| Autor: |
Yang H; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China., Huang T; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China., Chen Y; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China., Wang YH; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China., Jin YD; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China., Chen XC; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China., Xia CQ; College of Chemistry, Sichuan University, Chengdu 610064, P. R. China. |
| Abstrakt: |
A new type of phenanthroline carboxamide(DAPhen)-phosphate ester ligand ( L1 / L2 ) was synthesized for the selective separation of U(VI) over Th(IV). Liquid-liquid extraction experiments showed that the introduction of phosphate ester could increase the extraction ability of ligands for U(VI), especially L2 , which showed high selectivity for the separation of U(VI) over Th(IV). The slope analysis indicated that L1 could form 1:1 and 1:2 complexes with U(VI) and 1:1 complexes with Th(IV). NMR titration revealed that the DAPhen unit of ligands combined with one U(VI) to form 1:1 complexes, and then the phosphate ester unit of the 1:1 complexes further combined with another U(VI) to form 1:2 complexes. Ligands provide only the DAPhen unit to Th(IV) to form 1:1 complexes. The crystal structures found 1:2 complexes of L1 and U(VI), 1:1 complexes of L2 and U(VI), and 1:1 complexes of L1 and Th(IV). The larger stability constant (log β) of the 1:1 complexes of L2 with U(VI) than that of the 1:1 complexes of L1 with U(VI) showed that the binding ability of U(VI) with the DAPhen unit of L2 is stronger than that of U(VI) with the DAPhen unit of L1 . This study provides new ideas for designing extractants with excellent properties. |
