Electrochemical behavior of uranyl in anhydrous polar organic media
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Adam G. Burn
Abstract
Weak complexes between pentavalent and hexavalent actinyl cations have been reported to exist in acidic, non-complexing high ionic strength aqueous media. Such “cation-cation complexes” were first identified in the context of actinide-actinide redox reactions in acidic aqueous media relevant to solvent extraction-based separation systems, hence their characterization is of potential interest for advanced nuclear fuel reprocessing. This chemistry could be relevant to efforts to develop advanced actinide separations based on the upper oxidation states of americium, which are of current interest. In the present study, the chemical behavior of pentavalent uranyl was examined in non-aqueous, aprotic polar organic solvents (propylene carbonate and acetonitrile) to determine whether UO2+ cations generated at the reducing working electrode surface would interact with the UO22+ cations in the bulk phase to form cation-cation complexes in such media. In magnesium perchlorate media, the electrolyte adsorbed onto the working electrode surface and interfered with the uranyl reduction/diffusion process through an ECE (electron transfer/chemical reaction/electron transfer) mechanism. In parallel studies of uranyl redox behavior in tetrabutylammonium hexafluorophosphate solutions, an EC (electron transfer/chemical reaction) mechanism was observed in the cyclic voltammograms. Ultimately, no conclusive electrochemical evidence demonstrated uranyl cation-cation interactions in the non-aqueous, aprotic polar organic solvent solutions, though the results reported do not completely rule out the presence of UO2+·UO22+ complexes.
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©2017 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Electrochemical behavior of uranyl in anhydrous polar organic media
- Electrochemical mechanism of uranium mononitride dissolution in aqueous solutions of nitric acid
- Two novel thorium organic frameworks constructed by bi- and tritopic ligands
- Complexation of vanadium with amidoxime and carboxyl groups: uncovering the competitive role of vanadium in uranium extraction from seawater
- Impact of Cesium decontamination on performances of high activity sample analysis
- Studies on 99Mo–99mTc adsorption and elution behaviors using the inorganic sorbent ceric tungstate and conventional organic resins
- Determination of impurity distributions in ingots of solar grade silicon by neutron activation analysis
- Evaluation of gamma radiation response of electrolyte, MKP and MKT capacitors in various frequencies
- Optimization of operational conditions in continuous electrodeionization method for maximizing Strontium and Cesium removal from aqueous solutions using artificial neural network
Articles in the same Issue
- Frontmatter
- Electrochemical behavior of uranyl in anhydrous polar organic media
- Electrochemical mechanism of uranium mononitride dissolution in aqueous solutions of nitric acid
- Two novel thorium organic frameworks constructed by bi- and tritopic ligands
- Complexation of vanadium with amidoxime and carboxyl groups: uncovering the competitive role of vanadium in uranium extraction from seawater
- Impact of Cesium decontamination on performances of high activity sample analysis
- Studies on 99Mo–99mTc adsorption and elution behaviors using the inorganic sorbent ceric tungstate and conventional organic resins
- Determination of impurity distributions in ingots of solar grade silicon by neutron activation analysis
- Evaluation of gamma radiation response of electrolyte, MKP and MKT capacitors in various frequencies
- Optimization of operational conditions in continuous electrodeionization method for maximizing Strontium and Cesium removal from aqueous solutions using artificial neural network
