Extraction of Uranium From Nitric Acid Medium by TBP in Room-Temperature Ionic Liquids

The extraction of uranium from nitric acid medium by TBP in room-temperature ionic liquids(RTIL) based on imidazolium ion,such as 1octyl-3-methylimidazolium hexafluorophosphate(),and 1-butyl-3-methylimidazolium hexafluorophosphate(),and on tetraalkylammonium ion,such as trioctyl methyl ammonium chloride(),was studied.The distribution ratio for extraction of uranium by TBP-RTIL was found to increase with increase of intial nitric acid concentration.Although performance of TBP- system is a little better than those of the two TBP- systems,none of these three is superior to TBP-isooctane system.The experimental results indicate that the extracted uranium could be completely stripped by aqueous guanidinium carbonate solution from the TBP-RTIL phases.Recycle experiments show that no appreciable decline in the extraction and stripping efficiency is observed after 5 extraction-stripping cycles,and thus TBP-RTIL could be reused.