Benzo-18-Crown-6 (B18C6) was used as a highly selective and efficient carrier for the transport of Pb2+cation through a dichloromethane bulk liquid membrane (BLM). In order to achieve the highest transport efficiency of Pb2+cation across the bulk liquid membrane system, the influence of different parameters on Pb2+cation transport was investigated. This includes the nature of various organic solvents as liquid membrane phase, concentration of B18C6 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 ion as a suitable stripping agent in the receiving phase, pH of the source and receiving phases and equilibrium time of transport which were optimized. In the optimum procedure conditions, the transport of a 1×10-4 M solution of Pb2+cation was observed (88.0 ± 0.7%) after 4 hours. The selectivity and efficiency of Pb2+cation transported from aqueous solutions containing equimolar mixtures of Cr3+, Co2+, Cu2+, Zn2+, Cd2+ and Ag+ metal cations were investigated.

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