Selective separation of gold(III) ions from acidic aqueous Solutions. using MIBK Lis carrier and LK-80 as emulsifier. has been investigated. The extraction results from model solution containing Au3+, Pd2+, Pt4+, Cu2+ and Fe3+. showed that only the Au3+ ions transported across the liquid membrane and nearly all of other ions remained in the external Solution without change in their concentration. Mathematical modeling of the system shows a good compatibility with experimental results for gold(III) ions transport. For other ions. the partition coefficient of the ions and membrane phase is nearly equal to zero. Then these ions form complexes with the carrier without stripping and remain unchanged in the system. (c) 2006 Elsevier B.V. All rights reserved.