48 Matching Results

Search Results

Advanced search parameters have been applied.

Actinide production in /sup 136/Xe bombardments of /sup 249/Cf

Description: The production cross sections for the actinide products from /sup 136/Xe bombardments of /sup 249/Cf at energies 1.02, 1.09, and 1.16 times the Coulomb barrier were determined. Fractions of the individual actinide elements were chemically separated from recoil catcher foils. The production cross sections of the actinide products were determined by measuring the radiations emitted from the nuclides within the chemical fractions. The chemical separation techniques used in this work are described in detail, and a description of the data analysis procedure is included. The actinide production cross section distributions from these /sup 136/Xe + /sup 249/Cf bombardments are compared with the production cross section distributions from other heavy ion bombardments of actinide targets, with emphasis on the comparison with the /sup 136/Xe + /sup 248/Cm reaction. A technique for modeling the final actinide cross section distributions has been developed and is presented. In this model, the initial (before deexcitation) cross section distribution with respect to the separation energy of a dinuclear complex and with respect to the Z of the target-like fragment is given by an empirical procedure. It is then assumed that the N/Z equilibration in the dinuclear complex occurs by the transfer of neutrons between the two participants in the dinuclear complex. The neutrons and the excitation energy are statistically distributed between the two fragments using a simple Fermi gas level density formalism. The resulting target-like fragment initial cross section distribution with respect to Z, N, and excitation energy is then allowed to deexcite by emission of neutrons in competition with fission. The result is a final cross section distribution with respect to Z and N for the actinide products. 68 refs., 33 figs., 6 tabs.
Date: August 1, 1985
Creator: Gregorich, K.E.
Partner: UNT Libraries Government Documents Department

Actinide removal from nitric acid waste streams

Description: Actinide separations research at the Rocky Flats Plant (RFP) has found ways to significantly improve plutonium secondary recovery and americium removal from nitric acid waste streams generated by plutonium purification operations. Capacity and breakthrough studies show anion exchange with Dowex 1x4 (50 to 100 mesh) to be superior for secondary recovery of plutonium. Extraction chromatography with TOPO(tri-n-octyl-phosphine oxide) on XAD-4 removes the final traces of plutonium, including hydrolytic polymer. Partial neutralization and solid supported liquid membrane transfer removes americium for sorption on discardable inorganic ion exchangers, potentially allowing for non-TRU waste disposal.
Date: January 1, 1986
Creator: Muscatello, A.C. & Navratil, J.D.
Partner: UNT Libraries Government Documents Department


Description: The aging of the US nuclear stockpile presents a number of challenges, including the ever-increasing radioactivity of plutonium residues from {sup 241}Am. Minimization of this weak gamma-emitter in process and waste solutions is desirable to reduce both worker exposure and the effects of radiolysis on the final waste product. Removal of americium from plutonium nitric acid processing effluents, however, is complicated by the presence of large.quantities of competing metals, particularly Fe and Al, and-strongly oxidizing acidic solutions. The reprocessing operation offers several points at which americium removal maybe attempted, and we are evaluating two classes of materials targeted at different steps in the process. Extraction chromatography resin materials loaded with three different alkylcarbamoyl phosphinates and phosphine oxides were accessed for Am removal efficiency and Am/Fe selectivity from 1-7 molar nitric acid solutions. Commercial and experimental mono- and bifunctional anion-exchange resins were evaluated for total alpha-activity removal from post-evaporator solutions whose composition, relative to the original nitric acid effluent, is reduced in acid and greatly increased in total salt content. With both classes of materials, americium/total alpha emission removal is sufficient to meet regulatory requirements even under sub-optimal conditions. Batch distribution coefficients, column performance data, and the effects of Fe-masking agents will be presented.
Date: August 1, 2000
Creator: BARR, M.; JARVINEN, G. & AL, ET
Partner: UNT Libraries Government Documents Department

Analytical support for characterization of americium-curium solution at SRS

Description: Americium-Curium (Am-Cm) solution in F-Canyon was produced during the Mk 40 and Mk 41 campaigns in the mid and late 1970`s. The Savannah River Site (SRS) Central Laboratory recently characterized this important solution of nuclear material to enable assessment by Westinghouse Savannah River Company and Department of Energy of disposition options. The tank had last been sampled and analyzed in 1986. A wide range of analyses were performed to determine the tank contents. New radiochemical column separation methods were developed to fully characterize the solution for actinides, metals, anions, and isotopics to support the disposition study in a timely manner. Current disposition is to perform a vitrification process on the Am/Cm solution at SRS to produce glass canisters for safe shipment and storage of this material. The SRS Am/Cm waste solution will be converted, in effect, to a product for an outside customer. Oak Ridge National Laboratory. To support the Am/Cm vitrification processing, process support analyses are required after completion of denitration, precipitation and redissolution steps. Full elemental chemistry characterization will be required on the final melter feed solution.
Date: October 1, 1996
Creator: Maxwell, S.L. III & Nelson, M.R.
Partner: UNT Libraries Government Documents Department

Application of extraction chromatography to actinide decontamination of hydrochloric acid effluent streams

Description: Extraction chromatography is under development as a method to lower actinide activity levels in effluent steams. Successful application of this technique for radioactive liquid waste treatment would provide a low activity feed stream for HCl recycle, reduce the loss of radioactivity to the environment in aqueous effluents, and would lower the quantity and reduce the hazard of the associated solid waste. The extraction of Pu and Am from HCl solutions was examined for several commercial and laboratory-produced sorbed resin materials. Inert supports included silica and polymer beads of differing mesh sizes. The support material was coated with either n-octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (O-CMPO) or di-(4-t-butylphenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (D-CMPO) as an extractant, and using either tributyl phosphate (TBP) or diamyl amylphosphonate (DAAP) as a diluent. Solutions tested were effluent streams generated by ion exchange and solvent extraction recovery of Pu. A finer mesh silica support material demonstrated advantages in removal of trivalent Am in some tests, but also showed a tendency toward plugging and channeling as column sizes and flow rates were increased. Larger bead sizes showed better physical properties as the process was scaled up to removal of gram quantities of Am from large effluent volumes. The ratio of extractant to diluent also appeared to play a role in the retention of Am. In direct comparative studies, when loaded on identical supports and diluent conditions, D-CMPO demonstrated better Am retention than O-CMPO from HCl process effluents.
Date: May 1, 1996
Creator: Schulte, L.D.; McKee, S.D. & Salazar, R.R.
Partner: UNT Libraries Government Documents Department

Applications of DHDECMP extraction chromatography to nuclear analytical chemistry

Description: Dihexyl-N,N-diethylcarbamylmethylenephosphonate (DHDECMP) is a highly selective extractant for actinides and lanthanides. This reagent, extensively studied for process-scale operations, also has valuable analytical applications. Extraction chromatographic columns of DHDECMP, supported on inert, porous, polymer beads effectively separate most metallic impurity elements from the retained inner transition elements. The retained elements can be separated into individual fractions of (1) lanthanides, (2) americium, (3) plutonium, and (4) uranium by mixed-solvent anion exchange.
Date: January 1, 1981
Creator: Marsh, S.F. & Simi, O.R.
Partner: UNT Libraries Government Documents Department

Arsenic speciation using high performance liquid chromatography-inductively coupled plasma-mass spectrometry

Description: A method has been developed by Argonne National Laboratory to identify and quantify As(III), As(V), and organoarsenic compounds in environmental samples. A arsenic species were separated by reversed-phase, ion-pairing, HPLC using a microbore Inertsil-ODS{trademark} column. Only 1 {micro}L of sample was injected on the column, and the mobile phase flow rates were typically on the order of 40 {micro}L/min. The HPLC mobile phase was a mixture of methanol and tetrabutylammonium hydroxide (TBAH), and the column effluent was introduced into an ICP-mass spectrometer using direct injection nebulization. Detection limits of less than 1 pg As (as injected on the column) were easily obtained for each arsenic species. The effect of changes in mobile phase composition and ICP-MS conditions will be described, as well as quality control measures, e.g., the use of surrogates, internal standards, and matrix spikes. Precision and accuracy information will be presented from the analysis of aqueous standards and soil extracts that were spiked with arsenic oxide [As(III)], sodium arsenate [As(V)], dimethylarsinic acid (DMAA), or chlorovinyl arsenious acid (CVAA). The authors believe that these data demonstrate the utility of this technique for the sensitive determination of arsenic species present in water or soil.
Date: August 1995
Creator: Bass, D. A.; Yaeger, J. S.; Crain, J. S.; Kiely, J. T.; Parish, K. J.; Gowdy, M. J. et al.
Partner: UNT Libraries Government Documents Department

Calculation of Transactinide Homolog Isotope Production Reactions Possible with the Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory

Description: The LLNL heavy element group has been investigating the chemical properties of the heaviest elements over the past several years. The properties of the transactinides (elements with Z > 103) are often unknown due to their low production rates and short half-lives, which require lengthy cyclotron irradiations in order to make enough atoms for statistically significant evaluations of their chemistry. In addition, automated chemical methods are often required to perform consistent and rapid chemical separations on the order of minutes for the duration of the experiment, which can last from weeks to months. Separation methods can include extraction chromatography, liquid-liquid extraction, or gas-phase chromatography. Before a lengthy transactinide experiment can be performed at an accelerator, a large amount of preparatory work must be done both to ensure the successful application of the chosen chemical system to the transactinide chemistry problem being addressed, and to evaluate the behavior of the lighter elemental homologs in the same chemical system. Since transactinide chemistry is literally performed on one single atom, its chemical properties cannot be determined from bulk chemical matrices, but instead must be inferred from the behavior of the lighter elements that occur in its chemical group and in those of its neighboring elements. By first studying the lighter group homologs in a particular chemical system, when the same system is applied to the transactinide element under investigation, its decay properties can be directly compared to those of the homologues, thereby allowing an inference of its own chemistry. The Center for Accelerator Mass Spectrometry (CAMS) at Lawrence Livermore National Laboratory (LLNL) includes a 1 MV Tandem accelerator, capable of accelerating light ions such as protons to energies of roughly 15 MeV. By using the CAMS beamline, tracers of transactinide homolog elements can be produced both for development of chemical systems and for ...
Date: November 29, 2011
Creator: Moody, K J; Shaughnessy, D A & Gostic, J M
Partner: UNT Libraries Government Documents Department

Characterization of Group V Dubnium Homologs on DGA Extraction Chromatography Resin from Nitric and Hydrofluoric Acid Matrices

Description: Studies of the chemical properties of superheavy elements (SHE) pose interesting challenges due to their short half-lives and low production rates. Chemical systems must have extremely fast kinetics, fast enough kinetics to be able to examine the chemical properties of interest before the SHE decays to another nuclide. To achieve chemistry on such time scales, the chemical system must also be easily automated. Most importantly however, a chemical system must be developed which provides suitable separation and kinetics before an on-line study of a SHE can be performed. Relativistic effects make studying the chemical properties of SHEs interesting due to the impact these effects could have on the SHEs chemical properties. Relativistic effects arise when the velocity of the s orbital electrons approach the speed of light. As this velocity increases, the Bohr radius of the inner electron orbitals decreases and there is an increase in the particles mass. This contraction results in a destabilization of the energy of the outer d and f electron orbitals (5f and 6d in the case of SHE), which can cause these to expand due to their increased shielding from the nuclear charge. Another relativistic effect is the spin-orbit splitting for p, d, and f orbitals into j = 1 {+-} 1/2 states. This can lead most interestingly to a possible increased stability of element 114, which due to large spin-orbit splitting of the 7p orbital and the relativistically stabilized 7p{sub 1/2} and 7s orbital gives rise to a closed shell ground state of 7s{sup 2}7p{sub 1/2}{sup 2}. The homologs of element 105, dubnium (Db), Ta and Nb and the pseudo-homolog Pa, are well known to hydrolyze and form both neutral and non-neutral monoatomic and polyatomic species that may cause issues with extraction from a given chemical system. Early ion-exchange and solvent-extraction studies show ...
Date: February 21, 2012
Creator: Despotopulos, J D & Sudowe, R
Partner: UNT Libraries Government Documents Department

Chemical research at Rocky Flats

Description: An overview of the research projects in the Chemical Research group will be given. The work involves actinide waste and processing chemistry, separations chemistry, radiation studies, and calorimetry and thermodynamics. Details will be given of the actinide separations research, including work with macroreticular anion exchangers and bidentate organophosphorus extractants.
Date: February 27, 1978
Creator: Navratil, J. D.
Partner: UNT Libraries Government Documents Department

Chemical Treatment of US Department of Energy High Level and Low Level Waste to Obtain a Pure Radiochemical Fraction for Determination of Californium Alpha-Decay Content

Description: We have developed a chemical separation technique that allows the radiochemical determination of the californium a-decay content in Department of Energy (DOE) high level wastes from the Hanford and Savannah River sites. The chemical separation technique uses a series of column extraction chromatography steps that use Eichrom Industries' lanthanide and actinide plus 3 oxidation state selective Ln-resin(R) and the transuranic selective plus 4 oxidation state TRU-resin(R) to obtain intermediate product phases in dilute nitric acid. The technique has been demonstrated on three types of authentic DOE high and low level waste samples. We obtain discrimination from Pu a-activity by a factor of over 200 and from Cm-244 a-activity by a factor approaching 1700. Californium recoveries are measured by addition of a Cf-249 spike and are in the range of 50 percent to 90 percent in the synthetic samples and are in the range of 1.4 percent to 48 percent for the authentic DOE waste samples.
Date: December 2, 2002
Creator: Dewberry, R.
Partner: UNT Libraries Government Documents Department

Chemistry Research and Development. Progress Report, July 1977--April 1978

Description: The following studies are reported on: calorimetry and thermodynamics of nuclear materials; actinide recovery and purification; optimization of the cation exchange process for recovering americium and plutonium from molten salt extraction residues; decontamination of soil; secondary actinide recovery; evaluation of tributyl phosphate-impregnated sorbent for plutonium-uranium separations; comparison of cation exchange recovery of actinides from the NaCl--KCl--MgCl/sub 2/ and CaCl/sub 2/--KCl--MgCl/sub 2/ systems; combined anion exchange-bidentate organophosphorous extraction process for molten salt extraction residues; recovery of actinides from combustible wastes; actinide recovery and recycle preparation for waste streams; processing Leco crucible residues containing a tin accelerator; dissolution of refractory residues in hydrochloric acid; metal distillation; induction-heated, tilt-pour furnace; plutonium from backlog salts; and plutonium peroxide precipitation process. (LK)
Date: November 8, 1978
Creator: Miner, F. J.
Partner: UNT Libraries Government Documents Department

Chemistry research and development. Progress report, November 1978-April 1979

Description: The status of the following studies is given: calorimetry and thermodynamics of nuclear materials; americium recovery and purification; optimization of the cation exchange process for recovering americium and plutonium from molten net extraction residues; evaluation and comparison of bidentate extractants and methods for actinide recovery; a combined anion exchange-bidontate organophosphorus extraction process for molten salt extraction residues; a combined anion exchange-extraction chromatography technique for secondary recovery; plutonium recovery in the Advanced Size Reduction Facility; decontamination of Rocky Flats soil; separating lead and calcium from americium by chromate and oxalate precipitation; demonstration of the pyroredox process in the induction-heated, tilt-pour furnace; process development for recovery of americium from vacuum melt furnace crucibles; plutonium peroxide precipitation process; and a comparative study of annular and Raschig ring-filled tanks.
Date: October 5, 1979
Creator: Miner, F. J.
Partner: UNT Libraries Government Documents Department

Comparison between CMPO and DHDECMP for alpha decontamination of radioactive liquid waste

Description: Ion exchange is the major method used at Los Alamos to recover and purify plutonium from a variety of different contaminants. During this process, a high-acid (5-7M), low-activity stream is produced that presently is concentrated by evaporation, then cemented for long-term disposal. Our goal is to remove and concentrate the radioactive elements so that the remainder can be treated as low-level'' or regular industrial waste. Solvent extraction with neutral bifunctional extractants, such as DHDECMP and CMPO, has been chosen as the process to be developed. Experimental work has shown that both extractants effectively remove actinides to below the required limits, but that CMPO was much more difficult to strip. In addition, studies of plutonium and americium removal using a wide variety of ion exchangers and supported extractants including DHDECMP, CMPO, and TOPO will be reviewed. 22 refs., 10 figs., 3 tabs.
Date: January 1, 1990
Creator: Muscatello, A. C.; Yarbro, S .L. & Marsh, S. F.
Partner: UNT Libraries Government Documents Department

Determination of total and isotopic uranium by inductively coupled plasma-mass spectrometry at the Fernald Environmental Management Project

Description: At the Fernald Environmental Management Project (FEMP) in southwestern Ohio, ICP-mass spectrometry (ICP-MS), with sample introduction by peristaltic pumping, is used to determine total and isotopic uranium (U-234, U-235, U-236 and U-238) in soil samples. These analyses are conducted in support of the environmental cleanup of the FEMP site. Various aspects of the sample preparation and instrumental analysis will be discussed. Initial sample preparation consists of oven drying to determine moisture content, and grinding and rolling to homogenize the sample. This is followed by a nitric/hydrofluoric acid digestion to bring the uranium in the sample into solution. Bismuth is added to the sample prior to digestion to monitor for losses. The total uranium (U-238) content of this solution and the U{sup 235}/U{sup 238} ratio are measured on the first pass through the ICP-MS. To determine the concentration of the less abundant U{sup 234} and U{sup 236} isotopes, the digestate is further concentrated by using Eichrom TRU-Spec extraction columns before the second pass through the ICP-MS. Quality controls for both the sample preparation and instrumental protocols will also be discussed. Finally, an explanation of the calculations used to report the data in either weight percent or activity units will be given.
Date: April 1, 1995
Creator: Miller, F.L.; Bolin, R.N.; Feller, M.T. & Danahy, R.J.
Partner: UNT Libraries Government Documents Department

Evaluation and selection of aqueous-based technology for partitioning radionuclides from ICPP calcine

Description: Early in 1993 Westinghouse Idaho Nuclear Company (WINCO) chartered a Panel of Nuclear Separations Experts. The purpose of this Panel was to assist WINCO scientists and engineers in selecting, evaluating, and ranking candidate aqueous-based processes and technologies for potential use in partitioning selected radionuclides from nitric acid solutions of retrieved Idaho Chemical Processing Plant (ICPP) calcine. Radionuclides of interest are all transuranium elements, {sup 90}Sr, {sup 99}Tc, {sup 129}I, and {sup 137}Cs. The six man Panel met for 4 days (February 16--19, 1993) on the campus of the Idaho State University in Pocatello, Idaho. Principal topics addressed included: Available radionuclide removal technology; applicability of separations technology and processes to ICPP calcine; and potential integrated radionuclide partitioning schemes. This report, prepared from contributions from all Panel members, presents a comprehensive account of the proceedings and significant findings of the February, 1993 meeting in Pocatello.
Date: February 1, 1993
Creator: Olson, A.L.; Schulz, W.W.; Burchfield, L.A.; Carlson, C.D.; Swanson, J.L. & Thompson, M.C.
Partner: UNT Libraries Government Documents Department

Evaluation of extraction chromatography for americium recovery

Description: Extraction, or reverse-phase partition chromatography, as used mostly for analytical separations, employs an organic solvent extractant as a stationary phase on an inert support material. This technique, which has the advantage of utilizing the versatility of solvent extraction systems with the less expensive operation of ion exchange equipment, was evaluated for a process to recover low level concentrations of americium from acidic process waste streams at Rocky Flats. The bidentate organophosphorous extractant DHDECMP (dihexyl-N, N-diethylcarbamylmethylene phosphonate) was used as the stationary phase since it was shown to effectively scavenge americium from acidic waste streams without significantly extracting impurity ions. Over 30 support materials were evaluated for DHDECMP capacity and for their ability to retain the extractant. Of the supports tested, the Amberlite XAD macroreticular sorbents were found to have the highest DHDECMP capacity. Amberlite XAD-4 beads retained the extractant significantly better than the other supports evaluated. Thus, this solvent was tested for americium breakthrough capacity and compared to the theoretical capacity.
Date: March 23, 1977
Creator: Alford, C. E. & Navratil, J. D.
Partner: UNT Libraries Government Documents Department

Evaluation of solid-based separation materials for the pretreatment of radioactive wastes

Description: Separation science will play an important role in pretreating nuclear wastes stored at various US Department of Energy Sites. The application of separation processes offers potential economic and environmental benefits with regards to remediating these sites. For example, at the Hanford Site, the sizeable volume of radioactive wastes stored in underground tanks could be partitioned into a small volume of high-level waste (HLW) and a relatively large volume of low-level waste (LLW). After waste separation, only the smaller volume of HLW would require costly vitrification and geologic disposal. Furthermore, the quality of the remaining LLW form (e.g., grout) would be improved due to the lower inventory of radionuclides present in the LLW stream. This report investigates extraction chromatography as a possible separation process for Hanford wastes.
Date: May 1, 1993
Creator: Lumetta, G. J.; Wagner, M. J.; Wester, D. W. & Morrey, J. R.
Partner: UNT Libraries Government Documents Department

Extraction chromatography of neodymium by an organophosphorous extractant supported on various polymeric resins

Description: Fifteen resins coated with dihexyl-N,N-diethylcarbamoylmethyl phosphonate (CMP) were studied for their extraction of neodymium (Nd) in 4.0 and 7.0 M nitric acid. Resin properties, such as chemical composition and physical morphology, which can influence Nd extraction as well as subsequent resin regeneration (Nd stripping), were identified. Hydrophilic or polar resins coated with CMP efficiently extracted the Nd. Resins initially washed free of residual monomer and solvent before CMP coating outperformed their untreated counterparts. The macroporous styrene-divinylbenzene hydrophobic resins that were high in surface area were less effective supports compared with hydrophilic microporous Aurorez, polybenzimidazole (PBI) and macroporous Amberlite polyacrylic resins. Only one resin, Duolite C-467, showed no measurable improvement in Nd extraction with CMP coating. CMP-coated Aurorez PBI, a microporous and hydrophilic polymeric resin with an average surface area, showed the best overall efficiency for Nd removal and resin regeneration.
Date: April 1, 1993
Creator: Takigawa, D. Y.
Partner: UNT Libraries Government Documents Department

Extraction chromatography: Progress and opportunities

Description: Extraction chromatography provides a simple and effective method for the analytical and preparative-scale separation of a variety of metal ions. Recent advances in extractant design, particularly the development of extractants capable of metal ion recognition or of strong complex formation in highly acidic media, have significantly improved the utility of the technique. Advances in support design, most notably the introduction of functionalized supports to enhance metal ion retention, promise to yield further improvements. Column instability remains a significant obstacle, however, to the process-scale application of extraction chromatography. 79 refs.
Date: October 1, 1997
Creator: Dietz, M.L.; Horwitz, E.P. & Bond, A.H.
Partner: UNT Libraries Government Documents Department

Feasibility study of plutonium and uranium measurements in input dissolver solutions

Description: We are studying the isotope dilution gamma-ray spectrometry (IDGS) technique for the simultaneous measurements of concentrations and isotopic compositions for both plutonium and uranium in spent-fuel dissolver solutions at a reprocessing plant. Previous experiments have demonstrated that the IDGS technique can determine the elemental concentrations and isotopic compositions of plutonium in dissolver solutions. The chemical separation and recovery methods for just plutonium were ion-exchange techniques using anion exchange resin beads and filter papers. To keep both plutonium and uranium in the sample for simultaneous measurements, a new sample preparation method is being studied and developed: extraction chromatography. The technique uses U/TEVA{center_dot}Spec resin to separate fission products and recover both uranium and plutonium in the resin from dissolver solutions for measurements by high-resolution gamma-ray spectrometry.
Date: October 1, 1995
Creator: Li, T.K.; Kitagawa, O.; Kuno, Y. & Kurosawa, A.
Partner: UNT Libraries Government Documents Department

Improved accountability method for measuring enriched uranium in H-Canyon dissolver solution at the Savannah River Site

Description: At the Savannah River Site (SRS), accountability measurement of enriched uranium dissolved in H-Canyon is performed using isotope dilution mass spectrometry (IDMS). In the IDMS analytical method, a known quantity of uranium{sup 233} is added to the sample solution containing enriched uranium and fission products. The resulting uranium mixture must first be purified using a separation technique in the shielded analytical(``hot``) cells to lower radioactivity levels by removing fission products. Following this purification, the sample is analyzed by mass spectrometry to determine the total uranium content and isotopic abundance. The magnitude of the response of each uranium isotope in the sample solution and the response of the U{sup 233} spike is measured. By ratioing these responses, relative to the known quantity of the U{sup 233} spike, the uranium content can be determined. A hexane solvent extraction technique, used for years at SRS to remove fission products prior to the mass spectrometry analysis of uranium, has several problems. The hexone method is tedious, requires additional sample clean-up after the purified sample is removed from the shielded cells and requires the use of Resource Conservation and Recovery Act (RCRA)-listed hazardous materials (hexone and chromium compounds). A new high speed separation method that enables a rapid removal of fission products in a shielded cells environment has been developed by the SRS Central Laboratory to replace the hexone method. The new high speed column extraction chromatography technique employs applied vacuum and columns containing tri (2-ethyl-hexyl) phosphate (TEHP) solvent coated on a small particle inert support (SM-7 Bio Beads). The new separation is rapid, user friendly, eliminates the use of the RCA-listed hazardous chemicals and reduces the amount of solid waste generated by the separation method. 2 tabs. 4 figs.
Date: August 1, 1992
Creator: Maxwell, S. L. III; Satkowski, J. & Mahannah, R. N.
Partner: UNT Libraries Government Documents Department

Improved separation techniques for the characterization of radioactive waste samples

Description: Analysts have routinely used organic solvent extractions and precipitation techniques to remove matrix constituents which interfere with the characterization of radioactive waste samples. Problems with these traditional techniques involve the production of organic waste and time consuming steps. Extraction chromatography using recently developed resins manufactured by Eichrom Industries provides accuracy comparable to traditional techniques while reducing waste and time. Three types of Eichrom resins were evaluated on samples from radioactive waste tanks at the Department of Energy`s (DOE) Oak Ridge National Laboratory (ORNL) for the analysis of the inorganic EPA target analyte elements, radioactive strontium, and radioactive technetium. Results show that extraction chromatography may be successfully applied to the characterization of DOE radioactive waste samples similar to those at ORNL, providing high efficiency, reduced waste production, and safety benefits.
Date: 1994
Creator: Meeks, A. M.; Keller, J. M.; Giaquinto, J. M. & Ross, T.
Partner: UNT Libraries Government Documents Department

Measurement of actinides and strontium-90 in high activity waste

Description: The reliable measurement of trace radionuclides in high activity waste is important to support waste processing activities at SRS (F and H Area Waste Tanks, Extended Sludge Processing (ESP) and In-Tank precipitation (ITP) processing). Separation techniques are needed to remove high levels of gamma activity and alpha/beta interferences prior to analytical measurement. Using new extraction chromatographic resins from EiChrom Industries, Inc., the SRS Central Laboratory has developed new high speed separation methods that enable measurement of neptunium, thorium, uranium, plutonium, americium and strontium-90 in high activity waste solutions. Small particle size resin and applied vacuum are used to reduce analysis times and enhance column performance. Extraction chromatographic resins are easy to use and eliminate the generation of contaminated liquid organic waste.
Date: August 1, 1994
Creator: Maxwell, S. L. III & Nelson, M. R.
Partner: UNT Libraries Government Documents Department