Lithium and potassium ions transfer processes across the ities in the presence of crown ethers

الملخص EN

The electrolytic cell with the electrolyte dropping electrode comprised Ag / AgCl as working electrode, Ag / AgCl reference electrode and platinum wire counter electrode.

This cell evaluated by the determination of the thermodynamics data for lithium and potassium ions transfer across a liquid-liquid interface in the presence of the crown ethers.

In the present system we intend to demonstrate the use of a simple threeelectrode assembly with electrolyte dropping electrode for the study of the interfacial ion transfer.

In particular, we focused on the transfer of lithium and potassium ions from water to 1, 2- dichloroethane (1, 2-DCE) facilitated by complex formation with benzo-15- crown -5 (B15C5), 18-crown -6 (18C6), dibenzo-18 – crown-6 (B218C6) and dicyclohexyl-18- crown -6 (Cy2 18C6). Extensive thermodynamics data, suggest that the standard Gibbs energies of transfer of lithium and potassium ions from water to 1, 2-DCE and stability constant of crown ether complexes depends on the relative cation and ligand cavity size, the number and special arrangements of the ligand binding sites and the substitution on the macrocyclic ring.