Performance of Chelating Resins Containing Calixpyrroles in Sorption of Anions

Abstract

Characteristics and sorptive properties of three series of chelating resins having incorporated calixpyrrole ligands within their structures is reported. Two sets of resins were obtained by immobilization of calix[4]pyrrole or calix[4]pyrrole[2]thiophene on the beads of crosslinked (vinylbenzyl chloride)/divinylbenzene copolymer. The third series was synthesized by condensation of calix[4]pyrrole with formaldehyde. All resins displayed sorptive properties towards halide anions and cyanides in a non‐aqueous medium (acetonitrile). The resins displayed superior selectivity for fluoride anions and the selectivity sequence for the uptake of other anions depended on their ionic radii. The bigger ligand, calix[4]pyrrole[2]thiophene, showed an enhanced affinity for bigger anions, including iodide, which was not observed in the case of calix[4]pyrroles. Thus, the resin containing the larger ligand complexes the whole range of anions, but with poorer selectivities.

Keywords:

• Chelating resins
• sorption
• calixpyrroles
• anions

Acknowledgement

The financial support of the Polish Committee for Scientific Research (Grant No. 3 T09B 034 26) is kindly acknowledged.