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Next Generation Extractants for Cesium Separation from High-Level Waste: From Fundamental Concepts to Site Implementation

Description: Solvent extraction with a lipophilic calix[4]arenebiscrown-6 ligand is currently the selected technology for removal of radioactive cesium-137 from DOE nuclear wastes. In this collaborative DOE-EMSP project, related ''second-generation'' extractants are being synthesized at Texas Tech University (TTU) and their alkali metal cation complexation and separation abilities evaluated at TTU and Oak Ridge National Laboratory (ORNL). The novel feature of the ''second-generation'' calix[4]arenecrown ext… more
Date: June 1, 2005
Creator: Bartsch, Richard A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chapter 8: Selective Stoichiometric and Catalytic Reactivity in the Confines of a Chiral Supramolecular Assembly

Description: Nature uses enzymes to activate otherwise unreactive compounds in remarkable ways. For example, DNases are capable of hydrolyzing phosphate diester bonds in DNA within seconds,[1-3]--a reaction with an estimated half-life of 200 million years without an enzyme.[4] The fundamental features of enzyme catalysis have been much discussed over the last sixty years in an effort to explain the dramatic rate increases and high selectivities of enzymes. As early as 1946, Linus Pauling suggested that enzy… more
Date: September 27, 2007
Creator: University of California, Berkeley; Laboratory, Lawrence Berkeley National; Raymond, Kenneth; Pluth, Michael D.; Bergman, Robert G. & Raymond, Kenneth N.
Item Type: Refine your search to only Book
Partner: UNT Libraries Government Documents Department
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Metal ion complexation by ionizable crown ethers. Progress report, January 1, 1991--December 31, 1993

Description: Cyclic and acyclic polyether compounds with pendent carboxylic acid, phosphonic acid monoethyl ester, sulfonic acid, phosphinic acid and hydroxamic acid groups have been synthesized. The proton-ionizable polyethers can come with and without lipophilic groups. Two types of lipophilic di-ionizable lariat ethers have been prepared. Conformations of proton-ionizable lariat ethers have been probed. Competitive alkali metal cation transport by syn-(decyl)dibenzo-16-crown-5-oxyacetic acid and lipophil… more
Date: July 1, 1993
Creator: Bartsch, R. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Using 15-crown-5, 18-crown-6 and dicyclohexano-18-crown-6 for Am, Ce, Eu and Cm extraction from acid solutions

Description: The extraction from nitric acid of Am, Eu, Ce, Cm(III) tracers by 15-crown-5 (15C5), 18-crown-6 (18C6), dicyclohexano-18-crown-6 (DCH18C6) as well as mixtures of crown ethers and chlorinated cobalt dicarbollide (ChCoD) in nitrobenzene solutions has been investigated. It was revealed that 18C6 is selective for Ce, Am and Cm compared with Eu. The addition of 18C6 to a solution of ChCoD allows Am and Cm to be separated from lanthanides by using this extractant more efficiently. The separation fact… more
Date: August 1, 1994
Creator: Romanovski, V. V.; Proyaev, V. V. & Wester, D. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A new family of anion receptors and their effects on ion pair dissociation and conductivity of lithium salts in non-aqueous solutions

Description: A new family of anion receptors based on aza-ether compounds have been synthesized. Since the anion complexation of these compounds is not based on either positively charged sites or hydrogen bonding, they have a potential to be used in lithium batteries as electrolyte additives. When these compounds are added into nonaqueous electrolytes using lithium salts, such as LiCl/BF or LiBr/THF, the ionic conductivity can be dramatically increased. Near Edge X-ray Absorption Fine Structure (NF-XAFS) sp… more
Date: August 1, 1994
Creator: Lee, H. S.; Yang, X. Q.; McBreen, J. & Okamoto, Y.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Alternative Donor--Acceptor Stacks from Crown Ethers and Naphthalene Diimide Derivatives: Rapid, Selective Formation from Solution and Solid State Grinding

Description: Self assembling {pi}-conjugated molecules into ordered structures are of increasing interest in the field of organic electronics. One particular example is charge transfer complexes containing columnar alternative donor-acceptor (ADA) stacks, where neutral and ionic ground states can be readily tuned to modulate electrical, optical, and ferroelectrical properties. Aromatic-aromatic and charge transfer interactions have been the leading driving forces in assisting the self-assembly of ADA stacks… more
Date: January 22, 2009
Creator: Lawrence Berkeley National Laboratory. Advanced Light Source.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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CSSX Radiolytic H2 Generation ("Thermolysis") -- Final Report

Description: The purpose of this work was to determine the radiolytic hydrogen gas yield of irradiated CSSX solvent at several temperatures. The active ingredient of this solvent is calix[4]arene-bis-(t-octylbenzo) crown-6, a calixarene crown ether used for cesium complexation. The solvent also contains 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol, a fluorinated alcoholic solvent modifer used to improve the solubility of the calixarene and its cesium complex in the Isopar L diluent. Isop… more
Date: January 1, 2009
Creator: Mincher, Bruce J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of the Hydraulic Capacity and Mass Transfer Efficiency of the CSSX Process with the Optimized Solvent in a Single Stage of 5.5-cm-Diameter Centrifugal Contactor

Description: The Caustic-Side Solvent Extraction (CSSX) process has been selected for the separation of cesium from Savannah River Site high-level waste. The solvent composition used in the CSSX process was recently optimized so that the solvent is no longer supersaturated with respect to the calixarene crown ether extractant. Hydraulic performance and mass transfer efficiency testing of a single stage of 5.5-cm ORNL-designed centrifugal contactor has been performed for the CSSX process with the optimized s… more
Date: September 1, 2002
Creator: Law, Jack Douglas; Tillotson, Richard Dean & Todd, Terry Allen
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation of Sodium Salts

Description: The purpose of this research involving collaboration between Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) is to explore new approaches to the separation of sodium hydroxide, sodium nitrate, and other sodium salts from high-level alkaline tank waste. The principal potential benefit is a major reduction in disposed waste volume, obviating the building of expensive new waste tanks and reducing the costs of low-activity waste immobilization. Principles of io… more
Date: June 1, 2005
Creator: Levitskaia, Tatiana G.; Lumetta, Gregg J.; Moyer, Bruce A. & Bonnesen, Peter V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation of Sodium Salts

Description: The purpose of this research involving collaboration between Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) is to explore new approaches to the separation of sodium hydroxide, sodium nitrate, and other sodium salts from high-level alkaline tank waste. The principal potential benefit is a major reduction in disposed waste volume, obviating the building of expensive new waste tanks and reducing the costs of low-activity waste immobilization. Principles of io… more
Date: June 1, 2006
Creator: Levitskaia, Tatiana G.; Lumetta, Gregg J.; Moyer, Bruce A. & Bonnesen, Peter V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation of Sodium Salts

Description: The purpose of this research involving collaboration between Oak Ridge National Laboratory (ORNL) and Pacific Northwest National Laboratory (PNNL) is to explore new approaches to the separation of sodium hydroxide, sodium nitrate, and other sodium salts from high-level alkaline tank waste. The principal potential benefit is a major reduction in disposed waste volume, obviating the building of expensive new waste tanks and reducing the costs of vitrification. Principles of ion recognition are be… more
Date: September 26, 2005
Creator: Moyer, Bruce A.; Bonnesen, Peter V.; Custelcean, Radu; Delmau, Laetitia H.; Engle, Nancy L.; Kang, Hyun-Ah et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solvent Effects on Metal Complexation with Crown Ethers from Liquid to Supercritical Fluids (DE-FG07-98ER 149 13)

Description: The purpose of this project is to study the salvation effects of metal-crown ether complexation in different solvents. It has been suggested in the literature that supercritical fluid carbon dioxide (SF-CO2) is a tunable solvent because its salvation environment can be varied with the fluid density. In this project, spectroscopic techniques including nuclear magnetic resonance (NMR) and Fourier Transform Infrared (FTIR) were used to evaluate salvation effects of metal crown complexation in orga… more
Date: June 1, 2002
Creator: Wai, C.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation of Sodium Salts

Description: In this project, now completing its third year of its second renewal period, a collaborative project involving Oak Ridge National Laboratory, Pacific Northwest National Laboratory, and the University of North Texas has been addressing outstanding questions regarding the separation of the bulk sodium constituents of alkaline tank waste. The principal potential benefit of this research is a major reduction in the volume of radioactive tank waste, obviating the building of expensive new tanks and … more
Date: June 30, 2004
Creator: Moyer, Bruce A.; Marchand, Alan P. & Lumetta, Gregg J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ion Recognition Approach to Volume Reduction of Alkaline Tank Waste by Separation of Sodium Salts

Description: In this project, now completing its third year of its second renewal period, a collaborative project involving Oak Ridge National Laboratory, Pacific Northwest National Laboratory, and the University of North Texas has been addressing outstanding questions regarding the separation of the bulk sodium constituents of alkaline tank waste. The principal potential benefit of this research is a major reduction in the volume of radioactive tank waste, obviating the building of expensive new tanks and … more
Date: June 30, 2004
Creator: Moyer, Bruce A.; Marchand, Alan P. & Lumetta, Gregg J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mass Spectrometric Fingerprinting of Tank Waste Using Tunable, Ultrafast Infrared Lasers

Description: During the past year, we have initiated systematic studies of mass spectrometry of model tank-waste materials using both conventional nanosecond, single-frequency and tunable, subpicosecond mid-infrared lasers. In addition to making initial measurements, we have also constructed several new items of equipment for the experiment and begun to develop a model of the processes which lead to efficient desorption and ionization of organic molecules (e.g., toluene, benzene, crown ethers) from sodium n… more
Date: June 1, 1999
Creator: Haglund, Richard F., Jr. & Hess, Wayne P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DESIGN AND SYNTHESIS OF THE NEXT GENERATION OF CROWN ETHERS FOR WASTE SEPARATIONS: AN INTER-LABORATORY COMPREHENSIVE PROPOSAL

Description: The objectives of this project were to develop the techniques, materials, and fundamental understanding necessary to solve difficult separations problems of the USDOE in the 21st century. The specific goals included developing new, powerful molecular modeling tools for ligand design, performing computational and structural studies to reveal fundamental properties of ligand-metal ion interactions, studying solvent extraction behavior to provide basic understanding of solution speciation and equi… more
Date: December 2000
Creator: Moyer, Bruce A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solvent Effects on Cesium Complexation with Crown Ethers from Liquid to Supercritical Fluids

Description: Nuclear magnetic resonance (NMR) techniques were used to study crown ether-water interactions in solvents of low dielectric constants such as chloroform and carbon tetrachloride. Water forms a 1:1 complex with a number of crown ethers including 12-crown-4, 15-crown-5, 18-crown-6, dicyclohexano-18=crown-6, dicyclohexano-24-crown 8, and dibenzl-24-crown-8 in chloroform. Among these crown ethers, the 18-crown-6-H2 complex has the largest equilibrium constant (K=545) and 97% of the crown is complex… more
Date: March 15, 2004
Creator: Wai, Chien M.; Rustenholtz, Anne; Wang, Shaofen; Lee, Su-Chen; Herman, Jamie & Porter, Richard A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optically-Based Array Sensors for Selective In Situ Analysis of tank Waste

Description: The objective of this research program is to conduct the fundamental research necessary to develop an array of chemically selective sensors, based on highly selective molecular recognition agents and highly sensitive fluorescence techniques, that can be coupled to fiber optics for remote analytical applications. These sensors will be of great value to DOE for the safe and cost-effective in situ characterization of high level waste tanks and other applications where remote sensing will prevent w… more
Date: June 1, 2000
Creator: Brown, Gilbert M.; Dabestani, Reza; Bonnesen, Peter V. & Walt, David R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solution Effects on Cesium Complexation with Calixarene - Crown Ethers from Liquid to Supercritical Fluids

Description: Supercritical fluid CO2 is an alternative solvent for extraction of metals. The solubility parameter of supercritical CO2 varies with density resembling that of liquid hexane at moderate pressures in the supercritical region to those of chlorinated solvents at very high pressures. By changing density of supercritical CO2, the solvation environment of a metal chelate system can vary continuously and resembles over a wide range of solvents. Thus, supercritical CO2 provides a unique system for stu… more
Date: June 1, 1999
Creator: Wai, Chien M. & Yonker, Clem
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Optically-Based Array Sensors For Selective In Situ Analysis Of Tank Waste

Description: The objective of this research program is to conduct the fundamental research necessary to develop an array of chemically-selective sensors, based on highly selective molecular recognition agents and highly sensitive fluorescence techniques, that can be coupled to fiber optics for remote analytical applications. The ability to detect and measure specific chemicals and radionuclides directly inside a high level waste tank using a remote sensing device could result in considerable benefits with r… more
Date: March 31, 2001
Creator: Brown, Gilbert M.; Dabestani, Reza; Connesen, Peter V. & Walt, David R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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81929 - Fission-Product Separation Based on Room - Temperature Ionic Liquids

Description: This project has demonstrated that Sr2+ and Cs+ can be selectively extracted from aqueous solutions into ionic liquids using crown ethers and that unprecedented large distribution coefficients can be achieved for these fission products. The volume of secondary wastes can be significantly minimized with this new separation technology. Through the current EMSP funding, the solvent extraction technology based on ionic liquids has been shown to be viable and can potentially provide the most efficie… more
Date: December 9, 2004
Creator: Rogers, Robin D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Next Generation Extractants for Cesium Separation from High-Level Waste: From Fundamental Concepts to Site Implementation

Description: Calix[4]arenebiscrown-6 molecules are currently the selected technology for removal of radioactive cesium-137 from DOE nuclear wastes. By attachment of an acidic function to such molecules, the efficiency with which cesium ion can be extracted from an aqueous solution into an organic diluent is markedly increased since the requirement for concomitant extraction of an aqueous phase anion is avoided. Thus, cesium ion extraction by proton-ionizable calix[4]arenebiscrown-6 molecules may be the ''se… more
Date: June 1, 2003
Creator: Moyer, Bruce A. & Bartsch, Richard A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mass Spectrometric Fingerprinting of Tank Waste Using Tunable, Ultrafast Infrared Lasers

Description: The principal scientific thrust of this project was to demonstrate a novel method for precision matrix-assisted laser desorption-ionization (MALDI) mass spectrometry (MS) of model tank-waste materials using, using the sodium nitrate component of the tank waste both as the matrix and as an internal calibration standard. Conventional nanosecond and femtosecond single-frequency lasers and a tunable, mid-infrared free-electron laser were used in the development of the MS protocols and in measuremen… more
Date: August 6, 2002
Creator: Haglund, Richard, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Process for the extraction of strontium from acidic solutions

Description: The invention is a process for selectively extracting strontium values from aqueous nitric acid waste solutions containing these and other fission product values. The extractant solution is a macrocyclic polyether in an aliphatic hydrocarbon diluent containing a phase modifier. The process will selectively extract strontium values from nitric acid solutions which are up to 6 molar in nitric acid.
Date: January 1, 1993
Creator: Horwitz, E.P. & Dietz, M.L.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
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