Institut de Chimie Moléculaire et des Matériaux d'Orsay

Mixed hybridization systems : Towards the "after C60"

Axis 1 — Calixarene-based materials for decontamination and recovery of strategic metals

Associate researcher and collaborator : Ekaterina Shilova (AJELIS), Pascal Viel (LICSEN, CEA)

Calixarenes are well known to form inclusion complexes with a vast array of organic/inorganic hosts (metallic/organic ions, small neutral molecules, etc…).

Within this frame, they are commonly used for example for the recovery of radioactive cesium from nuclear effluents, mostly using liquid/liquid extraction processes.

Although efficient, these liquid-liquid extraction processes are suffering from significant drawbacks, such as i) the use of large amounts of organic solvents, ii) the production of secondary effluents, and iii) the relative complexity of the associated workup.

In strong collaboration with the CEA (French Alternative Energies and Atomic Energy Commission), we are developing for some years new solid-liquid extraction processes. The ion-selective “molecular traps” (calixarenes, crown ethers, etc…) are grafted on the surface of solid, electrically conducting surfaces (such as carbon felts). This makes possible the direct and selective transfer of the targeted metallic ions from solutions to the solid supports. This considerably eases the processing. Moreover, the electrically conductive substrate allows for the very easy recycling of the adsorbents. This new process is currently on the pilot scale for the extraction of cesium from aqueous wastes.

More recently, these materials were also adapted to the recovery of strategic metals (lanthanides, lithium…).

Based on this new technology, a start-up (the AJELIS company) was launched in 2014.

(A) Cesium-selective calixarene grafted onto the surface of carbon felts

(B) Reversible adsorption/desorption of the targeted metals from the solid substrates

(C) The corresponding pilot

Last update on 11.13.2019