Complexing properties of α-isosaccharinate: thorium

The complexation of Th with α-isosaccharinate has been studied using liquid–liquid-extraction techniques. An organic phase consisting of 0.025 M acetylacetone in toluene was used with a 1.0 M NaClO4 aqueous phase kept at pH 8 in a thermostated AKUFVE unit at 25 °C. The concentration of α-isosaccharinate (ISA-) in the aqueous phase was incrementally increased and samples of equal volumes were taken from the two phases and analyzed in a liquid scintillation detector. Stability constants, β pt, for the complexation reaction Th4++p ISA-↔Th(ISA)p(4-p)+, were determined to be logβ125°C=12.56±5.01, logβ225°C=19.38+0.35/-0.95, and logβ325°C=21.30±0.26.

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