Extraction of copper(II) from sulfuric acid by macrocycle-synergized cation exchange: Comparing a novel impregnated resin with its solvent-extraction analog

Abstract

A novel extractive resin employing the tetradentate macrocyclic ionophore tetrathia-14-crown-4 (TT14C4) has been demonstrated via impregnation of strong-acid poly(styrene-divinylbenzene) cation-exchange beads. Following uptake of several weight percent TT14C4, the sulfonic acid resin exhibits a 10-100-fold enhancement in the cation-exchange extraction of Cu(II) as expressed by the Cu(II) distribution coefficient (D[sub Cu]). Since extraction of Cu(II) by unfunctionalized poly(styrene-divinylbenzene) impregnated with TT14C4 was too low to be detectable, the enhancement in cation exchange may be attributed to a synergistic effect involving coordination of the Cu(II) by the mobile macrocycle and cation exchange by the immobile sulfonic acid groups. This is the first demonstration of synergism in a solvent-impregnated resin involving a functionalized support. 45 refs., 5 figs., 2 tabs.