| Autor: |
Izatt, Reed M., Lindh, Gypzy C., Bruening, Ronald L., Huszthy, Peter, Lamb, John D., Bradshaw, Jerald S., Christensen, James J. |
| Zdroj: |
Journal of Inclusion Phenomena and Macrocyclic Chemistry; December 1987, Vol. 5 Issue: 6 p739-745, 7p |
| Abstrakt: |
The macrocycle-mediated fluxes of several alkali metal cations have been determined in a H2O-CH2Cl2-H2O liquid membrane system. Water-insoluble proton-ionizable macrocycles of the pyridono type were used. The proton-ionizable feature allows the coupling of cation transport to reverse H+ transport. This feature offers promise for the effective separation and/or concentration of alkali metal ions with the metal transport being driven by a pH gradient. A counter anion in the source phase is not co-transported. The desired separation of a particular metal ion involves its selective complexation with the macrocycle, subsequent extraction from the aqueous phase to the organic phase, and exchange for H+ at the organic phase-receiving phase interface. Factors affecting transport which were studied include ring size, source phase pH, and receiving phase pH. Lithium was transported at a rate higher than that of the other alkali metals in both single and competitive systems using a 15-crown-5 pyridono carrier. |
| Databáze: |
Supplemental Index |
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