Comparison of some organic and inorganic ion exchangers concerning the sorption of Ce(III), Te(IV), Zr(IV), Hf(IV) and Nb(V)

The sorption behaviors of Ce(III), as a representative of trivalent lanthanide ions, and Te(IV), Zr(IV) and Nb(V) as fission products representatives, as well as Hf(IV), from various aqueous media on some synthesized inorganic exchangers, as well as commercially available organic ion exchangers were studied and compared. Organic cation exchanger Dowex-50WX8 and organic anion exchangers AG-1X8 and AG-2X8 were utilized. Synthesized inorganic ion exchangers were zirconium titanium phosphate (ZrTiP) of different Zr:Ti mole ratios and ceric tungstate (CeW). The sorption was carried out from mineral acid solutions as well as EDTA and DTPA solutions. The radioactive isotopes, 95Zr, 95Nb, 123mTe, 141Ce and 181Hf were used to trace the sorption behaviors of the corresponding elements, which were studied in mixtures of them. The differences between the sorption behaviors of the studied metal ionic species on both kinds of ion exchangers were interpreted and discussed in this work.

Preparation, structural characterization, and evaluation of ion-exchange behavior of a new polyoxometalate, [Me2NH2]3[Mo12O40S] in separation of carrier-free 90Y from 90Sr

A new ion-exchanger having chemical formula [Me₂NH₂]₃[Mo₁₂O₄₀S] and belonging to the class of Keggin type polyoxometalate was synthesized and characterized by single-crystal X-ray structure determination. The crystal of the exchanger is rhombohedral, space group R-3 with cell dimensions, a =16.504(18) Å, b =16.504(18)Å (1) Å, c =25.23(3)Å and α=90.00°, β=90.00°, γ=120.00° and Z =6, 3.284gcm^-3. The compound behaves as an ion-exchanger and it is significantly stable towards thermal, chemical environments and total radiation dose of 35.0kGy. Radiochemical separation of the short-lived daughter carrier-free ⁹°Y (T_1/2 =64.08h) from its long-lived parent ⁹⁰Sr (T_1/2 =29 a) using this material at pH 6.0 with 1.0% EDTA solution as an eluent.