Abstract

1,13-Bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane (Kryptofix 5) was used as a highly efficient carrier for the transport of silver(I) cation through a dichloromethane (DCM) bulk liquid membrane. In order to achieve the highest transport efficiency of Ag+ cation across the bulk liquid membrane system, the influence of different parameters was studied. These include: the nature of various organic solvents as liquid membrane phase, concentration of the carrier in the membrane phase, concentration of picric acid as counter anion in the source phase, type of various stripping agents in the receiving phase, concentration of thiosulfate anion (S2O32-) as a suitable stripping agent, pH of the source and receiving phases, volume of the receiving phase and equilibrium time of transport which were optimized. In the optimum procedure conditions, the transport of a 3×10-4 M solution of silver(I) cation was observed (88.03 ± 0.82%) after 4 hours. The selectivity of Ag+ transport from aqueous solutions containing equimolar concentration of other metal cations such as Pb2+, Co2+, Zn2+, Cd2+, Cu2+ and Fe2+ was also investigated.