Stabilization of supported liquid membranes

Membrane processes provide a relatively new and economically attractive separation technique. One type of membrane processes, i.e. the use of facilitated transport in liquid membranes, is particularly attractive. Compared to other membrane processes, liquid membranes show high selectivities, high diffusion rates through the liquid and provide the possibility of concentrating species by means of a coupled transport process. The work described in this thesis if focussed on supported liquid membranes (SLMs), in which an organic solvent containing a selective carrier is immobilized in the pores of a microfiltration membrane. In spite of their clear advantages are SLMs not used on an industrial scale nowadays. The main reason for this is their lack of stability and subsequently short lifetime. In this thesis, a new method is presented to stabilize SLMs: the precipitation of a polymeric toplayer on the macroporous support by an interfacial polymerization which decreases the loss of the membrane liquid to the adjacent aqueous phases.