Efficient and Selective Transport of Silver(I) Cation Across a Bulk Dichloromethane Membrane Using 1,13-Bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane as a Carrier

G H Rounaghi,A Ghaemi

doi:10.1155/2012/941956

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 3×10-4M 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.

Highlights

Silver is used widely in the production of coins, jewellery, tableware and alloys, and in the manufacture of electrical apparatus, mirrors and chemicals for photographic processes
The organic solvent which should be immiscible with water and non-volatile must have a suitable polarity related to an optimal value of the association constant of the complex
We have examined the influence of some organic solvents as membrane phase

Summary

Introduction

Silver is used widely in the production of coins, jewellery, tableware and alloys, and in the manufacture of electrical apparatus, mirrors and chemicals for photographic processes. We tested the competitive transport of Co2+, Fe3+, Cd2+, Cu2+, Zn2+, Ag+ and Pb2+ metal cations from an aqueous source phase into an aqueous receiving phase through NB, CHCl3, DCM and 1,2-DCE organic solvents as liquid membranes containing kryptofix 5 ligand at ambient temperature [18].

Results

Conclusion