Selective sorption and column concentration of alkali-metal cations by carboxylic acid resins with dibenzo-14-crown-4 subunits and their acyclic polyether analogs

Abstract

Alkall-metal cation sorption from aqueous and aqueous methanolic solutions and column concentration of alkall-metal cations from dilute aqueous solutions by carboxylic acid resins containing dibenzo-14-crown-4 units and their acyclic polyether analogues have been investigated. The crown ether carboxylic acid resins exhibit enhanced sorption selectivity over the acyclic polyether resins. Good sorption selectivity over the acyclic polyether resins. Good sorption selectivity for LI+ and Na+ was obtained with a cyclic polyether resin in which the carboxylic acid group is positioned over the crown either ring. For column concentration of alkali-metal cations from dilute aqueous solutions, gradient elution of the sorbed metal ions from the resin with the carboxylic acid group positioned over the crown either cavity gave selective column concentration of Li+ and Na+.