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A task specific ionic liquid (TSIL) bearing phosphoramidate group, viz., N-propyl(diphenylphosphoramidate)trimethylammonium bis(trifluoromethanesulfonyl)imide, was synthesized and characterized by H NMR,C NMR, P NMR, and IR spectroscopies, elemental (C H N S) analysis, and electrospray ionization mass spectrometry (ESI-MS). Using this TSIL a cloud point extraction (CPE) or micelle mediated extraction procedure was developed for preconcentration of uranium (U) in environmental aqueous samples. Total reflection X-ray fluorescence spectrometry was utilized to determine the concentration of U in the preconcentrated samples. In order to understand the mechanism of the CPE procedure, complexation study of the TSIL with U was carried out by isothermal calorimetric titration, liquid-liquid extraction,P NMR and IR spectroscopies, and ESI-MS. The developed analytical technique resulted in quantitative extraction efficiency of 99.0 ± 0.5% and a preconcentration factor of 99 for U. The linear dynamic range and method detection limit of the procedure were found to be 0.1-1000 ng mL and 0.02 ng mL, respectively. The CPE procedure was found to tolerate a higher concentration of commonly available interfering cations and anions, especially the lanthanides. The developed analytical method was validated by determining the concentration of U in a certified reference material, viz., NIST SRM 1640a natural water, which was found to be in good agreement at a 95% confidence limit with the certified value. The method was successfully applied to the U determination in three natural water samples with ≤4% relative standard deviation (1σ).

Simultaneous cloud point extraction of uranium and thorium in aqueous samples with the highest reported extraction efficiencies and preconcentration factors.

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Extraction of pure uranium (U) from its ore or spent nuclear fuel and separation of U for trace impurities characterization of nuclear fuels are the processes resulting into the accumulation of large amounts of low boiling and volatile organic waste. The limited reusability and degradation (chemical and radiation induced) of these waste solutions turning out to be an environmental threat. The authors have addressed this issue by developing an eco-friendly, simple and selective liquid-liquid extraction (LLE) procedure for U employing a phosphoramidate group bearing task specific ionic liquid (TSIL). Optimization of various LLE parameters resulted in high distribution ratio (D) value of 174 � 5 for U when extracted from 5 mol L À 1 HNO 3 medium. A detailed study on the infrared and extended X-ray absorption fine structure spectroscopy of U loaded ionic liquid phase reveals the extraction mechanism. Such high D U value resulted in high separation factors for U with respect to the elements which are commonly present in the ore, processed nuclear fuel and spent nuclear fuel. The structural integrity and metal ion extractability of the TSIL is found to remain unaffected when irradiated up to an absorbed dose of 400 kilogray (kGy). Sodium carbonate solution is found to backextract � 95% of U from the ionic liquid phase and regenerate it for further usage.persuing research in this field and we are further working on these directions. Supporting Information SummaryAll the information regarding instruments, optimized instrumental parameters, reagents, solutions and the extraction procedure have been provided in supporting information.