Abstract :

[4,4,4-trifluoro-1-(5-chloro-2-thienyl)-1,3-butanedione H(5-chloro-TTA) and 4,4,4-trifluoro-1-[5-methyl-2-thienyl]-1,3-butanedione H(5-methyl-TTA) were prepared according to literature. The extraction behavior of H(5-chloro-TTA) and H(5-methyl-TTA) diketones with Uranyl(VI) and Thorium(IV) ions was studied under different experimental conditions; namely, extraction time, ligand concentration, stripping time, stripping acid concentration, pH and temperature. From the distribution coefficients (Kd) at different temperatures, the enthalpy (ΔHº), Gibbs free energy (ΔGº) and entropy changes (ΔSº)associated with extraction processes for these ions were determined.