6IPGP - Institut de Physique du Globe de Paris (IPGP, 1 rue Jussieu, 75238 Paris cedex 05 ; Université Paris Diderot, Bât. Lamarck A case postale 7011, 75205 Paris CEDEX 13 - France)
Abstract : Polyamidoximes (pAMD) are known to have strong affinities for uranyl cations. Grafting pAMD onto the surface of functionalized maghemite nanoparticles (MNP) leads to a nanomaterial with high capacities in the extraction of uranium from wastewaters by magnetic sedimentation. A diamidoxime (dAMD) specifically synthesized for this purpose showed a strong affinity for uranyl: Ka = 105 M-1 as determined by Isothermal
Titration Calorimetry (nano-ITC). The dAMD was grafted onto the surface of MNP and the obtained sorbent (MNP-dAMD) was characterized. The nanohybrids were afterward incubated with different concentrations of uranyl and the solid phase recovered by magnetic separation. This latter was characterized by zeta-potential measurements, X-Ray Photoelectron Spectroscopy (XPS) and X-Ray Fluorescence spectroscopy (XRF), whereas the supernatant was analyzed by Inductively Coupled Plasma coupled to Mass Spectrometry (ICP-MS). All the data fitted the models of
Langmuir, Freundlich and Temkin isotherms very well. These isotherms allowed us to evaluate the efficiency of the adsorption of uranium by MNP-dAMD. The saturation sorption capacity (qmax) was determined. It indicates that MNP-dAMD is able to extract up to 120 mg of uranium per gram of sorbent. Spherical aberration (Cs)- corrected High-Resolution Scanning Transmission Electron Microscopy (HRSTEM) confirmed these results and clearly showed that uranium is confined at the surface of the sorbent. Thus, MNP-dAMD presents a strong potential for the extraction of uranium from wastewaters
https://hal-insu.archives-ouvertes.fr/insu-02526266 Contributor : Eva FareauConnect in order to contact the contributor Submitted on : Thursday, August 6, 2020 - 1:40:56 PM Last modification on : Thursday, April 7, 2022 - 1:58:30 PM Long-term archiving on: : Monday, November 30, 2020 - 3:46:47 PM
Eva Mazarío, Ahmed Helal, Jérémy Stemper, Alvaro Mayoral, Philippe Decorse, et al.. Maghemite nanoparticles bearing di(amidoxime) groups for the extraction of uranium from wastewaters. AIP Advances, American Institute of Physics- AIP Publishing LLC, 2017, 7 (5), pp.056702. ⟨10.1063/1.4973436⟩. ⟨insu-02526266⟩