Highly selective separation of plutonium using a mono-amide-based supported liquid membrane

A monoamaide-functionalized supported liquid membrane was developed and employed for efficient and selective solid phase separation of Pu(IV). The membrane was prepared in a simple, one-pot process and was characterized for its homogeneity, stability and hydrophobicity. Various membrane parameters like sorption efficiency, sorption kinetics, sorption isotherm and equilibrium uptake capacity were studied for Pu(IV) in nitric acid medium. Langmuir and Freundlich isotherm models were employed for understanding the sorption mechanism of the membrane. Lagergren first-order kinetics and pseudo-second-order kinetics were applied to understand the plutonium sorption kinetics. The equilibrium sorption capacity of the membrane was found to be 27.18 mg g−1and the sorption kinetics followed a pseudo-second-order reaction with rate constants of 1.129 g mg−1 min−1 for Pu(IV). Stripping of Pu from the membrane was also studied to check the regeneration and reusability of the supported liquid membrane. The membrane was found to be very selective toward Pu(IV) in 4 M HNO3 medium, with separation factors 42 and 75 with respect to Am(III) and U(VI), respectively.