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Boron reclamation

Description: A process to recover high purity /sup 10/B enriched crystalline boron powder from a polymeric matrix was developed on a laboratory basis and ultimately scaled up to production capacity. The process is based on controlled pyrolysis of boron-filled scrap followed by an acid leach and dry sieving operation to return the powder to the required purity and particle size specifications. Typically, the recovery rate of the crystalline powder is in excess of 98.5 percent, and some of the remaining boron… more
Date: July 1, 1980
Creator: Smith, R. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electrochemistry of Thiobacillus ferrooxidans reactions with pyrite

Description: The objective of this project is to provide the fundamental information on the mechanisms of bacterial leaching of pyrite. The knowledge of how bacterial leaching of pyrite functions is essential for design and development of a technology for coal cleaning with bacteria. The features of major electrochemical techniques will be examined to find out if any of them can provide a diagnostic information on the mechanisms of related reactions.
Date: January 1, 1992
Creator: Pesic, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alkali sorber (RABSAM), September 1, 1990--August 30, 1991

Description: The objective of this work is to develop a regenerable activated-bauxite sorber alkali monitor that requires no high-temperature/high-pressure sampling line for the reliable in situ measurement of alkali-vapor concentration in the exhaust from the pressurized fluidized-bed combustion of coal. 11 refs., 2 figs., 1 tab.
Date: January 1, 1991
Creator: Lee, S. H. D. & Swift, M. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Long-term leaching of irradiated spent fuel

Description: Spent Light Water Reactor (LWR) fuel with burnups of 9, 28 and 54 MWd/kg U were leach tested at 25/sup 0/C in deionized water in a Paige apparatus. No discernible differences in leach rates were observed due to burnup. Additionally, the 28 MWd/kg U fuel was IAEA leach tested in five different leachants using the IAEA method. Deionized water gave the highest leach rates and a calcium chloride solution gave the lowest leach rates. An accelerated leaching period was observed during the Paige leach… more
Date: January 1, 1979
Creator: Katayama, Y. B. & Bradley, D. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tritium storage development. Progress report No. 12, April--June 1977. [In metal hydride; polymer impregnated tritiated concrete]

Description: Laboratory work was continued on hydriding of zirconium sponge and rod under varying conditions of temperature (400 to 900/sup 0/C) and pressure (0-1000 torr) to determine optimum conditions for the formation of hydrides with desirable mechanical properties. Titanium sponge and rod were also hydrided for comparison. Zirconium and titanium samples containing tritium were prepared and initial leach data were obtained. Leach rates for zirconium in distilled water ranged from 1.1 x 10/sup -6/ to 4.… more
Date: January 1, 1976
Creator: Colombo, P
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Role of groundwater oxidation potential and radiolysis on waste glass performance in crystalline repository environments

Description: Laboratory experiments have shown that groundwater conditions in a Stripa granite repository will be as reducing as those in a basalt repository. The final oxidation potential (Eh) at 70/sup 0/C for Stripa groundwater deaerated and equilibrated with crystalline granite was -0.45V. In contrast, the oxidation potential at 60/sup 0/C for Grande Ronde groundwater equilibrated with basalt was -0.40V. The reducing groundwater conditions were found to slightly decrease the time-dependent release of so… more
Date: January 1, 1985
Creator: Jantzen, Carol M. & Bibler, Ned E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Leaching studies of low-level radioactive waste forms

Description: A research program has been under way at the Brookhaven National Laboratory to investigate the radionuclide release behavior of ion exchange bead resin waste solidified in Portland cement. An important aspect of this program is to develop and evaluate testing procedures and methodologies which enable the long-term performance evaluation of waste forms under simulated field conditions. Cesium and strontium release behavior using a range of testing procedures, including intermittent leachant flow… more
Date: January 1, 1985
Creator: Dayal, R.; Arora, H.; Clinton, J.C. & Milian, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The product consistency test for the DWPF wasteform

Description: The preliminary specifications on the glass wasteform to be produced by the Defense Waste Processing Facility (DWPF) require extensive characterization of the glass product both before actual production begins and then during production. To aid in this characterization, a leach test was needed that was easily reproducible, could be performed remotely on highly radioactive samples, and could yield results rapidly. Several standard leach tests were examined with a variety of test configurations. … more
Date: January 1, 1990
Creator: Jantzen, Carol M. & Bibler, N. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design requirements for uranium ion exchange from acidic solutions in a fluidized system

Description: A fluidized, countercurrent ion-exchange system was developed, operated, and evaluated by the Bureau of Mines in support of its objective to help assure an adequate uranium supply for future national needs. The system consisted of integrated multiple-compartment absorption and elution columns in which the solution flows are continuous, except for short periods when resin increments are withdrawn. The exchange of uranyl sulfate between a simulated acid-leach-uranium solution and a strong-base, i… more
Date: January 1, 1974
Creator: Traut, D.E.; Nichols, I.L. & Seidel, D.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Biological solutions to waste management

Description: The purpose of this program is to develop low-cost processes for the removal of toxic metals from geothermal residual brines. Processes and methodologies are also being developed for the utilization of detoxified residues. Laboratory work at Brookhaven National Laboratory (BNL) has shown that bioleaching is an efficient method for the removal of toxic metals from residual brine sludges. Samples of geothermal brine residues, supplied by the industry, containing elevated concentrations of heavy m… more
Date: January 1, 1988
Creator: Premuzic, E. T.; Lin, Mow & Kukacka, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Evaluation of filter media for clarification of partially dissolved residues containing plutonium

Description: A common process in the chemical industry employs the leaching of a desirable component from an insoluble substrate, followed by filtration to produce a clarified solution of the desirable component and a discardable residue. The work described here involved evaluating sintered metal filter media for separating dissolved plutonium from undissolved residues generated at various locations owned by the Department of Energy throughout the United States. The work was performed during a six-week assi… more
Date: October 9, 1989
Creator: Foley, E.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ion-beam depth-profiling studies of leached glasses

Description: Ion-beam depth-profiling was carried out on three different glasses leached (or hydrated) in deionized water using /sup 1/H(/sup 19/F,..cap alpha gamma..)/sup 16/O nuclear reaction, secondary ion mass spectrometry (SIMS) and sputter-induced photon spectrometry (SIPS) techniques. The depth-profiles show an interdiffusion mechanism in which the sodium ions in the glass are depleted and replaced by hydrogen (H/sup +/) or hydronium (H/sub 3/O/sup +/) ions from the solution. The leaching behavior do… more
Date: January 1, 1981
Creator: Houser, C. A.; Tsong, I. S. T.; White, W. B.; Wintenberg, A. L.; Miller, P. D. & Moak, C. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tritium storage development. Progress report No. 13, July--September 1977

Description: Engineering-scale operation was started on hydriding of zirconium for application to tritium storage systems. Eight runs were made with commercial-grade zirconium sponge at 338/sup 0/ to 499/sup 0/C and 0 to 770 torr, hydrided to hydrogen-to-zirconium atom ratios up to 2. Reaction rates were determined for hydrogen flow rates of 2.72 to 9.24 cm/sup 3/ at STP/g Zr-min. For each run, hydrogen pressure was plotted on a semilog scale against time and H/Zr atom ratio to elucidate the reaction mechan… more
Date: January 1, 1977
Creator: Colombo, P. & Johnson, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Nuclear waste-form risk assessment for US Defense waste at Savannah River Plant. Annual report FY 1981

Description: Savannah River Plant has been supporting the Lawrence Livermore National Laboratory in its present effort to perform risk assessments of alternative waste forms for defense waste. This effort relates to choosing a suitable combination of solid form and geologic medium on the basis of risk of exposure to future generations; therefore, the focus is on post-closure considerations of deep geologic repositories. The waste forms being investigated include borosilicate glass, SYNROC, and others. Geolo… more
Date: December 1, 1981
Creator: Cheung, H.; Edwards, L. L.; Harvey, T. F.; Jackson, D. D. & Revelli, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of glass formulations containing high-level nuclear wastes

Description: The effects of Na/sub 2/O, K/sub 2/O, B/sub 2/O/sub 3/, TiO/sub 2/, CaO, and ZnO contents were determined on the leach rate and homogeneity of a potential high-level waste glass. It was found that the two characteristics are in competition, with variations of CaO having the greatest effect and TiO/sub 2/ having the least effect. Boron oxide content is important in control of Na/sub 2/MoO/sub 4/ formation and separation. Sodium molybdate formation can also be controlled by the use of reducing ag… more
Date: February 1, 1978
Creator: Ross, W.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Advances in materials science, Metals and Ceramics Division. Triannual progress report, February-May 1980

Description: Research is reported in the magnetic fusion energy and laser fusion energy programs, aluminium-air battery and vehicle research, geothermal research, nuclear waste management, basic energy science, and chemistry and materials science. (FS)
Date: August 1, 1980
Creator: Truhan, J.J. & Gordon, K.M. (eds.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Relative availability of selected trace elements from coal fly ash and Lake Michigan sediment

Description: The concentration of greater than 1 ..mu..m coal fly ash particles in Lake Michigan surface waters was found to be 10/sup 5/ to 10/sup 6/ per liter. With an expected residence time of one year, this concentration implies a flux to the sediment of 10/sup 6/ to 10/sup 7/ particles/cm/sup 2//yr, or about 10/sup -6/ to 10/sup -5/ g/cm/sup 2//yr. The release of trace elements from fly ash and sediment has been studied using Chelex-100 resin to simulate leaching at high dilutions in natural media. Mn… more
Date: January 1, 1977
Creator: Alberts, J.J.; Burger, J.; Kalhorn, S.; Seils, C. & Tisue, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Prediction of the migration of radionuclides to the boundary of a shallow land burial trench

Description: A general model which predicts the source term, radionuclide release rate, as a function of water flow, container degradation rate, waste form leach rate, and radionuclide migration rate from a low-level waste shallow land burial treach is being developed. This paper discusses modeling radionuclide migration, one component of the source term. Simulations of radionuclide transport from a generic shallow land burial trench have been performed for a range of water flow rates, dispersivity values, … more
Date: January 1, 1988
Creator: Sullivan, T.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Properties of radioactive wastes and waste containers. Quarterly progress report, April-June 1980

Description: A study was initiated to determine the effect of varying V/S (the ratio of the waste form volume to its surface area) on the leachability of radioisotopes incorported in cement forms. Cesium-137 and strontium-85 mixed with a simulated formulation of waste derived from forced recirculation evaporator bottoms of LWR's were solidified in portland II cement. The V/S ratios of the forms varied from 0.41 to 2.77. The resulting forms were leached using a modified IAEA procedure. Leaching data indicate… more
Date: August 1, 1980
Creator: Morcos, N. & Weiss, A.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research and development activities Waste Fixation Program. Quarterly progress report, January--March 1977

Description: Research and Development activities of the Waste Fixation Program for January through March 1977 are described in this report. The objective of this program is to develop processes to convert high-level radioactive liquid waste (HLLW) to solid forms that are demonstrated to be physically, chemically, and radiolytically stable and inert. Several significant results were obtained during this reporting period.
Date: November 1, 1977
Creator: McElroy, J.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recovery of plutonium from HEPA filters by Ce(IV): promoted dissolution of PuO/sub 2/ and recycle of the cerium promoter

Description: Studies carried out in this investigation included (1) electrolytic production of Ce(IV) from Ce(III), (2) leaching of refractory PuO/sub 2/ from HEPA filters with maintenance of Ce(IV) by anodic oxidation during leaching, and (3) evaluation of methods for contacting the HEPA solids with the leaching solution and for separating the solid residue from the leaching liquor. Anodic oxidation of Ce(III) was accomplished with an electric current efficiency of about 85% at current densities of 0.04 to… more
Date: May 1, 1980
Creator: Scheitlin, F.M. & Bond, W.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solidification/stabilization of technetium in cement-based grouts

Description: Mixed low-level radioactive and chemically hazardous process treatment wastes from the Portsmouth Gaseous Diffusion Plant are stabilized by solidification in cement-based grouts. Conventional portland cement and fly ash grouts have been shown to be effective for retention of hydrolyzable metals (e.g., lead, cadmium, uranium and nickel) but are marginally acceptable for retention of radioactive Tc-99, which is present in the waste as the highly mobile pertechnate anion. Addition of ground blast … more
Date: January 1, 1990
Creator: Gilliam, T. M.; Bostick, W. D.; Spence, R. D.; Shoemaker, J. L. (Oak Ridge National Lab., TN (USA); Oak Ridge Gaseous Diffusion Plant, TN (USA); Oak Ridge National Lab., TN (USA) et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sequential purification and crystal growth for the production of low cost silicon substrates. Quarterly technical progress report No. 1, 15 September 1979-31 December 1979

Description: Over the past several years, Motorola's Materials Technology Laboratory (MTL), has been conducting several projects with goals directed at the production of high quality low cost silicon crystals. One of the projects which is being investigated is the direct purification of MG-Si. A unique characteristic of the approach used by this project is the use of a crystal puller to perform both purification and crystal growth. Sequential steps of purification were taken. By the completion of this … more
Date: February 1, 1980
Creator: Liaw, M.; Secco, F.; Ingle, B. & Down, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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