Analytical Sciences


Abstract − Analytical Sciences, 32(12), 1367 (2016).

Synergistic Ion-pair Extraction of Strontium Ion with Tri-n-octylphosphine Oxide and Dicyclohexano-18-crown-6
Mami ONIZAKI,* Kotaro MORITA,* and Naoki HIRAYAMA*,**
*Department of Chemistry, Faculty of Science, Toho University, 2-2-1 Miyama, Funabashi 274-8510, Japan
**Research Center for Materials with Integrated Properties, Toho University, 2-2-1 Miyama, Funabashi 274-8510, Japan
The co-use of two neutral ligands, tri-n-octylphosphine oxide (TOPO) and dicyclohexano-18-crown-6 (DC18C6), for ion-pair extraction of divalent strontium (Sr2+) with bis(trifluoromethanesulfonyl)imide anion (Tf2N) showed unique synergistic effect. The extracted species in use of a single ligand is Sr(TOPO)32+·2Tf2N or Sr(DC18C6)2+·2Tf2N, whereas the co-use resulted in extraction enhancement based on additional formation of Sr(DC18C6)(TOPO)2+·2Tf2N and Sr(DC18C6)(TOPO)22+·2Tf2N.