SELECTIVE AND EFFICIENT TRANSPORT OF HG(II) THROUGH BULK LIQUID MEMBRANE USING METHYL RED AS CARRIER

Methyl red was used as an excellent carrier for the uphill transport o f Hg(II) through bulb liquid membrane. By using iodide as a metal acce ptor and in the presence of sulfuric acid in receiving phase the amoun t of mercury transport across the bulb liquid membrane was about 90% a fter 180 min. By replacement of the above receiving phase with 0.45 M HCl, a simpler and more reproducible system was obtained. Oleic acid w as used to overcome a minor leaching of the carrier into the aqueous p hase at high acid concentration. This system was optimized with a simp lex optimization program. Under optimum conditions, the amount of Hg(l l) transport across the liquid membrane is about 80% after 150 min. Th e carrier can selectively and efficiently transport Hg2+ ion from aque ous solution containing other cations such as Cd2+, Zn2+, Cu2+, Mg2+, Ca2+ Ag+, Ni2+, Al3+, Na+, Pb2+, Fe3+ and Pd2+. (C) 1998 Elsevier Scie nce B.V.