Separation study of cadmium through an emulsion liquid membrane

A study of the transport of Cd(2+) ions through a tri-ndashoctylamine(TOA)-sorbital monooleate (Span 80)-oxylene liquid membrane has been performed with varying concentrations of HCl, KI, TOA, Span 80 and NaOH in the feed, membrane and stripping solutions. Maximum transport was observed at 0.01 M KI, 0.025 M HCl, 0.015 M TOA, 3% (w/v) Span 80 and 0.025 M NaOH. With this system, cadmium could be completely separated from Zn(2+), Fe(2+), Co(2+), Ni(2+), Cr(3+) and Mn(2+). The transport mechanism of this metal ions through the membrane has been discussed.