Solvent Extraction and Transport of Rare Earth Metal Ions Using 5.11.17.23-Tetra-tert-butyl-25,27-bis (diethylcarbomoylmethoxy)-26,28-dihydroxy Calix[4]arene

Abstract

The solvent extraction of rare earth metal ions from nitrate solutions by 5.11.17.23-tetra-tert-butyl-25,27-bis(diethylcarbamoylmethoxy)-26,28-dihydroxycalix[4]arene (L) in 1,2-dichloroethane has been investigated. The alalysis of the extraction equilibrium obtained from a mixture of La3+, Eu3+, Er3+ and Y3+ revealed that the extracted species have a 1:1 metal/ligand ratio. The intra-group separation efficiencies of the ligand have been evaluated in a competitive extraction and transport of 11 rare earth metal ions (La3+, pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Dy3+, Ho3+, Yb3+ and Y3+). The transport experiment has been performed through a supported liguid membrane containing the ligand in o-nitrophenyl hexyl ether (NPHE). The distribution ratio and the flux of the ions generally increases as the atomic radii decrease.

Keywords

• calix[4]arene
• extraction
• transport
• rare earth
• metal ions