APPLICATION OF DIAZAPOLYOXABICYCLIC LIGANDS TO THE QUANTITATIVE EXTRACTION SEPARATION OF ALKALI AND ALKALINE EARTH METAL IONS AS THE ION-SIZE SELECTIVE MASKING REAGENTS

摘要

Quantitative extraction separations of alkali and alkaline earths have been achieved by adding the macrocyclic ionophores as the masking reagents to the aqueous phase. Diazapolyoxabicyclic ligands (cryptands) were applied as the ion-size selective masking reagents to the synergistic solvent extraction system with benzoyltrifluoroacetone (BFA) and tri-n-butylphosphate (TBP) or tri-n-octylphosphine oxide (TOPO) into cyclohexane. Quantitative extraction separations between magnesium and calcium and between lithium and sodium were achieved with BFA and TBP or TOPO in the presence of cryptand. Calcium could be also quantitatively separated from strontium in the synergistic extraction with BFA and TBP in the presence of cryptand.