Meta-analysis of Stoichiometric Changes Before and After the Critical Micelle Concentration Within Lanthanide Solvent Extraction

A dataset derived from 35 sources was used to analyze the changes to acid:extractant and metal:extractant stoichiometric ratios as a function of aqueous acid concentration. The presence and location of the critical micelle concentration is easily identified by sharp changes to the stoichiometric ratios. This is consistent with the proportional increase in aggregate size of extractants surrounding a polar core containing extracted metals. Statistical consistency across the dataset allows for elucidation of outliers, the location of previously unreported CMC conditions, and improved CMC values relative to individual studies. Data dense vs. sparse regions of the composition space are identified and the impact this has upon meta-analysis of extraction data is discussed.