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Extraction of tetra-oxo anions into a hydrophobic, ionic liquid-based solvent without concomitant ion exchange / Dominique C. Stepinski in Industrial & engineering chemistry research, Vol. 49 N° 12 (Juin 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 12 (Juin 2010) . - pp. 5863–5868 Titre : Extraction of tetra-oxo anions into a hydrophobic, ionic liquid-based solvent without concomitant ion exchange Type de document : texte imprimé Auteurs : Dominique C. Stepinski, Auteur ; George F. Vandegrift, Auteur ; Ilya A. Shkrob, Auteur Année de publication : 2010 Article en page(s) : pp. 5863–5868 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Ionic  liquids  Tetra-oxo  anions Résumé : Hydrophobic ionic liquids (IL) have the potential to simplify certain separations by serving as both an extraction solvent and an electrolyte for subsequent electrochemical reductions. While IL-based solvents are known to be efficient media for metal ion extraction, separations employing these solvents are frequently complicated by the loss of constituent IL ions to the aqueous phase, resulting in deteriorating performance. In this study, we have examined the extraction of pertechnetate and related tetra-oxo anions from aqueous solutions into IL-based solvents incorporating tetraalkylphosphonium bis[(trifluoromethyl)sulfonyl]imide and a crown ether. In contrast to various previously studied IL-based cation extraction systems, facile anion extraction without significant transfer of the IL ions to the aqueous phase has been observed. In addition, the solvents exhibit high distribution ratios (100−500 for pertechnetate), significant electrical conductivity (>100 μS/cm), and a wide (∼4 V) electrochemical window. The results suggest that these solvents may provide the basis for improved approaches to the extraction and recovery of a variety of anions. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1000345 [article] Extraction of tetra-oxo anions into a hydrophobic, ionic liquid-based solvent without concomitant ion exchange [texte imprimé] / Dominique C. Stepinski, Auteur ; George F. Vandegrift, Auteur ; Ilya A. Shkrob, Auteur . - 2010 . - pp. 5863–5868. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 12 (Juin 2010) . - pp. 5863–5868 Mots-clés : Ionic  liquids  Tetra-oxo  anions Résumé : Hydrophobic ionic liquids (IL) have the potential to simplify certain separations by serving as both an extraction solvent and an electrolyte for subsequent electrochemical reductions. While IL-based solvents are known to be efficient media for metal ion extraction, separations employing these solvents are frequently complicated by the loss of constituent IL ions to the aqueous phase, resulting in deteriorating performance. In this study, we have examined the extraction of pertechnetate and related tetra-oxo anions from aqueous solutions into IL-based solvents incorporating tetraalkylphosphonium bis[(trifluoromethyl)sulfonyl]imide and a crown ether. In contrast to various previously studied IL-based cation extraction systems, facile anion extraction without significant transfer of the IL ions to the aqueous phase has been observed. In addition, the solvents exhibit high distribution ratios (100−500 for pertechnetate), significant electrical conductivity (>100 μS/cm), and a wide (∼4 V) electrochemical window. The results suggest that these solvents may provide the basis for improved approaches to the extraction and recovery of a variety of anions. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie1000345

Surface modified, collapsible controlled pore glass materials for sequestration and immobilization of trivalent metal ions / Ilya A. Shkrob in Industrial & engineering chemistry research, Vol. 50 N° 8 (Avril 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4686–4696 Titre : Surface modified, collapsible controlled pore glass materials for sequestration and immobilization of trivalent metal ions Type de document : texte imprimé Auteurs : Ilya A. Shkrob, Auteur ; Angela R. Tisch, Auteur ; Timothy W. Marin, Auteur Année de publication : 2011 Article en page(s) : pp. 4686–4696 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Chemical  modification  X-ray  absorption  Metal  ions Résumé : We report a one-pot method for sequestration, containment, and immobilization of lanthanide (Ln) ions from dilute aqueous waste streams. The approach is based on the use of collapsible, surface modified controlled pore glass (CPG) nanomaterials. We present several approaches for a single-step chemical modification of 3-propylaminated CPGs that yield highly efficient Ln-extracting materials with distribution coefficients exceeding 10000 mL/g. The resulting Ln complexes were studied using X-ray absorption, magnetic resonance, and time-resolved luminescence spectroscopies. One of these CPG materials involving an imidodi(methanediphosphate) moiety demonstrated high extraction efficacy, significant ionic radius sensitivity, and exceptional tolerance to masking agents, which is conducive to its use for removal of traces of radionuclide ions from aqueous TALSPEAK raffinate (trivalent actinide−lanthanide separation by phosphorus reagent extraction from aqueous complexes process used in processing of spent nuclear fuel). The glass loaded with the extracted metal ions can be calcined and sintered at 1100 °C, yielding fused material that buries Ln ions in the vitreous matrix. This processing temperature is significantly lower than 1700 °C that is required for direct vitrification of lanthanide oxides in high-silica glass. X-ray absorption spectroscopy and acid leaching tests indicate that the immobilized ions are isolated and dispersed in the fused glass matrix. Thus, the method integrates Ln ions into the glass network. The resulting glass can be used for temporary storage or as the source of silica for production of borosilicate waste forms that are used for long-term disposal of high level radioactive waste. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie102494r [article] Surface modified, collapsible controlled pore glass materials for sequestration and immobilization of trivalent metal ions [texte imprimé] / Ilya A. Shkrob, Auteur ; Angela R. Tisch, Auteur ; Timothy W. Marin, Auteur . - 2011 . - pp. 4686–4696. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 8 (Avril 2011) . - pp. 4686–4696 Mots-clés : Chemical  modification  X-ray  absorption  Metal  ions Résumé : We report a one-pot method for sequestration, containment, and immobilization of lanthanide (Ln) ions from dilute aqueous waste streams. The approach is based on the use of collapsible, surface modified controlled pore glass (CPG) nanomaterials. We present several approaches for a single-step chemical modification of 3-propylaminated CPGs that yield highly efficient Ln-extracting materials with distribution coefficients exceeding 10000 mL/g. The resulting Ln complexes were studied using X-ray absorption, magnetic resonance, and time-resolved luminescence spectroscopies. One of these CPG materials involving an imidodi(methanediphosphate) moiety demonstrated high extraction efficacy, significant ionic radius sensitivity, and exceptional tolerance to masking agents, which is conducive to its use for removal of traces of radionuclide ions from aqueous TALSPEAK raffinate (trivalent actinide−lanthanide separation by phosphorus reagent extraction from aqueous complexes process used in processing of spent nuclear fuel). The glass loaded with the extracted metal ions can be calcined and sintered at 1100 °C, yielding fused material that buries Ln ions in the vitreous matrix. This processing temperature is significantly lower than 1700 °C that is required for direct vitrification of lanthanide oxides in high-silica glass. X-ray absorption spectroscopy and acid leaching tests indicate that the immobilized ions are isolated and dispersed in the fused glass matrix. Thus, the method integrates Ln ions into the glass network. The resulting glass can be used for temporary storage or as the source of silica for production of borosilicate waste forms that are used for long-term disposal of high level radioactive waste. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie102494r