Selective liquid membrane transport of Pd(II) as PdCl42- ion using potassium-dicyclohexyl-18-crown-6 as carrier

Potassium-dicyclohexyl-18-crown-6 complex was used as a highly efficient ca rrier for the trans port of palladium as PdCl42- complex anion through a ch loroform bulk liquid membrane. In the presence of thiocyanate ion as a suit able stripping agent in the receiving phase, the amount of palladium transp orted across the liquid membrane after 2.5 h is 99.2 +/- 1.1%. The selectiv ity of Pd2+ transport from aqueous solutions containing other Mn+ cations s uch as Mg2+, Ca2+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+, Cd2+, Hg2+, and Fe3 was investigated. In the presence of EDTA as a suitable masking agent in t he source phase, none of the cations used interfered with palladium transpo rt, even at a Mn+/Pd2+ molar ratio of 10. (C) 1999 Academic Press.