Efficient removal of perfluorinated contaminants
Ljubljana, August 6, 2020 - Perfluorinated compounds (PFCs) have found wide applications but have adverse effects on health and the environment, and there is a need to selectively recover them from process and surface waters.
In a Communication, published in Angewandte Chemie, the researchers from Leuven, Montpellier, Marseille and Ljubljana, show that a microporous zeolite Beta, in its all‐silica form, shows outstanding capacity and affinity for the uptake of PFCs such as perfluorooctanoic acid and perfluorooctanesulfonic acid, even in the presence of other organic compounds. Through solid-state NMR measurements,
Andraž Krajnc and Gregor Mali from the Department of Inorganic Chemistry and Technology of the National Institute of Chemistry elucidated the way in which the molecules of a representative of PFCs, perfluorinated octanioc acid (PFOA), were adsorbed into the zeolite Beta. They showed that PFOA molecules were positioned in the straight a‐ and b‐channels of the zeolite, with the hydrophobic chains in the channels and the carboxylic heads, forming hydrogen bonded pairs, in the intersections. This resulted in a very favorable adsorption enthalpy. Additionally, the helical conformation of the perfluorinated chains made a very tight packing at maximal capacity sterically possible. This explained the exceptionally high affinity and selectivity of all‐silica zeolite Beta for PFOA and similar perfluorinated compounds.
The above described properties position this unusual zeolite as the lead candidate for combating the PFCs pollution.
For further information please contact: gregor.mali[at]ki.si