NUCLEAR WASTE TREATMENT BY MEANS OF SUPPORTED LIQUID MEMBRANES CONTAINING CALIX-CROWN COMPOUNDS

Permeability variation with repeated caesium transport experiments has been chosen to measure the leaching of the supported liquid membrane by the contacting aqueous solutions. This allowed us to characterize the SLM stability. Whereas classical crown ethers such as the widely used 21C7 derivatives were revealed to be poorly efficient and poorly stable in SLMs, crown-6-calix[4]arene compounds in the so-called 1,3-alternate configuration led to very stable (over 50 days), highly selective (concentration factor > 100) and efficient (decontamination factor = 20) SLMs, for the removal of caesium from high salinity and acidity media. These results were achieved by using proper organic diluents and introducing hydrophobic substituents in the frame of the calixarenes.