Poly(Ionic Liquid) Gels for Adsorption of Uranyl and Iodide Ion

In order to remove uranyl and iodide ions from aqueous radioactive waste, poly (acrylamide)/poly(ionic liquid) hydrogels (PAm-C_nvim₂Br₂) were prepared by γ-radiation induced polymerization and crosslinking. A high gel fraction value of about 95% can be achieved under 5 kGy, and the equilibrium degree of swelling can be adjusted by absorbed dose. The resultant PAm-C_nvim₂Br₂ can strongly adsorb uranyl ion with an adsorption capacity as high as about 130 mg/g (U/gel) from carbonate solutions, or iodide ion with an adsorption capacity as high as about 160 mg/g (I/gel) from sodium iodide solution, following a Langmuir model. IR and XPS analyses indicate that it is an ion exchange mechanism. PAm-C_nvim₂Br₂ hydrogels have excellent adsorption and desorption performances for uranyl and iodide ion, and it is expected to be used in the disposal of aqueous radioactive waste.