Liquid–liquid extraction of U(VI) using malonamide in room temperature ionic liquid

The extraction behavior of U(VI) from nitric acid medium by a solution of N , N -dimethyl- N , N -diphenylmalonamide (DMPMA) in the ionic liquid, BmimPF 6 , was studied. The extractability was measured as a function of various parameters such as kinetics, phase ratio, the concentration of DMPMA, nitric acid and sodium nitrate, alkyl chain length of ionic liquid. The extractability from 5 M nitric acid by 0.35 M DMPMA/BmimPF 6 was found to be almost 100 %. Slope analysis of the experimental data suggests that the probable molecular structure of the extraction species is [UO 2 NO 3 (DMPMA) 2 ] + , and the mechanism likely occurs by a cation exchange mode.