A microwave synthesis of porous iron and chromium oxides was performed from aqueous solutions of metal nitrates with urea. The resulting oxides were characterized by X-ray phase analysis and scanning electron microscopy. Both oxides were found to have the same rutile crystal structure (R̅3c). The specific surface area was measured using the Brunauer-Emmett-Teller (BET) method. The specific surface areas were 45 and 142 m2/g for chromium oxide and iron oxide, respectively. The study of the dependence of the adsorption of the pesticide glyphosate on the real surface area of chromium and iron oxides as soil components will allow the determination of the effect of process parameters on the sorption properties of individual metal oxides and soils as a whole. A model for the interaction of adsorbate molecules with the surface of sorption materials will be developed from the understanding of this process. Differences in the adsorption of glyphosate on the metal oxide surface at different pH values are explained by the presence of two contributions to the interaction of the glyphosate molecule with the oxide surface - coordination and electrostatic. The combined influence of the metal oxide surface structure and the way glyphosate exists in solutions at different pH and temperature has been demonstrated by different types of adsorption isotherms, by dependence on the donor strength of the adsorbing eluent and by calculating the thermodynamic parameters of the process.
Original languageEnglish
Article number136114
Number of pages27
JournalColloids and Surfaces A: Physicochemical and Engineering Aspects
Volume709
Issue number2
DOIs
StatePublished - 20 Mar 2025

    Research areas

  • Clay minerals, Sorption, Sorption thermodynamics parameters, Specific surface area, Surface complexes

ID: 127403276