Combined ion exchange-solvent extraction (CIESE) studies of metal ions on ion exchange papers. Synergistic effects and chromatographic separations

Abstract

excitation temperature of a low level (V: = 0.966 eV) is measured, this level being much less liable to deviations from Boltzmann equilibrium than the higher excitation levels.On the other hand, it should be mentioned that the typical advantages of a null method [i.e., measurements at log (F20/ F2i) = 0] have not been realized. However, according to Snelleman and Alkemade (J), this goal can be achieved by (5) W.

Aqua-Impregnated Resins. 2. Separation of Polyvalent Metal Ions on Iminodiacetic and Polyacrylic Resins Using Bis(2-ethylhexyl) Phosphoric and Bis(2-ethylhexyl) Dithiophosphoric Acids as Organic Eluents

“…Since then, many CIESE systems involving both cation and anion exchangers have been studied. [7][8][9][10][11][12][13][14][15] However, all of them can be eventually characterized by the same extraction mechanism which involves protonation of a CIESE-active component of Lewis base type resulting in the formation of an oxonium salt followed by an interaction of the later with extractable ion from the resin phase due to the formation of ion association complexes in the mobile phase. 6 At the same time, application of CIESE-based separation processes in water-imiscible organic solvents is not known, 16 although the CIESE systems of this type are of practical importance.…”

“…The CIESE concept is based on simultaneous ion-exchange (IX) and liquid−liquid extraction by a bifunctional separation mechanism which occurs in applying CIESE-active organic compounds such as, ethers, ketones, and some others in the presence of mineral acids to selectively elute ions from IX resins. Since then, many CIESE systems involving both cation and anion exchangers have been studied. − However, all of them can be eventually characterized by the same extraction mechanism which involves protonation of a CIESE-active component of Lewis base type resulting in the formation of an oxonium salt followed by an interaction of the later with extractable ion from the resin phase due to the formation of ion association complexes in the mobile phase . At the same time, application of CIESE-based separation processes in water-imiscible organic solvents is not known, although the CIESE systems of this type are of practical importance.…”