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has been cited by the following article:

• TITLE: Influence of Co-Solvent on the Extraction Behaviour of Uranium and Thorium Nitrates with Organophosphorous Compounds

  AUTHORS: K. C. Pitchaiah, K. Sujatha, C. V. S. Brahmmananda Rao, N. Sivaraman, T. G. Srinivasan, K. Nagarajan, P. R. Vasudeva Rao

  KEYWORDS: Co-Solvent, Uranium and Thorium, Organophosphorous Compounds

  JOURNAL NAME: International Journal of Analytical Mass Spectrometry and Chromatography, Vol.2 No.2, June 30, 2014

  ABSTRACT: Supercritical Fluid Extraction (SFE) is emerging as a powerful technique in the extraction of metal ions. In the present study, the extraction of nitrates of uranium and thorium was carried out using supercritical carbon dioxide (Sc-CO2) modified with various organophosphorous compounds such as dialkylalkyl phosphonates, trialkyl phosphates and trialkyl phosphine oxides in the presence of co-solvents such as methanol, dichlormethane and n-hexane. The influence of ligand and co-solvent on the extraction of the metal nitrates was studied in detail. These studies have established that co-solvent plays an important role in the extraction as well as fractionation of uranium and thorium nitrates. Polar co-solvent, methanol provided faster extraction without fractionation whereas the non-polar solvent, e.g. n-hexane provided some fractionation of metal nitrates though the extraction kinetics was slower.