DI-UMONS : Dépôt institutionnel de l’université de Mons

Recherche transversale
Rechercher
(titres de publication, de périodique et noms de colloque inclus)
2020-01-16 - Article/Dans un journal avec peer-review - Anglais - 8 page(s)

Heymans Nicolas , Bourrelly S., Normand Périne , Bloch E., Mkhadder H., Cooper L., Gorman M., Bouzidi I., Guillou N., De Weireld Guy , Devic T., "Small Pore Gallates MOFs for Environmental Applications: Sorption Behaviors and Structural Elucidation of Their High Affinity for CO2" in Journal of Physical Chemistry C, 124, 5, 3188-3195, https://doi.org/10.1021/acs.jpcc.9b11535

  • Edition : American Chemical Society (DC)
  • Codes CREF : Chimie des surfaces et des interfaces (DI1327), Traitement des effluents gazeux (DI3843), Environnement et pollution (DI3840), Technologie de l'environnement, contrôle de la pollution (DI3841), Thermodynamique chimique (DI132C)
  • Unités de recherche UMONS : Thermodynamique, Physique mathématique (F506)
  • Instituts UMONS : Institut de Recherche en Energétique (Energie)
Texte intégral :

Abstract(s) :

(Anglais) The ability of two small pore Metal Organic Frameworks (MOFs) to capture CO2 was investigated by a combination of gas sorption measurements, X-ray powder diffraction (XRPD) analysis, microcalorimetry experiments and Ideal Adsorbed Solution Theory (IAST) calculations. The title solids, formulated Mg(H2gal) and Fe(Hgal) (H4gal = gallic acid) are made of a naturally occurring ligand, and were both prepared on the multigram scale under mild conditions. They both present very similar structures, with identical channels of ca 3.5 Å diameter, but present different amounts of acidic protons on the surface of the pores. These compounds were found to be extremely hydrophilic, and exhibit a moderate stability towards water. Whilst their ability to adsorb CH4 and N2 is very limited, they both adsorb significant amounts of CO2 even at low pressure (3 and 5 mmol g-1 at 1 bar and 303 K for the Fe and Mg derivatives respectively). As a consequence, these compounds present high CO2/N2 and CO2/CH4 selectivities together with good working capacities, making them of interest for the capture of CO2 from flue gas or for landfill gas upgrading in pressure swing adsorption or vacuum swing adsorption processes. Finally, the analysis of the Mg derivative by X-Ray Diffraction (XRD) and adsorption microcalorimetry revealed that its high affinity for CO2 relies on a strong and specific site of adsorption involving double hydrogen bonds between the CO2 molecules and the acidic protons of the framework.