TRANSPORT STUDIES OF IODINE THROUGH LIQUID MEMBRANE SYSTEM

Transport of iodine by a charge-transfer mechanism through a bulk orga nic liquid membrane system containing calixarene based on donor-type c arriers was studied. It was found that the transport of iodine is faci litated by n-donor carriers depending on the pH of the source phase. T he color of iodine solutions on the source side turned from brown to c olorless. The passage of iodine through the organic bulk liquid membra ne was governed by donor-acceptor interaction between n-donor atoms in the carrier and sigma-acceptor (iodine atoms) and by the diffusion of an n-sigma-type charge-transfer complex in the membrane followed to r elease by the Lewis acid-base interaction in the aqueous phase. The tr ansport by the new carrier arises both from the different extraction e quilibrium constants between the aqueous phase and donor-acceptor inte raction with iodine and the carrier in the organic phase. (C) John Wil ey & Sons, Inc.