1Department of Chemistry, University of Zanjan, P.O. Box 313-45195, Zanjan, I.R. IRAN
2Laboratory of Mineral and Analytical Chemistry, CNRS, No. 7512, ECPM, University of Louis Pasteur, Strasbourg, FRANCE
3Group of Molecular Inorganic Chemistry, CNRS, No. 7513, University of Louis Pasteur, Strasbourg, FRANCE
The solvent extraction of rare earth metal ions from nitrate solutions by 18.104.22.168-tetra-tert-butyl-25,27-bis(diethylcarbamoylmethoxy)-26,28-dihydroxycalixarene (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.