EXTRACTION OF PALLADIUM BY LIQUID SURFACTANT MEMBRANES USING NEW SURFACTANTS

Using novel synthetic surfactants, the extraction of palladium(II) by liquid surfactant membranes (LSM) containing didodecylmonothiophosphoric acid as a carrier was conducted in a stirred cell. The role of the surfactants on the extraction behavior of palladium by the LSMs was systematically studied. It was found that the stability of the emulsion and the permeation rate of palladium are strongly influenced by the surfactants used. The effects of the surfactant, extractant, internal hydrogen ion and thiourea (stripping reagent) concentrations on the palladium extraction are discussed. The presence of thiourea in the internal aqueous phase is a key factor in palladium extraction with an LSM. Extraction of more than 95% could be attained in a few minutes under optimum surfactant and carrier concentrations.