Tetraazamacrocyclic ion exchangers tethered to Merrifield peptide resin (DTDM, TTTM) were prepared and the ion exchange capacity of these was characterized. The isotope separation of lithium was determined using breakthrough method of column chromatography. The isotope separation coefficient was strongly dependent on the ligand structure by Glueckauf's theory. We found that the isotope separation coefficients were increased as the values of distribution coefficients were increased. In this experiment the lighter isotope, 6 Li was enriched in the resin phase, while the heavier isotope, 7 Li in the solution phase. The ion radius of lighter isotope, 6 Li was shorter than the heavier isotope, Li. The hydration number of lithium ion with the same charge became small as mass number was decreased. Because 6 Li was more strongly retained in the resin than 7 Li, the isotopes of lithium were separated with subsequent enrichment in the resin phase.

Tetraazamacrocyclic ion-exchangers, 1,4,8,11-tetraazacyclotetradecane bonded Merrifield peptide resin(TDM), 1,4,8,12-tetraazacyclopentadecane bonded Merrifield peptide resin(TPM) were prepared, and the ion-exchange capacity of these TDM and TPM were characterized. The distribution coefficients in various conc. of NH4Cl for magnesium with ion exchangers were determined by using the batch method. We found the isotope separation factors on new prepared tetraazamacrocyclic ion-exchangers bonded Merrifield peptide resin(TDM, TPM). The isotope separation of magnesium was determined by using of breakthrough method of column chromatography.