IJAMSC  Vol.2 No.2 , June 2014
Influence of Co-Solvent on the Extraction Behaviour of Uranium and Thorium Nitrates with Organophosphorous Compounds
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.


Cite this paper
Pitchaiah, K. , Sujatha, K. , Brahmmananda Rao, C. , Sivaraman, N. , Srinivasan, T. , Nagarajan, K. and Vasudeva Rao, P. (2014) Influence of Co-Solvent on the Extraction Behaviour of Uranium and Thorium Nitrates with Organophosphorous Compounds. International Journal of Analytical Mass Spectrometry and Chromatography, 2, 33-42. doi: 10.4236/ijamsc.2014.22004.
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