Highly selective membrane transport of copper(II) ion by synthetic linear oligomer carriers

Abstract

A new class of synthetic carriers having urea or thiourea units has been shown to extract and to transport transition-and heavy-metal ions with high selectivities. The rates and specificities in this transport system are largely dependent on the carrier structure, the nature of co-transported anions, and other additives. The best carrier, a urea-containing octameric oligomer [–CH₂CH₂N(CONHPh)–]₈(1), provided the first example of completely selective transport of copper ion through a liquid membrane, and a chemical analogue to biological copper transport.