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Abstract  

γ-Zirconium phosphate-phosphite, γ-Zr·PO4·H2PO3·2H2O, (γ-ZrPP), was prepared and characterized. Direct treatment of γ-zirconium phosphate-phosphite with an ethanol solution of 0.1M 1,10-phenanthrolin and 2,2'-bipyridyl gave the well defined composites, γ-Zr·PO4·H2PO3(phen)0.15·H2O and γ-Zr·PO4·H2PO3(bipy)0.18·0.6H2O respectively.K d values of a mixture of lanthanide ions: La3+, Sm3+, Eu3+ and Yb3+ for the intercalated products and for γ-ZrPP in HNO3 solution at room temperature and at pH 2 and 4 were determined by a radiotracer technique.140La,152mEu,153Sm and175Yb radioisotopes were used for the equilibration experiment using 500 μl (4.0·10−5 mmole) each of the solutions of the tracers as a mixture in 7.5 M HNO3 solution at the desired pH with 0.1 g of γ-ZrPP and of the intercalated products. The selectivity order was found to be dependent on the nature of the ligand and on the pH. The 2,2'-bipyridyl product posseses, at pH 2 in general, a highK d value, specially for Sm3+ (9815.9) compared to that of the 1,10-phenanthrolin product (3375.5) and to γ-ZrPP (419.8). This could be attributed to partial deintercalation of the 2,2'-bipyridyl at pH 2 and increasing of ionogenic groups.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
S. Shakshooki
,
E. Arafa
,
F. Siala
,
M. El-Mellah
,
S. El-Hamruni
,
A. Bejey
, and
F. Beshewa

Abstract  

Glassy tin arsenate, Sn(HAsO4)2·2.7H2O (SnAs) was prepared and characterized. The uptake of lanthanide ions La3+, Sm3+, Eu3+, and Yb3+ was followed on the glassy tin arsenate in HNO3 solution at pH 1,2 and 4. The radiotracers are140La,153Sm,152mEu, and175Yb. 500 μl (4.0·10−5 mmole) of each solution of the tracer as a mixture plus 7.5 ml HNO3 solution at the desired pH were equilibrated with 0.1g of SnAs. The selectivity order (K d values) was found to be dependent on the pH. At pH 2 theK d values were high for all the studied metal ions [Yb (2065.4)>La (1976.1)>Sm (1826.4)>Eu (1754.4)]. TheK d values at pH 1 and 4 are quite low for all the metal ions studied. At pH 1 they range from ≈144 to 156 and at pH 4 they range from ≈70 to 79.

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