C. Hill et al., NUCLEAR WASTE TREATMENT BY MEANS OF SUPPORTED LIQUID MEMBRANES CONTAINING CALIX-CROWN COMPOUNDS, Journal of inclusion phenomena and molecular recognition in chemistry, 19(1-4), 1994, pp. 399-408
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 t
he SLM stability. Whereas classical crown ethers such as the widely us
ed 21C7 derivatives were revealed to be poorly efficient and poorly st
able in SLMs, crown-6-calix[4]arene compounds in the so-called 1,3-alt
ernate configuration led to very stable (over 50 days), highly selecti
ve (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 an
d introducing hydrophobic substituents in the frame of the calixarenes
.