Uranium Sorption on Various Forms of Titanium Dioxide – Influence of Surface Area, Surface Charge, and Impurities

Abstract

Titanium dioxide (TiO(2)) has often served as a model substrate for experimental sorption studies of environmental contaminants. However, various forms of Ti-oxide have been used, and the different sorption properties of these materials have not been thoroughly studied. We investigated uranium sorption on some thoroughly characterized TiO(2) surfaces with particular attention to the influence of surface area, surface charge, and impurities. The sorption of U(VI) differed significantly between samples. Aggressive pretreatment of one material to remove impurities significantly altered the isoelectric point, determined by an electroacoustic method, but did not significantly impact U sorption. Differences in sorption properties between the various TiO(2) materials were related to the crystallographic form, morphology, surface area, and grain size, rather than to surface impurities or surface charge. In-situ attenuated total reflection Fourier-transform infrared (ATR FT-IR) spectroscopic studies showed that the spectra of the surface species of the TiO(2) samples are not significantly different, suggesting the formation of similar surface complexes. The data provide insights into the effect of different source materials and surface properties on radionuclide sorption.

Sorption of U(VI) at the TiO2–water interface: An in situ vibrational spectroscopic study

“…In the pH range from 3 to 7, the spectroscopic data indicate increasing U(VI) uptake by TiO 2 . This is in good agreement to previous spectroscopic and macroscopic data (Guo et al, 2004;Pandey, 2006;Lefèvre et al, 2008;Comarmond et al, 2011). Moreover, the isoelectric point (IEP) of sample S6 was determined to be at pH 6 (cf.…”

“…The solid was recovered by centrifugation and dried at 80°C, and ball-milled back to powder form. A more detailed characterization of the washed samples is given in (Comarmond et al, 2011).…”

Synthesis of Fe3O4@TiO2 core–shell magnetic composites for highly efficient sorption of uranium (VI)

“…At the same time, it is also of potential environmental relevance due to its high adsorptive capacity for uranium (VI) [27][28][29][30].…”

Synthesis of amidoximated polyacrylonitrile fibers and its application for sorption of aqueous uranyl ions under continuous flow

“…To improve the sorption capacity of sorbents, many attempts have been made for chemical modification of sorbent surfaces using functional groups such as amidoxime [3,14,15], imidazole [16], and metal oxides [4,17,18], which possess chelating abilities toward U(VI) ions. As commonly used sorbents are in powder form, their utilization as a filter material is not convenient due to the difficulty in the isolation of the solid from the solution medium following the sorption stage.…”