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Effect of alpha-radiolysis on TRUEX-NPH solvent

Description: An unexpectedly high degradation of the TRUEX (TRansUranic EXtraction) solvent occurred during the treatment of waste solutions from the New Brunswick Laboratory. The waste solutions treated contained approximately 1 g/L of Pu-239 and 20 mg/L of Am-241. Earlier studies of {alpha}-radiolysis using carbon tetrachloride (CCl{sub 4}) rather than normal paraffinic hydrocarbons (NPH) as a diluent indicated greater resistance to radiation damage than observed. For this study, the TRUEX-NPH solvent was… more
Date: October 1, 1994
Creator: Buchholz, B. A.; Nunez, L. & Vandegrift, G. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Waste remediation using in situ magnetically assisted chemical separation

Description: The magnetically assisted chemical separation process (MACS) combines the selective and efficient separation afforded by chemical sorption with the magnetic recovery of ferromagnetic particles. This process is being developed for treating the underground storage tanks at Hanford. These waste streams contain cesium, strontium, and transuranics (TRU) that must be removed before this waste can be disposed of as grout. The separation process uses magnetic particles coated with either (1) a selectiv… more
Date: November 1, 1993
Creator: Nunez, L.; Buchholz, B. A. & Vandegrift, G. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and demonstration of the TRUEX solvent extraction process

Description: The Generic TRUEX Model (GTM) was developed for use in designing site and feed-specific TRUEX flowsheets and in estimating the space and cost requirements for installing a TRUEX process. This paper discusses data collected in support of the GTM and its use in (1) designing process flowsheets and (2) performing sensitivity analyses. Demonstration of the TRUEX process is underway at Argonne National Laboratory (ANL), where plutonium-containing analytical waste solutions generated at the DOE New B… more
Date: March 1, 1993
Creator: Vandegrift, G. F.; Chamberlain, D. B.; Conner, C.; Copple, J. M.; Dow, J. A.; Everson, L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Basic TRUEX process for Rocky Flats Plant

Description: The Generic TRUEX Model was used to develop a TRUEX process flowsheet for recovering the transuranics (Pu, Am) from a nitrate waste stream at Rocky Flats Plant. The process was designed so that it is relatively insensitive to changes in process feed concentrations and flow rates. Related issues are considered, including solvent losses, feed analysis requirements, safety, and interaction with an evaporator system for nitric acid recycle.
Date: August 1, 1994
Creator: Leonard, R. A.; Chamberlain, D. B.; Dow, J. A.; Farley, S. E.; Nunez, L.; Regalbuto, M. C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Preliminary plan for treating mixed waste

Description: A preliminary waste treatment plan was developed for disposing of radioactive inorganic liquid wastes that contain hazardous metals and/or hazardous acid concentrations at Argonne National Laboratory. This plan, which involves neutralization and sulfide precipitation followed by filtration, reduces the concentration of hazardous metals and the acidity so that the filtrate liquid is simply a low-level radioactive waste that can be fed to a low-level waste evaporator.
Date: June 1, 1993
Creator: Vandegrift, G. F.; Conner, C.; Hutter, J. C.; Leonard, R. A.; Nunez, L.; Sedlet, J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Removal of VOCs from groundwater using membrane-assisted solvent extraction

Description: A membrane-assisted solvent extraction (MASX) system coupled to a membrane-assisted distillation stripping (MADS) system for use in decontaminating groundwater is discussed. Volatile organic compounds (VOCs) are extracted in the MASX using a sunflower oil solvent. In the MADS, VOCs are stripped from the sunflower oil, and the oil is recycled to the MASX. Thermodynamic data for the sunflower oil-water-VOCs system were experimentally collected. Published membrane-mass transfer results along with … more
Date: November 1, 1992
Creator: Hutter, J. C.; Vandegrift, G. F.; Nunez, L. & Redfield, D. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development and demonstration of the TRUEX solvent extraction process

Description: The Generic TRUEX Model (GTM) was developed for use in designing site and feed-specific TRUEX flowsheets and in estimating the space and cost requirements for installing a TRUEX process. This paper discusses data collected in support of the GTM and its use in (1) designing process flowsheets and (2) performing sensitivity analyses. Demonstration of the TRUEX process is underway at Argonne National Laboratory (ANL), where plutonium-containing analytical waste solutions generated at the DOE New B… more
Date: January 1, 1993
Creator: Vandegrift, G. F.; Chamberlain, D. B.; Conner, C.; Copple, J. M.; Dow, J. A.; Everson, L. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Removal of VOCs from groundwater using membrane-assisted solvent extraction

Description: A membrane-assisted solvent extraction (MASX) system coupled to a membrane-assisted distillation stripping (MADS) system for use in decontaminating groundwater is discussed. Volatile organic compounds (VOCs) are extracted in the MASX using a sunflower oil solvent. In the MADS, VOCs are stripped from the sunflower oil, and the oil is recycled to the MASX. Thermodynamic data for the sunflower oil-water-VOCs system were experimentally collected. Published membrane-mass transfer results along with … more
Date: January 1, 1992
Creator: Hutter, J. C.; Vandegrift, G. F.; Nunez, L. & Redfield, D. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Superconducting Open-Gradient Magnetic Separation for the Pretreatment of Radioactive or Mixed Waste Vitrification Feeds

Description: An open-gradient magnetic separation (OGMS) process is being considered to separate deleterious elements from radioactive and mixed waste streams prior to vitrification or stabilization. By physically segregating solid wastes and slurries based on the magnetic properties of the solid constituents, this potentially low-cost process may serve the U.S. Department of Energy (DOE) by reducing the large quantities of glass produced from defense-related high-level waste (HLW). Furthermore, the separat… more
Date: December 31, 1999
Creator: Nunez, L.; Kaminsky, M. D.; Doctor, R. D.; Crawford, C. & Ritter, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Magnetically responsive microparticles for targeted drug and radionuclide delivery.

Description: We are currently investigating the use of magnetic particles--polymeric-based spheres containing dispersed magnetic nanocrystalline phases--for the precise delivery of drugs via the human vasculature. According to this review, meticulously prepared magnetic drug targeting holds promise as a safe and effective method of delivering drugs to specific organ, tissue or cellular targets. We have critically examined the wide range of approaches in the design and implementation of magnetic-particle-bas… more
Date: February 16, 2004
Creator: Kaminski, M. D.; Ghebremeskel, A. N.; Nunez, L.; Kasza, K. E.; Chang, F.; Chien, T. H. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Review of arsenic removal technologies for contaminated groundwaters.

Description: This review was compiled to summarize the technologies currently being investigated to remove arsenic from drinking waters, with a special focus on developing and third-world countries where the problem is exacerbated by flooding and depressed economic conditions. The reason for compiling this report is to provide background material and a description of competing technologies currently described in the literature for arsenic removal. Based on the sophistication and applicability of current tec… more
Date: May 2, 2003
Creator: Vu, K. B.; Kaminski, M. D. & Nunez, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Polychlorodibenzo-p-dioxin and polychlorodibenzo-furan removal and destruction.

Description: This report provides a short summary of technologies used to destroy or separate dioxins/furans from environmental samples. It is meant as a resource for developing a technology employing magnetic particles as an engineering vehicle for large-scale, cost-effective destruction of dioxins/furans in fresh waters or sludges/soils.
Date: September 30, 2003
Creator: Patel, S.; Kaminski, M. D. & Nunez, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Evaluation of hydroxamic acid in uranium extraction process : literature review.

Description: The Uranium Extraction (UREX) process is being developed for the spent oxide fuel from light water reactors as part of the Accelerator Transmutation of Waste Project. The UREX process is similar to the Plutonium and Uranium Extraction (PUREX) process in that it involves solvent extraction based on a tributyl phosphate extractant. To assure that actinide reduction and complexation are effective, the reductant/complexant aceto-hydroxamic acid is being considered for use in the UREX process. The f… more
Date: May 21, 2001
Creator: Nunez, L. & Vandegrift, G. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Comparison of the Corrosion Behavior of Tank 51 Sludge-Based Glass and a Nonradioactive Homologue Glass

Description: We are conducting static dissolution tests with a glass made at the Savannah River Technology Center (SRTC) during a demonstration of the Defense Waste Processing Facility (DWPF) process control for remote vitrification [1]. The glass was made with sludge from Tank 5 1, SRL 202 frit, and added soda. This glass is similar to waste glasses being made in the current DWPF campaign. Parallel tests are being conducted with a nonradioactive glass made at ANL having the same composition as the radioact… more
Date: December 31, 1996
Creator: Nunez, L.; Ebert, W.L.; Wolf, S.F. & Bates, J.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development program for magnetically assisted chemical separation: Evaluation of cesium removal from Hanford tank supernatant

Description: Magnetic particles (MAG*SEP{sup SM}) coated with various absorbents were evaluated for the separation and recovery of low concentrations of cesium from nuclear waste solutions. The MAG*SEP{sup SM} particles were coated with (1) clinoptilolite, (2) transylvanian volcanic tuff, (3) resorcinol formaldehyde, and (4) crystalline silico-titanate, and then were contacted with a Hanford supernatant simulant. Particles coated with the crystalline silico-titanate were identified by Bradtec as having the … more
Date: December 1, 1994
Creator: Nunez, L.; Buchholz, B. A.; Ziemer, M.; Dyrkacz, G.; Kaminski, M.; Vandegrift, G. F. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Review and Evaluation of Extractants for Strontium Removal using Magnetically Assisted Chemical Separation

Description: A literature review on extractants for strontium removal was initially performed at Northern Illinois University to assess their potential in magnetically assisted chemical separation. A series of potential strontium extractants was systematically evaluated there using radioanalytical methods. Initial experiments were designed to test the uptake of strontium from nitric acid using several samples of magnetic extractant particles that were coated with various crown ether ligands. High partition … more
Date: November 1, 1995
Creator: Bauer, C. B.; Rogers, R. D.; Nunez, L.; Ziemer, M. D.; Pleune, T. T. & Vandegrift, G. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of single ion activity coefficients to determine solvent extraction mechanism for components of high level nuclear waste

Description: The TRUEX solvent extraction process is being developed to remove and concentrate transuranic (TRU) elements from high-level and TRU radioactive wastes currently stored at US Department of Energy sites. Phosphoric acid is one of the chemical species of concern at the Hanford site where bismuth phosphate was used to recover plutonium. The mechanism of phosphoric acid extraction with TRUEX-NPH solvent at 25{degrees}C was determined by phosphoric acid distribution ratios, which were measured by us… more
Date: December 31, 1995
Creator: Nunez, L. & Vandegrift, G.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Transuranic separation using organophophorus extractants adsorbed onto superparamagnetic carriers.

Description: Polymeric coated ferromagnetic carriers with an absorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted by tributyl phosphate (TBP) are being evaluated for application in the separation and the recovery of low concentrations of americium, plutonium, and uranium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles and the complexed particles can be recovered fr… more
Date: October 7, 1998
Creator: Nunez, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Superconducting open-gradient magnetic separation for the pretreatment of radioactive or mixed waste vitrification feeds. 1997 annual progress report

Description: 'Vitrification has been selected as a final waste form technology in the US for long-term storage of high-level radioactive wastes (HLW). However, a foreseeable problem during vitrification in some waste feed streams lies in the presence of elements (e.g., transition metals) in the HLW that may cause instabilities in the final glass product. The formation of spinel compounds, such as Fe{sub 3}O{sub 4} and FeCrO{sub 4}, results in glass phase separation and reduces vitrifier lifetime, and durabi… more
Date: October 2, 1997
Creator: Doctor, R.; Nunez, L.; Cicero-Herman, C. A.; Ritter, J. A. & Landsberger, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Magnetically assisted chemical separation (MACS) process: Preparation and optimization of particles for removal of transuranic elements

Description: The Magnetically Assisted Chemical Separation (MACS) process combines the selectivity afforded by solvent extractants with magnetic separation by using specially coated magnetic particles to provide a more efficient chemical separation of transuranic (TRU) elements, other radionuclides, and heavy metals from waste streams. Development of the MACS process uses chemical and physical techniques to elucidate the properties of particle coatings and the extent of radiolytic and chemical damage to the… more
Date: May 1, 1995
Creator: Nunez, L.; Kaminski, M.; Bradley, C.; Buchholz, B. A.; Aase, S. B.; Tuazon, H. E. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Decontamination of control rod housing from Palisades Nuclear Power Station.

Description: Argonne National Laboratory has developed a novel decontamination solvent for removing oxide scales formed on ferrous metals typical of nuclear reactor piping. The decontamination process is based on the properties of the diphosphonic acids (specifically 1-hydroxyethane-1,1-diphosphonic acid or HEDPA) coupled with strong reducing-agents (e.g., sodium formaldehyde sulfoxylate, SFS, and hydroxylamine nitrate, HAN). To study this solvent further, ANL has solicited actual stainless steel piping mat… more
Date: May 3, 1999
Creator: Kaminski, M.D.; Nunez, L. & Purohit, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiolysis and hydrolysis of magnetically assisted chemical separation particles

Description: The magnetically assisted chemical separation (MACS) process is designed to separate transuranic (TRU) elements out of high-level waste (HLW) or TRU waste. Magnetic microparticles (1--25 {mu}m) were coated with octyl (phenyl)N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) dissolved in tributyl phosphate (TBP) and tested for removing TRU elements from acidic nitrate solutions. The particles were contacted with nitric acid solutions and Hanford plutonium finishing plant (PFP) simulant, irradi… more
Date: May 1, 1995
Creator: Buchholz, B. A.; Nunez, L. & Vandegrift, G. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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