The synergistic extraction of trivalent actinides Am, Cm, Bk and Cf with thenoyltrifluoro acetone (HTTA) and tributyl phosphate
(TBP) has been studied in xylene at 30°C. Correction for the HTTA-TBP interaction has been applied to get the free TBP concentration
in the organic phase. Plots of log D vs. log [HTTA] give straight lines with a slope of 3 only after correcting for the HTTA-TBP
interaction; without this correction the slope varies from 3 to 1 with increasing HTTA concentrations. The presence of two
synergistic species M(TTA)3·TBP and M(TTA)3·2TBP simultaneously has been observed. The equilibrium constants for the organic phase synergistic reactions have been calculated.