New insights into the uranium adsorption behavior of mesoporous SBA-15 silicas decorated with alkylphosphine oxide ligands

Abstract

Alkylphosphine oxide functionalized mesoporous silicas were prepared by co-condensation and further addition reaction with secondary n-propylphosphine oxide and are promising candidates for the preconcentration and adsorption of uranium from acidic aqueous solutions.

Theoretical and experimental studies on uranium(vi) adsorption using phosphine oxide-coated magnetic nanoadsorbent

“…3(a) shows that the adsorption capacity of Fe 3 O 4 @Cyanex-923 increases with the pH increase to reach its utmost value at pH ∼5 and then levels off. This behavior is similar to that reported for silica coated with alkylphosphine oxides, 32 as higher uranium( vi ) adsorption was attained at pH 5. At low pH values, the predominant uranium species is UO 2 2+ which competes with the abundant H + and H 3 O + ions for the binding sites on the Fe 3 O 4 @Cyanex-923 surface, 46 and consequently the adsorption is unfavorable at low pH.…”

“…29,30 In particular, trialkylphosphine oxides are cost-effective neutral extractant with demonstrated high extraction capacity and high stability in strong acidic media, which makes them are excellent ligands to functionalize various adsorbents for uranium capture. 31,32 Cyanex-923 is a promising phosphine oxide extractant which revealed high radiation stability, good hydrolysis resistance, poor water solubility, and non-corrosive nature; 33,34 thus, it could be a potential candidate to be impregnated onto the Fe 3 O 4 surface for the efficient uranium adsorption.…”

Ion-Imprinted Mesoporous Silica for Selective Removal of Uranium from Highly Acidic and Radioactive Effluent

“…To date, a variety of sorbents have been developed for exaction of uranium from highly acidic and/or radioactive medium, such as synthetic resins, − mesoporous silica − and covalent organic framework . For example, Subramanian et al .…”

Solvation of the Ca2UO2(CO3)3 Complex in Seawater from Classical Molecular Dynamics

“…In fact, a recent marine testing of a polymer fiber sorbent after 56-day seawater exposure showed that a significant amount of Na + ions was retained in the sorbent. 32 Thus, it is of great importance to illuminate the impact of salt on the solvation of Ca 2 UO 2 (CO 3 ) 3 in seawater. The present work seeks to simulate Ca 2 UO 2 (CO 3 ) 3 in seawater via classical MD simulation, by including Na + and Cl − ions explicitly in our model.…”