Premium
Facilitated Transport of Salts by Neutral Anion Carriers
Author(s) -
Chrisstoffels Lysander A. J.,
de Jong Feike,
Reinhoudt David N.
Publication year - 2000
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/(sici)1521-3765(20000417)6:8<1376::aid-chem1376>3.0.co;2-i
Subject(s) - ion , chemistry , organic chemistry
Partitioning of ions from water to the membrane solvent (NPOE) can be quantified by Gibbs free energies of transfer, Δ G tr,NPOE (ion). These were derived from transport studies of lipophilic salts through supported liquid membranes (SLMs) in the absence of the carrier. Partition coefficients K p for various salts can now be calculated. The neutral anion receptors uranyl sal(oph)enes 1 – 5 transport Cl − and H 2 PO as tetrapropylammonium salts. The transport is diffusion‐limited and can be described by two transport parameters D m and K ex . From the extraction constants K ex and the partition coefficients K p of the transported salts, the association constants K a of the anion receptors for Cl − and H 2 PO in NPOE were determined. Competitive transport with carriers 3 and 4 of NPr 4 H 2 PO 4 and NPr 4 Cl demonstrated highly selective transport of H 2 PO even in the presence of excess of Cl − .