In a liquid membrane, the type of diluents for the selected extractant plays an important role in membrane stability and separation efficiency. High Pd(II) extraction and stripping of 96% and 91%, respectively, were observed by HFSLM under a feed pH 2, 5% (v/v) LIX84-I dissolved in kerosene and a mixture of 0.8M NH<inf>2</inf>CSNH<inf>2</inf> with 1M HCl as a stripping solution. The highest stability was attained at 350min by using hexane as a diluent. Finally, the calculated activation energy (E<inf>a</inf>) of 30 kJ/mol implied that the separation of Pd(II) was controlled by the diffusion and chemical reaction.
