This study reports the stabilization of supported liquid membranes, through cross-linking the liquid membrane phase by using gamma-radiation, and the performance of the resulting membranes under Membrane Aromatic Recovery System (MARS) operating conditions. The membranes were prepared by impregnating polypropylene glycol (PPG) into the pores of microporous flat sheet membranes [polyvinylidene fluoride (PVDF) or polypropylene (PP)l and subsequently exposing them to gamma-radiation. The membranes prepared exhibited operational stability when investigated under MARS operating conditions for more than 1 month. The PP (0.05 mm) membrane provided the best combination of high phenol mass transfer rates and low water flux for the MARS process among the membranes tested in this study. The phenol mass transfer rate through this membrane (27 x10(-7) m s(-1)) was 18 times higher than that of silicone rubber tubing (1.5 x 10(-7) in s(-1)). This study also reports the effect of radiation dose on the mass transfer rates and on the membrane support itself.