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Technetium Behavior and Recovery in Soil

Description: Technetium-99 in soils is of great concern because of its long half-life and because it can not be detected readily. This work reviews the behavior of technetium in various types of soils. A method for extracting technetium from soil was developed with the use of technetium-95m and 99m to determine recoveries at each step. Technetium chemistry is very complicated and problem areas in the behavior and recovery have been highlighted. Technetium is widely used in nuclear medicine and a review of i… more
Date: December 1, 1995
Creator: Meinken, G. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of uranium contaminated soils from DOE Fernald Environmental Management Project Site: Results of Phase 1 characterization

Description: The Integrated Demonstration (ID) for remediation of uranium- contaminated soils has been established by the DOE Office of Technology Development. The Fernald (Feed Materials Production Center) site was selected as the DOE facility for the field demonstration. The principle objective of this ID is to evaluate and compare the versatility, efficiency, and economics of various technologies that may be combined into systems for the removal of uranium from contaminated soils. Several leaching soluti… more
Date: January 1, 1992
Creator: Lee, S. Y. & Marsh, J. D. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Isocitrate lyase and the glyoxylate cycle. Progress report, February 16, 1992--February 15, 1993

Description: This progress report describes efforts directed at the active-site modification of isocitrate lyase (icl) of Escherichia coli. Studies are reported that describe the results of several amino acid substitutions gained by directed mutagenesis of the icl gene. Preliminary studies are also related in cloning, sequencing and expression of icl of watermelon.
Date: December 31, 1992
Creator: McFadden, B. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Selective leaching of uranium from uranium-contaminated soils: Progress report 1

Description: Three soils and a sediment contaminated with uranium were used to determine the effectiveness of sodium carbonate and citric acid leaching to decontaminated or remove uranium to acceptable regulatory levels. Two of the soils were surface soils from the DOE facility formerly called the Feed Materials Production Center (FMPC) at Fernald, Ohio. This facility is presently called the Femald Environmental Management Project (FEMP). Carbonate extractions generally removed from 70 to 90% of the uranium… more
Date: February 1, 1993
Creator: Francis, C. W.; Mattus, A. J.; Farr, L. L.; Elless, M. P. & Lee, S. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of uranium contaminated soils from DOE Fernald Environmental Management Project Site: Results of Phase 1 characterization

Description: The Integrated Demonstration (ID) for remediation of uranium- contaminated soils has been established by the DOE Office of Technology Development. The Fernald (Feed Materials Production Center) site was selected as the DOE facility for the field demonstration. The principle objective of this ID is to evaluate and compare the versatility, efficiency, and economics of various technologies that may be combined into systems for the removal of uranium from contaminated soils. Several leaching soluti… more
Date: January 1, 1992
Creator: Lee, S. Y. & Marsh, J. D. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Pilot-scale decontamination solution test results HGTP-93-0702-02

Description: Decontamination solution testing constitutes a task of the Hanford Grout Technology Program (HGTP) at Pacific Northwest Laboratory (PNL). The HGTP provides technical support to the Westinghouse Hanford Company (WHC) Grout Disposal Program. Cementitious grout has been identified as the waste form for low-level radioactive waste. Grout processing equipment, including mixers, pumps, and piping, will require periodic maintenance. Decontamination of components is needed to reduce radiation dose to m… more
Date: May 1, 1993
Creator: Clemmer, R. G.; Allen, R. P.; Bagaasen, L. M. & Fetrow, L. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of citric acid demineralization on heats of immersion of Wyodak and Illinois No. 6 coals in strong acids. Tenth quarterly report

Description: An important component of our last report was the discovery that demineralization of Argonne Wyodak coal by citric acid washing had changed the heats of immersion of this coal in seven strong acids very significantly. The results were so dramatic that the whole series of experiments with this demineralized coal was repeated and confirmed. Several of the {Delta}H{sub imm}s were reduced as much as 30% while those with arylsulfonic acids actually increased. The mineral content of coals can be as h… more
Date: September 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of citric acid demineralization on heats of immersion of Wyodak and Illinois No. 6 coals in strong acids

Description: An important component of our last report was the discovery that demineralization of Argonne Wyodak coal by citric acid washing had changed the heats of immersion of this coal in seven strong acids very significantly. The results were so dramatic that the whole series of experiments with this demineralized coal was repeated and confirmed. Several of the {Delta}H{sub imm}s were reduced as much as 30% while those with arylsulfonic acids actually increased. The mineral content of coals can be as h… more
Date: January 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Bioremediation of soils, sludges, and materials contaminated with toxic metals or radionuclides

Description: Bioremediation stabilizes and reclaims radionuclide or toxic metal-contaminated materials, soils, sediments, or wastes; it then recovers the contaminating radionuclides and metals. Waste materials are stabilized and reduced in volume using anaerobic bacteria; or alternatively, materials are treated with citric acid before bioremediation begins. Photolysis is used after bioremediation to release radionuclides.
Date: April 1, 1993
Creator: Francis, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Selective leaching of uranium from uranium-contaminated soils: Progress report 1

Description: Three soils and a sediment contaminated with uranium were used to determine the effectiveness of sodium carbonate and citric acid leaching to decontaminated or remove uranium to acceptable regulatory levels. Two of the soils were surface soils from the DOE facility formerly called the Feed Materials Production Center (FMPC) at Fernald, Ohio. This facility is presently called the Femald Environmental Management Project (FEMP). Carbonate extractions generally removed from 70 to 90% of the uranium… more
Date: February 1, 1993
Creator: Francis, C. W.; Mattus, A. J.; Farr, L. L.; Elless, M. P. & Lee, S. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Decontamination solution development studies

Description: This study was conducted for the Westinghouse Hanford Company (WHC) by Pacific Northwest Laboratory (PNL) as part of the Hanford Grout Technology Program (HGTP). The objective of this study was to identify decontamination solutions capable of removing radioactive contaminants and grout from the Grout Treatment Facility (GTF) process equipment and to determine the impact of these solutions on equipment components and disposal options. The reference grout used in this study was prepared with simu… more
Date: September 1, 1993
Creator: Allen, R. P.; Fetrow, L. K.; Kjarmo, H. E. & Pool, K. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Remediation of heavy-metal-contaminated soil using chelant extraction: Feasibility studies

Description: Results are presented of a laboratory investigation conducted to determine the efficacy of using chelating agents to extract heavy metals (Pb, Cd, Cr, Ba, Cu, and Zn) from soil, the primary focus being on the extraction of lead from the soil. Results from the batch-shaker studies and emphasizes the columnar extraction studies are described. The chelating agents studied included ethylenediaminetetraacetic acid (EDTA) and citric acid, in addition to water. Concentrations of the chelants ranged fr… more
Date: August 1, 1993
Creator: Peters, R. W.; Miller, G.; Taylor, J. D.; Schneider, J. F.; Zellmer, S.; Edgar, D. E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Detection of decontamination solution chelating agents using ion selective coated-wire electrodes

Description: This thesis explores feasibility of using coated-wire electrodes to measure chelating agent concentration. Chelating agents are often found in radioactive decontamination solutions because they aid in the removal of radionuclides from contaminated surfaces by increasing their solubility. However, this characteristic will also enhance the mobility of the radionuclide and thus its transport out of a waste disposal site. Coated-wire ion selective electrodes, based on a polyvinylchloride membrane u… more
Date: 1992
Creator: Banks, Mark Lavior
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Removal and recovery of radionuclides and toxic metals from wastes, soils and materials

Description: A process has been developed at Brookhaven National Laboratory (BNL) for the removal of metals and radionuclides from contaminated materials, soils, and waste sites (Figure 1). In this process, citric acid, a naturally occurring organic complexing agent, is used to extract metals such as Ba, Cd, Cr, Ni, Zn, and radionuclides Co, Sr, Th, and U from solid wastes by formation of water soluble, metal-citrate complexes. Citric acid forms different types of complexes with the transition metals and ac… more
Date: July 1, 1993
Creator: Francis, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Water-enhanced solvation of organics

Description: Water-enhanced solvation (WES) was explored for Lewis acid solutes in Lewis base organic solvents, to develop cheap extract regeneration processes. WES for solid solutes was determined from ratios of solubilities of solutes in water-sat. and low-water solvent; both were determined from solid-liquid equilibrium. Vapor-headspace analysis was used to determine solute activity coefficients as function of organic phase water concentration. WES magnitudes of volatile solutes were normalized, set equa… more
Date: July 1, 1993
Creator: Lee, J. H.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Variation of stability constants of thorium citrate complexes and of thorium hydrolysis constants with ionic strength

Description: Citrate is among the organic anions that are expected to be present in the wastes planned for deposition in the Waste Isolation Pilot Plant repository. In this study, a solvent extraction method has been used to measure the stability constants of Thorium(IV)[Th(IV)] with citrate anions in aqueous solutions with (a) NaClO{sub 4} and (b) NaCl as the background electrolytes. The ionic strengths were varied up to 5 m (NaCl) and 14 m (NaClO{sub 4}). The data from the NaClO{sub 4} solutions at varyin… more
Date: September 1, 1995
Creator: Choppin, Gregory R.; Erten, Hasan N. & Xia, Yuan-Xian
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Bioremediation of Uranium Contaminated Soils and Wastes.

Description: Contamination of soils, water, and sediments by radionuclides and toxic metals from uranium mill tailings, nuclear fuel manufacturing and nuclear weapons production is a major concern. Studies of the mechanisms of biotransformation of uranium and toxic metals under various microbial process conditions has resulted in the development of two treatment processes: (i) stabilization of uranium and toxic metals with reduction in waste volume and (ii) removal and recovery of uranium and toxic metals f… more
Date: September 17, 1998
Creator: Francis, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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BNL Citric Acid Technology: Pilot Scale Demonstration

Description: The objective of this project is to remove toxic metals such as lead and cadmium from incinerator ash using the Citric Acid Process developed at Brookhaven National Laboratory. In this process toxic metals in bottom ash from the incineration of municipal solid waste were first extracted with citric acid followed by biodegradation of the citric acid-metal extract by the bacterium Pseudomonas fluorescens for metals recovery. The ash contained the following metals: Al, As, Ba, Ca, Cd, Cr, Cu, Fe, … more
Date: September 24, 1999
Creator: Francis, A. J.; Dodge; J, C; Gillow, J. B. & Forrester, K. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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