Transport of lanthanides and fission products through supported liquid membranes containing N,N,N′,N′-tetraoctyl diglycolamide (TODGA) as the carrier

Facilitated transport of trivalent lanthanides, viz. La(III), Eu(III), Lu(III) and several fission product elements such as Tc, Mo, Zr, Pd, I, Cs and Ru across a flat sheet supported liquid membrane made of PTFE impregnated with N,N,N′,N′-tetraoctyl diglycolamide (TODGA) in n-dodecane was investigated from dilute nitric acid solutions. The transport rates of lanthanides increased with nitric acid concentration in a manner similar to their distribution ratios. The trend in metal ion transport after 75 min followed the order: La > Eu > Lu > Zr > Sr > I > Pd ~ Tc > Ru > Mo ~ Cs, which was consistent even after 5 h of operation. However, the transport of I reached the maximum value of ~26% in 100 min and remained constant thereafter. In the case of Am(III) transport studies, excellent decontamination from Zr was achieved when 0.4 M oxalic acid was added to the feed solution.