Facilitated transport of uranium(VI) across supported liquid membranes containing T2EHDGA as the carrier extractant

作者：Panja S; Mohapatra P K^*; Tripathi S C; Manchanda V K

来源：Journal of Hazardous Materials, 2011, 188(1-3): 281-287.

DOI：10.1016/j.jhazmat.2011.01.109

• Uranium
• Liquid membrane
• T2EHDGA
• Facilitated transport
• Actinide partitioning

Facilitated transport of uranyl ion from nitric acid feed solutions was investigated across PTFE supported liquid membranes using N,N,N',N'-tetra-2-ethylhexyl-3-pentane-diamide (T2EHDGA) in n-dodecane as the carrier extractant containing 30% iso-decanol as the phase modifier. Solvent extraction studies indicated extraction of species of the type, UO2(NO3)(2)center dot T(2)EHDGA. The distribution coefficients increased in the presence of NaNO3 as compared to equivalent concentration of HNO3 which was exactly the opposite of what was reported for Am(III)-TODGA extraction system. Supported liquid membrane studies indicated about 11 h were required for quantitative transport of U(VI) from a feed of 3 M HNO3 using 0.2 M T2EHDGA in n-dodecane containing 30% iso-decanol as the carrier extractant. Effect of various parameters such as feed acidity, T2EHDGA concentration, and nature of the strippant on the transport rate was investigated. The transport was found to be diffusion controlled in the membrane phase and the permeability coefficient was calculated to be (3.20 +/- 0.13) x 10(-4) cm/s for the feed composition of 3 M HNO3, receiver phase composition of 0.01 M HNO3 and membrane carrier phase of 0.2 M T2EHDGA in n-dodecane containing 30% iso-decanol. The present results may be useful for the separation of U from lean solutions or radioactive wastes considered hazardous due to the presence of alpha-particle emitting radionuclides.

• 出版日期2011-4-15