ACID DEPENDENCY OF THE EXTRACTION OF SELECTED METAL-IONS BY A STRONTIUM-SELECTIVE EXTRACTION CHROMATOGRAPHIC RESIN - CALCULATED VS EXPERIMENTAL CURVES

The extraction of selected divalent (Ca+2, Sr+2, Ba+2, Ra+2, Pb+2, UO2+2) and monovalent (Na+, K+, Rb+, Cs+, Tl+) metal cations at tracer concentration level by a recently introduced strontium-selective extraction chromatographic resin has been studied as function of the nitric acid concentration in the range approximately 0.1-7 M underbar. The data have been explained by combining the metal extraction, the acid extraction, and the aqueous phase metal complexation equilibria. Conditional metal extraction equilibrium constants have been estimated by using calculated activity coefficients of the metal nitrate salts in the nitric acid solutions. The extraction constants have been used to predict the effect of macroconcentrations of sample matrix constituents on the extraction of Sr+2 or Pb+2 by the strontium-selective resin.