Interactions of Dioxouranium(VI) with Polyamines in Aqueous Solution

Abstract

The interaction of the dioxouranium(VI) ion with five low molecular weight polyamines (ethylenediamine,\ud putrescine, cadaverine, spermidine, and spermine) and with poly(allyl)amine (15 kDa) was studied\ud potentiometrically (ISE-H+ glass electrode) at T ) 298.15 K. Investigations were carried out in NaNO3\ud ionic medium, at I ) 0.1 mol ·L-1 (and 0.5 mol ·L-1 for poly(allyl)amine only), in the pH range 3.5 to 5.5,\ud before the formation of uranyl insoluble species. The results gave evidence for the formation of two species,\ud namely, UO2L2+ and UO2L(OH)+ for the diamine systems (ethylenediamine, putrescine, cadaverine), UO2L2+\ud and UO2LH3+ for spermidine, and UO2LH3+ and UO2LH2\ud 4+ for spermine. In the system\ud UO2-poly(allyl)amine, four species, namely, UO2L2+, UO2LH3+, UO2LH2\ud 4+, and UO2L(OH)+, are formed.\ud Speciation profiles of the different systems and the sequestration capability of amines at various pH values\ud are discussed. Some empirical relationships regarding the formation constants of complex species are also\ud reported

Polymer-Supported Primary Amines for the Recovery of Uranium from Seawater

“…The approach taken in this first phase of our research was to study polymer-supported amines as sorbents for uranium from seawater. Polyamines are reported to have good affinity for uranium from neutral and acidic solutions, − as well as seawater conditions. , High complexation constants of linear polyamine with the uranyl cation have also been reported from aqueous carbonate-free solutions, , due perhaps to coordination of the uranyl cation by nitrogen-containing ligands along its equatorial plane …”

Trace Level Uranyl Complexation with Phenylphosphonic Acid in Aqueous Solution: Direct Speciation by High Resolution Mass Spectrometry

“…Regarding organic complexes of uranyl, structural information has often been gained by means of X-ray Absorption Spectroscopy , and Attenuated Total Reflectance Fourier Transform Infrared spectroscopy, , which are powerful speciation techniques (because of their ability to probe the local structure around an atom and the chemical bonds, respectively) but are not applicable to poorly concentrated uranyl solutions. Thermodynamic stability data and constants for the uranyl-organic ligand systems have been obtained commonly by using potentiometry, − UV–vis spectrophotometry, and Time-Resolved laser-induced Fluorescence spectroscopy (TRLFS). Among all the techniques mentioned above, TRLFS is the only one that is applicable to solutions with very low uranyl concentrations relevant to the environment.…”