Stagnant sandwich liquid membrane

Molinari, R., Argurio, P., PiriHo, F. (2005). Comparison between stagnant sandwich and supported liquid membranes in copper(II) removal from aqueous solutions Flux, stability and model elaboration. J. Membr. Sci., 256, 158-68. 

Molinari, R., Argurio, P., Poeiro, T., Caruso, A. (2006). Stagnant sandwich and supported liquid membrane systems for removal of pharmaceuticals in water. Desalination, 199, 529-31. 

Audunsson [29] reported on a sandwich-type extraction module equipped with liquid membranes, prepared by immersing hydrophobic microporous membranes (e.g. PTFE membranes) in organic solvents for about 15 min. The inert men ranes then act as supports for the immobilized solvent. When an aqueous sample passes by the membrane, non-ionic components in the sample are extracted into the hydrophobic liquid film and transferred into an appropriate acceptor solution on the other side of the membrane. When the acceptor remains stagnant while the sample flows continuous ) for a defined period, a preconcentration is effected in the acceptor solution, which is subsequently transferred to the detector. The procedure is equivalent to extraction and back-extraction in a single step. More details on such a system used for sample cleanup in gas-liquid chromatography is presented in Sec. 3.7. 

Molinari R, Argurio P and Poerio T (2009c), Flux enhancement of stagnant sandwich compared to supported liquid membrane systems in the removal of Gemfibrozil from waters ,/ Membrane Sci, 340,26-34. 

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