At the extractant concentrations studied here, there is a dearth of reported CMC acid concentrations. The critical acid concentrations found in this work are within the range of where the literature reported critical micelle concentration for both TODGA and TEHDGA . In particular, for DMDOHEMA, the literature reports a CMC at been suggested above 0.1 M of DMDOHEMA. We believe that the transition in Fig. refers to the latter. Additionally, this point is also closer to the free acid CMC value at [DM DOHEM A] = 0.43 M in n-dodecane at 25 We next examined different concentrations of the extractants so as to understand trends in the predicted critical acidity, as well as changes to the stoichiometric acid:extractant coefficient. For 0.2 M TODGA, the dataset spans 0.5 -3.5 M HNO 3 , while yields an excellent single line fit with R 2 ≈ 0.98, and an average stoichiometry of 1 HNO 3 :TODGA.