Extraction of Cu, Ni and Co with Sodium Salt of Di-2-ethylhexylphosphoric Acid

Review: Dissociation, Self-Association, and Partition of Monoacidic Organophosphorus Extractants

“…In comparison to that treatment, several circumstances make further development or even improvement of the use of Eqs. [1] and [2] desirable. First, the models of Kamlet & Taft and Leggett assume K d to be introduced into Eqs.…”

“…First, the models of Kamlet & Taft and Leggett assume K d to be introduced into Eqs. [1] and [2] on the mole fraction scale, and this has been made in this review. Second, K d values obtained at I = 0.1 and I = 1.0 were treated together by Apostoluk et al [53] but separately in this review.…”

“…Parameters of Eqs. [1] and [2], as taken for the description of K d by Apostoluk et al [53] and in this review. N is the number of experimental values Table 1 and converted to the mole fraction scale.…”

“…The parameters [P 1 ] to [P 5 ] and [p 1 ] to [p 7 ] will henceforth be called equation parameters, in order to differentiate them from the solvatochromic parameters. Equation [ 2 ] was used by Apostoluk et al [53] without the term [p 4 ]α, i.e., setting [p 4 ] = 0. Equation parameters found with K d expressed on the molar scale are given in Table 4 as presented in the original source, [53] that is, with superfluous decimal places.…”

“…[2] is used for the characterization of K d of a single extractant. Such a less general approach has been used by Tao et al, [20] who treated data on HDEHP and bis(2-methylnonyl) phosphoric acid by the Leggett equation in omitting the intrinsic volume as a variable.…”