Investigation of ionic liquids for efficient removal and reliable storage of radioactive iodine: a halogen-bonding case.

A series of ionic liquids (ILs) were investigated for removal and storage of radioactive iodine (I2) waste released by nuclear power plants. The I2 removal efficiency of ILs was dependent upon the anion species while cation species seemed to have little influence. Particularly, the I2 removal efficiency of [Bmim][Br] was higher than 96% in 5 hours. The nitrogen gas sweeping tests showed that [Bmim][Br] holds I2 tightly, and the leak of I2 from it was negligible under daily life conditions. Spectroscopy studies indicated that high removal efficiencies and storage reliability of ILs were attributed to halogen bonding (XB).