Stability of the emulsion (W/O): Application to the extraction of a Dawson type heteropolyanion complex in aqueous solution

Dawson type heteropolyanions form complexes with transition metals. These mixed complexes possess some remarkable electrocatalytic properties. Being soluble in aqueous and organic phases, they are used in homogeneous catalysis. In the setting of the recuperation and the regeneration of these complexes, the extraction of a mixed heteropolyanion (alpha 2P2W12Mo5O61Fe)(7)- is the subject of this work. This extraction was carried out by emulsified liquid membrane using (SPAN80) as surfactant and (TIBA) as extractant. Sulfuric acid was used as the internal phase. The stability of the emulsion was studied according to different parameters and the extracting efficiency in optimal conditions was found to be 70%. (C) 2007 Elsevier B.V All rights reserved.