Selective transport of silver ion through a supported liquid membrane using hexathia-18-crown-6 as carrier

A facile supported liquid membrane (SLM) system for the selective and effic ient transport of silver ion is introduced. The SLM used is a thin porous p olyvinyldifluoride membrane impregnated with hexathia-18-crown-6 (HT18C6) d issolved in nitrophenyloctyl ether. HT18C6 acts as a specific carrier for t he uphill transport of Ag+ ion as its picrate ion paired complex through th e SLM. In the presence of thiosulfate ion as a suitable stripping agent in the ship solution, transport of silver occurs almost quantitatively after 4 h. The selectivity and efficiency of silver transport from aqueous solutio ns containing other Mn+ cations such as Mg2+, Ca2+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+, Cd2+, Hg2+, Fe3+ and Cr3+ ions were investigated.