Synergistic extraction of americium(III) with 2-thenoyltrifluoroacetone and crown ethers

Extracton, of Am3+ in benzene with 2-thenoyltrifluoroacetone (HTTA) and crown ethers (CEs) such as 15-crown-5, 18-crown-6, dicyclohexano-18-crown-6, dibenzo-18-crown-6, dicyclohexano-24-crown-8, and dibenzo-24-crown-8 was investigated. Synergistic effect by CE was observed regardless of the kind of CE examined. The extracted species was found to be Am(TTA)3(CE), and adduct formation constants between Am(TTA)3 and CE in the organic phase were determined. The sequence of constant could not be explained only by basicity of CE and the steric effect of CE should be taken into account to elucidate the adduct complex formation.