Remediation strategies based on clay mineral and organoclay derivatives for the adsorption of pharmaceuticals products
Tiago De Oliveira, Régis Guegan, Mohammed Boussafir
Institut des Sciences de la Terre d’Orléans, UMR 7327, CNRS-Université d’Orléans, 1A Rue de la Férollerie, 45071 Orléans Cedex 2, France
Adsorption represents an easy and simple way to remove both organic and inorganic pollutants in water. Clay minerals are well known for their outstanding adsorption properties for numerous products. The chemical modification of its surface through the intercalation of surfactants for the preparation of organoclays considerably improves the adsorption properties, in particular for hydrophobic organic compounds such as pharmaceutical products (PPs), non-biodegraded substances, which are more and more commonly found in sewage and surface water (Ternes, 1998 ; Thiebault, 2015).
In the present contribution, the adsorption PPs onto clay mineral and organoclay derivatives prepared with different surfactants (cationic and nonionic) has been studied with a particular understanding of the interactional mechanisms of PP with the adsorbents. The experimental data obtained by a set of complementary techniques (X-ray diffraction, infrared spectroscopy, ultraviolet-visible spectroscopy, gas chromatography coupled with mass spectroscopy) reveal that organoclays prepared with nonionic surfactants show a versatility for numerous PPs (Guégan, 2015) while the hydrophobic environment generated by the grafting of surfactants with long alkyl-chains particularly enhances the adsorption of the organic compounds.
Keywords: adsorption, composite layered materials, clay mineral, surfactant, organoclay, pharmaceutical product, water
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