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Sample records for plutonium extraction radiolysis

  1. The use tri-n-butyl phosphate in plutonium extraction. Radiolysis and recycling of the solvent (1963); Le phosphate de tri-n-butyle dans l'extraction du plutonium. Radiolyse et recyclage du solvant (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Isaac, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-07-01

    The work concerns the radiolysis and recycling of tri-n-butyl phosphate used as extraction solvent for plutonium. The radiolysis is studied on an industrial solvent using a cobalt 60 source. Figures are given for the yield of the mono- and di-butyl-phosphoric acids formed from the dry and water-saturated solvents and the influence of nitric acid on the formation of dibutyl-phosphoric acid is indicated. The recycling treatment of the solvent is reconsidered with a view to lowering the residual contamination due to fission products. The tests carried out on a solvent from the plutonium extraction plant at Marcoule show the efficiency of the sodium carbonate treatment. Of all the products studied, only caustic soda led to a better decontamination than sodium carbonate; in all cases however, the elimination of ruthenium is always incomplete. (author) [French] L'etude porte sur la radiolyse et le recyclage du phosphate de tri-n-butyle utilise comme solvant d'extraction du plutonium. La radiolyse est etudiee sur un solvant industriel a l'aide d'une source de cobalt 60. On donne les rendements de formation des acides mono- et dlbutylphosphoriques a partir de solvants secs et satures d'eau, et on montre l'influence de l'acide nitrique sur la formation de l'acide dibutylphosphorique. Le traitement de recyclage du solvant est repris en vue d'abaisser la contamination residuelle en produits de fission. Les essais, effectues sur un solvant provenant de l'usine d'extraction du plutonium de Marcoule, montrent l'efficacite du traitement au carbonate de sodium. De tous les reactifs etudies, seule la soude a donne une decontamination superieure au carbonate de sodium; mais dans tous les cas, l'elimination du ruthenium est toujours incomplete. (auteur)

  2. Radiolysis of aqueous solution of plutonium; Radiolyse des solutions aqueuses de plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Pages nee Flon, M [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1960-07-01

    This study is concerned first with the effects of gamma rays on plutonium aqueous solutions at various valency states, in presence of sulfuric, perchloric, nitric and hydrochloric acids. The main feature is the reduction of Pu VI into Pu V, followed by dismutation from V to IV and VI. For sulfuric and perchloric acid solutions (0,2 N) the following process is given: radiolysis of water produces OH, H{sub 2}O{sub 2}, H and H{sub 2}. H and H{sub 2}O{sub 2} reduce Pu VI while Pu V is oxidised by OH radicals. However the reaction of hydrogen peroxide is slow and leads to an after effect. A parallel study of the action of H{sub 2}O{sub 2} has given a confirmation. Spectrophotometric measurements were carried out on disappearance of Pu VI and formation of Pu IV and it was possible to make determination of G{sub H{sub 2}}{sub O{sub 2}} = 0,8 and G{sub H} - G{sub OH} = 0,8. G{sub H{sub 2}} = 0,41 was measured by gas analysis. The calculation of G{sub {sup -}}{sub H{sub 2}}{sub O} gave 4,35. The re-oxidation of Pu V is dependant on the concentration of sulfate ions. In perchloric acid solution reduction goes on to Pu Ill. Cl{sup -} and NO{sub 3}{sup -} ions inhibit the reduction and even suppress it. The effect of alpha particles both from plutonium and from polonium is very similar to the effect of hydrogen peroxyde. Induction time were observed mainly in presence of HSO{sub 4}{sup -}, depending on the accumulation of H{sub 2}O{sub 2} and (or) of plutonium peroxide. At low acidities, Pu IV peroxide seems to lead to polymer forms. In the more simple cases (H{sub 2}SO{sub 4} and HClO{sub 4} 0,2N), the following yields were found: G (equivalent reduced) = 3.2, G{sub H{sub 2}}{sub O{sub 2}} = 1.35, G{sub H{sub 2}} = 1.6 and G{sub H} - G{sub OH} = 0.1, assuming G{sub HO{sub 2}} = 0.2; and the usual hypothesis on radiolysis of water by alpha particles. Radiation induced oxidation of Pu III into Pu IV was also observed in H{sub 2}SO{sub 4} and HNO{sub 3} aqueous solutions, and

  3. Corrosive gas generation potential from chloride salt radiolysis in plutonium environments

    International Nuclear Information System (INIS)

    Tandon, L.; Allen, T.H.; Mason, R.E.; Penneman, R.A.

    1999-01-01

    The specific goal of this project was to evaluate the magnitude and practical significance of radiation effects involving mixtures of chloride salts and plutonium dioxide (PuO 2 ) sealed in stainless steel containers and stored for up to 50 yr, after stabilization at 950 C and packaging according to US Department of Energy (DOE) standards. The potential for generating chemically aggressive molecular chlorine (and hydrogen chloride by interaction with adsorbed water or hydrogen gas) by radiolysis of chloride ions was studied. To evaluate the risks, an annotated bibliography on chloride salt radiolysis was created with emphasis on effects of plutonium alpha radiation. The authors present data from the material identification and surveillance (MIS) project obtained from examination and analysis of representative PuO 2 items from various DOE sites, including the headspace gas analysis data of sealed mixtures of PuO 2 and chloride salts following long-term storage

  4. EVIDENCE OF CORROSIVE GAS FORMED BY RADIOLYSIS OF CHLORIDE SALTS IN PLUTONIUM-BEARING MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, K.; Louthan, M.

    2010-02-01

    Corrosion and pitting have been observed in headspace regions of stainless steel containers enclosing plutonium oxide/salt mixtures. These observations are consistent with the formation of a corrosive gas, probably HCl, and transport of that gas to the headspace regions of sealed containers. The NH{sub 4}Cl films found on the walls of the sealed containers is also indicative of the presence of HCl gas. Radiolysis of hydrated alkaline earth salts is the probable source of HCl.

  5. Gamma radiolysis of alkaline aqueous solutions of neptunium and plutonium ions

    International Nuclear Information System (INIS)

    Pikaev, A.K.; Gogolev, A.V.; Shilov, V.P.

    1998-01-01

    Full text: The paper is a brief review of data obtained by the authors from the study on redox reactions of neptunium and plutonium ions upon γ radiolysis of their aerated alkaline aqueous solutions. It includes the information on radiolytic reduction of Np(V), Np(VI) and Pu(VI) ions under various experimental conditions. It was found that the values of Np(VI) and Pu(VI) reduction yields do not depend on alkali concentration. The values considerably increase in the presence of some organic compounds (EDTA and formate were investigated). The formation of the Np(V) peroxo complex was observed in the γ radiolysis of alkaline aqueous solutions of Np(VI) and Np(V) in the presence of nitrate. The mechanism of radiolytic redox reactions of the ions is discussed in some detail

  6. Study of the influence of radiolysis on the stability of plutonium III. Application to a heterogeneous medium formed by a nitric solution of ferrous ions and an organic solution of trilauryl-ammonium nitrate

    International Nuclear Information System (INIS)

    Fourmaux, J.M.

    1980-01-01

    The objective of this research thesis is to study the behaviour of plutonium 238 in media which are commonly used to isolate it from other elements such as neptunium and fission products created during the neutron irradiation of the neptunium 237 isotope. As plutonium 238 purification processes are all based on redox reaction, it is essential to know the influence of radiolysis on the redox behaviour, and on the distribution coefficients of this isotope in solutions used during its separation from the neptunium 237 isotope. Therefore, it is necessary to study the influence of radiolysis on the stability of plutonium with an oxidation III level. As this extraction is performed by an organic solvent (trilauryl-ammonium nitrate), this study addresses the behaviour of plutonium in an emulsion formed by this solvent and the nitric aqueous solution previously adjusted in terms of Fe 2+ ions. After a brief recall of bibliographical generalities related to radiolysis, the author presents and comments the Nernst law in the case of a two-phase system (emulsion), and reports the use of this law to obtain the plutonium potential-distribution coefficient relationship. The last part reports experimental data

  7. Plutonium and americium extraction studies with bifunctional organophosphorus extractants

    International Nuclear Information System (INIS)

    Navratil, J.D.

    1985-01-01

    Neutral bifunctional organophosphorus extractants, such as octylphenyl-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) and dihexyl-N,N-diethylcarbamoylmethylphosphonate (CMP), are under study at the Rocky Flats Plant (RFP) to remove plutonium and americium from the 7M nitric acid waste. These compounds extract trivalent actinides from strong nitric acid, a property which distinguishes them from monofunctional organiphosphorus reagents. Furthermore, the reagents extract hydroytic plutonium (IV) polymer which is present in the acid waste stream. The compounds extract trivalent actinides with a 3:1 stoichiometry, whereas tetra- and hexavalent actinides extract with a stoichiometry of 2:1. Preliminary studies indicate that the extracted plutonium polymer complex contains one to two molecules of CMP per plutonium ion and the plutonium(IV) maintains a polymeric structure. Recent studies by Horwitz and co-workers conclude that the CMPO and CMP reagents behave as monodentate ligands. At RFP, three techniques are being tested for using CMP and CMPO to remove plutonium and americium from nitric acid waste streams. The different techniques are liquid-liquid extraction, extraction chromatography, and solid-supported liquid membranes. Recent tests of the last two techniques will be briefly described. In all the experiments, CMP was an 84% pure material from Bray Oil Co. and CMPO was 98% pure from M and T Chemicals

  8. Study on the plutonium extraction and reextraction in radiolytic degraded system 30 % TBP-n-dodecane/HNO3-H2O

    International Nuclear Information System (INIS)

    Hoffmann, P.M.; Wronska, T.

    1980-01-01

    The degree of the complexation of plutonium(4) by the products of radiolysis of the system 30 % TBP-n-dodecane/HNO 3 -H 2 O as a function of radiation dose and concentration of nitric acid has been studied. The special method of calculation based on extraction equilibria was used. The retention of plutonium in the organic phase after single reductive reextraction has been determined. (author)

  9. The extraction of plutonium with triethylene glycol dichloride

    International Nuclear Information System (INIS)

    Aikin, A.M.; Moss, M.; Bruce, T.

    1951-03-01

    The extraction of plutonium by triethylene glycol dichloride (trigly) has been investigated briefly. The effect of (1) the valence state of the plutonium, (2) the concentration of nitric acid, (3) the concentration of ammonium nitrate and (4) the conditioning of the trigly was measured. The solubility of plutonium IV in trigly was found to be 70 mgms/ml. Solutions of plutonium in trigly and in concentrated nitric acid solutions have been examined spectrophotometrically. (author)

  10. The extraction of plutonium with triethylene glycol dichloride

    Energy Technology Data Exchange (ETDEWEB)

    Aikin, A M; Moss, M; Bruce, T

    1951-03-15

    The extraction of plutonium by triethylene glycol dichloride (trigly) has been investigated briefly. The effect of (1) the valence state of the plutonium, (2) the concentration of nitric acid, (3) the concentration of ammonium nitrate and (4) the conditioning of the trigly was measured. The solubility of plutonium IV in trigly was found to be 70 mgms/ml. Solutions of plutonium in trigly and in concentrated nitric acid solutions have been examined spectrophotometrically. (author)

  11. Test plan for demonstrating plutonium extraction from 10-L solutions using EIChrom extraction chromatographic resins

    International Nuclear Information System (INIS)

    Barney, G.S.

    1994-01-01

    Corrosive plutonium solutions stored in 10-L containers at the Plutonium Finishing Plant must be treated to convert the plutonium to a safe, solid form for storage and to remove the americium so that radiation exposure can be reduced. Extraction chromatographic resins will be tested for separating plutonium from these solutions in the laboratory. Separation parameters will be developed during the testing for large scale processing of the 10-L solutions and solutions of similar composition. Use of chromatographic resins will allow plutonium separation with minimum of chemical addition to the feed and without the need for plutonium valence adjustment. The separated plutonium will be calcined to plutonium oxide by direct solution calcination

  12. Pyrochemical investigations into recovering plutonium from americium extraction salt residues

    International Nuclear Information System (INIS)

    Fife, K.W.; West, M.H.

    1987-05-01

    Progress into developing a pyrochemical technique for separating and recovering plutonium from spent americium extraction waste salts has concentrated on selective chemical reduction with lanthanum metal and calcium metal and on the solvent extraction of americium with calcium metal. Both techniques are effective for recovering plutonium from the waste salt, although neither appears suitable as a separation technique for recycling a plutonium stream back to mainline purification processes. 17 refs., 13 figs., 2 tabs

  13. Radiolysis of Salts and Long-Term Storage Issues for Both Pure and Impure PuO{sub 2} Materials in Plutonium Storage Containers

    Energy Technology Data Exchange (ETDEWEB)

    Lav Tandon

    2000-05-01

    The Material Identification and Surveillance (MIS) project sponsored a literature search on the effects of radiation on salts, with focus on alkali chlorides. The goal of the survey was to provide a basis for estimating the magnitude of {alpha} radiation effects on alkali chlorides that can accompany plutonium oxide (PuO{sub 2}) into storage. Chloride radiolysis can yield potentially corrosive gases in plutonium storage containers that can adversely affect long-term stability. This literature search was primarily done to provide a tutorial on this topic, especially for personnel with nonradiation chemistry backgrounds.

  14. Search for plutonium salt deposits in the plutonium extraction batteries of the Marcoule plant (1963)

    International Nuclear Information System (INIS)

    Bouzigues, H.; Reneaud, J.M.

    1963-01-01

    This report describes a method and a special apparatus making it possible to detach the insoluble plutonium salt deposits in the extraction chain of an irradiated fuel treatment plant. The process chosen allows the detection, in the extraction batteries or in the highly active chemical engineering equipment, of plutonium quantities of a few grains. After four years operation it has been impossible to detect measurable quantities of plutonium in any part of the extraction chain. The results have been confirmed by visual examinations carried out with a specially constructed endoscope. (authors) [fr

  15. Supercritical Fluid Extraction of Plutonium and Americium from Soil

    International Nuclear Information System (INIS)

    Fox, R.V.; Mincher, B.J.

    2002-01-01

    Supercritical fluid extraction (SFE) of plutonium and americium from soil was successfully demonstrated using supercritical fluid carbon dioxide solvent augmented with organophosphorus and beta-diketone complexants. Spiked Idaho soils were chemically and radiologically characterized, then extracted with supercritical fluid carbon dioxide at 2,900 psi and 65 C containing varying concentrations of tributyl phosphate (TBP) and thenoyltrifluoroacetone (TTA). A single 45 minute SFE with 2.7 mol% TBP and 3.2 mol% TTA provided as much as 88% ± 6.0 extraction of americium and 69% ± 5.0 extraction of plutonium. Use of 5.3 mol% TBP with 6.8 mol% of the more acidic beta-diketone hexafluoroacetylacetone (HFA) provided 95% ± 3.0 extraction of americium and 83% ± 5.0 extraction of plutonium in a single 45 minute SFE at 3,750 psi and 95 C. Sequential chemical extraction techniques were used to chemically characterize soil partitioning of plutonium and americium in pre-SFE soil samples. Sequential chemical extraction techniques demonstrated that spiked plutonium resides primarily (76.6%) in the sesquioxide fraction with minor amounts being absorbed by the oxidizable fraction (10.6%) and residual fractions (12.8%). Post-SFE soils subjected to sequential chemical extraction characterization demonstrated that 97% of the oxidizable, 78% of the sesquioxide and 80% of the residual plutonium could be removed using SFE. These preliminary results show that SFE may be an effective solvent extraction technique for removal of actinide contaminants from soil

  16. Extraction and purification of plutonium by a tertiary amine; Extraction et purification du plutonium par une amine tertiaire

    Energy Technology Data Exchange (ETDEWEB)

    Trentinian, M de; Chesne, A [Commissariat a l' Energie Atomique, Fontenay aux Roses, Section de Chimie des Actimides (France).Centre d' Etudes Nucleaires; Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Trilaurylamine diluted with a paraffinic solvent (dodecane) was studied as part of the research dealing with the separation and purification of plutonium. The physical properties (solubility of nitrates in the amine as a function of temperature) and the resistance to radiations of this substance were examined. The extraction characteristics of nitric solutions of plutonium, uranium and certain fission products are given as a function of the following factors: concentration of the various ions in solution, valency states. A method of plutonium purification based on these results is presented. (author) [French] La trilaurylamine diluee par un solvant paraffinique (dodecane) a ete etudiee dans le cadre des recherches concernant la separation et la purification du plutonium. Une etude des caracteres physiques (solubilite des nitrates dans l'amine en fonction de la temperature) s'ajoute a celle de la tenue aux radiations de ce corps. Les caracteristiques d'extraction de solutions nitriques de plutonium, uranium, et certains produits de fission, sont donnes en fonction des facteurs suivants: concentration des differents ions en solution, etats de valence. On presente une methode de purification du plutonium basee sur ces resultats. (auteur)

  17. Radiolysis aspects of the aqueous self-cooled blanket concept and the problem of tritium extraction

    International Nuclear Information System (INIS)

    Bruggeman, A.; Snykers, M.; DeRegge, P.; Embrechts, M.J.

    1988-01-01

    In the Aqueous Self-Cooled Blanket (ASCB) concept, an aqueous 6 Li solution in a metallic structure is used as a fusion reactor shielding-breeding blanket. Radiolysis effects could be very important for the design and the use of an ASCB. Although many aspects of the radiation chemistry of water and dilute aqueous solutions are now reasonably well understood, it is not possible to predict the radiochemical behaviour of the concentrated candidate ASCB solutions quantitatively. However, by means of a worst case calculation for a possible ASCB for the Next European Torus (NET) it is shown that even with an important rate of water decomposition the ASCB concept is still workable. Gas bubbles and explosive mixtures can be avoided by increasing the pressure in the neutron irradiated zone and by extracting and/or recombining the radiolytically produced hydrogen and oxygen. This could require an additional inert gas loop, which could also be used as part of the tritium extraction installation

  18. Search for plutonium salt deposits in the plutonium extraction batteries of the Marcoule plant (1963); Recherche de depots de sels de plutonium dans les batteries d'extraction du plutonium de l'usine de Marcoule (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Bouzigues, H; Reneaud, J M [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

    1963-07-01

    This report describes a method and a special apparatus making it possible to detach the insoluble plutonium salt deposits in the extraction chain of an irradiated fuel treatment plant. The process chosen allows the detection, in the extraction batteries or in the highly active chemical engineering equipment, of plutonium quantities of a few grains. After four years operation it has been impossible to detect measurable quantities of plutonium in any part of the extraction chain. The results have been confirmed by visual examinations carried out with a specially constructed endoscope. (authors) [French] Ce rapport decrit une methode et un montage special permettant de detacher les accumulations de sels de plutonium insolubles dans les chaines d'extraction d'une usine de traitement de combustible irradie. Le procede retenu permet de reperer, dans des batteries d'extraction ou dans l'appareillage de genie chimique fortement actif, des masses de plutonium de quelques grammes. Apres quatre annees de fonctionnement, il n'a pas ete possible de deceler des quantites ponderables de plutonium en aucun endroit de la chaine d'extraction. Ces resultats ont ete confirmes par les examens visuels effectues a l'aide d'un endoscope concu specialement pour cet usage. (auteurs)

  19. Fuel Cycle Impacts of Uranium-Plutonium Co-extraction

    International Nuclear Information System (INIS)

    Taiwo, Temitope; Szakaly, Frank; Kim, Taek-Kyum; Hill, Robert

    2008-01-01

    A systematic investigation of the impacts of uranium and plutonium co-extraction during fuel separations on reactor performance and fuel cycle has been performed. Proliferation indicators, critical mass and radiation source levels of the separation products or fabricated fuel, were also evaluated. Using LWR-spent-uranium-based MOX fuel instead of natural-uranium-based fuel in a PWR MOX core requires a higher initial plutonium content (∼1%), and results in higher Np-237 content (factor of 5) in the spent fuel, and less consumption of Pu-238 (20%) and Am-241 (14%), indicating a reduction in the effective repository space utilization. Additionally, minor actinides continue to accumulate in the fuel cycle, and thus a separate solution is required for them. Differences were found to be quite smaller (∼0.4% in initial transuranics) between the equilibrium cycles of advanced fast reactor cores using spent and depleted uranium for make-up, in additional to transuranics. The critical masses of the co-extraction products were found to be higher than for weapons-grade plutonium (WG-Pu) and the decay heat and radiation sources of the materials (products) were also found to be generally higher than for WG-Pu in the transuranics content range of 10% to 100% in the heavy-metal. (authors)

  20. Extraction of Plutonium From Spiked INEEL Soil Samples Using the Ligand-Assisted Supercritical Fluid Extraction (LA-SFE) Technique

    International Nuclear Information System (INIS)

    Fox, R.V.; Mincher, B.J.; Holmes, R.G.G.

    1999-01-01

    In order to investigate the effectiveness of ligand-assisted supercritical fluid extraction for the removal of transuranic contaminations from soils an Idaho National Engineering and Environmental Laboratory (INEEL) silty-clay soil sample was obtained from near the Radioactive Waste Management Complex area and subjected to three different chemical preparations before being spiked with plutonium. The spiked INEEL soil samples were subjected to a sequential aqueous extraction procedure to determine radionuclide portioning in each sample. Results from those extractions demonstrate that plutonium consistently partitioned into the residual fraction across all three INEEL soil preparations whereas americium partitioned 73% into the iron/manganese fraction for soil preparation A, with the balance partitioning into the residual fraction. Plutonium and americium were extracted from the INEEL soil samples using a ligand-assisted supercritical fluid extraction technique. Initial supercritical fluid extraction runs produced plutonium extraction technique. Initial supercritical fluid extraction runs produced plutonium extraction efficiencies ranging from 14% to 19%. After a second round wherein the initial extraction parameters were changed, the plutonium extraction efficiencies increased to 60% and as high as 80% with the americium level in the post-extracted soil samples dropping near to the detection limits. The third round of experiments are currently underway. These results demonstrate that the ligand-assisted supercritical fluid extraction technique can effectively extract plutonium from the spiked INEEL soil preparations

  1. Determination of uranium and plutonium in high active solutions by extractive spectrophotometry

    International Nuclear Information System (INIS)

    Subba Rao, R.V.; Damodaran, K.; Santosh Kumar, G.; Ravi, T.N.

    2000-01-01

    Plutonium and uranium was extracted from nitric acid into trioctyl phosphine oxide in xylene. The TOPO layer was analysed by spectrophotometry. Thoron was used as the chromogenic agent for plutonium. Pyridyl azoresorcinol was used as chromogenic agent for uranium. The molar absorption coefficient for uranium and plutonium was found to be 19000 and 19264 liter/mole-cm, respectively. The correlation coefficient for plutonium and uranium was found to be 0.9994. The relative standard deviation for the determination of plutonium and uranium was found to be 0.96% and 1.4%, respectively. (author)

  2. Solvent extraction process development for high plutonium fuel cycles

    Energy Technology Data Exchange (ETDEWEB)

    Anil Kumar, R; Selvaraj, P G; Natarajan, R; Raman, V R [Reprocessing Group, Indira Gandhi Centre for Atomic Research, Kalpakkam (India)

    1994-06-01

    The purification of high plutonium bearing irradiated fuels using 30% TBP in dodecane diluent requires precise determination of concentration profiles during steady state, transient and process upset conditions. Mathematical models have been developed and a computer code is in use for determining Pu-U concentration profiles in a solvent extraction equipment in a typical reprocessing plant. The process parameters have been optimised for recovery of U and Pu and decontamination from the fission products. This computer code is used to analyse the extraction flow sheets of fuels of two typical Pu-U compositions encountered in Indian fast breeder programme. The analysis include the effect of uncertainty in equilibrium condition prediction by the model and the variation of flows of streams during plant operation. The studies highlight the margin available to avoid second organic phase formation and adjustments required in the process flowsheet. (author). 7 refs., 7 figs., 2 tabs.

  3. Plutonium

    International Nuclear Information System (INIS)

    Koelzer, W.

    1989-03-01

    This report contains with regard to 'plutonium' statements on chemistry, occurrence and reactions in the environment, handling procedures in the nuclear fuel cycle, radiation protection methods, biokinetics, toxicology and medical treatment to make available reliable data for the public discussion on plutonium especially its use in nuclear power plants and its radiological assessment. (orig.) [de

  4. Plutonium

    International Nuclear Information System (INIS)

    Watson, G.M.

    1976-01-01

    Discovery of the neutron made it easy to create elements which do not exist in nature. One of these is plutonium, and its isotope with mass number 239 has nuclear properties which make it both a good fuel for nuclear power reactors and a good explosive for nuclear weapons. Since it was discovered during a war the latter characteristic was put to use, but it is now evident that use of plutonium in a particular kind of nuclear reactor, the fast breeder reactor, will allow the world's resources of uranium to last for millennia as a major source of energy. Plutonium is very radiotoxic, resembling radium in this respect. Therefore the widespread introduction of fast breeder reactors to meet energy demands can be contemplated only after assurances on two points; that adequate control of the radiological hazard resulting from the handling of very large amounts of plutonium can be guaranteed, and that diversion of plutonium to illicit use can be prevented. The problems exist to a lesser degree already, since all types of nuclear reactor produce some plutonium. Some plutonium has already been dispersed in the environment, the bulk of it from atmospheric tests of nuclear weapons. (author)

  5. Plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Miner, William N

    1964-01-01

    This pamphlet discusses plutonium from discovery to its production, separation, properties, fabrication, handling, and uses, including use as a reactor fuel and use in isotope power generators and neutron sources.

  6. Alpha Radiolysis of Nuclear Solvent Extraction Ligands Used for An(III) and Ln(III) Separations

    Energy Technology Data Exchange (ETDEWEB)

    Mezyk, Stephen P. [California State Univ. (CalState), Long Beach, CA (United States); Mincher, Bruce J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Nilsson, Mikael [Univ. of California, Irvine, CA (United States)

    2016-08-01

    This document is the final report for the Nuclear Energy Universities Program (NEUP) grant 10-910 (DE-AC07-05ID14517) “Alpha Radiolysis of Nuclear Solvent Extraction Ligands used for An(III) and Ln(III) Separations”. The goal of this work was to obtain a quantitative understanding of the impacts of both low Linear Energy Transfer (LET, gamma-rays) and high LET (alpha particles) radiation chemistry occurring in future large-scale separations processes. This quantitative understanding of the major radiation effects on diluents and ligands is essential for optimal process implementation, and could result in significant cost savings in the future.

  7. Plutonium

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Plutonium, which was obtained and identified for the first time in 1941 by chemist Glenn Seaborg - through neutron irradiation of uranium 238 - is closely related to the history of nuclear energy. From the very beginning, because of the high radiotoxicity of plutonium, a tremendous amount of research work has been devoted to the study of the biological effects and the consequences on the environment. It can be said that plutonium is presently one of the elements, whose nuclear and physico-chemical characteristics are the best known. The first part of this issue is a survey of the knowledge acquired on the subject, which emphasizes the sanitary effects and transfer into the environment. Then the properties of plutonium related to energy generation are dealt with. Fissionable, like uranium 235, plutonium has proved a high-performance nuclear fuel. Originally used in breeder reactors, it is now being more and more widely recycled in light water reactors, in MOX fuel. Reprocessing, recycling and manufacturing of these new types of fuel, bound of become more and more widespread, are now part of a self-consistent series of operations, whose technical, economical, industrial and strategical aspects are reviewed. (author)

  8. Plutonium

    International Nuclear Information System (INIS)

    Mueller-Christiansen, K.; Wollesen, M.

    1979-01-01

    As emotions and fear of plutonium are neither useful for the non-professionals nor for the political decision makers and the advantages and disadvantages of plutonium can only put against each other under difficulties, the paper wants to present the most essential scientific data of plutonium in a generally understandable way. Each of the individual sections is concluded and they try to give an answer to the most discussed questions. In order to make understanding easier, the scientific facts are only brought at points where it cannot be done without for the correctness of the presentation. Many details were left out knowingly. On the other hand, important details are dealt with several times if it seems necessary for making the presentation correct. The graphical presentations and the figures in many cases contain more than said in the text. They give the interested reader hints to scientific-technical coherences. The total material is to enable the reader to form his own opinion on plutonium problems which are being discussed in public. (orig./HP) [de

  9. Solutions to criticality problems in a plutonium extraction plant

    International Nuclear Information System (INIS)

    Jouannaud, C.; Rodier, J.; Fruchard, Y.; Peyresblanques, H.; Papault, C.; Tabardel-Brian, R.

    1968-08-01

    There are two aspects to nuclear criticality safety: prevention of criticality and protection against the consequences of a possible accident: this report considers these two aspects in the case of the Marcoule Plutonium Extraction Plant. After briefly recalling the various techniques used for avoiding criticality (mass, geometry, concentration, poisoning), the authors describe their application in the plant and show in particular that, a rational use of a favorable geometry is a factor both for security and from an economic point of view. The authors then describe the inside organisation which makes it possible to obtain the necessary intrinsic safety standard right from the advance project stage, and to control the workshop safety during the operation of the plant. The second part of the report deals with the system of protection against the consequences of a possible accident: definition of a typical accident, fixing of the boundaries of a critical zone, safety alarm device, individual and collective dosimetry, evacuation plan and safety instructions. (authors) [fr

  10. Analysis of low-molecular weight radiolysis products in extracts of gamma-irradiated polymers by gas chromatography and high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Buchalla, Rainer; Begley, Timothy H.; Morehouse, Kim M.

    2002-01-01

    Estimating exposure to radiolysis products of polymers is an important part of the regulatory evaluation of packaging materials for use in food irradiation. However, as Koni Grob recently put it, the comprehensive analysis of migrants is a challenge. This paper discusses some of the analytical difficulties and presents results obtained with extracts of irradiated polystyrene and polyamide-6. The results indicate that headspace or thermal desorption techniques may, in some instances, lead to an overestimation of radiolysis product concentrations. It is concluded that validated analytical methods and a better understanding of the underlying radiation chemistry would greatly facilitate the safety assessment of irradiated packaging materials

  11. Removal of plutonium from real time waste using supercritical fluid extraction

    International Nuclear Information System (INIS)

    Sujatha, K.; Sivaraman, N.; Kumar, R.; Srinivasan, T.G.; Vasudeva Rao, P.R.

    2010-01-01

    Supercritical fluid extraction (SFE) technique was carried out for the recovery of plutonium from cellulose waste matrix using supercritical carbon dioxide (SC-CO 2 ) modified with suitable ligands such as octylphenyl N,N-diisobutyl carbamoylmethyl phosphine oxide (φCMPO), tri-n-butyl phosphate (TBP), acetyl acetone, trifluoro acetyl acetone and theonyltrifluoroacetyl acetone (TTA). The maximum plutonium recovery was found to be 99.8% when SC-CO 2 modified with CMPO was employed. About 15mg of plutonium was recovered from waste. (author)

  12. Uranium and plutonium extraction from fluoride melts by lithium-tin alloys

    International Nuclear Information System (INIS)

    Kashcheev, I.N.; Novoselov, G.P.; Zolotarev, A.B.

    1975-01-01

    Extraction of small amounts of uranium (12 wt. % concentration) and plutonium (less than 1.10sup(-10) % concentration) from lithium fluoride melts into the lithium-tin melts is studied. At an increase of temperature from 850 to 1150 deg the rate of process increases 2.5 times. At an increase of melting time the extraction rapidly enhances at the starting moment and than its rate reduces. Plutonium is extracted into the metallic phase for 120 min. (87-96%). It behaves analogously to uranium

  13. Supported extractant membranes for americium and plutonium recovery

    International Nuclear Information System (INIS)

    Muscatello, A.C.; Navratil, J.D.; Killion, M.E.; Price, M.Y.

    1987-01-01

    Solid supported liquid membranes(SLM) are useful in transferring and concentrating americium and plutonium from nitrate solutions. Specifically, DHDECMP(dihexyl-N,N-diethylcarbamoylmethylphosphonate) supported on Accurel or Celgard polypropylene hollow fibers assembled in modular form transfers >95% of the americium and >70% of the plutonium from high nitrate (6.9 M), low acid (0.1 M) feeds into 0.25 M oxalic acid stripping solution. Membranes supporting TBP (tri-n-butylphosphate) also transfer these metal ions. Maximum permeabilities were observed to be 1 x 10 -3 cm sec -1 , similar to the values for other systems. The feed:strip volume ratio shows an inverse relationship to the fraction of metal ion transferred. Cation exchangers may be used to concentrate americium from the strip solution

  14. Uranium decontamination in Purex second plutonium cycle: An example of solvent extraction modeling

    International Nuclear Information System (INIS)

    Hsu, T.C.

    1986-01-01

    The existing Purex flowsheet used in the second plutonium cycle at the Savannah River Plant (SRP) does not remove uranium from the plutonium stream. To develop new flowsheets for the Purex second plutonium cycle, computer simulation using SEPHIS was used. SEPHIS is an ORNL-developed solvent extraction simulation code. Box-Wilson experimental design was used to select the minimum set of process conditions simulated. The calculated results were plotted into three-dimensional response surfaces by SAS/Graph (statistical analysis systems). These surfaces provide a broad and complete overview of the responses. Specific ranges of key variables were then investigated. The second series of process simulations identified flowsheets that provide high uranium decontamination while meeting all other key process requirements. The proposed flowsheet consists of modifying the existing 2B bank flowsheet by relocating the feed, increasing the extractant acidity, and adding a scrub stream. The nuclear safety issue was also examined

  15. A solvent proceed for the extraction of the irradiate uranium and plutonium in the reactor core; Un procede par solvant pour l'extraction du plutonium de l'uranium irradie dans les piles

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, B; Regnaut, P; Prevot, I [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    Description of the conditions of plutonium, fission products and of uranium separation by selective extraction of the nitrates by organic solvent, containing a simultaneous extraction of plutonium and uranium, followed by a plutonium re-extraction after reduction, and an uranium re-extraction. The rates of decontamination being insufficient in this first stage, we also describes the processes of decontamination permitting separately to get the rates wanted for uranium and plutonium. Finally, we describes the beginning of the operation that consists in a nitric dissolution of the active uranium while capturing the products of gaseous fission, as well as the final concentration of the products of fission in a concentrated solution. (authors) [French] Description des conditions de separation du plutonium, des produits de fission et de l'uranium au moyen d'une extraction selective des nitrates par solvant organique, comprenant une extraction simultanee du plutonium et de l'uranium, suivie d'une reextraction du plutonium apres reduction, et d'une reextraction de l'uranium. Les taux de decontamination etant insuffisants dans ce premier stade, on decrit egalement les processus de decontamination permettant separement d'obtenir les taux desires pour l'uranium et le plutonium. Enfin, on decrit aussi le debut de l'operation qui consiste en une dissolution nitrique de l'uranium actif en captant les produits de fission gazeux, ainsi que la concentration finale des produits de fission sous forme de solution concentree. (auteurs)

  16. Fractionation of plutonium in environmental and bio-shielding concrete samples using dynamic sequential extraction

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin

    2010-01-01

    Fractionation of plutonium isotopes (238Pu, 239,240Pu) in environmental samples (i.e. soil and sediment) and bio-shielding concrete from decommissioning of nuclear reactor were carried out by dynamic sequential extraction using an on-line sequential injection (SI) system combined with a specially...

  17. Extraction of plutonium and uranium from oxalate bearing solutions using phosphonic acid

    International Nuclear Information System (INIS)

    Godbole, A.G.; Mapara, P.M.; Swarup, Rajendra

    1995-01-01

    A feasibility study on the solvent extraction of plutonium and uranium from solutions containing oxalic and nitric acids using a phosphonic acid extractant (PC88A) was made to explore the possibility of recovering Pu from these solutions. Batch experiments on the extraction of Pu(IV) and U(VI) under different parameters were carried out using PC88A in dodecane. The results indicated that Pu could be extracted quantitatively by PC88A from these solutions. A good separation of Pu from U could be achieved at higher temperatures. (author). 6 refs., 3 tabs

  18. Evaluation of selectivity and radiolysis behavior of some promising isonicotinamids and dipicolinamides as extractants

    Energy Technology Data Exchange (ETDEWEB)

    Mowafy, E.A. [Atomic Energy Authority, Cairo (Egypt). Hot Labs. Center

    2007-07-01

    A series of long chain isonicotinamides (pyridine-4-carboxamides) and dipicolinamides (pyridine-2,6-dicarboxamides) have been prepared with different substituting groups and the extracting ability for Fe(III), Am(III), Eu(III), Sr(II), Co(II) and Cs(I) from nitric acid solutions has been studied. Distribution ratios of Fe(III) as function of nitric acid concentration, extractants concentration and salting-out agent have been measured by using N,N'-dioctylisonicotinamide (DOINA) and N,N,N',N'-tetraoctyldipicolinamide (TODPA) which were chosen for further studies. Irradiation of DOINA and TOBPA by different gamma doses showed a different extraction behavior for Fe(III). The radiolytic degradation of the investigated amides has been estimated by quantitive IR spectroscopy. The results indicated that the radiolytic stability is influenced by the structure of the investigated amides. Symmetrical isonicotinamides or dipicolinamide seems to be less affected by radiation compared with unsymmetrical isonicotiniamides or dipicolinamides. The extraction of iron from aqueous solutions with the investigated extractants is fast. Separation of iron(III) based on kinetic basis was carried out. (orig.)

  19. Influence of solvent radiolysis on extraction, scrubbing and stripping of uranium and some fission products

    International Nuclear Information System (INIS)

    Gawlowska, W.; Nowak, M.

    1978-01-01

    Radiolytically degraded TBP-n-paraffins solvent was used in the laboratory flow-sheet to study the influence of radiation exposure on decontamination of uranium. The influence of accumulated doses on extraction, scrubbing and stripping of uranium and some fission products has been discussed. (author)

  20. High linear energy transfer degradation studies simulating alpha radiolysis of TRU solvent extraction processes

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, Jeremy [Department of Chemical Engineering and Materials Science - University of California Irvine, 916 Engineering Tower, Irvine, CA, 92697 (United States); Miller, George [Department of Chemistry- University of California Irvine, 2046D PS II, Irvine, CA, 92697 (United States); Nilsson, Mikael [Department of Chemical Engineering and Materials Science - University of California Irvine, 916 Engineering Tower, Irvine, CA, 92697 (United States)

    2013-07-01

    Treatment of used nuclear fuel through solvent extraction separation processes is hindered by radiolytic damage from radioactive isotopes present in used fuel. The nature of the damage caused by the radiation may depend on the radiation type, whether it be low linear energy transfer (LET) such as gamma radiation or high LET such as alpha radiation. Used nuclear fuel contains beta/gamma emitting isotopes but also a significant amount of transuranics which are generally alpha emitters. Studying the respective effects on matter of both of these types of radiation will allow for accurate prediction and modeling of process performance losses with respect to dose. Current studies show that alpha radiation has milder effects than that of gamma. This is important to know because it will mean that solvent extraction solutions exposed to alpha radiation may last longer than expected and need less repair and replacement. These models are important for creating robust, predictable, and economical processes that have strong potential for mainstream adoption on the commercial level. The effects of gamma radiation on solvent extraction ligands have been more extensively studied than the effects of alpha radiation. This is due to the inherent difficulty in producing a sufficient and confluent dose of alpha particles within a sample without leaving the sample contaminated with long lived radioactive isotopes. Helium ion beam and radioactive isotope sources have been studied in the literature. We have developed a method for studying the effects of high LET radiation in situ via {sup 10}B activation and the high LET particles that result from the {sup 10}B(n,a){sup 7}Li reaction which follows. Our model for dose involves solving a partial differential equation representing absorption by 10B of an isentropic field of neutrons penetrating a sample. This method has been applied to organic solutions of TBP and CMPO, two ligands common in TRU solvent extraction treatment processes. Rates

  1. Extraction of plutonium from phosphate containing nitric acid solutions using DHDECMP as extractant (Preprint no. SSC-03)

    International Nuclear Information System (INIS)

    Sagar, V.B.; Pawar, S.M.; Joshi, A.R.; Kasar, U.M.; Sivaramkrishnan, C.K.

    1991-01-01

    Distribution data for the extraction of Pu(IV) by DHDECMP (Di-hexyl, N-N-diethylcarbamoylmethylphosphonate) in xylene from aqueous nitric acid and its mixtures with sulphuric acid and phosphoric acid were obtained to explore the feasibility of recovery of Pu(IV) from analytical waste generated in the laboratory. Based on the data obtained, conditions for recovery of plutonium are suggested. (author). 3 refs., 3 tabs

  2. Idaho Chemical Processing Plant and Plutonium-Uranium Extraction Plant phaseout/deactivation study

    International Nuclear Information System (INIS)

    Patterson, M.W.; Thompson, R.J.

    1994-01-01

    The decision to cease all US Department of Energy (DOE) reprocessing of nuclear fuels was made on April 28, 1992. This study provides insight into and a comparison of the management, technical, compliance, and safety strategies for deactivating the Idaho Chemical Processing Plant (ICPP) at Westinghouse Idaho Nuclear Company (WINCO) and the Westinghouse Hanford Company (WHC) Plutonium-Uranium Extraction (PUREX) Plant. The purpose of this study is to ensure that lessons-learned and future plans are coordinated between the two facilities

  3. Determination of iron in plutonium by extraction of the Fe (2): Bathophenanthroline complex

    International Nuclear Information System (INIS)

    Pichotin, B.; Chasseur, Ph.

    1966-06-01

    The present report describes the method to determine micro quantities of iron in plutonium, by extraction with hexyl alcohol of the complex that give iron (II) with bathophenanthroline (4,7 diphenyl - 1.10 phenanthroline). The reagent has been applied to the determination of amounts of iron ranging from 1 to 10 μg in 20 ml of solvent The determination is made by spectrophotometry at 530 mμ. Others cations present do not interfere. (authors) [fr

  4. Detection of {alpha} particles using semiconductors. Application to the control of plutonium extraction; Detection des particules {alpha} par semiconducteurs application au controle de l'extraction du plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Tanguy, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-03-01

    A study is made of a particles produced by thick sources, using either diffused junction or surface barrier semiconductor detectors for controlling continuously the plutonium extraction process. For this, a presenting apparatus is described in which the solutions to be analyzed flow in contact with the detector protected by a thin mica membrane. A method is described which gives a precise recording of the spectra and which thus allows the separation of two or more {alpha} emitters present in the same solution. This method has been applied to the measurement of {sup 239}Pu in the the presence of {sup 241}Am with an accuracy of {+-}5 per cent. In the second part of the report is considered the detection of plutonium in solutions of {beta} - {gamma} emitting fission products. Pile-up is reduced by using a fast amplification chain associated to totally depleted thin detectors. Under these conditions a few mg of {sup 239}Pu can be detected in solutions of fission products having an activity of 100 curies/liter. A method is given for discriminating {alpha} and {beta} particles, it is based on the difference in the collection times for the charges liberated by these particles in the detector. (author) [French] On etudie la detection de particules {alpha} issues de sources epaisses par detecteurs semiconducteurs a jonction diffusee ou a barriere de surface pour le controle continu du procede d'extraction du plutonium. A cet effet on decrit un appareil presentateur dans lequel les solutions a analyser circulent au contact du detecteur protege par une membrane mince de mica. On decrit une methode qui permet par le trace precis des spectres de separer deux ou plusieurs emetteurs {alpha} presents dans une meme solution. Cette methode a ete appliquee a la mesure du {sup 239}Pu en presence de {sup 241}Am avec une precision de {+-} 5 pour cent. Dans la deuxieme partie on traite de la detection du plutonium dans des solutions de produits de fission emetteurs {beta} and {gamma}. On

  5. Pulse radiolysis

    International Nuclear Information System (INIS)

    Greenshields, H.; Seddon, W.A.

    1982-03-01

    This supplement to two bibliographies published in 1970 and 1972 lists 734 references to the literature of pulse radiolysis, arranged under eight broad subject headings. The references were compiled by searching Biological Abstracts, Chemical Abstracts, Nuclear Science Abstracts and the Weekly List of Papers in Radiation Chemistry issued by the Radiation Chemistry Data Center of Notre Dame University. Full bibliographic data is given for papers published in the period 1971 to 1974. A personal author index listing more than 600 authors and a similar number of co-authors is included

  6. Radical intermediates of low temperature radiolysis of di-tert-butylcyclohexano-18-crown-6/1-octanol extractant

    International Nuclear Information System (INIS)

    Zakurdaeva, O.A.; Nesterov, S.V.; Moscow State Univ.; Feldman, V.I.

    2013-01-01

    Intermediates of low temperature (77 K) X-rays radiolysis of 1-octanol and di-tert-butylcyclohexano-18-crown-6 solutions in 1-octanol were studied by ESR spectroscopy. Hydroxyalkyl CH 3 (CH 2 ) 6 C circle HOH and interior-type alkyl R 1 C circle HR 2 OH radicals were found to be main paramagnetic products stabilized in 1-octanol irradiated at 77 K. In addition to abovementioned radicals, macrocyclic -O-CH 2 -C circle H- and acyclic -C circle H-C(H)=O radicals produced from crown ether were identified in irradiated 1.0 M DtBuCH18C6 solution in octanol. No deviation in radiation-chemical yield of the stabilized acyclic radicals from the value expected in accord with 'additive' rule was observed in the latter case. It was supposed that macrocycle cleavage in DtBuCH18C6 occurred at early stages of radiolysis rather than in secondary radical reactions between products of 1-octanol radiolysis and crown ether. Meanwhile, alkyl radicals formed from 1-octanol can react with crown ether, resulting in formation of macrocyclic products of radiolysis. (orig.)

  7. Radical intermediates of low temperature radiolysis of di-tert-butylcyclohexano-18-crown-6/1-octanol extractant

    Energy Technology Data Exchange (ETDEWEB)

    Zakurdaeva, O.A.; Nesterov, S.V. [Russian Academy of Sciences, Moscow (Russian Federation). Enikolopov Institute of Synthetic Polymer Materials; Moscow State Univ. (Russian Federation). Dept. of Chemistry; Feldman, V.I. [Moscow State Univ. (Russian Federation). Dept. of Chemistry

    2013-03-01

    Intermediates of low temperature (77 K) X-rays radiolysis of 1-octanol and di-tert-butylcyclohexano-18-crown-6 solutions in 1-octanol were studied by ESR spectroscopy. Hydroxyalkyl CH{sub 3}(CH{sub 2}){sub 6}C {sup circle} HOH and interior-type alkyl R{sub 1}C {sup circle} HR{sub 2}OH radicals were found to be main paramagnetic products stabilized in 1-octanol irradiated at 77 K. In addition to abovementioned radicals, macrocyclic -O-CH{sub 2}-C {sup circle} H- and acyclic -C {sup circle} H-C(H)=O radicals produced from crown ether were identified in irradiated 1.0 M DtBuCH18C6 solution in octanol. No deviation in radiation-chemical yield of the stabilized acyclic radicals from the value expected in accord with 'additive' rule was observed in the latter case. It was supposed that macrocycle cleavage in DtBuCH18C6 occurred at early stages of radiolysis rather than in secondary radical reactions between products of 1-octanol radiolysis and crown ether. Meanwhile, alkyl radicals formed from 1-octanol can react with crown ether, resulting in formation of macrocyclic products of radiolysis. (orig.)

  8. Extraction of hexavalent uranium, tetravalent plutonium and fission products by N, N'-tetraalkyldiamides

    International Nuclear Information System (INIS)

    Charbonnel, M.C.

    1988-10-01

    This study deals with the extractive properties of N, N'-tetraalkylglutaramides of generic formula R 2 NC(0)(CH 2 ) 3 C(0)NR 2 . These molecules were considered as alternative extractants to tributylphosphate in nuclear fuels reprocessing. They are selective extractants of uranium and plutonium as far as trivalent actinides and lanthanides remain in aqueous nitric solutions. Distribution ratios measurements and F.T. Infra-Red investigations show that HN0 3 extraction takes place via the formation of the following species: 2L.HN0 3 , L.HN0 3 and L.2HN0 3 in the organic phase (L: glutaramide). Distribution ratios of actinide ions followed by UV-visible spectroscopy and Infra-Red investigations agree with formation of the following neutral organometallic complexes in low nitric acidity conditions: L.U0 2 (N0 3 ) 2 and L.Pu(N0 3 ) 4 and the anionic species at higher acidities: L.U0 2 (N0 3 ) 3 H and L.Pu(N0 3 ) 6 H 2 . Interactions occur through neutral complexes and free molecules of diamides which explain the non ideality of the organic phase. Degradation products of these molecules don't seem to alter the extractive properties of these extractants towards uranium and plutonium [fr

  9. Some studies on the extraction of plutonium from phosphate containing nitric acid solutions using DBDECMP as extractant

    International Nuclear Information System (INIS)

    Sagar, V.B.; Oak, M.S.; Pawar, S.M.; Sivaramakrishnan, C.K.; Patil, S.K.

    1991-01-01

    Extraction studies have been carried out to explore the feasibility of separation of Pu(IV) from phosphate containing analytical wastes generated in the laboratory. Distribution data on the extraction of Pu(IV) from DBDECMP (di-butyl,N,N-diethylcarbamoyl methyl phosphonate) in xylene an aqueous nitric acid and its mixture with sulfuric as well as with sulfuric and phosphoric acids were obtained. Based on the data obtained, the conditions for the recovery of plutonium from such water solutions are suggested. (author) 7 refs.; 1 fig.; 3 tabs

  10. Investigation of behaviour of phosphoric acid and plutonium(4) during extraction by trioctylamine

    International Nuclear Information System (INIS)

    Baranov, Yu.I.; Malysheva, L.P.; Krivokhatskij, A.S.; Savoskina, G.P.; Smirnova, E.A.

    1980-01-01

    Chemical studies of the H 3 PO 4 -TOA-diluent system are carried out in order to investigate the behaviour of plutonium(4) in this system. Isotherms of H 3 PO 4 extraction for different TOA concentrations in benzene are presented. The effect of diluents on the extraction of H 3 PO 4 by trioctylamine is studied. IR and PMR spectra of H 3 PO 4 -TOA-CCl 4 solutions are studied. H 3 PO 4 is believed to form with TOA the following compounds: (TOAH) 3 PO 4 , (TOAH) 2 HPO 4 and [(TOAH) 2 HPO 4 ] 3 xH 3 PO 4

  11. Factors Controlling Redox Speciation of Plutonium and Neptunium in Extraction Separation Processes

    Energy Technology Data Exchange (ETDEWEB)

    Paulenova, Alena [Principal Investigator; Vandegrift, III, George F. [Collaborator

    2013-09-24

    The objective of the project was to examine the factors controlling redox speciation of plutonium and neptunium in UREX+ extraction in terms of redox potentials, redox mechanism, kinetics and thermodynamics. Researchers employed redox-speciation extractions schemes in parallel to the spectroscopic experiments. The resulting distribution of redox species w studied uring spectroscopic, electrochemical, and spectro-electrochemical methods. This work reulted in collection of data on redox stability and distribution of redox couples in the nitric acid/nitrate electrolyte and the development of redox buffers to stabilize the desired oxidation state of separated radionuclides. The effects of temperature and concentrations on the redox behavior of neptunium were evaluated.

  12. Extraction of plutonium(IV) by bis(2-ethylhexyl) sulfoxide: a novel branched-chain extractant (Preprint No. ST.23)

    International Nuclear Information System (INIS)

    Shukla, J.P.; Kedari, C.S.

    1989-01-01

    Di-n-alkyl sulfoxides offer certain distint advantages over other common extractants for use in actinides separation particularly in the presence of high radiation fields. Despite widespread interest in these extractants, practical applications of such sulfoxides in nuclear fuel reprocessing have been seriously hampered owing to their poor solubility in common aliphatic hydrocarbon diluents. Recently a promising new branched-chain sulfoxide extractant, bis( 2-ethylhexyl) sulfoxide (BESO) has been introduced as a novel extracting agent for uranium. It possesses almost all the advantages of other sulfoxides, but excels the rest in terms of its complete miscibility with dodecane and the highest Ksub(H) value reported for any sulfoxide. As a part of comprehensive program to explore its analytical usefulness, data concerning preliminary studies on the extraction of plutonium with BESO form nitric acid solutions are reported. (author)

  13. Study of a plutonium substitute for the reducing back-extraction in low flow rate contactors

    International Nuclear Information System (INIS)

    Morell, M.

    1998-01-01

    The aim of this work is to define and carry out a non-radioactive redox chemical system, similar to those of the plutonium, in a reducing back-extraction operation. In the first part, we have replaced our study within the context of the spent fuels. The choice of cerium as a plutonium substitute is justified and the used centrifugal drier described. The current process is presented and the set problem explained. The experimental study concerns essentially the research of reducers of the chosen substitute, the stability of ceric solutions, the measurement of distribution coefficients and the study of redox chemical kinetics. In the last part, are given the used simulation tools (development of a mathematical model in a first step and adaptation of the PAREX code in the second step) and the results of their comparison with the experimental data

  14. Liquid-liquid extraction of plutonium and americium by cekanoic acid from alkaline medium

    International Nuclear Information System (INIS)

    Venugopal Chetty, K.; Sagar, V.; Swarup, R.

    2001-01-01

    Liquid-liquid extraction studies of plutonium and americium from aqueous carbonate medium using a high molecular weight carboxylic acid namely cekanoic acid in different diluents has been carried out. The distribution ratio (D) values for Pu(IV) and Am(III) under various parameters such as concentration of extractant, Na 2 CO 3 and initial pH were obtained. Results indicated that Pu(IV) and Am(III) could be satisfactorily extracted together or individually from aqueous carbonate medium using cekanoic acid in different diluents like carbon tetrachloride, cyclohexane, toluene, n-dodecane or solvesso-100. The D values for Pu(IV) and Am(III) also indicated the possibility of their mutual separation. The back extraction of Pu and Am with different reagents was also studied. (orig.)

  15. Solid-phase extraction of plutonium in various oxidation states from simulated groundwater using N-benzoylphenylhydroxylamine

    International Nuclear Information System (INIS)

    Perevalov, S.A.; Malofeeva, G.I.; Kuzovkina, E.V.; Spivakov, B.Ya.

    2013-01-01

    Solid-phase extraction of plutonium in different individual and mixed oxidation states from simulated groundwater (pH 8.5) was studied. The extraction of plutonium species was carried out in a dynamic mode using DIAPAK C16 cartridges modified by N-benzoylphenylhydroxylamine (BPHA). It was shown that the extent of recovery depends on the oxidation state of plutonium. The extraction of Pu(IV) was at the level of 98-99% regardless of the volume and flow-rate of the sample solution. Pu(V) was extracted by 90-95% and 75-80% from 10- and 100-mL aliquots of the samples, respectively, whereas the extraction of Pu(VI) did not exceed 45-50%. An equimolar mixture of Pu(IV), Pu(V), and Pu(VI) was extracted by 74%. The distribution coefficients (K d ) and kinetic exchange capacities (S) of plutonium in various oxidation states were measured. It was found that during the sorption process, Pu(V) was reduced to Pu(IV) by 80-90% after an hour-long contact with the solid phase. Pu(VI) is reduced to Pu(V) by 34% and to Pu(IV) by 55%. In the case of mixed-valent solution of plutonium, only Pu(V) and Pu(IV) were found in the effluents. (author)

  16. Plutonium and americium recovery from spent molten-salt-extraction salts with aluminum-magnesium alloys

    International Nuclear Information System (INIS)

    Cusick, M.J.; Sherwood, W.G.; Fitzpatrick, R.F.

    1984-01-01

    Development work was performed to determine the feasibility of removing plutonium and americium from spent molten-salt-extraction (MSE) salts using Al-Mg alloys. If the product buttons from this process are compatible with subsequent aqueous processing, the complex chloride-to-nitrate aqueous conversion step which is presently required for these salts may be eliminated. The optimum alloy composition used to treat spent 8 wt % MSE salts in the past yielded poor phase-disengagement characteristics when applied to 30 mol % salts. After a limited investigation of other alloy compositions in the Al-Mg-Pu-Am system, it was determined that the Al-Pu-Am system could yield a compatible alloy. In this system, experiments were performed to investigate the effects of plutonium loading in the alloy, excess magnesium, age of the spent salt on actinide recovery, phase disengagement, and button homogeneity. Experimental results indicate that 95 percent plutonium recoveries can be attained for fresh salts. Further development is required for backlog salts generated prior to 1981. A homogeneous product alloy, as required for aqueous processing, could not be produced

  17. Characterization of past and present solid waste streams from the Plutonium-Uranium Extraction Plant

    International Nuclear Information System (INIS)

    Pottmeyer, J.A.; Weyns, M.I.; Lorenzo, D.S.; Vejvoda, E.J.; Duncan, D.R.

    1993-04-01

    During the next two decades the transuranic wastes, now stored in the burial trenches and storage facilities at the Hanford Site, are to be retrieved, processed at the Waste Receiving and Processing Facility, and shipped to the Waste Isolation Pilot Plant near Carlsbad, New Mexico for final disposal. Over 7% of the transuranic waste to be retrieved for shipment to the Waste Isolation Pilot Plant has been generated at the Plutonium-Uranium Extraction (PUREX) Plant. The purpose of this report is to characterize the radioactive solid wastes generated by PUREX using process knowledge, existing records, and oral history interviews. The PUREX Plant is currently operated by the Westinghouse Hanford Company for the US Department of Energy and is now in standby status while being prepared for permanent shutdown. The PUREX Plant is a collection of facilities that has been used primarily to separate plutonium for nuclear weapons from spent fuel that had been irradiated in the Hanford Site's defense reactors. Originally designed to reprocess aluminum-clad uranium fuel, the plant was modified to reprocess zirconium alloy clad fuel elements from the Hanford Site's N Reactor. PUREX has provided plutonium for research reactor development, safety programs, and defense. In addition, the PUREX was used to recover slightly enriched uranium for recycling into fuel for use in reactors that generate electricity and plutonium. Section 2.0 provides further details of the PUREX's physical plant and its operations. The PUREX Plant functions that generate solid waste are as follows: processing operations, laboratory analyses and supporting activities. The types and estimated quantities of waste resulting from these activities are discussed in detail

  18. Simultaneous determinations of uranium, thorium, and plutonium in soft tissues by solvent extraction and alpha-spectrometry

    International Nuclear Information System (INIS)

    Singh, N.P.; Zimmerman, C.J.; Lewis, L.L.; Wrenn, M.E.

    1984-01-01

    A radiochemical procedure for the simultaneous determination of uranium, thorium, and plutonium, in soft tissues has been developed. The weighed amounts of tissues, spiked with 232 U, 242 Pu, and 229 th tracers, are wet ashed. Uranium, thorium, and plutonium are coprecipitated with iron as hydroxides, dissolved in concentrated HCl and the acidity adjusted to 10 M. Uranium and plutonium are extracted into 20% TLA solution in xylene, leaving thorium in the aqueous phase. Plutonium is back-extracted by reducing to the trivalent state with 0.05 M NH 4 I solution in 8 M HCl, and uranium is back-extracted with 0.1 M HCl. Thorium is extracted into 20% TLA solution from 4 M HNO 3 and back-extracted with 10 M HCl. Uranium, thorium and plutonium are electrodeposited separately onto platinum discs and counted alpha-spectrometrically using surface barrier silicon diodes and a multichannel analyzer. The method was developed using bovine liver and applied to dog and human tissues. The mean radiochemical recoveries of these actinides in different organs were better than 70%. 6 references, 2 tables

  19. Uranium, neptunium and plutonium kinetics of extraction by tributylphosphate and trilaurylamine in a centrifugal contactor

    International Nuclear Information System (INIS)

    Bergeonneau, P.; Jaouen, C.; Germain, M.; Bathellier, A.

    1977-01-01

    Uranium, plutonium and neptunium kinetics of transfer between various aqueous nitric solutions and solvents have been measured at the laboratory scale, using a centrifugal contactor especially developed in the laboratory. The transfer kinetics of nitric acid, hexavalent U, tetravalent U, Np and Pu from nitric acid solutions into 30% TBP in r-dodecane and 10% trilaurylamine in r-dodecane have been studied. The effects of rotation speed, temperature, initial nitric acid concentration, metal concentration on extraction and stripping kinetics have been investigated. The results obtained show that TBP extraction and stripping are more rapid than trilaurylamine ones. The low activation energies of transfer reactions with TBP suggest that both in extraction and stripping, the transfer rate is limited by the diffusion of the species in the aqueous and organic phases. For trilaurylamine, the transfer mechanism appears more complex

  20. Solutions to criticality problems in a plutonium extraction plant; Solutions apportees aux problemes de criticite d'une usine d'extraction du plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Jouannaud, C.; Rodier, J.; Fruchard, Y.; Peyresblanques, H.; Papault, C.; Tabardel-Brian, R. [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule, service d' extraction du plutonium, service de protection contre les radiations et d' assainissement radioactif

    1968-08-01

    There are two aspects to nuclear criticality safety: prevention of criticality and protection against the consequences of a possible accident: this report considers these two aspects in the case of the Marcoule Plutonium Extraction Plant. After briefly recalling the various techniques used for avoiding criticality (mass, geometry, concentration, poisoning), the authors describe their application in the plant and show in particular that, a rational use of a favorable geometry is a factor both for security and from an economic point of view. The authors then describe the inside organisation which makes it possible to obtain the necessary intrinsic safety standard right from the advance project stage, and to control the workshop safety during the operation of the plant. The second part of the report deals with the system of protection against the consequences of a possible accident: definition of a typical accident, fixing of the boundaries of a critical zone, safety alarm device, individual and collective dosimetry, evacuation plan and safety instructions. (authors) [French] La securite vis-a-vis des risques de criticite revet deux aspects: la prevention de la criticite et la protection contre les consequences d'un accident eventuel: le present rapport developpe ces deux aspects dans le cas de l'Usine d'Extraction du Plutonium de Marcoule. Apres avoir rappele les differentes techniques de prevention de la criticite (masse, geometrie, concentration, empoisonnement), les auteurs decrivent leur application a l'Usine et montrent notamment que l'utilisation rationnelle de la geometrie favorable est un double facteur de securite et d'economie. Les auteurs decrivent ensuite l'organisation interieure qui permet de realiser la securite intrinseque des le stade d'un avant projet et de controler la securite des ateliers au cours de la vie de l'Usine. La deuxieme partie du rapport est consacree au systeme de protection contre les

  1. Solutions to criticality problems in a plutonium extraction plant; Solutions apportees aux problemes de criticite d'une usine d'extraction du plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Jouannaud, C; Rodier, J; Fruchard, Y; Peyresblanques, H; Papault, C; Tabardel-Brian, R [Commissariat a l' Energie Atomique, Chusclan (France). Centre de Production de Plutonium de Marcoule, service d' extraction du plutonium, service de protection contre les radiations et d' assainissement radioactif

    1968-08-01

    There are two aspects to nuclear criticality safety: prevention of criticality and protection against the consequences of a possible accident: this report considers these two aspects in the case of the Marcoule Plutonium Extraction Plant. After briefly recalling the various techniques used for avoiding criticality (mass, geometry, concentration, poisoning), the authors describe their application in the plant and show in particular that, a rational use of a favorable geometry is a factor both for security and from an economic point of view. The authors then describe the inside organisation which makes it possible to obtain the necessary intrinsic safety standard right from the advance project stage, and to control the workshop safety during the operation of the plant. The second part of the report deals with the system of protection against the consequences of a possible accident: definition of a typical accident, fixing of the boundaries of a critical zone, safety alarm device, individual and collective dosimetry, evacuation plan and safety instructions. (authors) [French] La securite vis-a-vis des risques de criticite revet deux aspects: la prevention de la criticite et la protection contre les consequences d'un accident eventuel: le present rapport developpe ces deux aspects dans le cas de l'Usine d'Extraction du Plutonium de Marcoule. Apres avoir rappele les differentes techniques de prevention de la criticite (masse, geometrie, concentration, empoisonnement), les auteurs decrivent leur application a l'Usine et montrent notamment que l'utilisation rationnelle de la geometrie favorable est un double facteur de securite et d'economie. Les auteurs decrivent ensuite l'organisation interieure qui permet de realiser la securite intrinseque des le stade d'un avant projet et de controler la securite des ateliers au cours de la vie de l'Usine. La deuxieme partie du rapport est consacree au systeme de protection contre les consequences d'un accident eventuel: definition d

  2. Recovery of plutonium and americium from chloride salt wastes by solvent extraction

    International Nuclear Information System (INIS)

    Reichley-Yinger, L.; Vandegrift, G.F.

    1987-01-01

    Plutonium and americium can be recovered from aqueous waste solutions containing a mixture of HCl and chloride salt wastes by the coupling of two solvent extraction systems: tributyl phosphate (TBP) in tetrachloroethylene (TCE) and octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) in TCE. In the flowsheet developed, the salt wastes are dissolved in HCl, the Pu(III) is oxidized to the IV state with NaClO 2 and recovered in the TBP-TCE cycle, and the Am is then removed from the resultant raffinate by the CMPO-TCE cycle. The consequences of the feed solution composition and extraction behavior of these species on the process flowsheet design, the Pu-product purity, and the decontamination of the aqueous raffinate from transuranic elements are discussed. 16 refs., 6 figs

  3. Role of ligand basicity and stereochemistry in the extraction of plutonium(IV) isoxazolonates

    International Nuclear Information System (INIS)

    Mohapatra, P.K.; Manchanda, V.K.

    2003-01-01

    The extraction behaviour of plutonium (IV) was investigated from nitric acid and perchloric acid using 3-phenyl-4-benzoyl-5-isoxazolone (HPBI) as well as a mixture of HPBI and tri-n-octyl phosphine oxide (TOPO) in xylene. Studies on the binary extraction system Pu(IV)-HPBI indicated extraction of species of the type Pu(PBI) 4 . In the presence of TOPO, while species of the type Pu(PBI) 3 (ClO 4 ).(TOPO) and Pu(PBI) 4 .TOPO were co-extracted from perchloric acid medium, a mixture of Pu(PBI) 2 (NO 3 ) 2 .2TOPO, Pu(PBI) 3 (NO 3 ).(TOPO) and Pu(PBI) 4 .TOPO were co-extracted from nitric acid medium. In addition to the electronic factors, steric factors were found to play a significant role during the formation of binary/ternary/quaternary complexes. The steric hindrance due to the unusual conformation of the isoxazolone led to lowering of the equilibrium constants for both the binary and ternary extraction systems. Possible steric factor influences are explained with the help of molecular modelling. (orig.)

  4. Liquid-liquid extraction of plutonium(IV) in monoamide - ammonium ionic liquid mixture

    International Nuclear Information System (INIS)

    Rout, Alok; Venkatesan, K.A.; Antony, M.P.

    2016-01-01

    Room temperature ionic liquid (RTIL) can be regarded as a sustainable alternative to the conventional molecular diluent, n-dodecane (n-DD), in solvent extraction process. Replacement of volatile organic solvents by RTILs in solvent extraction could lead to inherently safer processes. As far as the cation is concerned, most of the studies reported in literature are focused on imidazolium-based ionic liquids. In contrast to imiadazolium ionic liquids, quarternary ammonium ionic liquids like trioctylmethylammonium chloride (Aliquat 336), trioctylmethylammonium nitrate etc., do not exhibit any cation exchange with the metal ions from aqueous phase during extraction. However, there is no report available in literature that emphasizes the application of trioctylmethylammonium bis(trifluoromethane-sulfonyl)imide ((N_1_8_8_8)(NTf_2)) ionic liquid, for the extraction of Pu(IV). In this paper, we report the advantages of using the ionic liquid, trioctylmethylammonium bis(trifluoromethanesulfonyl)imide ((N_1_8_8_8)(NTf_2)), as diluent, for the extraction of plutonium(IV) in DHOA/(N_1_8_8_8)(NTf_2)

  5. Contribution to the study of the process of purification of plutonium by extraction with trilaurylamine

    International Nuclear Information System (INIS)

    Saey, Jean-Claude

    1966-01-01

    This work addresses the process of plutonium purification which uses trilaurylamine nitrate. In order to use this nitrate in its solid state and at ordinary temperature, a secondary solvent must be added which must have some properties: low volume mass and viscosity, high boiling and ignition temperatures, rather low miscibility with water, high stability in front of joint actions of nitric acid and radiations, and no reaction with the alkylammonium nitrate and the complex. Thus, the author addresses phenomena of immiscibility and identifies some important molecular characteristics which could lead to the selection of another secondary solvent than dodecane. The decalin seem interesting and its behaviour is studied. A mixing of dodecane and decalin is used as extraction mixing. The obtained results are discussed. Finally, the author notices that using this mixing in the plutonium purification process results in a large increase of metal concentrations and a decrease of risks of crystallisation, without any major drawback, in a continuously operating micro-industrial installation

  6. Extraction of plutonium from lean residues by room-temperature fluoride volatility

    International Nuclear Information System (INIS)

    Campbell, G.M.; Foropoulos, J.; Kennedy, R.C.; Dye, B.A.; Behrens, R.G.

    1990-01-01

    The use of dioxygen difluoride and krypton difluoride for the recovery of plutonium from lean residues by conversion to gaseous plutonium hexa-fluoride is being investigated. The synthesis of dioxygen difluoride in practical quantity has been demonstrated. Fluorination of plutonium compounds under ideal conditions supports the contention that a viable process can be developed. Application of the method to lean plutonium residues is in the early stage of development

  7. Evaluation of several novel diamide based ligands for selective extraction of tetravalent plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Sivaramakrishna, Mallampalli; Nayak, Shashikant K. [Heavy Water Board, V.S. Bhavan, Mumbai (India); Raut, Dhaval R.; Mohapatra, Prasanta K. [Bhabha Atomic Research Center, Mumbai (India). Radiochemistry Division; Nayak, Sandip K. [Bhabha Atomic Research Center, Mumbai (India). Bioorganic Division

    2017-06-01

    The present paper describes the selective extraction of tetravalent plutonium employing several diamide ligands containing aromatic spacer groups. The ligands containing two amide functional groups attached to a 2,4,6-tri-phenyl pyridine moiety with different substituents viz.; L{sub I} (iso-butyl), L{sub II}(n-butyl), L{sub III}(n-octyl), L{sub IV} (2-ethylhexyl) at the amidic nitrogen atom were evaluated for the extraction of Pu(IV) using their nitrobenzene solutions. The distribution ratio values of Pu(IV) with the diamide ligands followed the order: L{sub II}>L{sub I}>L{sub III}>L{sub IV} and were significantly higher than those of metal ions such as Cs(I), Sr(II), Am(III) and Eu(III). The distribution ratio values of U(VI) were about 2-3 orders magnitude lower than those of Pu(IV). The extraction and stripping kinetics were found to be moderately fast and it took less than 30 min (less than 5 min for L{sub I} and L{sub IV}) to obtain equilibrium D values. The extraction was found to be increasing with the aqueous phase nitric acid concentration conforming to a solvation mechanism of extraction. The extracted species contained two ligand molecules for L{sub I} and L{sub II} while monosolvates were observed for the other two extractants. The ligands showed good radiation stability up to an absorbed dose of 630 kGy.

  8. Thermodynamics of synergistic extraction of hexavalent plutonium with HPMBP and neutral donors: monodentate versus bidentate

    International Nuclear Information System (INIS)

    Lohithakshan, K.V.; Mithapara, P.D.; Pai, S.A.; Aggarwal, S.K.; Jain, H.C.

    1996-01-01

    Synergistic extraction of hexavalent plutonium was studied from HNO 3 medium (0.05 M) with 1-phnyl, 3-methyl, 4-benzoyl, pyrazolone-5 (HPMBP) and different monodentate neutral donors viz. diphenyl sulphoxide (DPSO), tri-n-butyl phosphate (TBP) and tri-n-octyl phosphine oxide (TOPO) using benzene as a diluent. Thermodynamic parameters (ΔG, ΔH, ΔS) evaluated by performing the experiments at various fixed temperatures (288 K to 318 K) were compared with those reported previously for the bidentate neutral donors (DBDECMP, DHDECMP and CMPO). The net enthalpy changes were negative and comparable. The monodentate neutral donors, however, showed a larger decrease in the entropy values. Further, the negative values of enthalpy and entropy changes indicated that the organic adduct formation is an addition reaction as reported ealier for the bidentate donors. (orig.)

  9. Radiolysis of spray solutions

    International Nuclear Information System (INIS)

    Habersbergerova, A.; Janovsky, I.

    1985-01-01

    The factors were studied affecting thiosulfate radiolysis in the so-called spray solution for nuclear power plant containments. The reaction mechanism of primary radiolytic reactions leading to thiosulfate decomposition was studied using pulse radiolysis. Also measured was hydrazine loss in the irradiation of the bubbling solution intended for the capture of volatile chemical forms of radioiodine. Pulse radiolysis was used to study the kinetics of hydrazine reaction with elemental iodine. (author)

  10. Extraction of plutonium(IV) by diglycolamide extractants in room temperature ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Prabhu, Dattaprasad R.; Raut, Dhaval R.; Murali, Mallekav S.; Mohapatra, Prasanta K. [Bhabha Atomic Research Centre, Mumbai (India). Radiochemistry Div.

    2017-06-01

    Extraction of Pu(IV) was investigated using solutions of two diglycolamide extractants viz., N,N,N{sup '},N{sup '}-tetra-n-octyldiglycolamide (TODGA) and its branched homolog, N,N,N{sup '},N{sup '}-tetra(2-ethylhexyl) diglycolamide (T2EHDGA), dissolved in two imidazolium based room temperature ionic liquids viz., 1-butyl-3-methylimidazolium bis(trifluoromethanesulphonyl) imide ([C{sub 4}mim][NTf{sub 2}]) and 1-octyl-3-methylimidazolium bis(trifluoromethanesulphonyl) imide ([C{sub 8}mim][NTf{sub 2}]) from aqueous nitric acid medium. The extraction kinetics was found to be extremely slow which is reported for the first time for analogous extraction systems and took as long as 30 h to attain equilibrium D{sub Pu} values. In general, TODGA based solvents showed better extraction of Pu(IV) than the T2EHDGA based solvents, one order of magnitude higher, and though both the ionic liquids ultimately yielded comparable D{sub Pu} values, attainment of equilibrium was slower with [C{sub 4}mim][NTf{sub 2}]. The extracted species conformed to 1:1 for TODGA in both the ionic liquids while a mixture of 1:1 and 1:2 species was observed for T2EHDGA at 1 M HNO{sub 3} which changed to 1:1 species at 4 M HNO{sub 3}. The extracted species is proposed to be (Pu(L){sub x}{sup 4+}){sub IL} (where, L is the extractant and x=1 or 2) at lower acidities suggesting a cation exchange mechanism which changes over to (Pu(NO{sub 3}){sub 4} .L){sub IL} at 4 M HNO{sub 3} conforming to a solvation mechanism for all the systems except for T2EHDGA-[C{sub 8}mim][NTf{sub 2}]. UV-VIS spectroscopic studies were carried out to throw light on the nature of the extracted species.

  11. Some studies on the extraction of plutonium from phosphate containing nitric acid solutions using DBDECMP as extractant (Preprint No. CT-24)

    International Nuclear Information System (INIS)

    Sagar, V.B.; Pawar, S.M.; Oak, M.S.; Sivaramakrishnan, C.K.

    1988-02-01

    Extraction studies have been carried out to explore the feasibility of separation of Pu(IV) from phosphate containing analytical wastes generated in the laboratory. Distribution data on the extraction of Pu(IV) from dibutyl-N,N diethylcarbamoylmethylenephosphonate (DBDECMP) in xylene from an aqu eous nitric acid and its mixture with sulphuric as well as with sulphuric and phosphoric acids were obtained. Based on the data obtained the conditions for the recovery of plutonium from such waste solutions are suggested. (author)

  12. Application of extraction chromatography to the recovery of neptunium, plutonium and americium from an industrial waste

    International Nuclear Information System (INIS)

    Madic, C.; Kertesz, C.; Sontag, R.; Koehly, G.

    1980-01-01

    A pilot scale investigation was made to evaluate the possible application of the extraction chromatographic method (LLC) to the partitioning of alpha emitters from liquid wastes containing traces of transuranium elements. A secondary purpose was to obtain pure Am0 2 , which is used to produce alpha, gamma, and neutron sources. The process developed for alpha partitioning consists essentially of the extraction of macro amounts of uranium with 30% TBP in dodecane in mixer-settlers, then coextraction of Np-237, Pu-239, and Am-241 by LLC on a macro column filled with di-n-hexyl-octoxy-methyl-phosphine oxide (POX.11) adsorbed on an inert support. In each run about 200 liters of initial waste are decontaminated of alpha emitters. The loading step is followed by selective elution of americium, neptunium, and plutonium. The americium eluate is then subjected to the following operations: (1) separation of Am from Fe and Cd by LLC on a TBP column and (2) separation of Am from lanthanide traces by LLC on an HD(DiBM)P column after oxidation of Am(III) to Am(VI). The Am in the eluate is subsequently reduced to Am(III) and precipitated as oxalate with oxalic acid. The oxalate is then filtered and calcined to yield pure AmO 2

  13. Transplutonium elements production program: extraction chromatographic process for plutonium irradiated targets

    International Nuclear Information System (INIS)

    Bourges, J.; Madic, C.; Koehly, G.

    1980-01-01

    The treatment of irradiated plutonium targets by extraction chromatography allowed the purification of the isotopes 243 Am and 244 Cm on the scale of few tens of grams. This process proved to be extremely simple and flexible, and yielded results which are reproducible in time. The chief advantage of the TBP process over the HDEHP process in high and medium activity conditions lies in the rapid absorption/desorption kinetics of the elements to be purified and in the separation of americium from curium, which largely offsets its lower selectivity for lanthanide elements. it is certainly possible to improve the performance of this process by: a) optimization of the characteristics of the stationary phase, b) improvement in the filling technique and in hydraulic operation of the columns, c) on-line analysis of americium (the key element in actinide/lanthanide separation) in the eluate. The application of extraction chromatography with HD(DiBM)P to the purification of 243 Am of the end of treatment makes the process more consistent, eliminates the delicate stages implemented in hot cell, and considerably improves final product quality

  14. Gas phase pulse radiolysis

    International Nuclear Information System (INIS)

    Jonah, C.D.; Andong Liu; Mulac, W.A.

    1987-01-01

    Gas phase pulse radiolysis, a technique which can be used to study many different phenomena in chemistry and physics, is discussed. As a source of small radicals, pulse radiolysis is important to the field of chemistry, particularly to combustion and atmospheric kinetics. The reactions of 1,3-butadiene, allene, ethylene and acetylene with OH are presented. 52 refs., 1 fig., 1 tab

  15. Plutonium association with selected solid phases in soils of Rocky Flats, Colorado, using sequential extraction technique

    International Nuclear Information System (INIS)

    Litaor, M.I.; Ibrahim, S.A.

    1996-01-01

    Plutonium contamination in the soil environs of Rock Flats, CO, has been a potential health risk to the public since the late 1960s. Although the measurement of total activity of Pu-239 + 240 in the soil is important information in appraising this risk, total activity does not provide the information required to characterize the geochemical behavior that affects the transport of Pu from the soil and vadose zone to groundwater. A sequential extraction experiment was conducted to assess the geochemical association of Pu with selected mineralogical and chemical phases of the soil. In the surface horizons, Pu-239 + 240 was primarily associated with the organic C (45-65%), sesquioxides (20-40%), and the residual fraction (10-15%). A small portion of Pu-239+240 was associated with soluble (0.09-0.22%), exchangeable (0.04-0.08%), and carbonates (0.57-7.0%) phases. These results suggest that under the observed pH and oxic conditions, relatively little Pu-239 + 240 is available for geochemically induced transport processes. Uncommon hydrogeochemical conditions were observed during the spring of 1995, which may have facilitated a partial dissolution of sesquioxides followed by desorption of Pu resulting in increased Pu mobility. Systematic errors in the sequential extraction experiment due to postextraction readsorption were evaluated using Np-237 tracer as a surrogate to Pu-239. The results suggested that postextraction readsorption rates were insignificant during the first 30 min after extraction for most chemical and mineralogical phases under study. 50 refs., 2 figs., 5 tabs

  16. Synergistic extraction of hexavalent plutonium by HTTA and HPMBP using mono- and bi- functional neutral donors: a comparative study

    International Nuclear Information System (INIS)

    Lohithakshan, K.V.; Mithapara, P.D.; Pai, S.A.; Aggarwal, S.K.

    1997-01-01

    Thermodynamics and synergistic extraction of hexavalent plutonium were studied from HNO 3 medium (0.05M) with HTTA and HPMBP and various neutral donors viz. DPSO, TBP, TOPO (monofunctional) and DBDECMP, DHDECMP, CMPO (bifunctional) using benzene as a diluent. The net enthalpy and entropy changes were interpreted in terms of different organic phase adduct formation reaction mechanisms i.e. substitution in HTTA vs addition in HPMBP. (author). 4 refs., 2 figs

  17. Functional design criteria for the 242-A evaporator and PUREX [Plutonium-Uranium Extraction] Plant condensate interim retention basin

    International Nuclear Information System (INIS)

    Cejka, C.C.

    1990-01-01

    This document contains the functional design criteria for a 26- million-gallon retention basin and 10 million gallons of temporary storage tanks. The basin and tanks will be used to store 242-A Evaporator process condensate, the Plutonium-Uranium Extraction (PUREX) Plant process distillate discharge stream, and the PUREX Plant ammonia scrubber distillate stream. Completion of the project will allow both the 242-A Evaporator and the PUREX Plant to restart. 4 refs

  18. Surveillance and Maintenance Plan for the Plutonium Uranium Extraction (PUREX) Facility

    International Nuclear Information System (INIS)

    Woods, P.J.

    1998-05-01

    This document provides a plan for implementing surveillance and maintenance (S ampersand M) activities to ensure the Plutonium Uranium Extraction (PUREX) Facility is maintained in a safe, environmentally secure, and cost-effective manner until subsequent closure during the final disposition phase of decommissioning. This plan has been prepared in accordance with the guidelines provided in the U.S. Department of Energy (DOE), Office of Environmental Management (EM) Decommissioning Resource Manual (DOE/EM-0246) (DOE 1995), and Section 8.6 of TPA change form P-08-97-01 to the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) (Ecology, et al. 1996). Specific objectives of the S ampersand M program are: Ensure adequate containment of remaining radioactive and hazardous material. Provide security control for access into the facility and physical safety to surveillance personnel. Maintain the facility in a manner that will minimize potential hazards to the public, the environment, and surveillance personnel. Provide a plan for the identification and compliance with applicable environmental, safety, health, safeguards, and security requirements

  19. Contribution to the study of liquid-liquid extraction dynamics in the case of fast transfers. Extractions of uranium, plutonium and neptunium in a laboratory centrifugal extractor

    International Nuclear Information System (INIS)

    Bergeonneau, Philippe

    1978-01-01

    The liquid-liquid extraction (also named solvent-based extraction) is a very important technique for the reprocessing of irradiated nuclear fuels. This research thesis is based on the use of a laboratory centrifugal extractor which allows interesting conditions to be achieved: fast transfer due to an intense solution mixing, very short duration of contact between solutions. Thus, after a report of a bibliographical study on chemical mechanisms of extraction, on the composition of extracted species, on extraction kinetics, and on centrifugal extractors, this thesis reports the design, fabrication and use of a centrifugal extractor: presentation of fundamental principles, description and characteristics (materials, hydrodynamic operation test and problems, prototype). It reports studies of fast transfer kinetics: mathematical processing, result interpretation, results and discussions of extraction kinetics for nitric acid, uranium VI and IV, plutonium IV, neptunium IV, and comparison of the different extraction kinetics

  20. Design and synthesis of a new class of diamides for selective extraction of plutonium

    International Nuclear Information System (INIS)

    Mallampalli, Sivaramakrishna; Kumar, Amar; Nayak, S.K.; Nayak, Sandip K.; Raout, D.; Mohapatra, P.K.

    2016-01-01

    The immense interest in purification of plutonium (Pu) originated from its dual use both in domestic power production as well as in strategic applications. As on today, the most prevalent application for 238 Pu is its use as an important fuel for heat and power sources for space exploration. Recently, a useful Pu selective diamide solvent (BenzoDODA) in n-dodecane diluent has been reported with a relatively high distribution coefficient (6.74 at 3M HNO 3 and 9.5 at 6M HNO 3 ). This ligand showed a distribution ratio ∼ 2 at 0.5M HNO 3 and stripping was carried out with a mixture of N 2 H 4 (0.2M), HNO 3 (0.6M) and oxalic acid (0.1M). In diamide based solvents choice of spacer between two amide groups is important as the presence of coordinating group in the spacer may further augment its selectivity in metal ion extraction. This has been substantiated in the case of phenanthroline based diamides used in fuel reprocessing. Recently, triarylpyridine based ligands has generated interest as fluorophores for making metal ion chemo-sensors. Keeping in view of special attributes of heterocycle spacered diamides, we designed and synthesized a new class of diamides with 2,4,6-triarylpyridine as a spacer wherein amide functions are anchored in the aromatic rings at 2- and 6-positions for its use as solvent in nuclear fuel reprocessing. The triarylpyridine spacered diamide (TAP-diamide) was synthesized from 2,6-bis(3-hydroxyphenyl)-4-phenylpyridine using classical synthetic methodologies and its extraction potential was evaluated in the separation of Pu and other relevant metal ions including Pu after long term storage. Higher D Pu and separation factors (higher than the reported values for Pu with TAP-diamide using nitrobenzene as diluent over Am, Eu, Th, Zr were observed. However, due to toxicity of nitrobenzene, efforts are on to modify the structure of diamide so that dodecane/phase modifier can be used as a diluent towards Pu extraction. Following is the predominant

  1. Rapid determination of environmental plutonium in large water samples by means of manganese dioxide Co-precipitation and extraction chromatographic separation

    International Nuclear Information System (INIS)

    Sidhu, R.S.; Hoff, P.

    1999-01-01

    Plutonium activity determinations in environmental water samples are routinely performed in many laboratories. Due to the low plutonium concentrations and the complexity of the plutonium aqueous chemistry, these analysis involve cumbersome preconcentration and separation procedures and long measurement times. We describe a procedure where MnO 2 (s) is used as scavenger to preconcentrate Pu prior to separation by the transuranium specific extraction chromatographic resin TRU-Resin. The ability of MnO 4 - /MnO 2 (s) to destroy organic matter and oxidise plutonium is combined with the specific behaviour of the TRU-resin for transuranium elements. The method facilitates a rapid preconcentration and separation of plutonium. With the use of this procedure, the laboratory work on one sample can be performed in one day with minimum attention. The overall yields from a 200 litre fresh- or seawater sample to a measurable Pu source are between 70-85%. (orig.)

  2. Self-Radiolysis of Tritiated Water: Experimental Study and Simulation

    International Nuclear Information System (INIS)

    Heinze, Sylver; Stolz, Thibaut; Ducret, Didier; Colson, Jean-Claude

    2005-01-01

    Radioactive decay of tritium contained in tritiated water leads to the production of gaseous helium and, through self-radiolysis, to the formation of molecular hydrogen and oxygen. For safety management of tritiated water storage, it is essential to be able to predict pressure increase resulting from this phenomenon. The present study aims to identify the mechanisms that take place in self-radiolysis of chemically pure liquid tritiated water. The evolution of the concentration of hydrogen and oxygen in the gas phase of closed vessels containing tritiated water has been followed experimentally. Simulation of pure water radiolysis has been carried out using data from the literature. In order to fit experimental results, simulation should take into account gas phase recombination reaction between hydrogen and oxygen. A simplified system has been extracted from the complete chemical system used to simulate radiolysis. This system allows identifying the basic mechanisms that are responsible for tritiated water self-radiolysis

  3. Stop plutonium; Stop plutonium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-02-01

    This press document aims to inform the public on the hazards bound to the plutonium exploitation in France and especially the plutonium transport. The first part is a technical presentation of the plutonium and the MOX (Mixed Oxide Fuel). The second part presents the installation of the plutonium industry in France. The third part is devoted to the plutonium convoys safety. The highlight is done on the problem of the leak of ''secret'' of such transports. (A.L.B.)

  4. Selective extraction of plutonium from nitric acid medium by bifunctional polyethersulfone beads for quantification with thermal ionisation mass spectrometry

    International Nuclear Information System (INIS)

    Paul, Sumana; Aggarwal, S.K.; Pandey, A.K.

    2015-01-01

    Polyethersulfone (PES) magnetic beads were prepared by phase inversion technique. The beads were grafted with two monomers, viz. 2-hydroxyethylmethacrylate phosphoric acid (HEMP) and (3-acrylamidopropyl)trimethyl ammonium chloride (AMAC), by photo-induced free radical polymerization. Effect of different HNO 3 concentrations on the sorption profiles of Am(III) and Pu(IV) was studied using the grafted PES beads. The beads were found to extract plutonium quantitatively from high nitric acid medium (3-8 M). The effect of presence of competing actinide, e.g. U(VI), on the sorption of Pu(IV) was also studied. (author)

  5. The production control laboratories of the plutonium extraction Plant at Marcoule. Six years operating experience: 1957 - 1963

    International Nuclear Information System (INIS)

    Fontaine, A.

    1964-01-01

    In this paper, the author attempts to sum up the conditions prevailing, after six years of operation, in the Laboratories of the Plutonium Extraction Plant. The origins and objectives are briefly reviewed, the technology and staff recruitment policy are examined, and progress made is shown. The methods used as well as the scope of application and limits imposed at the present state are considered. Past achievements and further possibilities in the next future are examined. An attempt has been made to bring out the outlooks for the more distant future and to investigate the conditions required for the successful carrying out of the program. (author) [fr

  6. Primary processes during water radiolysis

    International Nuclear Information System (INIS)

    Pikaev, A.K.

    1980-01-01

    Briefly reviewed are investigations of primary process mechanism taking place during radiolysis of water and similar systems, executed by direct and indirect methods. A conclusion is made on the important role of the water structure during radiolysis of aqueous solutions of some substances. A necessity to take account of this factor during consideration of radiolysis theoretical models is pointed out

  7. Detection of {alpha} particles using semiconductors. Application to the control of plutonium extraction; Detection des particules {alpha} par semiconducteurs application au controle de l'extraction du plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Tanguy, J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1968-03-01

    A study is made of a particles produced by thick sources, using either diffused junction or surface barrier semiconductor detectors for controlling continuously the plutonium extraction process. For this, a presenting apparatus is described in which the solutions to be analyzed flow in contact with the detector protected by a thin mica membrane. A method is described which gives a precise recording of the spectra and which thus allows the separation of two or more {alpha} emitters present in the same solution. This method has been applied to the measurement of {sup 239}Pu in the the presence of {sup 241}Am with an accuracy of {+-}5 per cent. In the second part of the report is considered the detection of plutonium in solutions of {beta} - {gamma} emitting fission products. Pile-up is reduced by using a fast amplification chain associated to totally depleted thin detectors. Under these conditions a few mg of {sup 239}Pu can be detected in solutions of fission products having an activity of 100 curies/liter. A method is given for discriminating {alpha} and {beta} particles, it is based on the difference in the collection times for the charges liberated by these particles in the detector. (author) [French] On etudie la detection de particules {alpha} issues de sources epaisses par detecteurs semiconducteurs a jonction diffusee ou a barriere de surface pour le controle continu du procede d'extraction du plutonium. A cet effet on decrit un appareil presentateur dans lequel les solutions a analyser circulent au contact du detecteur protege par une membrane mince de mica. On decrit une methode qui permet par le trace precis des spectres de separer deux ou plusieurs emetteurs {alpha} presents dans une meme solution. Cette methode a ete appliquee a la mesure du {sup 239}Pu en presence de {sup 241}Am avec une precision de {+-} 5 pour cent. Dans la deuxieme partie on traite de la detection du plutonium dans des solutions de produits de fission emetteurs {beta} and {gamma

  8. Distribution and identification of Plutonium(IV) species in tri-n-butyl phosphate/HNO3 extraction system containing acetohydroxamic acid

    International Nuclear Information System (INIS)

    Tkac, P.; Paulenova, A.; Vandegrift, G.F.; Krebs, J.F.

    2009-01-01

    There was a significant research progress achieved with the aim to modify conventional PUREX process by stripping of plutonium from the tri-n-butyl phosphate (TBP) extraction product in the form of non-extractable complexes upon addition of back-hold complexation agents. The present paper reports effects of such salt-free complexant, acetohydroxamic acid (HAHA), on distribution ratio of Pu(IV) under wide concentration of nitric acid and additional nitrate. General formula of plutonium species present in the organic phase can be described as Pu(OH) x (AHA) y (NO3) 4-x-y x 2TBP x wHNO 3 . (author)

  9. Empirical equations of the solvent extraction of the energetic inputs, uranium and plutonium, calculated by using the program Microsoft Excel

    International Nuclear Information System (INIS)

    Bento, Dercio Lopes

    2006-01-01

    PUREX is one of the purification process for irradiated nuclear fuel. In the flowchart the program uses various uranium and plutonium extraction phases by using organic solvent contained in the aqueous phase obtained in the dissolution of the fuel element. A posterior extraction U and Pu are changed to the aqueous phase. So it is fundamental to know the distribution coefficient (dS), at the temperature (tc), of the substances among the two immiscible phases, for better calculation the suitable flowchart. A mathematical model was elaborated based on experimental data, for the calculation of the dS and applied to a referential band of substance concentrations in the aqueous phase (xS) and organic (yS). By using the program Excel, we personalized the empirical equations calculated by the root mean square. The relative deviation, among the calculated values and the experimental ones are the standards

  10. Proton Pulse Radiolysis

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, H C; Nilsson, G; Reitberger, T; Thuomas, K A

    1973-03-15

    A 5 MeV proton accelerator (Van de Graaff) has been used for pulse radiolysis of a number of organic gases and the transient spectra obtained from the alkanes methane, ethane, propane, n-butane and neopentane have tentatively been assigned to alkyl radicals. Some methodological aspects of this new technique are discussed

  11. Rapid and simultaneous determination of neptunium and plutonium isotopes in environmental samples by extraction chromatography using sequential injection analysis and ICP-MS

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2010-01-01

    plutonium and neptunium in three reference materials were in agreement with the recommended or literature values at the 0.05 significance level. The developed method is suitable for the analysis of up to 10 g of soil and 20 g of seaweed samples. The extraction chromatographic separation within the SI system......This paper reports an automated analytical method for rapid and simultaneous determination of plutonium isotopes (239Pu and 240Pu) and neptunium (237Np) in environmental samples. An extraction chromatographic column packed with TrisKem TEVA® resin was incorporated in a sequential injection (SI...... for a single sample takes less than 1.5 h. As compared to batchwise procedures, the developed method significantly improves the analysis efficiency, reduces the labor intensity and expedites the simultaneous determination of plutonium and neptunium as demanded in emergency actions....

  12. Comparison of sample preparation methods for reliable plutonium and neptunium urinalysis using automatic extraction chromatography

    DEFF Research Database (Denmark)

    Qiao, Jixin; Xu, Yihong; Hou, Xiaolin

    2014-01-01

    This paper describes improvement and comparison of analytical methods for simultaneous determination of trace-level plutonium and neptunium in urine samples by inductively coupled plasma mass spectrometry (ICP-MS). Four sample pre-concentration techniques, including calcium phosphate, iron......), it endows urinalysis methods with better reliability and repeatability compared with co-precipitation techniques. In view of the applicability of different pre-concentration techniques proposed previously in the literature, the main challenge behind relevant method development is pointed to be the release...

  13. Upgrading a 1944 plutonium-extraction plant to a modern decontamination facility

    International Nuclear Information System (INIS)

    Wills, C.E.; Millikin, R.M.; Cruz, E.A.

    1993-10-01

    The Hanford Site, located in south-central Washington State, is currently undergoing extensive modifications as its mission changes from defense material production to one of waste management and environmental restoration. Starting in World War II, Hanford's mission for over four decades was the production of plutonium for defense needs. With the removal of such defense requirements over the last several years, the Hanford Site has refocused its efforts on the issues of cleanup and safety. The T Plant Complex is the first of the existing facilities to begin conversion from the old mission to the new. This conversion process and associated problems are described

  14. Comparison of extraction chromatography and a procedure based on the molecular recognition method as separation methods in the determination of neptunium and plutonium radionuclides

    International Nuclear Information System (INIS)

    Strisovska, Jana; Galanda, Dusan; Drabova, Veronika; Kuruc, Jozef

    2012-01-01

    The potential of various types of sorbents for separation of radionuclides of plutonium and neptunium were examined. Extraction chromatography and a procedure based on the molecular recognition method were used for the separation. The suitability of the various sorbent types and brands for this purpose was determined. (orig.)

  15. Electrons in water radiolysis

    International Nuclear Information System (INIS)

    Laverne, J.A.; Pimblott, S.M.

    2006-01-01

    The hydrated electron is the main reducing species produced in the radiolysis of water. Many studies have examined its reactivity using pulsed radiolysis techniques and competition kinetics. Data bases list hundreds of rate coefficients for reaction of the hydrated electron with substances ranging from inorganic ions like nitrate to biopolymers like DNA. Although the chemistry of the hydrated electron is often examined, its mechanism of formation and variation in yield are considerable less known, especially under extreme conditions such as in high temperature water or with heavy ion radiolysis. This work will examine various aspects of the radiation chemistry of the hydrated electron beginning with the generation of secondary electrons in primary energy loss events during the passage of ionizing radiation to the radiolytic yields of the hydrated electron produced by different types of radiation. Ion radiation is a 'white light source.' Energy losses range from the minimum excitation energy of the medium up to the kinematic maximum determined by the collision parameters. However, certain energy loss events are more probable than others. The dipole oscillator strength distributions of media essentially give the probability of energy loss events in collisions with no momentum transfer. Dipole oscillator distributions have been constructed from experimental data for a wide variety of materials including all the phases of water. Calculations using cross sections based on dipole oscillator distributions show that the most probable energy loss event in water is only about 20 eV with an average value closer to 60 eV. The preponderance of energy loss events of less than 100 eV means that many low energy electrons are formed by the passage of a single ion. Low energy electrons have short mean free paths and they remain in the vicinity of the primary energy loss events. The spatial distribution of these low energy electrons defines the radial track structure of the incident

  16. Pulse radiolysis of gases

    International Nuclear Information System (INIS)

    Nielsen, O.J.

    1984-04-01

    The pulse radiolysis equipment and technique are described and its relevance to atmospheric chemistry is discussed. Pulse radiolysis of a number of different chemical systems have been used to check the validity of the proposed mechanisms: 1) The hydrogen atom yield in the pulse radiolysis of H 2 was measured by four independent calibration techniques, using reactions of H with O 2 , C1NO, and HI. The H atom yield was compared with O 2 yields in pure O 2 and in O 2 /SF 6 mixtures which lead to a value G(H) = 17.6. The rate constants at room temperature of several reactions were determined. 2) OH radical reactions with tetraalkyllead at room temperature and with ethane, methane, and a series of C1- and F-substituted methanes at 300-400 K were studied. Arrhenius parameters, A and Esub(a), were determined for several reactions. The lifetime of Pb(CH 3 ) 4 and Pb(C 2 H 5 ) 4 in ambient air is estimated. CF 2 C1 2 was found to be a very efficient third body, M, in the reaction OH + OH + M arrow H 2 O 2 + M. 3) In the H 2 S systems the HS extinction coefficient at 3242 AA was determined to 9.5 x 10 2 cm -1 mol -1 . Four rate constants at room temperature were determined. (author)

  17. Plutonium-236 traces determination in plutonium-238 by α spectrometry

    International Nuclear Information System (INIS)

    Acena, M.L.; Pottier, R.; Berger, R.

    1969-01-01

    Two methods are described in this report for the determination of plutonium-236 traces in plutonium-238 by a spectrometry using semi-conductor detectors. The first method involves a direct comparison of the areas under the peaks of the α spectra of plutonium-236 and plutonium-238. The electrolytic preparation of the sources is carried out after preliminary purification of the plutonium. The second method makes it possible to determine the 236 Pu/ 238 Pu ratio by comparing the areas of the α peaks of uranium-232 and uranium-234, which are the decay products of the two plutonium isotopes respectively. The uranium in the source, also deposited by electrolysis, is separated from a 1 mg amount of plutonium either by a T.L.A. extraction, or by the use of ion-exchange resins. The report ends with a discussion of the results obtained with plutonium of two different origins. (authors) [fr

  18. Plutonium fires; Incendies de plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Mestre, E.

    1959-06-23

    The author reports an information survey on accidents which occurred when handling plutonium. He first addresses accidents reported in documents. He indicates the circumstances and consequences of these accidents (explosion in glove boxes, fires of plutonium chips, plutonium fire followed by filter destruction, explosion during plutonium chip dissolution followed by chip fire). He describes hazards associated with plutonium fires: atmosphere and surface contamination, criticality. The author gives some advices to avoid plutonium fires. These advices concern electric installations, the use of flammable solvents, general cautions associated with plutonium handling, venting and filtration. He finally describes how to fight plutonium fires, and measures to be taken after the fire (staff contamination control, atmosphere control)

  19. Study of a plutonium substitute for the reducing back-extraction in low flow rate contactors; Etude d'un substitut du plutonium pour la desextraction reductrice dans des contacteurs a faible temps de sejour

    Energy Technology Data Exchange (ETDEWEB)

    Morell, M

    1998-12-16

    The aim of this work is to define and carry out a non-radioactive redox chemical system, similar to those of the plutonium, in a reducing back-extraction operation. In the first part, we have replaced our study within the context of the spent fuels. The choice of cerium as a plutonium substitute is justified and the used centrifugal drier described. The current process is presented and the set problem explained. The experimental study concerns essentially the research of reducers of the chosen substitute, the stability of ceric solutions, the measurement of distribution coefficients and the study of redox chemical kinetics. In the last part, are given the used simulation tools (development of a mathematical model in a first step and adaptation of the PAREX code in the second step) and the results of their comparison with the experimental data.

  20. Study of a plutonium substitute for the reducing back-extraction in low flow rate contactors; Etude d'un substitut du plutonium pour la desextraction reductrice dans des contacteurs a faible temps de sejour

    Energy Technology Data Exchange (ETDEWEB)

    Morell, M

    1998-12-16

    The aim of this work is to define and carry out a non-radioactive redox chemical system, similar to those of the plutonium, in a reducing back-extraction operation. In the first part, we have replaced our study within the context of the spent fuels. The choice of cerium as a plutonium substitute is justified and the used centrifugal drier described. The current process is presented and the set problem explained. The experimental study concerns essentially the research of reducers of the chosen substitute, the stability of ceric solutions, the measurement of distribution coefficients and the study of redox chemical kinetics. In the last part, are given the used simulation tools (development of a mathematical model in a first step and adaptation of the PAREX code in the second step) and the results of their comparison with the experimental data.

  1. Radiolysis of chitosan derivatives exhibiting antimutagenic activity

    International Nuclear Information System (INIS)

    Aleksandrova, V.A.; Kuzina, S.I.; Shilova, I.A.; Mikhajlov, A.I.

    2006-01-01

    The radiolysis of antimutagens extracted from natural biopolymer chitosan was studied by the EPR. The radiolysis of test samples of biopolymers and gallic acid was performed in vacuum at 77 K using a 60 Co γ-radiation source, with radiation doses 50 kGy. It was shown that addition of gallic acid (2 mol %) to quaternized chitosan results in a 2.5-fold decrease in the radiation-chemical yield of radicals and a nearly complete inhibition of the formation of ion radicals. Gallic acid units likely play the role of a stabilizer that protects the polycation from radiation damage and, hence, the structure of the cationogenic units from changes, thereby improving the antimutagenic properties of the system [ru

  2. Study of the physico-chemical agents influencing uranium and plutonium extraction by tributylphosphate in nitric media; Etude des facteurs physico-chimiques intervenant dans l'extraction de l'uranium et du plutonium par le phosphate de tributyle en milieu nitrique

    Energy Technology Data Exchange (ETDEWEB)

    Tarnero, M [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-03-01

    The following different factors are reviewed: tributylphosphate concentration, nitric acid concentration, influence of non-extractable nitrates, simultaneous presence of uranium and plutonium, presence of some different ions, temperature, nature of the diluent, addition of a second active solvent (synergic or antagonistic effect), tributylphosphate and diluent degradation. (author) [French] On passe en revue les differents facteurs suivants: concentration en phosphate de tributyle, concentration en acide nitrique, influence des nitrates non-extractibles, presence simultanee d'uranium et de plutonium, presence d'ions divers, addition d'un second solvant actif (effet de synergie, ou effet antagoniste), degradation du phosphate de tributyle et des solvants inertes. (auteur)

  3. Radiolysis of other organic compounds

    International Nuclear Information System (INIS)

    Pikaev, A.K.

    1986-01-01

    Peculiarities of radiolysis of organic halogen, phosphorus, sulfur and nitrogen (including amines, amides, nitriles et al.) compounds in liquid phase are discussed. Intermediate and stable finish products of radiolysis of the given compounds, properties and radiochemical yields of these products are considered

  4. Stop plutonium

    International Nuclear Information System (INIS)

    2003-02-01

    This press document aims to inform the public on the hazards bound to the plutonium exploitation in France and especially the plutonium transport. The first part is a technical presentation of the plutonium and the MOX (Mixed Oxide Fuel). The second part presents the installation of the plutonium industry in France. The third part is devoted to the plutonium convoys safety. The highlight is done on the problem of the leak of ''secret'' of such transports. (A.L.B.)

  5. Gas adsorption during storage of plutonium dioxide powders

    International Nuclear Information System (INIS)

    Cuillerdier, C.; Cossonnet, C.; Germain, M.

    1984-10-01

    Adsorption phenomena occuring in plutonium dioxide containers are studied for the determination of safe conditions for storage and transportation of plutonium dioxide powders. Adsorption on dried PuO 2 of air individual gases, influence of powder isotopic composition, chemisorption, effect of moisture are determined. Adsorption of dry air obeys an Elovich's law for its kinetics it is greatly exchange by α radiolysis. Pressure in the container can be reduced by storage under dry inert gas (Ar), decreasing the PuO 2 load and using powder containing preadsorbed water or wet air then radiolysis may occur (H 2 formation)

  6. Advances in the sample preparation and the detector for a combined solvent extraction-liquid scintillation method of low-level plutonium measurement

    International Nuclear Information System (INIS)

    Perdue, P.T.; Christian, D.J.; Thorngate, J.H.; McDowell, W.J.; Case, G.N.

    1976-07-01

    A combined solvent extraction-liquid scintillation technique, developed at Oak Ridge National Laboratory (ORNL), has many possible applications to the determination of low levels of plutonium and other alpha-emitting nuclides. Using these procedures, plutonium can be extracted from biological or environmental samples and introduced directly into a liquid scintillator. Quenching of the scintillator is thus minimized so that spectroscopic techniques may be employed. Existing chemical procedures and counting equipment were reviewed and improved. Purification of the di(2-ethylhexyl)phosphoric acid (used as the actinide extractant) was found necessary. Destruction of organic material in the sample and control of the valence state of plutonium were found to be major sources of irreproducibility. Methods were developed to allow samples separated with commonly used ion exchange techniques to be extracted into the scintillator. Comparisons were made of a wide variety of the components and parameters of the detector system to find the best combination of pulse-height resolution and pulse-shape discrimination. When a single phototube was used, optimum performance was obtained using a hemispherical reflector-sample holder viewed sideways by an RCA 8575 photomultiplier tube used in conjunction with a special integrating preamplifier and a good quality linear amplifier that used delay lines to shape the pulses

  7. Radiolysis of starch

    International Nuclear Information System (INIS)

    Raffi, J.; Saint-Lebe, L.; Berger, G.

    1978-01-01

    In the first part of the paper the results of work on the identification and determination of the gamma ( 60 Co) radiolysis products of maize starch are brought together and, wherever possible, a balance drawn up by chemical class. The second part of the paper deals with the main parameters governing radiolysis: dose, irradiation temperature and atmosphere, water content and the conditions under which the irradiated starch is stored. The third part, devoted to the mechanisms believed to be involved, contains the following conclusions: (a) the formation of radiation-induced products with a carbon skeleton probably results from a breaking of the -C-O-C- chains with rearrangement of the radicals and/or a reaction involving the water and the oxygen - the oxygen has an activating effect which does not fundamentally modify the mechanism, whereas the effect of the water is more complex and varies according to the product; (b) the formation of hydrogen peroxide probably implies the addition of atmospheric oxygen to the radiation-induced hydrogen atoms in the water or to the organic radicals obtained by abstraction of a hydrogen from the starch. Lastly, the different methods envisaged for confirming or improving the mechanistic hypotheses are discussed. (author)

  8. Plutonium Plant, Trombay

    International Nuclear Information System (INIS)

    Yadav, J.S.; Agarwal, K.

    2017-01-01

    The journey of Indian nuclear fuel reprocessing started with the commissioning of Plutonium Plant (PP) at Trombay on 22"n"d January, 1965 with an aim to reprocess the spent fuel from research reactor CIRUS. The basic process chosen for the plant was Plutonium Uranium Reduction EXtraction (PUREX) process. In seventies, the plant was subjected to major design modifications and replacement of hardware, which later met the additional demand from research reactor DHRUVA. The augmented plutonium plant has been operating since 1983. Experience gained from this plant was very much helpful to design future reprocessing plant in the country

  9. Plutonium controversy

    International Nuclear Information System (INIS)

    Richmond, C.R.

    1980-01-01

    The toxicity of plutonium is discussed, particularly in relation to controversies surrounding the setting of radiation protection standards. The sources, amounts of, and exposure pathways of plutonium are given and the public risk estimated

  10. Plutonium controversy

    Energy Technology Data Exchange (ETDEWEB)

    Richmond, C.R.

    1980-01-01

    The toxicity of plutonium is discussed, particularly in relation to controversies surrounding the setting of radiation protection standards. The sources, amounts of, and exposure pathways of plutonium are given and the public risk estimated. (ACR)

  11. Radiolysis of polytetrafluoroethylene

    International Nuclear Information System (INIS)

    Ferreira, Max Passos; Ferreira, Roberta Viana; Verly, Rodrigo Moreira

    2007-01-01

    Polytetrafluoroethylene is a linear polymer with structure: -[-CF 2 -CF 2 -] n -. Due to its singular properties, it is ideal for use at high temperatures and in chemically aggressive environments. It is extremely sensitive to ionizing radiation and is quickly degraded. PTFE radiolysis has been extensively studied. However, despite the many published papers, its degradation mechanism remains much uncertain. The degradation of polytetrafluoroethylene by γ irradiation yields perfluorinated carboxylic acids, olefin mixtures, and paraffins with different molecular weights. This process is a new alternative for the synthesis of aliphatic perfluorinated compounds used as intermediates for obtaining special products such as fluoro surfactants, electrical materials, special products for the textile industry, etc. PTFE scraps were irradiated with a uniform source of 60 Co gamma rays in oxygen atmosphere with a dose of 3 MGy. The radiolysis of PTFE yielded a water soluble material (probably fluorinated hydrocarbons with low molecular weight and main chains with 10-20 carbon atoms) and a water insoluble brittle polymeric material. Spectroscopy analysis in the infrared region of irradiated and non-irradiated PTFE were carried out. X-ray diffractometry pointed to changes in the crystalline structure of PTFE; scanning electron microscopy indicated alterations in samples irradiated under different conditions. Mass spectrometry was also used to identify the compounds formed after sample irradiation. Comparison of irradiated and non-irradiated FTIR spectra showed the formation of bands at 3450 cm -1 , associated with the O-H stretching, and at 1631 cm -1 , associated with the C=O stretching. The bands are characteristic of carboxylic acid, which indicates its formation in irradiated PTFE. (author)

  12. Radioanalytical determination of plutonium and americium using ion exchange and extraction chromatography technique in urine

    International Nuclear Information System (INIS)

    Santhanakrishnan, V.; Sreedevi, K.R.; Rajaram, S.; Ravi, P.M.

    2011-01-01

    The use of anion exchange chromatography for the separation of Pu and extraction chromatography technique for the separation of Am from urine samples was studied. In the earlier method, Pu separation was carried out by anion exchange chromatography followed by Am separation by cation exchange chromatography. The chemical recovery of Am obtained by cation exchange separation method was inconsistent and low in the range 30-70%. In this study, the average Pu recovery obtained using anion exchange chromatography was 89.2 with standard deviation of 10.4 and the average Am recovery obtained using extraction chromatography with TRU resin was 77.4 with standard deviation of 14.8. Moreover, Am separation could be completed within three hours using the TRU column compared to two days that were required for the cation exchange chromatography. (author)

  13. Uranium and plutonium extraction by N,N-dialkyl-amides using multistage mixer-settler extractors

    Energy Technology Data Exchange (ETDEWEB)

    Ban, Y.; Hotoku, S.; Tsutsui, N.; Suzuki, A.; Tsubata, Y.; Matsumura, T.

    2016-07-01

    N,N-Dialkyl-amides (mono-amides) are known as extractants for U and Pu, and many studies have been carried out mainly by single-stage batch method. We have focused on two mono amides: N,N-di(2-ethylhexyl)-2,2-dimethylpropanamide (DEHDMPA) and N,N-di(2-ethylhexyl)butanamide (DEHBA), and proposed a multistage extraction process for recovering U and Pu by these mono-amides. A continuous counter-current experiment was carried out to demonstrate the validity of this process. This process consisted of two cycles, and the first cycle and the second cycle employed DEHDMPA and DEHBA as extractants, respectively. The feed solution for the first cycle was 5.1 mol/dm{sup 3} (M) nitric acid containing 0.92 M U, 1.6 mM Pu, and 0.6 mM Np. The raffinate collected in the first cycle was used as the feed for the second cycle. The ratios of U recovered in the U fraction and U-Pu fraction were 99.1% and 0.8%, respectively, and the ratios of U in the used solvents were <0.04%. The ratio of Pu recovered in the U-Pu fraction was 99.7%, and the ratio of Pu in the used solvents was in the order of 10{sup -3} - 10{sup -4}%. The concentration ratio of U with respect to Pu in the U-Pu fraction was 9, and this indicated that Pu was not isolated. The decontamination factor of U with respect to Pu in the U fraction was obtained as 4.5*10{sup 5}. These results supported the validity of the proposed process. (authors)

  14. Separation of gallium and actinides in plutonium nuclear materials by extraction chromatography

    International Nuclear Information System (INIS)

    Eitrheim, E.S.; Knight, A.W.

    2015-01-01

    Analysis of stable gallium in nuclear materials has applications in nuclear fuel characterization and nuclear forensics. The use of positron-emitting gallium isotope 68 Ga as a tracer for Ga recoveries for analyses in materials containing actinides was explored. A radiochemical method for the separation of Ga, Pu, U, Th, and Am using commercially-available extraction chromatography resins was developed and evaluated. The method effectively allows precise determination of Ga yield (97 ± 3 %) in the analysis of stable Ga (spike recovery 101 ± 1 %) and radioactive Pu (radiochemical yield, 82 ± 10 %; spike recovery, 96 ± 3 %), while also providing pure elemental fractions of other actinides relevant to materials encountered in the analysis Pu-containing materials. (author)

  15. Isoparaffinic diluents for tri-n-butyl phosphate. Chemical, radiation-chemical stability, effect on tetravalent plutonium and thorium extraction

    International Nuclear Information System (INIS)

    Renard, E.V.; Pyatibratov, Yu.P.; Neumoev, N.V.; Chizhov, A.A.; Kulikov, I.A.; Gol'dfarb, Yu.Ya.; Sirotkina, I.G.; Semenova, T.I.

    1989-01-01

    By means of catalytic hydroisomerization of the n-paraffinic raw material in a reactor using alumino-platinum catalysts, there was attained a 45-90% degree of conversion of n-paraffins into branched iso-paraffins with mono- and dimethyl structure. From a batch of extensively isomerized n-paraffins, by carrying out the operations of distillation of the light (benzine) fraction, dearomatization, de-n-paraffinization and fractional distillation on a rectification column, isoparaffinic (99%) concentrates were obtained with a constant molecular weight, from iso-C 10 to isoC 15 . The solubility of plutonium and thorium nitrates in 30% solutions of TBP in iso-paraffins (mixtures of iso-paraffins with the same number of C-atoms) increases with decrease in the molecular weight of the iso-paraffin; a system with a 30% TBP in a mixture of iso-decanes practically does not stratify (∼104 g Pu/liter, 22-25 degree C). Nevertheless, a twofold increase (compared with NP) of the maximally permissible (up to the formation of the third phase) concentration, is attained when iso-paraffins are introduced into NP with a similar molecular composition in a 1:1 ratio. With respect to the main requirements demanded of diluents for radiochemical extractional operations, such as density, viscosity, boiling point, flash point, and freezing point, the chemical stability and radiation resistance, content of radioruthenium and radiozirconium, rate of stratification of two-phase systems, the synthetic iso-paraffin-containing solvents are as suitable as n-paraffins

  16. A comparative study of thermodynamics in synergistic extraction of hexavalent plutonium by HTTA and HPMBP using mono- and bi-functional neutral donors

    International Nuclear Information System (INIS)

    Lohithakshan, K.V.; Mithapara, P.D.; Pai, S.A.; Aggarwal, S.K.

    1996-01-01

    Synergistic extraction of hexavalent plutonium was studied from HNO 3 medium (0.05 M) with HTTA and various neutral donors viz. DPSO, TBP, TOPO (monofunctional) and DBDECMP, DHDECMP, CMPO (bifunctional) using benzene as a diluent. Thermodynamic parameters (Δ G, Δ H, Δ S) were evaluated at 298 K from the experiments performed at four fixed temperatures in 288 to 318 K range. These were compared with the corresponding values reported earlier for Pu(VI) + HPMBP + neutral donor system. The net negative enthalpy changes with HTTA were observed to be low as compared to those with HPMBP. The net entropy changes were found to be either negligibly small (in cases of DPSO, TBP, DBDECMP, DHDECMP) or positive (in cases of CMPO, TOPO) with HTTA in comparison to large negative values with HPMBP. These results were interpreted in terms of different organic phase adduct formation reaction mechanisms i.e. substitution in HTTA vs. addition in HPMBP. Further, the lower net enthalpy changes with HTTA were explained due to a part of the energy used in release of water molecules bonded to plutonium in the plutonium chelate. (orig.)

  17. Production of Plutonium Metal from Aqueous Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Orth, D.A.

    2003-01-16

    The primary separation of plutonium from irradiated uranium by the Purex solvent extraction process at the Savannah River Plant produces a dilute plutonium solution containing residual fission products and uranium. A cation exchange process is used for concentration and further decontamination of the plutonium, as the first step in the final preparation of metal. This paper discusses the production of plutonium metal from the aqueous solutions.

  18. Measurement of total alpha activity of neptunium, plutonium, and americium in highly radioactive Hanford waste by iron hydroxide precipitation and 2-heptanone solvent extraction

    International Nuclear Information System (INIS)

    Maiti, T.C.; Kaye, J.H.

    1992-06-01

    An improved method has been developed to concentrate the major alpha-emitting actinide elements neptunium, plutonium, and americium from samples with high salt content such as those resulting from efforts to characterize Hanford storage tank waste. Actinide elements are concentrated by coprecipitation of their hydroxides using iron carrier. The iron is removed by extraction from 8M HCI with 2-heptanone. The actinide elements remain in the aqueous phase free from salts, iron, and long-lived fission products. Recoveries averaged 98 percent

  19. Testing requirements for SCWR radiolysis

    International Nuclear Information System (INIS)

    Guzonas, D.; Stuart, C.; Jay-Gerin, J.-P.; Meesungnoen, J.

    2010-01-01

    The Generation IV supercritical water-cooled reactor (SCWR) designs under consideration would operate at ∼430-625 o C and 25 MPa, i.e., well beyond the thermodynamic critical point of water. Supercritical (light/heavy) water (SCW)-cooled reactors would enable thermodynamic cycle efficiencies as high as ∼44% (versus ∼33% for existing water reactors), thus generating lower-cost electricity. The purpose of this report is to survey the literature on SCW radiolysis, describe the recent modeling performed at the Universite de Sherbrooke, and to broadly outline the testing required to develop a benchmarked SCW radiolysis model. (author)

  20. A computerized pulse radiolysis system

    International Nuclear Information System (INIS)

    Eriksen, T.E.; Lind, J.; Reitberger, T.

    1976-01-01

    A computer based pulse radiolysis system for gathering and handling of transient optical absorption and electric conductivity data is presented. The system has been developed around a Biomation 8100 transient recorder and a PDP 11/40 (Digital Equipment Corp) computer. (author)

  1. Non-gaseous radiolysis products of 6-aminopenicillanic acid and potassium salt of benzylepenicillin

    International Nuclear Information System (INIS)

    Dziegielewski, J.; Jezowska-Trzebiatowska, B.; Siemion, I.Z.

    1974-01-01

    The radiolysis products of 6-aminopenicillanic acid (6-APA) and potassium salt of benzylpenicillin G, irradiated with γ-rays were separated by the extraction methods and chromatographically by the thin-layer method. On the basis of the IR and UV spectroscopic investigations as well as by the NMR and mass spectrometry methods of the radiolysis products, the paths of the radiation decomposition of 6-APA and of penicillin G were determined. (author)

  2. Plutonium controversy

    International Nuclear Information System (INIS)

    Gofman, J.W.

    1976-01-01

    If the world chooses to seek a solution to the energy dilemma through nuclear energy, the element plutonium will become an article of commerce to be handled in quantities of thousands of tonnes annually. Plutonium is a uniquely potent inhalation carcinogen, the potential induction of lung cancer dwarfing other possible toxic effects. For reasons to be presented here, it is the author's opinion that plutonium's carcinogenicity has been very seriously underestimated. If one couples the corrected carcinogenicity with the probable degree of industrial containment of the plutonium, it appears that the commercialization of a plutonium-based energy economy is not an acceptable option for society. Sagan's statement that ''the experience of 30 years supports the contention that plutonium can be used safely'' is manifestly indefensible. No meaningful epidemiological study of plutonium-exposed workers for that 30-year period has ever been done. Since thousands of those possibly exposed have left the industry and are not even available to follow-up, it is doubtful that any meaningful study of ''the experience of 30 years'' will ever be accomplished

  3. Plutonium recovery from carbonate wash solutions

    International Nuclear Information System (INIS)

    Gray, J.H.; Reif, D.J.; Chostner, D.F.; Holcomb, H.P.

    1991-01-01

    540Periodically higher than expected levels of plutonium are found in carbonate solutions used to wash second plutonium cycle solvent. The recent accumulation of plutonium in carbonate wash solutions has led to studies to determine the cause of that plutonium accumulation, to evaluate the quality of all canyon solvents, and to develop additional criteria needed to establish when solvent quality is acceptable. Solvent from three canyon solvent extraction cycles was used to evaluate technology required to measure tributyl phosphate (TBP) degradation products and was used to evaluate solvent quality criteria during the development of plutonium recovery processes. 1 fig

  4. Summary of TRUEX Radiolysis Testing Using the INL Radiolysis Test Loop

    Energy Technology Data Exchange (ETDEWEB)

    Dean R. Peterman; Lonnie G. Olson; Rocklan G. McDowell; Gracy Elias; Jack D. Law

    2012-03-01

    The INL radiolysis and hydrolysis test loop has been used to evaluate the effects of hydrolytic and radiolytic degradation upon the efficacy of the TRUEX flowsheet for the recovery of trivalent actinides and lanthanides from acidic solution. Repeated irradiation and subsequent re-conditioning cycles did result in a significant decrease in the concentration of the TBP and CMPO extractants in the TRUEX solvent and a corresponding decrease in americium and europium extraction distributions. However, the build-up of solvent degradation products upon {gamma}-irradiation, had little impact upon the efficiency of the stripping section of the TRUEX flowsheet. Operation of the TRUEX flowsheet would require careful monitoring to ensure extraction distributions are maintained at acceptable levels.

  5. Plutonium solubilities

    International Nuclear Information System (INIS)

    Puigdomnech, I.; Bruno, J.

    1991-02-01

    Thermochemical data has been selected for plutonium oxide, hydroxide, carbonate and phosphate equilibria. Equilibrium constants have been evaluated in the temperature range 0 to 300 degrees C at a pressure of 1 bar to T≤100 degrees C and at the steam saturated pressure at higher temperatures. Measured solubilities of plutonium that are reported in the literature for laboratory experiments have been collected. Solubility data on oxides, hydroxides, carbonates and phosphates have been selected. No solubility data were found at temperatures higher than 60 degrees C. The literature solubility data have been compared with plutonium solubilities calculated with the EQ3/6 geochemical modelling programs, using the selected thermodynamic data for plutonium. (authors)

  6. Assesment of Plutonium 238 and Plutonium 239+240 in soils of different agricultural regions of Guatemala

    International Nuclear Information System (INIS)

    Gutierrez Martinez, E.A.

    1998-02-01

    In this report an assesment and measurement of PLUTONIUM 238, PLUTONIUM 239, and PLUTONIUM 240 are made. Samples of cultivated soils in 15 provinces of Guatemala were taken. To separate plutonium isotopes a radiochemical method was made using extraction, precipitation and ionic interchange. By electrodeposition the plutonium was measured using an alpha spectroscopy by PIPS method. The radioactivity ranges from 2.84 mBq/Kg to 36.38 mBq/Kg for plutonium 238, and 8.46 mBq/Kg to 26.61 mBq/Kg for plutonium 239+240

  7. Radiolysis and radiosterilization of drugs

    International Nuclear Information System (INIS)

    Zeegers, F.; Crucq, A.S.; Gibella, M.; Tilquin, B.

    1993-01-01

    Can the absence of increased toxicological danger in irradiated foods be applied with confidence to drugs. The World Health Organization stated that up to 10 kGy there is no toxicological hazard. However, even if the irradiated drugs meet official standards, it would have to be established that any traces of radiolysis product formed are not toxic. All the tests from PHARMACOPEIA are not appropriate to detect the radiolysis and new physicochemical tests have to be used. Chromatographic detection of the radiosterilization of antibiotics may be advantageously used when the pharmaceuticals are not radio-resistant. The main obstacle to practical application is the low sensitivity of the detectors in liquid-liquid chromatography, a re-irradiation of the suspected samples will be necessary after preliminary chromatographic studies. 8 figs

  8. Gamma-radiolysis of benzosubstituted crown ethers

    International Nuclear Information System (INIS)

    Grigor'ev, E.I.; Nesterov, S.V.; Mikhalitsyna, O.V.; Trakhtenberg, L.I.; Myasoedova, T.G.

    1992-01-01

    The products of gamma-radiolysis of benzosubstituted crown ethers, which are distiguished by the size of polyether ring, and alkylsubstituted DB18C6 are studied by the methods of ESR and mass-spectrometry. A mechanism of the radiolysis of the radiolysis of the studied compounds in the solid phase is proposed. It is shown that the prinicple radiolysis process is the rupture of C-O bond resulting in the stabilization of H atoms from group -CH 2 - of polyether ring is realized with a lower probability

  9. The first milligrams of plutonium

    International Nuclear Information System (INIS)

    Goldschmidt, B.

    1996-01-01

    This paper relates the discovery of the different plutonium chemical extraction processes in their historical context. The first experiments started during the second world war in 1942 with the American ''Metallurgical Laboratory'' project which brought together Arthur Compton, Enrico Fermi and Glenn Seaborg. During the same period, a competitive English-Canadian project, the ''Montreal Project'', was carried out to test different plutonium solvent extraction techniques. The author participated in both projects and joined the CEA in 1946, where he was in charge of the uranium and plutonium chemistry. By the end of 1949, his team could isolate the first milligrams of French plutonium from uranium oxide pellets of the ZOE reactor. In the beginning of 1952 he developed with his team the PUREX process. (J.S.)

  10. Isoparaffin diluents for tri-n-butyl phosphate. Chemical, radiation-chemical stability, effect on solvent extraction of tetravalet plutonium and thorium

    International Nuclear Information System (INIS)

    Renard, Eh.V.; Pyatibratov, Yu.P.; Neumoev, N.V.

    1988-01-01

    45-90% conversion degree of n-paraffin into branched isoparaffin with mono- and dimethyl structure is achieved by means of catalytic hydroisomerization of n-paraffin raw material in reactor with alumoplatinum catalyser. Isoparaffin (99%) concentrates with constant molecular mass from iso-C 10 to iso-C 15 are produced of a batch of deeply isomerized n-paraffins. Plutonium and thorum nitrate solubility in 30% TBP solutions in iso-paraffins (iso-paraffin mixtures with similar C atom number) increases with the reduction of iso-paraffin molecular mass; system with 30% TBP in isodecane mixture is practically not stratified (∼ 104 g Pu/l, 22-25 deg C). By the main requirements to diluents for radiochemical extraction operations, including density, viscosity, boiling point flashed and freezines, chemical and radiation stability, radioruthenium and radiozirconium confinement systems, synthetic isoparaffin-containing solvents are as good as n-paraffins

  11. Gamma-radiolysis of organic compounds and alpha-radiolysis of water

    International Nuclear Information System (INIS)

    Christensen, H.

    1978-09-01

    This KBS-report is a collection of five technical reports. Various radiolytic problems in connection with the disposal of high-active waste are dealt with. The English titles of the five reports are: 1) Radiolysis of fulvic acids; 2) Radiolysis of organic compounds in bentonite; 3) α-radiolysis of water during the disposal of fuel without reprocessing; 4) Radiolysis of water during the disposal of unreprocessed spent fuel. Oxidation by hydrogen peroxide; 5) Formation and decomposition of hydrogen peroxide by α-radiolysis. These reports (in Swedish) are attached as Appendices A-E. (author)

  12. Pressurization of Containment Vessels from Plutonium Oxide Contents

    International Nuclear Information System (INIS)

    Hensel, S.

    2012-01-01

    Transportation and storage of plutonium oxide is typically done using a convenience container to hold the oxide powder which is then placed inside a containment vessel. Intermediate containers which act as uncredited confinement barriers may also be used. The containment vessel is subject to an internal pressure due to several sources including; (1) plutonium oxide provides a heat source which raises the temperature of the gas space, (2) helium generation due to alpha decay of the plutonium, (3) hydrogen generation due to radiolysis of the water which has been adsorbed onto the plutonium oxide, and (4) degradation of plastic bags which may be used to bag out the convenience can from a glove box. The contributions of these sources are evaluated in a reasonably conservative manner.

  13. The production control laboratories of the plutonium extraction Plant at Marcoule. Six years operating experience: 1957 - 1963; Les laboratoires de fabrication de l'usine d'extraction du plutonium de Marcoule. Experience des 6 premieres annees de fonctionnement: 1957 - 1963

    Energy Technology Data Exchange (ETDEWEB)

    Fontaine, A [CEA Marcoule, Centre de Production de Plutonium, 30 (France)

    1964-07-01

    In this paper, the author attempts to sum up the conditions prevailing, after six years of operation, in the Laboratories of the Plutonium Extraction Plant. The origins and objectives are briefly reviewed, the technology and staff recruitment policy are examined, and progress made is shown. The methods used as well as the scope of application and limits imposed at the present state are considered. Past achievements and further possibilities in the next future are examined. An attempt has been made to bring out the outlooks for the more distant future and to investigate the conditions required for the successful carrying out of the program. (author) [French] Le present rapport tente, apres 6 ans de vie, de faire le point de la situation des Laboratoires du Service Extraction du Plutonium. Apres un rapide retour sur les origines et les objectifs, apres quelques considerations sur le recrutement et la technologie situant le contexte de leurs progres, nous etudierons les methodes, leurs domaines d'application, leurs limites actuelles. Nous ferons un bilan des realisations et des possibilites pour un avenir proche. Nous tenterons de degager quelques vues plus lointaines et les conditions pour les mener a bonne fin. (auteur)

  14. Air effect on polycarbonate radiolysis

    International Nuclear Information System (INIS)

    Terence, Mauro C.; Araujo, Elmo S.; Guedes, Selma M.L.

    1995-01-01

    The formation and decay of radicals in the radiolysis of new type of polycarbonate (G scission = 0,73) was investigated by electron spin resonance spectroscopy in the presence and absence of air at room temperature. The air does not interfere in the formation of radicals because they are formed as consequence of direct interaction of radiation. But the air interferes in their decays. During the irradiation the air reacts with all isopropyl radicals and with 2/3 of phenoxy + phenyl radicals. (author). 5 refs., 3 figs

  15. CONVERSION OF PLUTONIUM TRIFLUORIDE TO PLUTONIUM TETRAFLUORIDE

    Science.gov (United States)

    Fried, S.; Davidson, N.R.

    1957-09-10

    A large proportion of the trifluoride of plutonium can be converted, in the absence of hydrogen fluoride, to the tetrafiuoride of plutonium. This is done by heating plutonium trifluoride with oxygen at temperatures between 250 and 900 deg C. The trifiuoride of plutonium reacts with oxygen to form plutonium tetrafluoride and plutonium oxide, in a ratio of about 3 to 1. In the presence of moisture, plutonium tetrafluoride tends to hydrolyze at elevated temperatures and therefore it is desirable to have the process take place under anhydrous conditions.

  16. Plutonium (Pu)

    International Nuclear Information System (INIS)

    2002-01-01

    This pedagogical document presents the properties and uses of plutonium: where does it come from, the history of its discovery, its uses and energy content, its recycling and reuse in MOX fuels, its half-life, toxicity and presence in the environment. (J.S.)

  17. The application of radiolysis and analysis of influencing factors

    International Nuclear Information System (INIS)

    Xie Fang; Ha Yiming; Wang Feng

    2008-01-01

    As a branch of radiation technology, radiolysis technology has been developing in recent years. The update research and application of radiolysis is briefly reviewed. The radiolysis in reducing veterinary drug residues in food, processing plant sources products and environmental management are summaried. The influencing factors or the mechanism and radiolysis products are reviewed. (authors)

  18. Continuous plutonium(IV) oxalate precipitation, filtration, and calcination process. [From product streams from Redox, Purex, or Recuplex solvent extraction plants

    Energy Technology Data Exchange (ETDEWEB)

    Beede, R L

    1956-09-27

    A continuous plutonium (IV) oxalate precipitation, filtration, and calcination process has been developed. Continuous and batch decomposition of the oxalate in the filtrates has been demonstrated. The processes have been demonstrated in prototype equipment. Plutonium (IV) oxalate was precipitated continuously at room temperature by the concurrent addition of plutonium (IV) nitrate feed and oxalic acid into the pan of a modified rotary drum filter. The plutonium (IV) oxalate was calcined to plutonium dioxide, which could be readily hydrofluorinated. Continuous decomposition of the oxalate in synthetic plutonium (IV) oxalate filtrates containing plutonium (IV) oxalate solids was demonstrated using co-current flow in a U-shaped reactor. Feeds containing from 10 to 100 g/1 Pu, as plutonium (IV) nitrate, and 1.0 to 6.5 M HNO/sub 3/, respectively, can be processed. One molar oxalic acid is used as the precipitant. Temperatures of 20 to 35/sup 0/C for the precipitation and filtration are satisfactory. Plutonium (IV) oxalate can be calcined at 300 to 400/sup 0/C in a screw-type drier-calciner to plutonium dioxide and hydrofluorinated at 450 to 550/sup 0/C. Plutonium dioxide exceeding purity requirements has been produced in the prototype equipment. Advantages of continuous precipitation and filtration are: uniform plutonium (IV) oxalate, improved filtration characteristics, elimination of heating and cooling facilities, and higher capacities through a single unit. Advantages of the screw-type drier-calciner are the continuous production of an oxide satisfactory for feed for the proposed plant vibrating tube hydrofluorinator, and ease of coupling continuous precipitation and filtration to this proposed hydrofluorinator. Continuous decomposition of oxalate in filtrates offers advantages in decreasing filtrate storage requirements when coupled to a filtrate concentrator. (JGB)

  19. Radical Cations and Acid Protection during Radiolysis

    Energy Technology Data Exchange (ETDEWEB)

    Mincher, Bruce J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zarzana, Christopher A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mezyk, Stephen P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-09

    Ligand molecules for used nuclear fuel separation schemes are exposed to high radiation fields and high concentrations of acid. Thus, an understanding of the complex interactions between extraction ligands, diluent, and acid is critical to understanding the performance of a separation process. The diglycolamides are ligands with important structural similarities to CMPO; however, previous work has shown that their radiolytic degradation has important mechanistic differences from CMPO. The DGAs do not enjoy radioprotection by HNO3 and the kinetics of DGA radiolytic degradation are different. CMPO degrades with pseudo-zero-order kinetics in linear fashion with absorbed dose while the DGAs degrade in pseudo-first-order, exponential fashion. This suggests that the DGAs degrade by simple reaction with some product of direct diluent radiolysis, while CMPO degradation is probably multi-step, with a slow step that is not dependent on the CMPO concentration, and mitigated by HNO3. It is thus believed that radio-protection and the zero-order radiolytic degradation kinetics are related, and that these phenomena are a function of either the formation of strong acid complexes with CMPO and/or to the presence of the CMPO phenyl ring. Experiments to test both these hypotheses have been designed and partially conducted. This report summarizes findings related to these phenomena for FY16, in satisfaction of milestone M3FT-16IN030104053. It also reports continued kinetic measurements for the reactions of the dodecane radical cation with solvent extraction ligands.

  20. Radical Cations and Acid Protection during Radiolysis

    International Nuclear Information System (INIS)

    Mincher, Bruce J.; Zarzana, Christopher A.; Mezyk, Stephen P.

    2016-01-01

    Ligand molecules for used nuclear fuel separation schemes are exposed to high radiation fields and high concentrations of acid. Thus, an understanding of the complex interactions between extraction ligands, diluent, and acid is critical to understanding the performance of a separation process. The diglycolamides are ligands with important structural similarities to CMPO; however, previous work has shown that their radiolytic degradation has important mechanistic differences from CMPO. The DGAs do not enjoy radioprotection by HNO3 and the kinetics of DGA radiolytic degradation are different. CMPO degrades with pseudo-zero-order kinetics in linear fashion with absorbed dose while the DGAs degrade in pseudo-first-order, exponential fashion. This suggests that the DGAs degrade by simple reaction with some product of direct diluent radiolysis, while CMPO degradation is probably multi-step, with a slow step that is not dependent on the CMPO concentration, and mitigated by HNO 3 . It is thus believed that radio-protection and the zero-order radiolytic degradation kinetics are related, and that these phenomena are a function of either the formation of strong acid complexes with CMPO and/or to the presence of the CMPO phenyl ring. Experiments to test both these hypotheses have been designed and partially conducted. This report summarizes findings related to these phenomena for FY16, in satisfaction of milestone M3FT-16IN030104053. It also reports continued kinetic measurements for the reactions of the dodecane radical cation with solvent extraction ligands.

  1. Plutonium in domestic animals and man

    International Nuclear Information System (INIS)

    Coughtrey, P.J.; Jackson, D.; Jones, C.H.; Kane, P.; Thorne, M.C.

    1984-01-01

    This chapter deals with plutonium adsorption, retention and translocation rates in lungs, the gastrointestinal tract, liver and in body tissues of domestic animals and man. Urinary and faecal excretion of plutonium is discussed. Transfer rates to eggs, milk, foetus and newborn are considered. Of all these subjects, data are presented extracted from literature and cast in tables

  2. Learning more about plutonium

    International Nuclear Information System (INIS)

    2005-01-01

    This document offers chemical, metallurgical and economical information on the plutonium, a hard white radioelement. It deals also on the plutonium formation in the earth, the plutonium use in the nuclear industry, the plutonium in the environment and the plutonium toxicity. (A.L.B.)

  3. Plutonium in nature

    International Nuclear Information System (INIS)

    Madic, C.

    1994-01-01

    Plutonium in nature comes from natural sources and anthropogenic ones. Plutonium at the earth surface comes principally from anthropogenic sources. It is easily detectable in environment. The plutonium behaviour in environment is complex. It seems necessary for the future to reduce releases in environment, to improve predictive models of plutonium behaviour in geosphere, to precise biological impact of anthropogenic plutonium releases

  4. Direct extraction of uranium and plutonium from oxide fuel using TBP-HNO3 complex for super-DIREX process

    International Nuclear Information System (INIS)

    Miura, S.; Kamiya, M.; Nomura, K.; Koyama, T.; Ogum, S.; Shimada, T.; Mori, Y.; Enokida, Y.

    2004-01-01

    Super-DIREX is a new reprocessing method which has high economical efficiency. Experimental study of this process was started on the direct extraction of U and Pu from irradiated MOX fuel by the supercritical carbon dioxide (SFCO 2 ) containing TBP-HNO 3 complex. This report describes direct extraction of U and Pu with TBP-HNO 3 complex at atmospheric pressure, as the first test for irradiated fuel, in order to investigate the applicability of SFCO 2 containing TBP-HNO 3 complex. In this test, dependency on dissolution temperature, Pu content, fuel/ TBP-HNO 3 complex ratio and effect of voloxidation were investigated. From these results, TBP-HNO 3 complex was found to be effective in the respect of the recovery of U and Pu. The number of the process step in dissolution and co-extraction is small, and amount of waste can be reduced. It is applicable to the direct extraction in Super-DIREX. (authors)

  5. Plutonium uniqueness

    International Nuclear Information System (INIS)

    Silver, G.L.

    1984-01-01

    A standard is suggested against which the putative uniqueness of plutonium may be tested. It is common folklore that plutonium is unique among the chemical elements because its four common oxidation states can coexist in the same solution. Whether this putative uniqueness appears only during transit to equilibrium, or only at equilibrium, or all of the time, is not generally made clear. But while the folklore may contain some truth, it cannot be put to test until some measure of 'uniqueness' is agreed upon so that quantitative comparisons are possible. One way of measuring uniqueness is as the magnitude of the product of the mole fractions of the element at equilibrium. A 'coexistence index' is defined and discussed. (author)

  6. Plutonium story

    International Nuclear Information System (INIS)

    Seaborg, G.T.

    1981-09-01

    The first nuclear synthesis and identification (i.e., the discovery) of the synthetic transuranium element plutonium (isotope 238 Pu) and the demonstration of its fissionability with slow neutrons (isotope 239 Pu) took place at the University of California, Berkeley, through the use of the 60-inch and 37-inch cyclotrons, in late 1940 and early 1941. This led to the development of industrial scale methods in secret work centered at the University of Chicago's Metallurgical Laboratory and the application of these methods to industrial scale production, at manufacturing plants in Tennessee and Washington, during the World War II years 1942 to 1945. The chemical properties of plutonium, needed to devise the procedures for its industrial scale production, were studied by tracer and ultramicrochemical methods during this period on an extraordinarily urgent basis. This work, and subsequent investigations on a worldwide basis, have made the properties of plutonium very well known. Its well studied electronic structure and chemical properties give it a very interesting position in the actinide series of inner transition elements

  7. Radiolysis effects on polyethylene terephtalate

    International Nuclear Information System (INIS)

    Zaharescu, Traian; Ciuprina, Florin

    2005-01-01

    The effects of high energy exposure of polyethylene terephtalate, the main electrical insulator for the conduction bars in alternative current generators, is presented. For comparison γ-irradiation was performed in distilled water and air at various doses, up to about 200 kGy. The dependencies of current on time for radiation processed PET sheets allow to depict the variation in the resistivity values as a measure of chemical changes in polyethylene terephtalate macromolecules. The comparison between the evolution of currents in irradiated specimens and spectral analysis bring about a light on the accumulation of radiolysis product in PET matrix. The high energy exposure of PET in air causes an increase of final value of current, while similar experiments in water produces a contrary effect. Some considerations of degradation mechanism are presented

  8. Method of stripping plutonium from tributyl phosphate solution which contains dibutyl phosphate-plutonium stable complexes

    International Nuclear Information System (INIS)

    Ochsenfeld, W.; Schmieder, H.

    1976-01-01

    Fast breeder fuel elements which have been highly burnt-up are reprocessed by extracting uranium and plutonium into an organic solution containing tributyl phosphate. The tributyl phosphate degenerates at least partially into dibutyl phosphate and monobutyl phosphate, which form stable complexes with tetravalent plutonium in the organic solution. This tetravalent plutonium is released from its complexed state and stripped into aqueous phase by contacting the organic solution with an aqueous phase containing tetravalent uranium. 6 claims, 1 drawing figure

  9. Uranium, Plutonium and Neptunium Co-recovery with Irradiated Fast Reactor MOX Fuel by Single Cycle Extraction Process

    Energy Technology Data Exchange (ETDEWEB)

    Masaumi Nakahara; Yuichi Sano; Kazunori Nomura; Tadahiro Washiya; Jun Komaki [Japan Atomic Energy Agency, 4-33 Muramatsu, Tokai-mura, Naka-gun, Ibaraki, 319-1194 (Japan)

    2008-07-01

    The behavior of Np in single cycle extraction processes using tri-n-butylphosphate (TBP) as an extractant for U, Pu and Np co-recovery was investigated as a part of NEXT (New Extraction System for Transuranium) process. Two approaches for Np co-recovery with U and Pu were carried out with irradiated MOX fuel from fast reactor 'JOYO'; one was the counter current experiment using a feed solution with a high HNO{sub 3} concentration and the other used a scrubbing solution with a high HNO{sub 3} concentration. Experimental results showed that the leakage of Np to the raffinate were 0.986 % and 5.96 % under the condition of high HNO{sub 3} concentration in the feed solution and scrubbing solution, respectively. The simulation results based on these experiments indicated that most of Np could be extracted and co-recovered with U and Pu, just by increasing HNO{sub 3} concentrations in the feed and scrubbing solution on the single cycle extraction process. (authors)

  10. Pulse radiolysis studies of model membranes

    International Nuclear Information System (INIS)

    Heijman, M.G.J.

    1984-01-01

    In this thesis the influence of the structure of membranes on the processes in cell membranes were examined. Different models of the membranes were evaluated. Pulse radiolysis was used as the technique to examine the membranes. (R.B.)

  11. Pulse radiolysis facilities and activities in Japan

    International Nuclear Information System (INIS)

    Ogasawara, M.

    1995-01-01

    Pulse radiolysis studies in Japan have been reviewed in special reference to the facilities and the people who have engaged in the experiments. Main achievement is summarized with the list of selected publications. (author)

  12. Solvent extraction of uranium(VI), plutonium(VI) and americium(III) with HTTA/HPMBP using mono- and bi-functional neutral donors. Synergism and thermodynamics

    International Nuclear Information System (INIS)

    Pai, S.A.; Lohithakshan, K.V.; Mithapara, P.D.; Aggarwal, S.K.

    2000-01-01

    Synergistic extraction of hexavalent uranium and plutonium as well as trivalent americium was studied in HNO 3 with thenoyl, trifluoro-acetone (HTTA)/1-phenyl, 3-methyl, 4-benzoyl pyrazolone-5 (HPMBP) in combination with neutral donors viz. DPSO, TBP, TOPO (mono-functional) and DBDECMP, DHDECMP, CMPO (bi-functional) with wide basicity range using benzene as diluent. A linear correlation was observed when the equilibrium constant log Ks for the organic phase synergistic reaction of both U(VI) and Pu(VI) with either of the chelating agents HTTA or HPMBP was plotted vs. the basicity (log Kh) of the donor (both mono- and bi-functional) indicating bi-functional donors also behave as mono-functional. This was supported by the thermodynamic data (ΔG 0 , ΔH 0 , ΔS 0 ) obtained for these systems. The organic phase adduct formation reactions were identified for the above systems from the thermodynamic data. In the Am(III) HTTA system log K s values of bi-functional donors were found to be very high and deviate from the linear plot (log K s vs. log K h ) obtained for mono-functional donors, indicating that they function as bi-functional for the Am(III)/HTTA) system studied. This was supported by high +ve ΔS 0 values obtained for this system. (author)

  13. Radiolysis of anthraquinone dyes in aqueous solutions

    International Nuclear Information System (INIS)

    Vysotskaya, N.A.; Bortun, L.N.; Ogurtsov, N.A.; Migdalovich, E.A.; Revina, A.A.; Volodko, V.V.; AN SSSR, Moscow. Inst. Ehlektrokhimii)

    1986-01-01

    The commercial anthraquinone dyes (Dark Blue, Light Blue, Green) in aqueous solutions were shown to be decoloured and degrade under the action of ionizing radiation. The degree of decolouration and degradation of aromatic rings was found to increase in presence of oxygen. Hydroxyl radicals were shown to play the key role in the degradation of the dyes under irradiation. The radiolysis intermediate products were studied using the pulse radiolysis technique. (author)

  14. Decontaminaion of metals containing plutonium and americium

    International Nuclear Information System (INIS)

    Seitz, M.G.; Gerding, T.J.; Steindler, M.J.

    1979-06-01

    Melt-slagging (melt-refining) techniques were evaluated as a decontamination and consolidation step for metals contaminated with oxides of plutonium and americium. Experiments were performed in which mild steel, stainless steel, and nickel contaminated with oxides of plutonium and americium were melted in the presence of silicate slags of various compositions. The metal products were low in contamination, with the plutonium and americium strongly fractionated to the slags. Partition coefficients (plutonium in slag/plutonium in steel) of 7 x 10 6 were measured with boro-silicate slag and of 3 x 10 6 with calcium, magnesium silicate slag. Decontamination of metals containing as much as 14,000 ppM plutonium appears to be as efficient as for metals with plutonium levels of 400 ppM. Staged extraction, that is, a remelting of processed metal with clean slag, results in further decontamination of the metal. The second extraction is effective with either resistance-furnace melting or electric-arc melting. Slag adhering to the metal ingots and in defects within the ingots is in the important contributors to plutonium retained in processed metals. If these sources of plutonium are controlled, the melt-refining process can be used on a large scale to convert highly contaminated metals to homogeneous and compact forms with very low concentrations of plutonium and americium. A conceptual design of a melt-refining process to decontaminate plutonium- and americium-contaminated metals is described. The process includes single-stage refining of contaminated metals to produce a metal product which would have less than 10 nCi/g of TRU-element contamination. Two plant sizes were considered. The smaller conceptual plant processes 77 kg of metal per 8-h period and may be portable.The larger one processes 140 kg of metal per 8-h period, is stationary, and may be near te maximum size that is practical for a metal decontamination process

  15. gamma-radiolysis and pulse radiolysis of aqueous 4-chloroanisole

    DEFF Research Database (Denmark)

    Quint, R.M.; Park, H.R.; Krajnik, P.

    1996-01-01

    of oxygen leads to its addition on the hydroxpcyclohexadienyl radicals, k(OH-adduct + O-2) = 3.2 x 10(8) dm(3) mol(-1) s(-1). In airfree solution the reaction of H-atom with the substrate, k(H + 4-ClAn) = 1.2 x 10(9) dm(3) mol(-1) s(-1), results in H-adducts which decay in bimolecular reactions, 2k = 8.2 x...... 10(8) dm(2) mol(-1) s(-1). The rate constant for the reaction of the solvated electrons has been determined to k (e(aq)(-) + 4-CIAn) = 2 x 10(9) dm(2) mol(-1) s(-1). The absorption spectra of H- and OH-adducts were measured in the range of 280-450 nm. The products analysed by HPLC after T......-radiolysis in dependence of dose (100-600 Gy) are given for N2O-, air-, oxygen- and argon saturated neutral aqueous solutions. In conditions favoring the OH radical oxidation 4-chlorophenol, 4-methoxyphenol, 5-chloro-2-methoxyphenol and 2-chloro-5-methoxyphenol were determined as final products. In the presence of Ar...

  16. A pulse radiolysis study of hyperoside isolated from Hypericum mysorense

    International Nuclear Information System (INIS)

    Hariharapura, Raghu C.; Mahal, H.S.; Srinivasan, R.; Jagani, Hitesh; Vijayan, P.

    2015-01-01

    Background: The recent growth in knowledge of free radicals in biology is producing a medical revolution that promises a new age in health and disease management. In the last two decades there has been an explosive interest in the role of oxygen free radicals, more generally known as “reactive oxygen species” and of “reactive nitrogen species” in experimental and clinical medicine. Methods: The flowering top extract of Hypericum mysorense possessing potent anti-oxidant activity was subjected to bio-active guided isolation. Pulse radiolysis technique was used to determine the transient spectrum and rate constant for the one-electron oxidation of hyperoside by · OH, N 3 · , NO 2 · , NO · , CCl 3 OO · radicals in aqueous solution. Results: Three compounds were isolated and characterized as rutin, quercetin-3-O-galactoside (hyperoside) and quercetin from spectral analysis. The hyperoside radical showed pK a1 and pK a2 at 5.4 and 9.2. Both, Cu(II) and iron(II) ions form chelate with hyperoside. The Cu–hyperoside chelate was able to scavenge O 2 ·− , k=7.0(±0.3)×10 6 dm 3 mol −1 s −1 at pH 9. The repair rates for tryptophan and guanosine radicals by hyperoside were also determined. Conclusion: The reduction potential of hyperoside radical was determined by cyclic voltammetric and pulse radiolysis methods. - Highlights: • Hyperoside, rutin and quercetin were isolated from extract of Hypericum mysorense. • Rate constant of hyperoside was determined by Pulse radiolysis technique. • The hyperoside radical showed pK a1 and pK a2 at 5.4 and 9.2. • Cu(II) and iron(II)ions form chelate with hyperoside. • Hyperoside can repair the damage to guanosine, tryptophan radicals

  17. PRODUCTION OF PLUTONIUM METAL

    Science.gov (United States)

    Lyon, W.L.; Moore, R.H.

    1961-01-17

    A process is given for producing plutonium metal by the reduction of plutonium chloride, dissolved in alkali metal chloride plus or minus aluminum chloride, with magnesium or a magnesium-aluminum alloy at between 700 and 800 deg C and separating the plutonium or plutonium-aluminum alloy formed from the salt.

  18. SEPARATION OF PLUTONIUM

    Science.gov (United States)

    Maddock, A.G.; Smith, F.

    1959-08-25

    A method is described for separating plutonium from uranium and fission products by treating a nitrate solution of fission products, uranium, and hexavalent plutonium with a relatively water-insoluble fluoride to adsorb fission products on the fluoride, treating the residual solution with a reducing agent for plutonium to reduce its valence to four and less, treating the reduced plutonium solution with a relatively insoluble fluoride to adsorb the plutonium on the fluoride, removing the solution, and subsequently treating the fluoride with its adsorbed plutonium with a concentrated aqueous solution of at least one of a group consisting of aluminum nitrate, ferric nitrate, and manganous nitrate to remove the plutonium from the fluoride.

  19. Picosecond radiolysis of ionic liquids

    International Nuclear Information System (INIS)

    Funston, A.M.; Wishart, J.F.; Neta, P.; Lall, S.I.; Engel, R.

    2003-01-01

    Ionic liquids (ILs) are a rapidly expanding family of condensed-phase media with important applications in nuclear fuel and waste processing, energy production, improving the efficiency and safety of industrial chemical processes, and pollution prevention. Ionic liquids are completely nonvolatile, noncombustible, highly conductive, recyclable and capable of dissolving a wide variety of materials. An understanding of the radiation chemistry of ionic liquids is important for development of their applications in radioactive material processing and for the application of pulse radiolysis techniques to the general study of chemical reactivity in ionic liquids. Kinetic studies with a picosecond electron accelerator, such as the BNL Laser-Electron Accelerator Facility (LEAF), allow one to observe primary radiation products and their reactions on short time scales. For example, the solvated electron lifetime in neat methyltributylammonium bis(trifluoromethylsulfonyl)imide is ∼300 ns and its absorption maximum is ∼1400 nm. Kinetic studies of primary radiolytic products and their reactivities will be described for several types of ionic liquids. Supported in part by the U.S. Department of Energy, Division of Chemical Sciences, Office of Basic Energy Sciences, under contract DE-AC02-98-CH1088

  20. Radiolysis of Aqueous Toluene Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, H C; Gustafson, R

    1971-04-15

    Aqueous toluene solutions have been irradiated with Co gamma-rays. In unbuffered solutions the various cresol isomers are formed in a total yield of 0.45, 0.87 and 0.94 molecules/100 eV absorbed energy in argon-, N{sub 2}O- and air - saturated solutions, respectively. The yields are reduced in acid (pH 3) solutions (G = 0.14, 0.14 and 0.52, respectively) but the reduction is compensated by the formation of 1,2-di-phenylethane in yields of 0.49 and 1.60 in argon- and N{sub 2}O-saturated solutions, respectively. Benzyl radicals are formed through an acid catalysed water elimination reaction from the initially formed hydroxymethylcyclohexadienyl radical. Phenyltolylmethanes, dimethylbiphenyls and partly reduced dimers are also formed during the radiolysis. Hydrogen is formed in the same yield as the molecular yield, g(H{sub 2}). Xylene isomers and benzene are formed in trace quantities. The most remarkable effects of the addition of Fe(III) ions to deaerated acid toluene solutions are the formation of benzyl alcohol and benzaldehyde and an increase in the yield of 1,2-diphenylethane

  1. Radiolysis of Aqueous Toluene Solutions

    International Nuclear Information System (INIS)

    Christensen, H.C.; Gustafson, R.

    1971-04-01

    Aqueous toluene solutions have been irradiated with Co γ-rays. In unbuffered solutions the various cresol isomers are formed in a total yield of 0.45, 0.87 and 0.94 molecules/100 eV absorbed energy in argon-, N 2 O- and air - saturated solutions, respectively. The yields are reduced in acid (pH 3) solutions (G 0.14, 0.14 and 0.52, respectively) but the reduction is compensated by the formation of 1,2-di-phenylethane in yields of 0.49 and 1.60 in argon- and N 2 O-saturated solutions, respectively. Benzyl radicals are formed through an acid catalysed water elimination reaction from the initially formed hydroxymethylcyclohexadienyl radical. Phenyltolylmethanes, dimethylbiphenyls and partly reduced dimers are also formed during the radiolysis. Hydrogen is formed in the same yield as the molecular yield, g(H 2 ). Xylene isomers and benzene are formed in trace quantities. The most remarkable effects of the addition of Fe(III) ions to deaerated acid toluene solutions are the formation of benzyl alcohol and benzaldehyde and an increase in the yield of 1,2-diphenylethane

  2. Some mechanisms which may reduce radiolysis

    Energy Technology Data Exchange (ETDEWEB)

    Neretnieks, I; Faghihi, M. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering

    1991-08-01

    In this report two mechanisms which may considerably decrease the rate of radiolysis are studied. The first main effect is that capillary forces in the very fine pores of the bentonite which surround the canisters do not permit the release of water if there is a gas over pressure inside the canister. As long as there is gas inside the canister the gap will partly be gas filled and the alpha-particles will have less water to radiolyze. Because some hydrogen will be dissolved and will escape by diffusion, a rate of radiolysis will be maintained which balances the rate of diffusion. This in turn will be influenced by the geometry of the diffusion path. The size of the hole in the copper canister seems to be one of the critical items which determine the escape of the hydrogen and thus the rate of radiolysis. The other main effect which will reduce the radiolysis is the accumulation of the corrosion products in the gap. This reduces the water content in the gap. Consequently there will be less water which can be radiolyzed. The presence of corrosion products which have a higher density than water will also consume the energy of the alpha-particles faster. Both effects seem to, independently, have a potential of reducing the rate of radiolysis by a few order of magnitude.

  3. Some mechanisms which may reduce radiolysis

    International Nuclear Information System (INIS)

    Neretnieks, I; Faghihi, M.

    1991-08-01

    In this report two mechanisms which may considerably decrease the rate of radiolysis are studied. The first main effect is that capillary forces in the very fine pores of the bentonite which surround the canisters do not permit the release of water if there is a gas over pressure inside the canister. As long as there is gas inside the canister the gap will partly be gas filled and the alpha-particles will have less water to radiolyze. Because some hydrogen will be dissolved and will escape by diffusion, a rate of radiolysis will be maintained which balances the rate of diffusion. This in turn will be influenced by the geometry of the diffusion path. The size of the hole in the copper canister seems to be one of the critical items which determine the escape of the hydrogen and thus the rate of radiolysis. The other main effect which will reduce the radiolysis is the accumulation of the corrosion products in the gap. This reduces the water content in the gap. Consequently there will be less water which can be radiolyzed. The presence of corrosion products which have a higher density than water will also consume the energy of the alpha-particles faster. Both effects seem to, independently, have a potential of reducing the rate of radiolysis by a few order of magnitude

  4. Gamma radiolysis of the highly selective ligands CyMe{sub 4}BTBP and CyMe{sub 4}BTPhen: Qualitative and quantitative investigation of radiolysis product

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, H.; Wilden, A.; Modolo, G.; Bosbach, D. [Forschungszentrum Juelich GmbH, Institute of Energy and Climate Research IEK-6: Nuclear Waste Management, 52425 Juelich (Germany); Santiago-Schuebel, B.; Hupert, M. [Forschungszentrum Juelich GmbH, Central Institute for Engineering, Analytics - ZEA-3, 52425 Juelich (Germany); Svehla, J.; Gruner, B. [Institute of Inorganic Chemistry, Academy of Sciences, Hlavni 1001, 25068 Husinec-Rez (Czech Republic); Ekberg, C. [Department of Chemical and Biochemical Engineering, Chalmers University of Technology, 41296 Gothenburg (Sweden)

    2016-07-01

    The highly selective nitrogen donor ligands CyMe{sub 4}BTBP and CyMe4{sub B}TPhen where γ-irradiated under identical experimental conditions in 1-octanol with and without contact to nitric acid solution. Subsequently, solvent extraction experiments were carried out to evaluate the stability of the extractants against γ-radiation monitoring Am(III) and Eu(III) distribution ratios. Generally, decreasing distribution ratios with increasing absorbed dose were detected for both molecules. Furthermore, qualitative mass spectrometric analyses were performed and ligand concentrations were determined by HPLC-DAD after irradiation to investigate the radiolysis mechanism. An exponential decrease with increasing absorbed dose was observed for both ligands with a faster rate for CyMe{sub 4}BTPhen. Main radiolysis products indicated the addition of one or more diluent molecules (1-octanol) to the ligand via prior production of α-hydroxy-octyl radicals from diluent radiolysis. The addition of nitric acid during the irradiation lead to a remarkable stabilization of the system, as the extraction of Am(III) and Eu(III) did not change significantly over the whole examined dose range. Quantification of the remaining ligand concentration on the other hand showed decreasing concentrations with increasing absorbed dose. The stabilization of D values is therefore explained by the formation of 1-octanol addition products which are also able to extract the studied metal ions. (authors)

  5. Gamma radiolysis of the highly selective ligands CyMe_4BTBP and CyMe_4BTPhen: Qualitative and quantitative investigation of radiolysis product

    International Nuclear Information System (INIS)

    Schmidt, H.; Wilden, A.; Modolo, G.; Bosbach, D.; Santiago-Schuebel, B.; Hupert, M.; Svehla, J.; Gruner, B.; Ekberg, C.

    2016-01-01

    The highly selective nitrogen donor ligands CyMe_4BTBP and CyMe4_BTPhen where γ-irradiated under identical experimental conditions in 1-octanol with and without contact to nitric acid solution. Subsequently, solvent extraction experiments were carried out to evaluate the stability of the extractants against γ-radiation monitoring Am(III) and Eu(III) distribution ratios. Generally, decreasing distribution ratios with increasing absorbed dose were detected for both molecules. Furthermore, qualitative mass spectrometric analyses were performed and ligand concentrations were determined by HPLC-DAD after irradiation to investigate the radiolysis mechanism. An exponential decrease with increasing absorbed dose was observed for both ligands with a faster rate for CyMe_4BTPhen. Main radiolysis products indicated the addition of one or more diluent molecules (1-octanol) to the ligand via prior production of α-hydroxy-octyl radicals from diluent radiolysis. The addition of nitric acid during the irradiation lead to a remarkable stabilization of the system, as the extraction of Am(III) and Eu(III) did not change significantly over the whole examined dose range. Quantification of the remaining ligand concentration on the other hand showed decreasing concentrations with increasing absorbed dose. The stabilization of D values is therefore explained by the formation of 1-octanol addition products which are also able to extract the studied metal ions. (authors)

  6. Plutonium-239

    International Nuclear Information System (INIS)

    Ammerich, Marc; Frot, Patricia; Gambini, Denis-Jean; Gauron, Christine; Moureaux, Patrick; Herbelet, Gilbert; Lahaye, Thierry; Pihet, Pascal; Rannou, Alain

    2014-06-01

    This sheet belongs to a collection which relates to the use of radionuclides essentially in unsealed sources. Its goal is to gather on a single document the most relevant information as well as the best prevention practices to be implemented. These sheets are made for the persons in charge of radiation protection: users, radioprotection-skill persons, labor physicians. Each sheet treats of: 1 - the radio-physical and biological properties; 2 - the main uses; 3 - the dosimetric parameters; 4 - the measurement; 5 - the protection means; 6 - the areas delimitation and monitoring; 7 - the personnel classification, training and monitoring; 8 - the effluents and wastes; 9 - the authorization and declaration administrative procedures; 10 - the transport; and 11 - the right conduct to adopt in case of incident or accident. This sheet deals specifically with Plutonium-239

  7. Study of water radiolysis in porous media

    International Nuclear Information System (INIS)

    Rotureau, Patricia

    2001-08-01

    The understanding of the production of H 2 in the radiolysis of water confined into pores of concrete is important for the disposal of radioactive waste. In order to describe the mechanisms of water radiolysis in such heterogeneous porous systems we have studied the behaviour under gamma radiation of water confined in porous silica glasses with pores going from 8 to 300 nm of diameter and meso-porous molecular sieves (MCM-41). The radiolytic yields of hydroxyl radicals, hydrated electron and dihydrogen, have been determined with respect to the pore size of materials. The increase of these radiolytic yields compared to those of free water allowed us to show a charge transfer from silica to confined water. On the other hand the kinetics of hydrated electron reactions measured by pulse radiolysis are not modified. (author) [fr

  8. Radical production in the radiolysis of benzene

    International Nuclear Information System (INIS)

    LaVerne, J.A.; Araos, M.S.

    1998-01-01

    Complete text of publication follows. Benzene is the prototypical aromatic compound and yet the radiation chemistry of the radicals formed in its radiolysis is not well understood. Temporal information on the yield of phenyl radical, the major radical produced in the radiolysis, is important for understanding the radiation chemistry of many other types of aromatic compounds including some polymers. The effects of track structure on the production of phenyl radicals have been examined using iodine-scavenging techniques. The variation of the yields of iodobenzene and the other major molecular products such as biphenyl as a function of iodine concentration gives a good indication of the competition kinetics occurring in particle tracks. Experimental results of the scavenger experiments will be shown and their implications in the radiolysis of condensed hydrocarbons will be discussed

  9. Formation of stable radicals during perfluoroalkane radiolysis

    International Nuclear Information System (INIS)

    Allayarov, S.R.; Demidov, S.V.; Kiryukhin, D.P.; Mikhajlov, A.I.; Barkalov, I.M.

    1984-01-01

    Accumulation and stabilization kinetics of perfluoroalkyls during α-radiolysis ( 60 Co) of perfluoralkanes (PFA) in a wide temperature range for different PFA fractions differing in the average molecular weight, is investigated. It is noted that low temperature (PFA) radiolysis (77 K) is of a linear nature of accumulation of stabilized radicals up to doses of approximately 700 KGy. In the case of PFA radiolysis at 300 K radiation yields of stable radicals are somewhat lower than at 47 K and at doses of 200-300 KGy, their accumulation ceases. It is shown that kinetics of formation and accumulation of stable radicals does not depend on molecular mass and PFA fraction viscosity. Perfluoroalkyl stability is explained by intra molecular conformation spheric insulation of the free valency. Perfluoroalkyl stability in different PFA fractions in a wide time range in different media is investigated

  10. Gamma radiolysis and vinyl esters

    International Nuclear Information System (INIS)

    De Bruyn, H.; Balic, R.; Gilbert, R.G.

    1998-01-01

    The principle behind γ relaxation of free-radical polymerizations is that the source of initiating radicals can be switched off 'instantaneously'. In the absence of initiating radicals the only kinetic events remaining are propagation, transfer and termination. For monomers whose propagation rate coefficients have been determined, relaxation behaviour can be interpreted to determine radical-loss rate coefficients and test models of loss mechanisms. This technique has been employed successfully on styrene and MMA emulsion polymerizations. In the present study, vinyl acetate and vinyl neo-decanoate (a ten-carbon-branched homologue of vinyl acetate) were studied, with the propagation rate coefficients for both monomers being established by pulsed-laser polymerization. Both were found to exhibit rapid γ relaxation rates in emulsion polymerization. This is a surprising result because mechanisms for rapid relaxation in emulsion polymerizations require that chain transfer to monomer (which is rapid for both monomers) is followed by exit from the particle into the aqueous phase with subsequent re-entry into a radical-containing particle leading to bimolecular termination. It is not unreasonable to suppose that this may be possible for vinyl acetate which is fairly water soluble (∼0.3 M). However, vinyl neo-decanoate is virtually insoluble (∼0.00004 M) and hence desorption is extremely unlikely. The most likely explanation for the observed rapid relaxations is that some of the radicals produced by γ radiolysis are slow to initiate vinyl esters and hence act as radical traps. As vinyl esters are known to be particularly unreactive monomers. it is feasible that this experimental artifact affects them to a much greater extent than some of the monomers studied successfully with this technique in the past

  11. Radiolysis of Aqueous Benzene Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, H

    1964-05-15

    Aerated and deaerated aqueous solutions of benzene have been irradiated with {sup 60}Co {gamma}-rays. The products of radiolysis in deaerated, unbuffered or acid, solutions were phenol, biphenyl, hydrogen and in acid solutions also hydrogen peroxide with the following yields: G(phenol) = 0. 37 (0. 37), G(biphenyl) = 1.3 (1.7), G(H{sub 2}) = 0.44 (0. 43) and G(H{sub 2}O{sub 2}) = 0 (0.60), the figures in brackets giving the results for acid solutions. The results are shown to agree with the conclusion that k(e{sup -}{sub aq} + H{sub 2}O{sub 2}) >> k(H + H{sub 2}O{sub 2}). Furthermore, the results indicate that a competition takes place between the reactions: 2 C{sub 6}H{sub 6}OH {center_dot} -> dimer -> biphenyl. C{sub 6}H{sub 7} {center_dot} + C{sub 6}H{sub 6}OH {center_dot} -> dimer -> biphenyl. The yields in aerated, unbuffered or acid, solutions were: G(phenol) = 2.1 (2.3), G(biphenyl) = 0 (0), and G(H{sub 2}O{sub 2}) = 2.2 (3.1), the figures in brackets being valid for acid solutions. The ratio k(H + C{sub 6}H{sub 6})/k(H + O{sub 2}) was 1.4x10{sup -2}. The results indicate that peroxides, or more probably hydroperoxides, take part in the reactions. After the addition of Fe{sup 2+} or Fe{sup 3+} to aerated acid solutions G(phenol) was increased to 6.6 and 3.4 respectively. Oxygen was consumed more rapidly in the presence of Fe. Reaction mechanisms are discussed.

  12. The plutonium fuel cycles

    International Nuclear Information System (INIS)

    Pigford, T.H.; Ang, K.P.

    1975-01-01

    The quantities of plutonium and other fuel actinides have been calculated for equilibrium fuel cycles for 1000-MW water reactors fueled with slightly enriched uranium, water reactors fueled with plutonium and natural uranium, fast-breder reactors, gas-cooled reactors fueled with thorium and highly enriched uranium, and gas-cooled reactors fueled with thorium, plutonium and recycled uranium. The radioactivity quantities of plutonium, americium and curium processed yearly in these fuel cycles are greatest for the water reactors fueled with natural uranium and recycled plutonium. The total amount of actinides processed is calculated for the predicted future growth of the U.S. nuclear power industry. For the same total installed nuclear power capacity, the introduction of the plutonium breeder has little effect upon the total amount of plutonium in this century. The estimated amount of plutonium in the low-level process wastes in the plutonium fuel cycles is comparable to the amount of plutonium in the high-level fission product wastes. The amount of plutonium processed in the nuclear fuel cycles can be considerably reduced by using gas-cooled reactors to consume plutonium produced in uranium-fueled water reactors. These, and other reactors dedicated for plutonium utilization, could be co-located with facilities for fuel reprocessing ad fuel fabrication to eliminate the off-site transport of separated plutonium. (author)

  13. The plutonium challenge for the future

    International Nuclear Information System (INIS)

    Gray, L.W.

    2000-01-01

    , followed by dissolution utilizing an Ag(II)-nitric acid method. The plutonium would be purified by one cycle of solvent extraction, precipitated as plutonium oxalate and then converted to oxide. This would not only remove the gallium but would provide the correct morphology for preparation of the MOX fuel. The Immobilization program in the United States would mineralize the plutonium contained in a variety of residues that were left in place when the weapons production complex was shut-down at the end of the cold war. These residues have a wide range of impurity contents, typically from a few parts per million to > 90 wt. %. Plutonium in these residues would be blended to level the impurities and thereby avoid reprocessing of this plutonium. This blended plutonium would then be mineralized at high temperature in a titanate ceramic followed by canning of the ceramic pucks. These cans would by loaded into a magazine and then locked into place within a stainless steel canister. The plutonium ceramic would then be encased in high level waste glass. A high radiation field would protect the plutonium in the spent MOX fuel and the immobilized ceramic form for some period of time. Within the time period of the high radiation field, these forms would be entombed in an underground repository. This, however, disposes of only 50 tonnes of the approximately 1700 tonnes of the worldwide weapons- usable plutonium. Russia will dispose of another 50 tonnes via the MOX burning route. Worldwide approximately 1600 tonnes of weapons-usable plutonium is still available either as spent fuel or as separate plutonium oxide. Is society prepared to deal with these 1600 tonnes of plutonium? At the present growth rate, before the United States and Russia completes the disposition of the 100 tonnes of weapons-grade plutonium, the worldwide stockpile will exceed 2000 tonnes. (author)

  14. Development of subpicosecond pulse radiolysis system

    CERN Document Server

    Kozawa, T; Miki, M; Yamamoto, T; Suemine, S; Yoshida, Y; Tagawa, S

    2000-01-01

    The highest time resolution of the pulse radiolysis had remained about 30 ps since the late 1960s. To make clear the primary processes in the radiation chemistry and physics within 30 ps, we developed a stroboscopic pulse radiolysis system for the absorption spectroscopy with the time resolution of 2.0 ps (10-90% rise time). The time resolution of 2.0 ps was estimated from the time-dependent behavior of the hydrated electrons. The system consists of a subpicosecond electron linac as an irradiation source, a femtosecond laser as an analyzing light and a jitter compensation system.

  15. Pulse radiolysis study of egg white

    International Nuclear Information System (INIS)

    Micic, O.I.; Josimovic, L.; Markovic, V.

    1978-01-01

    Radiolytic processes in egg white in intervals of 0.1μs to several seconds have been studied by the pulse radiolysis technique. The formation and decay of short-lived intermediates and their absorption spectra were observed under varied experimental conditions. The results show that intermediates are produced predominantly in reactions of radicals formed in water radiolysis with egg white proteins. The intermediates decay mainly in the first-order intermolecular processes, though the mechanism of transformations is very complex. (author)

  16. SEPARATION OF URANIUM, PLUTONIUM, AND FISSION PRODUCTS

    Science.gov (United States)

    Spence, R.; Lister, M.W.

    1958-12-16

    Uranium and plutonium can be separated from neutron-lrradiated uranium by a process consisting of dissolvlng the lrradiated material in nitric acid, saturating the solution with a nitrate salt such as ammonium nitrate, rendering the solution substantially neutral with a base such as ammonia, adding a reducing agent such as hydroxylamine to change plutonium to the trivalent state, treating the solution with a substantially water immiscible organic solvent such as dibutoxy diethylether to selectively extract the uranium, maklng the residual aqueous solutlon acid with nitric acid, adding an oxidizing agent such as ammonlum bromate to oxidize the plutonium to the hexavalent state, and selectlvely extracting the plutonium by means of an immlscible solvent, such as dibutoxy dlethyletber.

  17. The first metallurgical tests on plutonium

    International Nuclear Information System (INIS)

    Grison, E.; Abramson, R.; Anselin, F.; Monti, H.

    1958-01-01

    Metallic plutonium was first prepared in France in January 1956, as soon as we had access to quantities of the order of several grams of plutonium, which had been extracted from the rods of the pile EL2 at Saclay. Since up to the present this reactor, of thermal power 2 000 kW, has been our only source of plutonium, we have so far only worked on experimental quantities sufficient for the basic tests but not for tests on a scale of possible applications. It is this work, carried out during this phase of preliminary research, which is described below. With the starting up of the plutonium extraction plant at Marcoule, where the reactor G1 has been operating at power for more than a year, we shall go on next to a another order of magnitude which will allow the manufacture and experimentation of prototype fuel elements. (author) [fr

  18. Plutonium economy

    International Nuclear Information System (INIS)

    Traube, K.

    1984-01-01

    The author expresses his opinion on the situation, describes the energy-economic setting, indicates the alternatives: fuel reprocessing or immediate long-term storage, and investigates the prospects for economic utilization of the breeder reactors. All the facts suggest that the breeder reactor will never be able to stand economic competition with light-water reactors. However, there is no way to prove the future. It is naive to think that every doubt could and must be removed before stopping the development of breeder reactors - and thus also the reprocessing of the fuel of light-water reactors. On the basis of the current state of knowledge an unbiased cost-benefit-analysis can only lead to the recommendation to stop construction immediately. But can 'experts', who for years or even decades have called for and supported the development of breeder reactors be expected to make an unbiased analysis. Klaus Traube strikes the balance of the state Germany's nuclear economy is in: although there is no chance of definitively abandoning that energy-political cul-de-sac, no new adventures must be embarked upon. Responsible handling of currently used nuclear technology means to give up breeder technology and waive plutonium economy. It is no supreme technology with the aid of which structural unemployment or any other economic problem could be solved. (orig.) [de

  19. Reclamation of plutonium from pyrochemical processing residues

    International Nuclear Information System (INIS)

    Gray, L.W.; Gray, J.H.; Holcomb, H.P.; Chostner, D.F.

    1987-04-01

    Savannah River Laboratory (SRL), Savannah River Plant (SRP), and Rocky Flats Plant (RFP) have jointly developed a process to recover plutonium from molten salt extraction residues. These NaCl, KCL, and MgCl 2 residues, which are generated in the pyrochemical extraction of 241 Am from aged plutonium metal, contain up to 25 wt % dissolved plutonium and up to 2 wt % americium. The overall objective was to develop a process to convert these residues to a pure plutonium metal product and discardable waste. To meet this objective a combination of pyrochemical and aqueous unit operations was used. The first step was to scrub the salt residue with a molten metal (aluminum and magnesium) to form a heterogeneous ''scrub alloy'' containing nominally 25 wt % plutonium. This unit operation, performed at RFP, effectively separated the actinides from the bulk of the chloride salts. After packaging in aluminum cans, the ''scrub alloy'' was then dissolved in a nitric acid - hydrofluoric acid - mercuric nitrate solution at SRP. Residual chloride was separated from the dissolver solution by precipitation with Hg 2 (NO 3 ) 2 followed by centrifuging. Plutonium was then separated from the aluminum, americium and magnesium using the Purex solvent extraction system. The 241 Am was diverted to the waste tank farm, but could be recovered if desired

  20. Transfer of Plutonium-Uranium Extraction Plant and N Reactor irradiated fuel for storage at the 105-KE and 105-KW fuel storage basins, Hanford Site, Richland Washington

    International Nuclear Information System (INIS)

    1995-07-01

    The U.S. Department of Energy (DOE) needs to remove irradiated fuel from the Plutonium-Uranium Extraction (PUREX) Plant and N Reactor at the Hanford Site, Richland, Washington, to stabilize the facilities in preparation for decontamination and decommissioning (D ampersand D) and to reduce the cost of maintaining the facilities prior to D ampersand D. DOE is proposing to transfer approximately 3.9 metric tons (4.3 short tons) of unprocessed irradiated fuel, by rail, from the PUREX Plant in the 200 East Area and the 105 N Reactor (N Reactor) fuel storage basin in the 100 N Area, to the 105-KE and 105-KW fuel storage basins (K Basins) in the 100 K Area. The fuel would be placed in storage at the K Basins, along with fuel presently stored, and would be dispositioned in the same manner as the other existing irradiated fuel inventory stored in the K Basins. The fuel transfer to the K Basins would consolidate storage of fuels irradiated at N Reactor and the Single Pass Reactors. Approximately 2.9 metric tons (3.2 short tons) of single-pass production reactor, aluminum clad (AC) irradiated fuel in four fuel baskets have been placed into four overpack buckets and stored in the PUREX Plant canyon storage basin to await shipment. In addition, about 0.5 metric tons (0.6 short tons) of zircaloy clad (ZC) and a few AC irradiated fuel elements have been recovered from the PUREX dissolver cell floors, placed in wet fuel canisters, and stored on the canyon deck. A small quantity of ZC fuel, in the form of fuel fragments and chips, is suspected to be in the sludge at the bottom of N Reactor's fuel storage basin. As part of the required stabilization activities at N Reactor, this sludge would be removed from the basin and any identifiable pieces of fuel elements would be recovered, placed in open canisters, and stored in lead lined casks in the storage basin to await shipment. A maximum of 0.5 metric tons (0.6 short tons) of fuel pieces is expected to be recovered

  1. Plutonium Finishing Plant

    Data.gov (United States)

    Federal Laboratory Consortium — The Plutonium Finishing Plant, also known as PFP, represented the end of the line (the final procedure) associated with plutonium production at Hanford.PFP was also...

  2. Plutonium biokinetics in humans

    International Nuclear Information System (INIS)

    Popplewell, D.; Ham, G.; McCarthy, W.; Lands, C.

    1994-01-01

    By using an 'unusual' isotope it is possible to carry out experiments with plutonium in volunteers at minimal radiation dose levels. Measurements have been made of the gut transfer factor and the urinary excretion of plutonium after intravenous injection. (author)

  3. Plutonium in uranium deposits

    International Nuclear Information System (INIS)

    Curtis, D.; Fabryka-Martin, J.; Aguilar, R.; Attrep, M. Jr.; Roensch, F.

    1992-01-01

    Plutonium-239 (t 1/2 , 24,100 yr) is one of the most persistent radioactive constituents of high-level wastes from nuclear fission power reactors. Effective containment of such a long-lived constituent will rely heavily upon its containment by the geologic environment of a repository. Uranium ore deposits offer a means to evaluate the geochemical properties of plutonium under natural conditions. In this paper, analyses of natural plutonium in several ores are compared to calculated plutonium production rates in order to evaluate the degree of retention of plutonium by the ore. The authors find that current methods for estimating production rates are neither sufficiently accurate nor precise to provide unambiguous measures of plutonium retention. However, alternative methods for evaluating plutonium mobility are being investigated, including its measurement in natural ground waters. Preliminary results are reported and establish the foundation for a comprehensive characterization of plutonium geochemistry in other natural environments

  4. Plutonium metal burning facility

    International Nuclear Information System (INIS)

    Hausburg, D.E.; Leebl, R.G.

    1977-01-01

    A glove-box facility was designed to convert plutonium skull metal or unburned oxide to an oxide acceptable for plutonium recovery and purification. A discussion of the operation, safety aspects, and electrical schematics are included

  5. Plutonium Training Opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Balatsky, Galya Ivanovna [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wolkov, Benjamin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-26

    This report was created to examine the current state of plutonium training in the United States and to discover ways in which to ensure that the next generation of plutonium workers are fully qualified.

  6. Application of chemsimul for groundwater radiolysis

    DEFF Research Database (Denmark)

    Christensen, Hilbert; Bjergbakke, Erling

    1986-01-01

    The application of the radiation chemical computer program chemsimul, for the calculation of radiolysis in connection with the storage of high level waste has been studied. Methods have been developed for the diffusion of gases out of the irradiated system, for the continuous addition of Fe2...

  7. Pulse radiolysis of anthraquinone dye aqueous solution

    International Nuclear Information System (INIS)

    Perkowski, J.; Gebicki, J.L.; Lubis, R.; Mayer, J.

    1988-01-01

    Pulse radiolysis of argon flushed aqueous solutions of 10 -5 -10 -4 mol dm -3 anthraquinone dye (C.I. Acid Blue 62) gives rise to the transients originated from the reactions of e - aq , OH and H. The rate constants of these reactions are determined. (author)

  8. Optimization and plutonium equilibrium

    International Nuclear Information System (INIS)

    Silver, G.L.

    1976-01-01

    The sequential simplex method has been used to estimate the extent of disproportionation of tetravalent plutonium in dilute acid. A method for simulating potentiometric titrations is proposed, and this method suggests that the stoichiometric end point and the inflection point may not always correspond in the potentiometric titration of plutonium. A possible characteristic equation for the nitrite-plutonium reaction is illustrated, and the method of proportional equations is extended to the iron-plutonium reaction

  9. Cigarette smoke and plutonium

    International Nuclear Information System (INIS)

    Filipy, R.E.

    1985-01-01

    Autoradiographic techniques with liquid photographic emulsion and cellulose nitrate track-etch film are being used to investigate the spatial distribution of inhaled plutonium in the lungs of beagle dogs exposed to cigarette smoke or to the plutonium aerosol only. More plutonium than expected was detected on the inner surfaces of bronchi, and particles were observed beneath the bronchial mucosa. 2 figures, 2 tables

  10. Optimizing Plutonium stock management

    International Nuclear Information System (INIS)

    Niquil, Y.; Guillot, J.

    1997-01-01

    Plutonium from spent fuel reprocessing is reused in new MOX assemblies. Since plutonium isotopic composition deteriorates with time, it is necessary to optimize plutonium stock management over a long period, to guarantee safe procurement, and contribute to a nuclear fuel cycle policy at the lowest cost. This optimization is provided by the prototype software POMAR

  11. Treatment of plutonium contaminations

    International Nuclear Information System (INIS)

    Lafuma, J.

    1983-01-01

    Three kinds of plutonium contaminations were considered: skin contamination; contaminated wounds; contamination by inhalation. The treatment of these contaminations was studied for insoluble (oxide and metal forms) and soluble plutonium (complexes). The use of DTPA and therapeutic problems encountered with stable plutonium complexes were analyzed. The new possibilities of internal decontamination using Puchel and LICAM were evaluated [fr

  12. Plutonium, nuclear fuel; Le plutonium, combustible nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Grison, E [Commissariat a l' Energie Atomique, Fontenay aux Roses (France). Centre d' Etudes Nucleaires, Saclay

    1960-07-01

    A review of the physical properties of metallic plutonium, its preparation, and the alloys which it forms with the main nuclear metals. Appreciation of its future as a nuclear fuel. (author) [French] Apercu sur les proprietes physiques du plutonium metallique, sa preparation, ses alliages avec les principaux metaux nucleaires. Consideration sur son avenir en tant que combustible nucleaire. (auteur)

  13. Plutonium economy. Plutonium-Wirtschaft

    Energy Technology Data Exchange (ETDEWEB)

    Traube, K

    1984-01-01

    The author expresses his opinion on the situation, describes the energy-economic setting, indicates the alternatives: fuel reprocessing or immediate long-term storage, and investigates the prospects for economic utilization of the breeder reactors. All the facts suggest that the breeder reactor will never be able to stand economic competition with light-water reactors. However, there is no way to prove the future. It is naive to think that every doubt could and must be removed before stopping the development of breeder reactors - and thus also the reprocessing of the fuel of light-water reactors. On the basis of the current state of knowledge an unbiased cost-benefit-analysis can only lead to the recommendation to stop construction immediately. But can 'experts', who for years or even decades have called for and supported the development of breeder reactors be expected to make an unbiased analysis. Klaus Traube strikes the balance of the state Germany's nuclear economy is in: although there is no chance of definitively abandoning that energy-political cul-de-sac, no new adventures must be embarked upon. Responsible handling of currently used nuclear technology means to give up breeder technology and waive plutonium economy. It is no supreme technology with the aid of which structural unemployment or any other economic problem could be solved.

  14. Formation and properties of radiation-induced defects and radiolysis products in lithium orthosilicate

    Energy Technology Data Exchange (ETDEWEB)

    Tiliks, J.E.; Kizane, G.K.; Supe, A.A.; Abramenkovs, A.A.; Tiliks, J.J. (Latvian Univ., Riga (Latvia)); Vasiljev, V.G. (Acad. A.A. Bochvar Inst. of Inorganic Materials, Moscow (USSR))

    1991-12-01

    Formation and properties of radiation-induced defects and radiolysis products in polycrystalline powders and ceramic pellets of Li{sub 4}SiO{sub 4} were studied under the effect of various types of ionizing irradiation ({gamma} quants, accelerated electrons, reactor irradiation), humidity, temperature, impurities in the samples, etc. The content of radiation defects and radiolysis products poorly depends on irradiation type, dose rate, admixture elements. The concentration of defects highly depends on the temperature of irradiation, humidity, granural size. Empirical dependence of radiolysis degree {alpha} on the dose was found: {alpha}=5x10{sup -2}xD{sup 0.5} for {gamma} and electron irradiation (T{sub rad}=300-350 K) and {alpha}=5x10{sup -3}xD{sup 0.5} for reactor radiation (T{sub rad}=700-800 K); {alpha} - matrix dissociation degree (in %); D - dose (in MGy). Colloidal lithium and silicon, lithium and silicon oxides, and O{sub 2} are the final products of radiolysis. Radiation-induced defects change tritium thermo-extraction parameters, deteriorate mechanical, thermo-physical and electric properties of ceramics. (orig.).

  15. Ultra trace plutonium isotopic analyse by thermo ionization mass spectrometry

    International Nuclear Information System (INIS)

    Liu Xuemei; Long Kaiming; Yang Tianli

    2008-06-01

    An anion exchange combined with TTA extraction decontamination method was established. The nanogram quantity Plutonium was separated from milligram uranium and the decontamination coefficient achieved 10 7 , the recovery coefficient >95%. The active carbon powder was chosen as the ionization intensifier to increase the plutonium ion flow. Used 6.7 pg Plutonium standard as sample to measured by TIMS and the RSD of the 240 Pu/ 239 Pu ≤3.6%. (authors)

  16. The handling of plutonium hexafluoride (1962); Manipulation de l'hexafluorure de plutonium (1962)

    Energy Technology Data Exchange (ETDEWEB)

    Berard, Ph [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1961-11-15

    The major problem posed in this work is the instability of plutonium hexafluoride. The influence of various factors on the decomposition of the fluoride has been studied: physical aspect of the walls, nature of the metal and its pretreatment, influence of the temperature. A means of detecting plutonium-239 in a metallic apparatus by {gamma}-ray counting has been developed; the sensitivity is of the order of half a milligram, but the precision is very low (about 50 per cent). Yields of over 95 per cent have been obtained for the transfer of plutonium during the preparation and sublimation of the hexafluoride. This study confirms the possibility of using plutonium hexafluoride for the extraction of plutonium from irradiated fuel elements by a dry method. (author) [French] Le probleme majeur de cette etude a ete l'instabilite de l'hexafluorure de plutonium. Nous avons etudie l'influence de divers facteurs sur la decomposition de l'hexafluorure: aspect physique des parois, nature du metal et de son pretraitement, influence de la temperature. Nous avons mis au point un mode de detection du plutonium-239 dans un appareillage metallique par comptage du rayonnement {gamma}; la sensibilite est de l'ordre du demi-milligramme, mais la precision est tres faible (50 pour cent environ). Nous avons obtenu des rendements depassant 95 pour cent dans le transfert du plutonium au cours de la fabrication et de la sublimation de l'hexafluorure. Cette etude confirme la possibilite d'utiliser l'hexafluorure de plutonium dans l'extraction du plutonium des combustibles irradies par voie seche. (auteur)

  17. Progress on laboratory studies of the immobilisation of plutonium contaminated materials (pcm)

    International Nuclear Information System (INIS)

    Awmack, A.F.; Hemingway, K.

    1984-09-01

    This report describes progress on laboratory scale investigations into immobilisation of Plutonium Contaminated Materials for the year ending August 1984. The work is a continuation of that previously reported though some new work is also included. The samples tested were shredded plastic materials and latex. Three areas of work are covered (1) ISO Leach Tests (2) Radiolysis and degradation of organic materials (3) Equilibrium Leach Tests. (author)

  18. The plutonium society

    International Nuclear Information System (INIS)

    Mez, L.; Richter, M.

    1981-01-01

    The lectures of an institute are reported on, which took place between 25th and 27th January 1980 in Berlin. The subsequent public panel discussion with representations from the political parties is then documentated in a few press-reports. The themes of the 8 lectures are: views and facts on plutonium, plutonium as an energy resource, military aspects of the production of plutonium, economic aspects of the plutonium economy, the position of the trade unions on the industrial reconversion, the alleged inevitability of a plutonium society and the socio-political alternatives and perspectives of nuclear waste disposal. (UA) [de

  19. The use of plutonium

    International Nuclear Information System (INIS)

    Marshall, W.

    1980-01-01

    The use of plutonium as a vital energy source producing maximum economic benefit with minimum proliferation risks is discussed. Having considered the production of plutonium, several possible plutonium fuel cycle options are identified and the economic value to be attached to plutonium for each examined. It is shown how the use of plutonium in fast reactors gives an opportunity for a non-proliferation policy not available when plutonium is used only in thermal reactors. From the technical considerations reviewed concerning plutonium and fast reactors it is shown that an economic regime involving international trade in spent thermal reactor fuel is possible which benefits equally those countries with fast reactors and those without and also assists in avoiding the proliferation of nuclear weapons. (U.K.)

  20. Calculating the plutonium in spent fuel elements

    International Nuclear Information System (INIS)

    Barnham, Keith

    1992-01-01

    Many members of the public are concerned about plutonium. They are worried about its environmental, health and proliferation risks. Fundamental to all such considerations are two related questions: how much plutonium do nuclear reactors produce ? and how accurately do the relevant authorities know these production figures ? These two questions have been studied with particular reference to the UK civil Magnox reactors. In 1990 these were still the only UK civil reactors whose spent fuel had been reprocessed to extract plutonium in routine production. It has not been possible to conclude that the relevant government industry and safeguard authorities are aware of how much plutonium these reactors produce and that the figures are known to the highest achievable accuracy. To understand why, this chapter will outline some of the history of the attempts to get answers to these two questions. (author)

  1. Direct reduction of plutonium from dicesium hexachloroplutonate

    International Nuclear Information System (INIS)

    Averill, W.A.; Boyd, T.E.

    1991-01-01

    The Rocky Flats Plant produces dicesium hexachloroplutonate (DCHP) primarily as a reagent in the molten salt extraction of americium from plutonium metal. DCHP is precipitated from aqueous chloride solutions derived from the leaching of process residues with a high degree of selectivity. DCHP is a chloride salt of plutonium, while the traditional aqueous precipitate is a hydrated oxide. Plutonium metal preparation from the oxide involves either the conversion of oxide to a halide followed by metallothermic reduction or direct reduction of the oxide using a flux. Either method generates at least three times as much radioactively contaminated waste as metal produced. Plutonium concentration by DCHP precipitation, however, produces a chloride salt that can be reduced using calcium metal at a temperature of approximately 1000K. In this paper the advantages and limitations of this process are discussed

  2. Plutonium Chemistry in the UREX Separation Processes

    International Nuclear Information System (INIS)

    Paulenova, Alena; Vandegrift, George F. III; Czerwinski, Kenneth R.

    2009-01-01

    The objective of the project is to examine the chemical speciation of plutonium in UREX+ (uranium/tributylphosphate) extraction processes for advanced fuel technology. Researchers will analyze the change in speciation using existing thermodynamics and kinetic computer codes to examine the speciation of plutonium in aqueous and organic phases. They will examine the different oxidation states of plutonium to find the relative distribution between the aqueous and organic phases under various conditions such as different concentrations of nitric acid, total nitrates, or actinide ions. They will also utilize techniques such as X-ray absorbance spectroscopy and small-angle neutron scattering for determining plutonium and uranium speciation in all separation stages. The project started in April 2005 and is scheduled for completion in March 2008.

  3. Plutonium in nature; Le plutonium dans la nature

    Energy Technology Data Exchange (ETDEWEB)

    Madic, C.

    1994-12-31

    Plutonium in nature comes from natural sources and anthropogenic ones. Plutonium at the earth surface comes principally from anthropogenic sources. It is easily detectable in environment. The plutonium behaviour in environment is complex. It seems necessary for the future to reduce releases in environment, to improve predictive models of plutonium behaviour in geosphere, to precise biological impact of anthropogenic plutonium releases.

  4. X-ray diffraction study of pure plutonium under pressure

    Energy Technology Data Exchange (ETDEWEB)

    Faure, Ph. [CEA, Valduc, F-21120 Is-sur-Tille (France)], E-mail: philippe.faure@cea.fr; Genestier, C. [CEA, Valduc, F-21120 Is-sur-Tille (France)

    2009-03-15

    Atomic volume and bulk modulus represent basic cohesion properties of a material and are therefore linked to many other physical properties. However, large discrepancies are found in the literature regarding values for the bulk modulus of pure plutonium ({alpha}-phase). New X-ray diffraction measurements of plutonium in diamond anvil cell are presented and the isothermal bulk modulus is extracted.

  5. Radiolysis of concentrated nitric acid solutions

    International Nuclear Information System (INIS)

    Nagaishi, R.; Jiang, P.Y.; Katsumura, Y.; Domae, M.; Ishigure, K.

    1995-01-01

    A study on electron pulse- and 60 Co γ-radiolysis of concentrated nitric acid and nitrate solutions has been carried out to elucidate the radiation induced reactions taking place in the solutions. Dissociation into NO 2 - and O( 3 P) was proposed as a direct action of the radiation on nitrate and gave the G-values were dependent on the chemical forms of nitrate: g s2 (-NO 3 - )=1.6 and g s2 (-HNO 3 )=2.2 (molecules/100eV). Based on the experimental yields of HNO 2 and reduced Ce IV , the primary yields of radiolysis products of water, g w , were evaluated to clarify the effects of nitrate on spur reactions of water in various nitrate solutions. (author)

  6. Robotic sample preparation for radiochemical plutonium and americium analyses

    International Nuclear Information System (INIS)

    Stalnaker, N.; Beugelsdijk, T.; Thurston, A.; Quintana, J.

    1985-01-01

    A Zymate robotic system has been assembled and programmed to prepare samples for plutonium and americium analyses by radioactivity counting. The system performs two procedures: a simple dilution procedure and a TTA (xylene) extraction of plutonium. To perform the procedures, the robotic system executes 11 unit operations such as weighing, pipetting, mixing, etc. Approximately 150 programs, which require 64 kilobytes of memory, control the system. The system is now being tested with high-purity plutonium metal and plutonium oxide samples. Our studies indicate that the system can give results that agree within 5% at the 95% confidence level with determinations performed manually. 1 ref., 1 fig., 1 tab

  7. Pulse radiolysis - new approaches to the classical technique

    Energy Technology Data Exchange (ETDEWEB)

    Zagorski, Z P [Institute of Nuclear Research, Warsaw (Poland)

    1973-01-01

    The present status of classical pulse radiolysis is described as well as trends in the further development of this technique (the investigation of radiolysis with nano- and picoseconds time resolution, new optica and electrochemical methods of intermediate species detection). The attention is concentrated on experimental difficulties of particular versions and the achievements are reviewed critically. This paper is the background for experiments being performed in the Institute of Nuclear Research on new techniques of pulse radiolysis.

  8. Characterisation and activation of catalysts for recombination of radiolysis gas

    International Nuclear Information System (INIS)

    Bolz, Michael; Koehler, Jan; Schorle, Rolf; Helf, Achim

    2011-01-01

    Radiolysis gas is produced by radiolysis of cooling water during the operation of boiling water reactors. Small amounts of radiolysis gas can accumulate at dead ends of pipes in the water-steam circuit. Under certain conditions, it can accumulate even to higher concentrations. To avoid these accumulations, small catalysts are built in. As part of a diploma thesis, the catalysts were analysed and characterised. (orig.)

  9. Fundamental Aspects of Water Coolant Radiolysis

    International Nuclear Information System (INIS)

    Christensen, Hilbert

    2006-04-01

    The current state of knowledge of radiolysis in Light Water Reactors (LWR) is presented in this report. High-temperature data for rate constants and primary radiolysis yields have been collected and are shown in tables. Data from different sources have been compared and based on this recommended values have been selected. There is generally a good agreement between g-values for gamma-radiation at ambient temperature from different sources. There are larger discrepancies between results for primary yields from fast neutrons and also for g-values at reactor temperatures. Complete reaction mechanisms, including rate constants at reactor temperatures, from different sources are discussed and shown in tables. Experimentally determined activation energies are also shown, including the temperature range within which they have been determined. In normal cases rate constants at high temperature have been calculated from the rate constant at ambient temperature and the activation energy. Exceptions from this rule are shown and uncertainties have been discussed. The results of a number of radiolysis calculations, carried out for reactor temperatures, are also shown. The results of some sensitivity analyses are discussed. It has been shown that results from radiolysis calculations are rather sensitive to the rate constant ratio k(OH + H 2 )/(k(OH + H 2 O 2 ). The first reaction leads to recombination, whereas the last reaction leads to decomposition. In some cases reactions which are unimportant at ambient temperature may play a role at reactor temperatures. This may be the case for reactions with a low rate constant at ambient temperature in combination with a high activation energy

  10. Radiolysis of DNA-protein complexes

    Energy Technology Data Exchange (ETDEWEB)

    Begusova, Marie [Department of Radiation Dosimetry, Nuclear Physics Institute, Na Truhlarce 39/64, CZ-18086, Prague 8 (Czech Republic)]. E-mail: begusova@ujf.cas.cz; Gillard, Nathalie [Centre de Biophysique Moleculaire, CNRS, rue Charles-Sadron, F-45071 Orleans Cedex 2 (France); Sy, Denise [Centre de Biophysique Moleculaire, CNRS, rue Charles-Sadron, F-45071 Orleans Cedex 2 (France); Castaing, Bertrand [Centre de Biophysique Moleculaire, CNRS, rue Charles-Sadron, F-45071 Orleans Cedex 2 (France); Charlier, Michel [Centre de Biophysique Moleculaire, CNRS, rue Charles-Sadron, F-45071 Orleans Cedex 2 (France); Spotheim-Maurizot, Melanie [Centre de Biophysique Moleculaire, CNRS, rue Charles-Sadron, F-45071 Orleans Cedex 2 (France)

    2005-02-01

    We discuss here modifications of DNA and protein radiolysis due to the interaction of these two partners in specific complexes. Experimental patterns of frank strand breaks (FSB) and alkali revealed breaks (ARB) obtained for DNA lac operator bound to the lac repressor and for a DNA containing an abasic site analog bound to the formamidopyrimidine-DNA glycosylase are reported. Experimental data are compared to predicted damage distribution obtained using the theoretical model RADACK.

  11. Radiolysis of DNA-protein complexes

    International Nuclear Information System (INIS)

    Begusova, Marie; Gillard, Nathalie; Sy, Denise; Castaing, Bertrand; Charlier, Michel; Spotheim-Maurizot, Melanie

    2005-01-01

    We discuss here modifications of DNA and protein radiolysis due to the interaction of these two partners in specific complexes. Experimental patterns of frank strand breaks (FSB) and alkali revealed breaks (ARB) obtained for DNA lac operator bound to the lac repressor and for a DNA containing an abasic site analog bound to the formamidopyrimidine-DNA glycosylase are reported. Experimental data are compared to predicted damage distribution obtained using the theoretical model RADACK

  12. Gamma radiolysis effects on basalt groundwater

    International Nuclear Information System (INIS)

    Gray, W.J.

    1983-10-01

    Gamma radiolysis of basalt groundwater containing 700 ppM methane produces a milky liquid that is a suspension of fine particles of a high molecular weight hydrocarbon somewhat like polyethylene. The ability of these polymers to chelate with, or otherwise sorb, metal ions from aqueous solution was measured using Cu +2 as a representative cation. Values in the range 0.3 to 0.8 millimoles of Cu per liter of solution were found. 5 references, 2 figures, 2 tables

  13. Radiolysis of methylene blue studied by ESR

    International Nuclear Information System (INIS)

    Contineau, M.; Iliescu, C.; Ciureanu, M.

    1983-01-01

    Electron spin resonance spectra have been used to gain information on the mechanism of radiolysis of aqueous solutions of methylene blue. The identity and behaviour of the semiquinone radicals formed as intermediate reduction products were discussed for strongly acid and for alcaline solutions. In order to obtain information on the radiolytic mechanism in strongly acidic media, irradiation was performed in the presence of various types of scavengers: sodium formate, glucose, succinic acid, hydroquinone and D,L-α alanine. (author)

  14. Construction of ion beam pulse radiolysis system

    Energy Technology Data Exchange (ETDEWEB)

    Chitose, Norihisa; Katsumura, Yosuke; Domae, Masafumi; Ishigure, Kenkichi; Murakami, Takeshi [Tokyo Univ. (Japan)

    1996-10-01

    An ion beam pulse radiolysis system has been constructed at HIMAC facility. Ion beam of 24 MeV He{sup 2+} with the duration longer than 1 {mu}s is available for irradiation. Three kinds of aqueous solutions, (C{sub 6}H{sub 5}){sub 2}CO, NaHCO{sub 3} and KSCN, were irradiated and the absorption signals were observed. (author)

  15. Radiolysis of solutions in anthraquinone derivatives

    International Nuclear Information System (INIS)

    Kriminskaya, Z.K.

    1996-01-01

    Stationary radiolysis of anthraquinones in solutions of ethanol, propanol-2 and water by gamma-radiation (dose rate of 1.6 Gy/s) is studied. It is shown that anthraquinones are reduced in the above solutions up to anthrahydroquinones, whereby all reduction particles participate in the reduction process. The reverse process of the post-radiation oxidation of anthrahydroquinones up to anthraquinones is a radical process

  16. Development of subpicosecond pulse radiolysis system

    International Nuclear Information System (INIS)

    Kozawa, T.; Saeki, A.; Okamoto, K.; Numata, Y.; Kaseda, K.; Yamamoto, T.; Suemine, S.; Yoshida, Y.; Tagawa, S.

    2000-01-01

    Subpicosecond pulse radiolysis system was developed to elucidate the primary processes of radiation chemistry in the time region of femtosecond. The system consists of a femtosecond electron linac as an irradiation source, a femtosecond laser as an analyzing light and a jitter compensation system which was designed to reduce the effect of jitter between an electron pulse and a laser pulse on the time resolution. The time resolution of 800 fs was achieved. (author)

  17. Structural analysis of radiolysis products of sennoside

    International Nuclear Information System (INIS)

    Song, Hyun Pa; Kim, Dong Ho

    2011-01-01

    The purpose of the present investigation was to analyze the structural changes of gamma irradiated sennoside B (prodrug) and to provide the possibility for application of irradiation to induce structural changes of the prodrugs for enhanced bioavailability. Sennoside B (200 ppm) in 70% methanol solution with or without the use of hydrogen peroxide or nitrous oxide gas was irradiated with 1, 3, 5, 10 and 20 kGy by gamma ray. The radiolysis products of gamma irradiated sennoside B solution were identified and determined by TLC, HPLC and LC-MS/MS. The sennoside B quantity decreased when irradiation dose increased and completely degraded at 10 kGy of irradiation. There was a linear relationship between the production of the radiolysis compounds and the absorbed dose of the gamma ray irradiated sennoside B. Radiolysis products yields increased on the addition of nitrous oxide gas into the sennoside B solution. No anthraquinone compounds were formed after irradiation of sennosie B. Scission of the O-glycoside bond and consequently formation of aglycone of sennoside B was observed

  18. The radiolysis of lithium oxide ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Tiliks, J; Supe, A; Kizane, G; Tiliks, J Jr [Latvia Univ., Riga (Latvia). Dept. of Chemistry; Grishmanov, V; Tanaka, S

    1998-03-01

    The radiolysis of Li{sub 2}O ceramics exposed to accelerated electrons (5 MeV) at 380 K was studied in the range of high absorbed doses up to 250 MGy. The formation of radiation defects (RD) and radiolysis products (RP) was demonstrated to occur simultaneously in the regions of (1) the regular crystalline lattice and (2) an enhanced content of the intrinsic defects and impurities. The production of the electronic RD and RP is more efficient in the region of the defected lattice than that at the site of the regular crystalline lattice. However, the stability of RD and RP formed in the region of the intrinsic defects is far less than those produced at the crystalline lattice, since most of the first mentioned RD and RP disappears with irradiation dose due to the radiation stimulated recombination. By this means the enhanced quantity of RD and RP is localized in the Li{sub 2}O ceramics irradiated to absorbed dose of 40-50 MGy, and hence this can influence the tritium release parameters. As soon as the intrinsic defects have been consumed in the production of RD and RP and the recombination of unstable electronic RD and RP takes place (at dose of {approx}100 MGy), the radiolysis of Li{sub 2}O ceramics occurs only at the crystalline lattice. Furthermore, the concentration of RD and RP increases monotonically and tends to the steady-state level. (author)

  19. Structural analysis of radiolysis products of sennoside

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hyun Pa; Kim, Dong Ho [KAERI, Daejeon (Korea, Republic of)

    2011-01-15

    The purpose of the present investigation was to analyze the structural changes of gamma irradiated sennoside B (prodrug) and to provide the possibility for application of irradiation to induce structural changes of the prodrugs for enhanced bioavailability. Sennoside B (200 ppm) in 70% methanol solution with or without the use of hydrogen peroxide or nitrous oxide gas was irradiated with 1, 3, 5, 10 and 20 kGy by gamma ray. The radiolysis products of gamma irradiated sennoside B solution were identified and determined by TLC, HPLC and LC-MS/MS. The sennoside B quantity decreased when irradiation dose increased and completely degraded at 10 kGy of irradiation. There was a linear relationship between the production of the radiolysis compounds and the absorbed dose of the gamma ray irradiated sennoside B. Radiolysis products yields increased on the addition of nitrous oxide gas into the sennoside B solution. No anthraquinone compounds were formed after irradiation of sennosie B. Scission of the O-glycoside bond and consequently formation of aglycone of sennoside B was observed

  20. Effect of nitrogen and oxygen on radiolysis of iodide solution

    Energy Technology Data Exchange (ETDEWEB)

    Karasawa, H; Endo, M [Hitachi Ltd., Power and Industrial System R+D Divisions, Ibaraki (Japan)

    1996-12-01

    The effect of nitrogen and oxygen on radiolysis of iodide solution was examined. Direct decomposition of nitrogen by {gamma}-radiation produced nitric acid to decrease a water pH. This resulted in the iodine formation in the radiolysis of iodide solution. Hydrogen peroxide was produced by the radiolysis of water containing oxygen. This worked a reducing agent to suppress the formation of iodine in the radiolysis of iodide solution. In the analytical model, fourteen iodine species were considered and reaction scheme consisted in 124 reactions. The analytical model could estimate the oxidation state of iodide ions. (author) 4 figs., 4 refs.

  1. Technical considerations and policy requirements for plutonium management

    International Nuclear Information System (INIS)

    Christensen, D.C.; Dinehart, S.M.; Yarbro, S.L.

    1995-01-01

    The goals for plutonium management have changed dramatically over the past few years. Today, the challenge is focused on isolating plutonium from the environment and preparing it for permanent disposition. In parallel, the requirements for managing plutonium are rapidly changing. For example, there is a significant increase in public awareness on how facilities operate, increased attention to environmental safety and health (ES and H) concerns, greater interest in minimizing waste, more emphasis on protecting material from theft, providing materials for international inspection, and a resurgence of interest in using plutonium as an energy source. Of highest concern, in the immediate future, is protecting plutonium from theft or diversion, while the national policy on disposition is debated. These expanded requirements are causing a broadening of responsibilities within the Department of Energy (DOE) to include at least seven organizations. An unavoidable consequence is the divergence in approach and short-term goals for managing similar materials within each organization. The technology base does exist, properly, safely, and cost effectively to extract plutonium from excess weapons, residues, waste, and contaminated equipment and facilities, and to properly stabilize it. Extracting the plutonium enables it to be easily inventoried, packaged, and managed to minimize the risk of theft and diversion. Discarding excess plutonium does not sufficiently reduce the risk of diversion, and as a result, long-term containment of plutonium from the environment may not be able to be proven to the satisfaction of the public

  2. Technical considerations and policy requirements for plutonium management

    International Nuclear Information System (INIS)

    Christensen, D.C.; Dinehart, S.M.; Yarbro, S.L.

    1996-01-01

    The goals for plutonium management have changed dramatically over the past few years. Today, the challenge is focused on isolating plutonium from the environment and preparing it for permanent disposition. In parallel, the requirements for managing plutonium are rapidly changing. For example, there is a significant increase in public awareness on how facilities operate, increased attention to environmental safety and health (ES and H) concerns, greater interest in minimizing waste, more emphasis on protecting material from theft, providing materials for international inspection, and a resurgence of interest in using plutonium as an energy source. Of highest concern, in the immediate future, is protecting plutonium from theft or diversion, while the national policy on disposition is debated. These expanded requirements are causing a broadening of responsibilities within the Department of Energy (DOE) to include at least seven organizations. An unavoidable consequence is the divergence in approach and short-term goals for managing similar materials within each organization. The technology base does exist, properly, safely, and cost effectively to extract plutonium from excess weapons, residues, waste, and contaminated equipment and facilities, and to properly stabilize it. Extracting the plutonium enables it to be easily inventoried, packaged, and managed to minimize the risk of theft and diversion. Discarding excess plutonium does not sufficient reduce the risk of diversion, and as a result, long-term containment of plutonium from the environment may not be able to be proven to the satisfaction of the public

  3. The first milligrams of plutonium

    International Nuclear Information System (INIS)

    Goldschmidt, B.

    1997-01-01

    A historical review of the development of the very first quantities of plutonium produced during World War II in the United States and in Canada, as remembered by the French nuclear chemist, Mr Goldschmidt, who participated to the various programs which were involved in the development of the atomic bomb, and to the first steps of the French atomic program after the war. Mr Goldschmidt worked especially on organic solvent extraction, with the selection, in 1945, of non volatile tri glycol dichloride, and the development of the Chalk River plant. In 1949, at the Bouchet plant, his team has isolated the first milligrams of French plutonium from uranium oxide; and in 1952, the PUREX process was developed

  4. An analytical method for the determination of plutonium in autopsy samples

    International Nuclear Information System (INIS)

    Santori, G.

    1983-01-01

    A sensitive method for the determination of plutonium in autopsy samples is described. After a suitable chemical pretreatment of the samples the plutonium is separated by extraction chromatography with tri-n-octylphosphine oxide (TOPO) supported on microporus polyethylene. After electrodeposition of plutonium the activity is counted by alpha spectroscopy. The global yield was 75-80%. The reagent blank activity was such to allow the determination of some femtocuries of plutonium

  5. Properties of plutonium

    International Nuclear Information System (INIS)

    Ahn, Jin Su; Yoon, Hwan Ki; Min, Kyung Sik; Kim, Hyun Tae; Ahn, Jong Sung; Kwag, Eon Ho; Ryu, Keon Joong

    1996-03-01

    Plutonium has unique chemical and physical properties. Its uniqueness in use has led to rare publications, in Korea. This report covers physical aspects of phase change of metal plutonium, mechanical properties, thermal conductivity, etc, chemical aspects of corrosion, oxidation, how to produce plutonium from spent fuels by describing various chemical treatment methods, which are currently used and were used in the past. It also contains characteristics of the purex reprocessing process which is the most widely used nowadays. And show processes to purify and metalize from recovered plutonium solution. Detection and analysis methods are introduced with key pints for handling, critical safety, toxicity, and effects on peoples. This report gives not only a general idea on what plutonium is, rather than deep technical description, but also basic knowledge on plutonium production and safeguards diversion from the view point of nonproliferation. 18 refs. (Author) .new

  6. Civil plutonium management

    International Nuclear Information System (INIS)

    Sicard, B.; Zaetta, A.

    2004-01-01

    During 1960 and 1970 the researches on the plutonium recycling in fast neutrons reactors were stimulated by the fear of uranium reserves diminishing. At the beginning of 1980, the plutonium mono-recycling for water cooled reactors is implementing. After 1990 the public opinion concerning the radioactive wastes management and the consequences of the disarmament agreements between Russia and United States, modified the context. This paper presents the today situation and technology associated to the different options and strategical solutions of the plutonium management: the plutonium use in the world, the neutronic characteristics, the plutonium effect on the reactors characteristics, the MOX behavior in the reactors, the MOX fabrication and treatment, the possible improvements to the plutonium use, the concepts performance in a nuclear park. (A.L.B.)

  7. Properties of plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Jin Su; Yoon, Hwan Ki; Min, Kyung Sik; Kim, Hyun Tae; Ahn, Jong Sung; Kwag, Eon Ho; Ryu, Keon Joong [Korea Atomic Energy Research Institute, Daeduk (Korea, Republic of)

    1996-03-01

    Plutonium has unique chemical and physical properties. Its uniqueness in use has led to rare publications, in Korea. This report covers physical aspects of phase change of metal plutonium, mechanical properties, thermal conductivity, etc, chemical aspects of corrosion, oxidation, how to produce plutonium from spent fuels by describing various chemical treatment methods, which are currently used and were used in the past. It also contains characteristics of the purex reprocessing process which is the most widely used nowadays. And show processes to purify and metalize from recovered plutonium solution. Detection and analysis methods are introduced with key pints for handling, critical safety, toxicity, and effects on peoples. This report gives not only a general idea on what plutonium is, rather than deep technical description, but also basic knowledge on plutonium production and safeguards diversion from the view point of nonproliferation. 18 refs. (Author) .new.

  8. World status report: plutonium

    International Nuclear Information System (INIS)

    Dircks, W.

    1992-01-01

    In a recent speech in Japan, the Deputy Director General of the International Atomic Energy Agency (IAEA) said that the economic case for reprocessing spent nuclear fuel had been severely eroded. An edited version of the speech is given. The changed prospects for nuclear energy is given as the reason why the demand for plutonium has declined sharply. The oil crisis of the 1970s reduced the demand for electric power and the economic justification for the use of recycled plutonium. The stockpile of isolated plutonium is growing rapidly giving rise to worries about its security. From this point of view, isolated plutonium is best kept in reactor fuel not separated out. In this connection the IAEA has offered to help in the storage of plutonium so that vigorous safety and security requirements are met. In Japan there is a debate about the plutonium which is dependent on the future of the fast breeder reactor programme. (UK)

  9. Progress on plutonium stabilization

    International Nuclear Information System (INIS)

    Hurt, D.

    1996-01-01

    The Defense Nuclear Facilities Safety Board has safety oversight responsibility for most of the facilities where unstable forms of plutonium are being processed and packaged for interim storage. The Board has issued recommendations on plutonium stabilization and has has a considerable influence on DOE's stabilization schedules and priorities. The Board has not made any recommendations on long-term plutonium disposition, although it may get more involved in the future if DOE develops plans to use defense nuclear facilities for disposition activities

  10. PLUTONIUM-ZIRCONIUM ALLOYS

    Science.gov (United States)

    Schonfeld, F.W.; Waber, J.T.

    1960-08-30

    A series of nuclear reactor fuel alloys consisting of from about 5 to about 50 at.% zirconium (or higher zirconium alloys such as Zircaloy), balance plutonium, and having the structural composition of a plutonium are described. Zirconium is a satisfactory diluent because it alloys readily with plutonium and has desirable nuclear properties. Additional advantages are corrosion resistance, excellent fabrication propenties, an isotropie structure, and initial softness.

  11. Cigarette smoke and plutonium

    International Nuclear Information System (INIS)

    Filipy, R.E.

    1983-01-01

    The major objective of this project is to obtain experimental data that are directly applicable to resolving the question of whether cigarette smokers are at greater risk than nonsmokers to potential health effects of inhaled plutonium. Because cigarette smokers constitute a large fraction of the population, a synergistic effect of plutonium and cigarette smoke might influence estimates of the health risk for plutonium and other transuranics released to the environment

  12. The first metallurgical tests on plutonium; Premiers essais metallurgiques sur le plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Grison, E; Abramson, R; Anselin, F; Monti, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    Metallic plutonium was first prepared in France in January 1956, as soon as we had access to quantities of the order of several grams of plutonium, which had been extracted from the rods of the pile EL2 at Saclay. Since up to the present this reactor, of thermal power 2 000 kW, has been our only source of plutonium, we have so far only worked on experimental quantities sufficient for the basic tests but not for tests on a scale of possible applications. It is this work, carried out during this phase of preliminary research, which is described below. With the starting up of the plutonium extraction plant at Marcoule, where the reactor G1 has been operating at power for more than a year, we shall go on next to a another order of magnitude which will allow the manufacture and experimentation of prototype fuel elements. (author) [French] La premiere elaboration de plutonium metallique en France fut faite en janvier 1956, des que nous pumes disposer de quantites de plutonium de l'ordre de quelques grammes, qui avaient ete retires des barreaux de la pile EL2 de Saclay. Ce reacteur, d'une puissance thermique de 2 000 kW, ayant ete jusqu'a present notre seule source de plutonium, nous n'avons encore travaille que sur des quantites experimentales suffisantes pour les essais de base, mais non pour des essais a l'echelle d'applications possibles. Ce sont les travaux effectues pendant cette phase de recherches preliminaires qui seront evoques ci-dessous. Avec la mise eu route de l'usine d'extraction de plutonium de Marcoule, ou le reacteur G1 fonctionne en puissance depuis plus d'un an, nous allons passer prochainement a un autre ordre de grandeur, qui nous permettra la fabrication et l'experimentation d'elements combustibles prototypes. (auteur)

  13. Perspective on plutonium

    International Nuclear Information System (INIS)

    Sun, L.S.

    1993-01-01

    This paper is intended as a brief overview on the element plutonium. Plutonium is the first primarily man-made element to play a significant role not only in technological development, but also in the economic growth of many countries. The importance of plutonium centers around its enormous energy making it ideal for wide-scale use in reactors, while the nuclear industry continues to work toward improving safety and efficiency of plutonium as a reactor fuel politicians and the public still debate over the safety and benefits of nuclear power. (30 refs.)

  14. Chemical characterization of local and stratospheric plutonium in Ohio soils

    International Nuclear Information System (INIS)

    Muller, R.N.

    1978-01-01

    The chemical nature of plutonium derived from stratospheric fallout and industrial sources was studied in three agricultural soils. The majority of the soil plutonium was associated with a reductant-soluble, hydrous oxide phase that, under most conditions of terrestrial ecosystems, remains essentially immobile. The proportion of plutonium associated with organic matter (0.1N NaOH-extractable) varied among soils, and increased with decreasing particle size in the same soil. In a soil containing 238 Pu from a local fabrication facility and 239 , 240 Pu from stratospheric fallout, isotopic ratios between the NaOH-extractable and residual phases were essentially constant, indicating that, in these soils, plutonium from both sources behaves similarly. The distribution of soil plutonium with particle size appears to be most directly related to the mass of the soil particle

  15. The analysis of radiolysis impurities in 18F-FDG and methods of repurification

    International Nuclear Information System (INIS)

    Jinming Zhang; Yungang Li; Jian Liu; Xiaojun Zhang; Jiahe Tian

    2010-01-01

    To investigate the radio impurity in the radiolysis of 18 F-FDG at high radiodose and radioconcentrated solutions and develop methods of repurification. The radiolysis of 18 F-FDG was analyzed by TLC. The radio-impurity was confirmed by biodistribution and small animal PET/CT studies. 18 F-FDG was unstable at high radioconcentration over 37 GBq/mL or under basic condition. TLC, biodistribution and PET/CT all indicated that the main autoradiolysis byproduct was free fluoride ion. The radiolyzed 18 F-FDG was repurified by solid-phase extraction (SPE) column. The repurified 18 F-FDG had a radiochemical purity (RCP) of over 99% and significantly lower bone uptake than that was before repurification (P = 0.0003). There was a positive correlation between the recovery yield and the purity of 18 F-FDG (R 2 = 0.66). (author)

  16. Oxidizing dissolution of spent MOX47 fuel subjected to water radiolysis: Solution chemistry and surface characterization by Raman spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Jegou, C., E-mail: christophe.jegou@cea.f [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Caraballo, R.; De Bonfils, J.; Broudic, V.; Peuget, S. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France); Vercouter, T. [Commissariat a l' Energie Atomique (CEA), Saclay Reasearch Center, B.P. 11, F-91191 Gif-sur-Yvette Cedex (France); Roudil, D. [Commissariat a l' Energie Atomique (CEA), Marcoule Reasearch Center, B.P. 17171, F-30207 Bagnols-sur-Ceze Cedex (France)

    2010-04-01

    The mechanisms of oxidizing dissolution of spent MOX fuel (MIMAS TU2 (registered) ) subjected to water radiolysis were investigated experimentally by leaching spent MOX47 fuel samples in pure water at 25 deg. C under different oxidizing conditions (with and without external gamma irradiation); the leached surfaces were characterized by Raman spectroscopy. The highly oxidizing conditions resulting from external gamma irradiation significantly increased the concentration of plutonium (Pu(V)) and uranium (U(VI)) compared with a benchmark experiment (without external irradiation). The oxidation behavior of the plutonium-enriched aggregates differed significantly from that of the UO{sub 2} matrix after several months of leaching in water under gamma irradiation. The plutonium in the aggregates appears to limit fuel oxidation. The only secondary phases formed and identified to date by Raman spectroscopy are uranium peroxides that generally precipitate on the surface of the UO{sub 2} grains. Concerning the behavior of plutonium, solution analysis results appear to be compatible with a conventional explanation based on an equilibrium with a Pu(OH){sub 4(am)} phase. The fission product release - considered as a general indicator of matrix alteration - from MOX47 fuel also increases under external gamma irradiation and a change in the leaching mode is observed. Diffusive leaching was clearly identified, coinciding with the rapid onset of steady-state actinide concentrations in the bulk solution.

  17. Picosecond pulse radiolysis studies to understand the primary processes in radiolysis

    International Nuclear Information System (INIS)

    Jonah, C.D.; Lewis, M.A.

    1984-01-01

    The use of pulse radiolysis to learn about processes which occur before the beginning of chemical times is discussed. Two examples, the distance distribution of positive and negative ions in hydrocarbons, and the state of the dry electron are discussed in detail

  18. Picosecond pulse radiolysis studies to understand the primary processes in radiolysis

    Energy Technology Data Exchange (ETDEWEB)

    Jonah, C.D.; Lewis, M.A.

    1984-01-01

    The use of pulse radiolysis to learn about processes which occur before the beginning of chemical times is discussed. Two examples, the distance distribution of positive and negative ions in hydrocarbons, and the state of the dry electron are discussed in detail.

  19. EXPECTED IMPACT OF HANFORD PROCESSING ORGANICS OF PLUTONIUM DURING TANK WASTE SLUDGE RETRIEVAL

    International Nuclear Information System (INIS)

    TROYER, G.L.; WINTERS, W.I.

    2004-01-01

    This document evaluates the potential for extracting plutonium from Hanford waste tanks into residual organic solvents and how this process may have an impact on criticality specifications during the retrieval of wastes. The two controlling factors for concentrating plutonium are the solubility of the plutonium in the wastes and the extraction efficiency of the potential organic extractants that may be found in these wastes. Residual Hanford tank sludges contain plutonium in solid forms that are expected to be primarily insoluble Pu(IV) hydroxides. Evaluation of thermodynamic Pourbaix diagrams, documentation on solubility studies of various components in waste tank matrices, and actual analysis of plutonium in tank supernates all indicate that the solubility of Pu in the alkaline waste is on the order of 10 -6 M. Based on an upper limit plutonium solubility of 10 -5 M in high pH and a conservative distribution coefficient for organic extractants of a 0 for plutonium in 30% TBP at 0.07 M HNO 3 ), the estimated concentration for plutonium in the organic phase would be -7 M. This is well below the process control criteria. A significant increase in plutonium solubility or the E a o would have to occur to raise this concentration to the 0.01 M concern level for organics. Measured tank chemical component values, expected operating conditions, and the characteristics of the expected chemistry and extraction mechanisms indicate that concentration of plutonium from Hanford tank residual sludges to associated process organic extractants is significantly below levels of concern

  20. Radiolysis characterization of chloramphenicol in powder and in eye ointment

    International Nuclear Information System (INIS)

    Hong, L.; Altorfer, H.R.

    2005-01-01

    The effects of γ-radiation sterilization on chloramphenicol, in both pure powder state and petrolatum eye ointment, were investigated with high performance liquid chromatography. The content of chloramphenicol decreases by 1.0% in powder state and by 1.2% in eye ointment at the reference radiation dose of 25 kGy. The profile of chloramphenicol radiolysis products in powder state differs from that in eye ointment. It was found that microenvironment of chloramphenicol molecule is a key factor governing the radiolysis of chloramphenicol in powder state. Solvent residues in chloramphenicol powder could change the radiolysis behavior of chloramphenicol. The solvents, having good solubility for chloramphenicol, promote radiolytic hydrolysis of chloramphenicol, but the converses do not. Inert gas purging or diffusion by exposing in absorbent is efficient method to prevent chloramphenicol powder from radiolysis. The influence of the presence of oxygen was explored. Oxygen plays a role of scavenger and diminishes radiolysis of chloramphenicol. It was found that Nactyl-L-cysteine can protection chloramphenicol in eye ointment from radiolysis. Hydrophobic radiolysis products of chloramphenicol were observed in eye ointment part. Using scavengers and lower irradiation can be strategies to resist radiolysis of chloramphenicol in petrolatum eye ointment. (author)

  1. Pulse radiolysis of 9,10-anthraquinone in methanol

    International Nuclear Information System (INIS)

    Mayer, J.; Krasiukianis, R.

    1990-01-01

    The reactions of anthraquinone with intermediates in methanol (e 2 - , . CH 2 O - , . CH 2 OH) were investigated using γ-radiolysis and pulse radiolysis method. The anthraquinone radical anions are reactive towards O 2 (ca 3 x 10 8 mol -1 dm 3 s -1 ) and can disproportionate giving corresponding dianion. (author)

  2. Aqueous Chloride Operations Overview: Plutonium and Americium Purification/Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, Kyle Shelton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kimball, David Bryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Skidmore, Bradley Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-28

    These are a set of slides intended for an information session as part of recruiting activities at Brigham Young University. It gives an overview of aqueous chloride operations, specifically on plutonium and americium purification/recovery. This presentation details the steps taken perform these processes, from plutonium size reduction, dissolution, solvent extraction, oxalate precipitation, to calcination. For americium recovery, it details the CLEAR (chloride extraction and actinide recovery) Line, oxalate precipitation and calcination.

  3. Cigarette smoke and plutonium

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    The overall objective of this study is to determine whether cigarette smoking increases the probability of plutonium-induced lung cancer. Initial experiments, designed to characterize the effect of chronic cigarette smoke exposure on pulmonary clearance of plutonium aerosols, are described

  4. Plutonium valence state distributions

    International Nuclear Information System (INIS)

    Silver, G.L.

    1974-01-01

    A calculational method for ascertaining equilibrium valence state distributions of plutonium in acid solutions as a function of the plutonium oxidation number and the solution acidity is illustrated with an example. The method may be more practical for manual use than methods based upon polynomial equations. (T.G.)

  5. Ion beam pulse radiolysis system at HIMAC

    Energy Technology Data Exchange (ETDEWEB)

    Chitose, N; Katsumura, Y; Domae, M; Ishigure, K [Tokyo Univ. (Japan); Murakami, T

    1997-03-01

    An ion beam pulse radiolysis system has been constructed at HIMAC facility. Ion beam of 24MeV He{sup 2+} with the duration longer than 1 {mu}s is available for irradiation. Three kinds of aqueous solutions, (C{sub 6}H{sub 5}){sub 2}CO, NaHCO{sub 3}, and KSCN, were irradiated and the absorption signals corresponding to (C{sub 6}H{sub 5}){sub 2}CO{sup -}, CO{sub 3}{sup -}, and (SCN){sub 2}{sup -} respectively were observed. Ghost signals which interfere with the measurement are also discussed. (author)

  6. Pulse radiolysis of 6-aminophenalenone ethanolic solutions

    International Nuclear Information System (INIS)

    Semenova, G.V.; Kartasheva, L.I.; Ryl'kov, V.V.; Pikaev, A.K.

    1986-01-01

    Intermediates of 6-aminophenalenone radiolytic transformations in ethanol are investigated using pulse radiolysis method (5 and 8 MeV energy electrons, pulse duration is 2.3 μs and 15 ns respectively). Constants of reaction rate of e s and α-ethanolic radical with dye are measured (they are equal to (9.3±1.0)x10 9 and (1.1±0.2)x10 8 l/(molxs) respectively); optical and kinetic characteristics of products of their interaction are investigated. Mechanism of radiolytic transformations of this dye is proposed

  7. The determination of plutonium isotopes in environmental samples

    International Nuclear Information System (INIS)

    Siripirom, Lopchai.

    1983-01-01

    The concentration of plutonium in environmental samples such as soil, water, and surface air in the middle part of Thailand were studied. The surface air were collected only at the fifth floor of the Office of Atomic Energy for Peace (OAEP). Plutonium-242 was used as a tracer. Soil and air samples were dissolved by pyrosulphate fusion, and plutonium was co-precipitated with barium sulfate. Then dissolved the precipitate in perchloric acid. Plutonium was extracted out by using solvent bis-(2-ethylhexyl) phosphoric acid (HDEHP). Plutonium in water samples were coprecipitated with iron (III) hydroxide and were dissolved in 8 M. nitric acid. Then the plutonium was separated out by using anion exchange resin, Dowex 1x4. After the solvent extraction or the anion exchange, plutonium was coprecipitated with cerous hydroxide. The activities of plutonium were measured by a surface barrier detector for about 24 hours. Lower limit of detection for 1,440 minutes is 0.012 pCi. These studies showed that only plutonium-239, 240 was observed. The range of activities of plutonium-239, 240 in soil were 0.002-0.157 pCi/g (dry), in water were 0.1-81 f Ci/l, and in air were 7-330 a Ci/m 3 . However, the plutonium concentrations in these studies are far below the maximum permissible concentration (MPC) recommended by International Commission on Radiological Protection (ICRP) for general population which is equal to 3x10 8 f Ci/l of water and 5x10 6 a Ci/m 3 of air

  8. The toxicity of plutonium

    International Nuclear Information System (INIS)

    Crouse, P.L.

    1994-01-01

    Shipments of plutonium occasionally pass around the Cape coastal waters on its way to Japan from Europe. This invariably leads to a great deal of speculation of the dangers involved and of the extreme toxicity of plutonium, with the media and environmental groups claiming that (a) plutonium is the most toxic substance known to man, and that (b) a few kilograms of plutonium ground finely and dispersed in the atmosphere could kill every human being on earth. Comparisons with other poisons are drawn, e.g. common inorganic chemicals and biological agents. The original scare around the extraordinary toxicity of Pu seems to have started in 1974 with the claims of Tamplin and Cochran's hot particle theory about plutonium lodging in the sensitive portions of the lungs in small concentrated aggregates where they are much more effective in producing cancers. This theory, however, is regarded as thoroughly discredited by the experts in the field of radiotoxicity. 8 refs

  9. Plutonium storage criteria

    Energy Technology Data Exchange (ETDEWEB)

    Chung, D. [Scientech, Inc., Germantown, MD (United States); Ascanio, X. [Dept. of Energy, Germantown, MD (United States)

    1996-05-01

    The Department of Energy has issued a technical standard for long-term (>50 years) storage and will soon issue a criteria document for interim (<20 years) storage of plutonium materials. The long-term technical standard, {open_quotes}Criteria for Safe Storage of Plutonium Metals and Oxides,{close_quotes} addresses the requirements for storing metals and oxides with greater than 50 wt % plutonium. It calls for a standardized package that meets both off-site transportation requirements, as well as remote handling requirements from future storage facilities. The interim criteria document, {open_quotes}Criteria for Interim Safe Storage of Plutonium-Bearing Solid Materials{close_quotes}, addresses requirements for storing materials with less than 50 wt% plutonium. The interim criteria document assumes the materials will be stored on existing sites, and existing facilities and equipment will be used for repackaging to improve the margin of safety.

  10. Plutonium roundtable discussion

    International Nuclear Information System (INIS)

    Penneman, R.A.

    1982-01-01

    The roundtable discussion began with remarks by the chairman who pointed out the complicated nature of plutonium chemistry. Judging from the papers presented at this symposium, he noticed a pattern which indicated to him the result of diminished funding for investigation of basic plutonium chemistry and funding focused on certain problem areas. Dr. G.L. silver pointed to plutonium chemists' erroneous use of a simplified summary equation involving the disproportionation of Pu(EV) and their each of appreciation of alpha coefficients. To his appreciation of alpha coefficients. To his charges, Dr. J.T. Bell spoke in defense of the chemists. This discussion was followed by W.W. Schulz's comments on the need for experimental work to determine solubility data for plutonium in its various oxidation states under geologic repository conditions. Discussion then turned to plutonium pyrachemical process with Dana C. Christensen as the main speaker. This paper presents edited versions of participants' written version

  11. Plutonium storage phenomenology

    International Nuclear Information System (INIS)

    Szempruch, R.

    1995-12-01

    Plutonium has been produced, handled, and stored at Department of Energy (DOE) facilities since the 1940s. Many changes have occurred during the last 40 years in the sources, production demands, and end uses of plutonium. These have resulted in corresponding changes in the isotopic composition as well as the chemical and physical forms of the processed and stored plutonium. Thousands of ordinary food pack tin cans have been used successfully for many years to handle and store plutonium. Other containers have been used with equal success. This paper addressees the exceptions to this satisfactory experience. To aid in understanding the challenges of handling plutonium for storage or immobilization the lessons learned from past storage experience and the necessary countermeasures to improve storage performance are discussed

  12. Studies on radiolysis of amino acids, (3)

    International Nuclear Information System (INIS)

    Oku, Tadatake

    1978-01-01

    For the purpose of investigating the radiolysis of amino acids and the safeness to radiation, the radiolytic mechanism and radio-sensitivity of sulfur-containing amino acids in aqueous solution in the presence of air or in the atmosphere of nitrogen were studied. Aqueous solutions of L-methionine, cysteine (both 1mM) and L-cystine (0.3mM) were irradiated with γ-ray of 60 Co at the dose of 4.2 - 2,640 x 10 3 rad. The amino acids and the radiolytic products were determined with an amino acid analyzer. The volatile sulfur compounds formed from γ-irradiated methionine were estimated by a flame photometric detector-gas chromatograph. From the results obtained, G values of the radiolysis of sulfur-containing amino acids and the products were calculated, and the radiolytic mechanisms of methionine, cysteine and cystine were proposed. The radio-sensitivity of sulfur-containing amino acids was shown as follows: cysteine (C3-SH) > methionine (C5, -SCH 3 ) > cystine (C 6 , -S-S-). Off-flavor development from γ-irradiated methionine when oxidizing agent was added was less than that when reducing agent was added. (Kobatake, H.)

  13. Radiolysis of cyanocobalamin (vitamin B12)

    International Nuclear Information System (INIS)

    Juanchi, X.; Albarran, G.; Negron-Mendoza, A.

    2000-01-01

    Research on the radiolysis of vitamins is of considerable interest since these compounds are important nutritional constituents in foods and in dietetic supplements. In spite of these considerations there are few data and very often difficult to compare for the radiolytic behavior of vitamins. In this work we focused our attention on to the study of the radiolysis of cyanocobalamin (vitamin B 12 ) in solid state and in aqueous solutions. The procedure was followed by HPLC and UV-spectroscopy. The results obtained in aqueous solutions showed a dependence of the decomposition as a linear function of the dose. The G of decomposition for a 1x10 -5 M solution was 3.3. In the solid state the vitamin was very stable towards the irradiation in the conditions used in this study with a G=2.1x10 -3 . A study made with Serratia marcescens as a microbiological contaminant showed that at the sterilization dose there is a destruction of the vitamin in aqueous solution. In the solid state the degree of decomposition was 7%. (author)

  14. A review of the radiolysis of methane

    International Nuclear Information System (INIS)

    Norfolk, D.J.

    1975-08-01

    The review had three objectives: to determine the yields of the primary products and to describe the sequence of reactions in which they take part; to ascertain the effect on these reactions of changes in the physical state of the methane and the quantum energy of the radiation, and of the presence of chemically inert sensitisers; and to identify the situation most similar to the adsorbed phase radiolysis of methane on alumina, and so to predict the likely radiolytic reactions in this system. The main primary product yields in methane gas under γ-irradiation are estimated to be G(CH 4 +) approximately 1.75, G(CH 3 +) approximately 1.46, G(CH 3 ) approximately 1.4 and G(CH 2 ) approximately 1.0. The situation most similar to adsorbed phase radiolysis is inert gas sensitised photolysis at energies below 12.6eV. In this system the major primary process is homolytic dissociation of methane to CH 3 +H. (author)

  15. Hydrogen peroxide kinetics in water radiolysis

    Science.gov (United States)

    Iwamatsu, Kazuhiro; Sundin, Sara; LaVerne, Jay A.

    2018-04-01

    The kinetics of the formation and reaction of hydrogen peroxide in the long time γ- radiolysis of water is examined using a combination of experiment with model calculations. Escape yields of hydrogen peroxide on the microsecond time scale are easily measured with added radical scavengers even with substantial amounts of initial added hydrogen peroxide. The γ-radiolysis of aqueous hydrogen peroxide solutions without added radical scavengers reach a steady state limiting concentration of hydrogen peroxide with increasing dose, and that limit is directly proportional to the initial concentration of added hydrogen peroxide. The dose necessary to reach that limiting hydrogen peroxide concentration is also proportional to the initial concentration, but dose rate has a very small effect. The addition of molecular hydrogen to aqueous solutions of hydrogen peroxide leads to a decrease in the high dose limiting hydrogen peroxide concentration that is linear with the initial hydrogen concentration, but the amount of decrease is not stoichiometric. Proton irradiations of solutions with added hydrogen peroxide and hydrogen are more difficult to predict because of the decreased yields of radicals; however, with a substantial increase in dose rate there is a sufficient decrease in radical yields that hydrogen addition has little effect on hydrogen peroxide decay.

  16. Toxicology of plutonium

    International Nuclear Information System (INIS)

    Bair, W.J.

    1974-01-01

    Data are reviewed from studies on the toxicity of Pu in experimental animals. Of the several plutonium isotopes, only 238 Pu and 239 Pu have been studied well. Sufficient results have been obtained to show that the behavior of 238 Pu in biological systems and the resulting biological effects cannot be precisely predicted from studies of 239 Pu. This probably applies also to other radiologically important plutonium isotopes which have half-lives ranging from 45 days to 10 7 years and decay by β-emission, electron capture, and spontaneous fission, as well as by emission of α-particles. All the biological effects of plutonium described in this review are attributed to alpha-particle radiation emitted by the plutonium. However, since plutonium is a chemically active heavy metal, one cannot ignore the possibility of chemical toxicity of the low-specific-activity isotopes, 239 Pu, 242 Pu, and 244 Pu. The preponderance of our knowledge of plutonium toxicology has come from short-term studies of relatively high dosage levels in several animal species. The consequences of high-level internal exposures can be predicted with confidence in experimental animals and probably also in man. However, considering the care with which plutonium is handled in the nuclear industry, a high-level contamination event is unlikely. Considerably less is known about the long-term effects of low levels of contamination. (250 references) (U.S.)

  17. The radiolysis of CMPO: effects of acid, metal complexation and alpha vs. gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Bruce J. Mincher; Stephen P. Mezyk; Gary S. Groenewold

    2016-05-01

    Abstract The group actinide/lanthanide complexing agent octylphenylcarbamoylmethyl phosphine oxide (CMPO) has been examined for its radiation stability by measuring the kinetics of its reactions with free radicals in both the aqueous and organic phases for the free and metal-complexed ligand, identifying its degradation products for both alpha and gamma irradiation, measuring the effects on solvent extraction performance, and measuring the G-values for its degradation under various conditions. This includes the G-values for CMPO in the absence of, and in contact with the acidic aqueous phase, where it is shown that the acidic aqueous phase provides radio-protection for this ligand. It was found that both solvent and metal complexation affect the kinetics of the reaction of the •NO3 radical, a product of HNO3 radiolysis, with CMPO. For example, CMPO complexed with lanthanides has a rate constant for this reaction an order of magnitude higher than for the free ligand, and the reaction for the free ligand in the organic phase is about three times faster than in the aqueous phase. In steady state radiolysis kinetics it was determined that HNO3, although not NO3- anion, provides radio-protection to CMPO, with the G-value for its degradation decreasing with increasing acidity, until it was almost completely suppressed by irradiation in contact with 5 M HNO3. The same degradation products were produced by irradiation with alpha and gamma-sources, except that the relative abundances of these products varied. For example, the product of C-C bond scission was produced only in low amounts for gamma-radiolysis, but it was an important product for samples irradiated with a He ion beam. These results are compared to the new data appearing in the literature on DGA radiolysis, since CMPO and the DGAs both contain the amide functional group.

  18. Review of major plutonium pyrochemical technology

    International Nuclear Information System (INIS)

    Moser, W.S.; Navratil, J.D.

    1983-01-01

    The past twenty years have seen significant growth in the development and application of pyrochemical technology for processing of plutonium. For particular feedstocks and specific applications, non-aqueous high-temperature processes offer key advantages over conventional hydrometallurgical systems. Major processes in use today include: (1) direct oxide reduction for conversion of PuO 2 to metal, (2) molten salt extraction for americium removal from plutonium, (3) molten salt electrorefining for Pu purification, and (4) hydriding to remove plutonium from host substrates. This paper reviews current major pyrochemical processes from the classical calcination-hydrofluorination-bomb reduction sequence through new techniques under development. Each process is presented and brief descriptions of production equipment are given. 47 references, 5 figures

  19. ECP evaluation by water radiolysis and ECP model calculations

    Energy Technology Data Exchange (ETDEWEB)

    Hanawa, S.; Nakamura, T.; Uchida, S. [Japan Atomic Energy Agency, Tokai-mura, Ibaraki (Japan); Kus, P.; Vsolak, R.; Kysela, J. [Nuclear Research Inst. Rez plc, Rez (Czech Republic)

    2010-07-01

    In-pile ECP measurements data was evaluated by water radiolysis calculations. The data was obtained by using an in-pile loop in an experimental reactor, LVR-15, at the Nuclear Research Institute (NRI) in Czech Republic. Three types of ECP sensors, a Pt electrode, an Ag/AgCl sensor and a zirconia membrane sensor containing Ag/Ag{sub 2}O were used at several levels of the irradiation rig at various neutron flux and gamma rates. For water radiolysis calculation, the in-pile loop was modeled to several nodes following their design specifications, operating conditions such as flow rates, dose rate distributions of neutron and gamma-ray and so on. Concentration of chemical species along the water flow was calculated by a radiolysis code, WRAC-J. The radiolysis calculation results were transferred to an ECP model. In the model, anodic and cathodic current densities were calculated with combination of an electrochemistry model and an oxide film growth model. The measured ECP data were compared with the radiolysis/ECP calculation results, and applicability the of radiolysis model was confirmed. In addition, anomalous phenomenon appears in the in-pile loop was also investigated by radiolysis calculations. (author)

  20. Template measurement for plutonium pit based on neural networks

    International Nuclear Information System (INIS)

    Zhang Changfan; Gong Jian; Liu Suping; Hu Guangchun; Xiang Yongchun

    2012-01-01

    Template measurement for plutonium pit extracts characteristic data from-ray spectrum and the neutron counts emitted by plutonium. The characteristic data of the suspicious object are compared with data of the declared plutonium pit to verify if they are of the same type. In this paper, neural networks are enhanced as the comparison algorithm for template measurement of plutonium pit. Two kinds of neural networks are created, i.e. the BP and LVQ neural networks. They are applied in different aspects for the template measurement and identification. BP neural network is used for classification for different types of plutonium pits, which is often used for management of nuclear materials. LVQ neural network is used for comparison of inspected objects to the declared one, which is usually applied in the field of nuclear disarmament and verification. (authors)

  1. Plutonium Chemistry in the UREX+ Separation Processes

    Energy Technology Data Exchange (ETDEWEB)

    ALena Paulenova; George F. Vandegrift, III; Kenneth R. Czerwinski

    2009-10-01

    The project "Plutonium Chemistry in the UREX+ Separation Processes” is led by Dr. Alena Paulenova of Oregon State University under collaboration with Dr. George Vandegrift of ANL and Dr. Ken Czerwinski of the University of Nevada at Las Vegas. The objective of the project is to examine the chemical speciation of plutonium in UREX+ (uranium/tributylphosphate) extraction processes for advanced fuel technology. Researchers will analyze the change in speciation using existing thermodynamics and kinetic computer codes to examine the speciation of plutonium in aqueous and organic phases. They will examine the different oxidation states of plutonium to find the relative distribution between the aqueous and organic phases under various conditions such as different concentrations of nitric acid, total nitrates, or actinide ions. They will also utilize techniques such as X-ray absorbance spectroscopy and small-angle neutron scattering for determining plutonium and uranium speciation in all separation stages. The project started in April 2005 and is scheduled for completion in March 2008.

  2. Measurements of plutonium in environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    D' Alberti, F; Risposi, L [Instituto di Fisica Applicata, University of Milan, Milan (Italy)

    1996-01-01

    Within the activities connected with the start up of the PETRA Laboratory (Processo per l'Estrazione di Terre Rare ed Attinidi, i.e. process for extraction of rare earths and actinides), the Radiation Protection Unit of the J.R.C.-Ispra has carried out a well planned set of experimental measurements aimed at evaluating the zero point of the isotopes of plutonium in environmental samples by alfa spectrometry. After the International Moratorium in 1963, no release of plutonium has occurred in the environment apart from the burn up of SNAP 9A satellite in April 1964. Since then the plutonium concentration in air and in fallout samples has been continuously decreasing requiring, therefore, optimization of both instrumentation and experimental measurement procedures in order to obtain better sensibilities. In this work, the experimental methodology followed at the J.R.C.-Ispra for measurements of plutonium concentration in air, deposition and soil is described and the plutonium behaviour in these samples is reported and discussed starting from 1961.

  3. Measurements of plutonium in environmental samples

    International Nuclear Information System (INIS)

    D'Alberti, F.; Risposi, L.

    1996-01-01

    Within the activities connected with the start up of the PETRA Laboratory (Processo per l'Estrazione di Terre Rare ed Attinidi, i.e. process for extraction of rare earths and actinides), the Radiation Protection Unit of the J.R.C.-Ispra has carried out a well planned set of experimental measurements aimed at evaluating the zero point of the isotopes of plutonium in environmental samples by alfa spectrometry. After the International Moratorium in 1963, no release of plutonium has occurred in the environment apart from the burn up of SNAP 9A satellite in April 1964. Since then the plutonium concentration in air and in fallout samples has been continuously decreasing requiring, therefore, optimization of both instrumentation and experimental measurement procedures in order to obtain better sensibilities. In this work, the experimental methodology followed at the J.R.C.-Ispra for measurements of plutonium concentration in air, deposition and soil is described and the plutonium behaviour in these samples is reported and discussed starting from 1961

  4. The plutonium danger

    International Nuclear Information System (INIS)

    Ruiter, W. de

    1983-01-01

    Nobody can ignore the fact that plutonium is potentially very dangerous and the greatest danger concerning it lies in the spreading of nuclear weapons via nuclear energy programmes. The following seven different attitudes towards this problem are presented and discussed: 1) There is no connection between peaceful and military applications; 2) The problem cannot be prevented; 3) A technical solution must be found; 4) plutonium must be totally inaccessible to countries involved in acquiring nuclear weapons; 5) The use of plutonium for energy production should only occur in one multinational centre; 6) Dogmas in the nuclear industry must be enfeebled; 7) All developments in this area should stop. (C.F.)

  5. Automation of plutonium spectrophotometry

    International Nuclear Information System (INIS)

    Perez, J.J.; Boisde, G.; Goujon de Beauvivier, M.; Chevalier, G.; Isaac, M.

    1980-01-01

    Instrumentation was designed and constructed for automatic control of plutonium by molecular absorption spectrophotometry, on behalf of the reprocessing facilities, to meet two objectives: on-line measurement, of the valency state of plutonium, on by-pass, with the measured concentration covering the process concentration range up to a few mg.l -1 ; laboratory measurement of plutonium adjusted to valency VI, with operation carried out using a preparative system meeting the required containment specifications. For this two objectives, the photometer, optical cell connections are made by optical fibers resistant to β, γ radiation. Except this characteristic the devices are different according to the quality required for result [fr

  6. Plutonium Vulnerability Management Plan

    International Nuclear Information System (INIS)

    1995-03-01

    This Plutonium Vulnerability Management Plan describes the Department of Energy's response to the vulnerabilities identified in the Plutonium Working Group Report which are a result of the cessation of nuclear weapons production. The responses contained in this document are only part of an overall, coordinated approach designed to enable the Department to accelerate conversion of all nuclear materials, including plutonium, to forms suitable for safe, interim storage. The overall actions being taken are discussed in detail in the Department's Implementation Plan in response to the Defense Nuclear Facilities Safety Board (DNFSB) Recommendation 94-1. This is included as Attachment B

  7. Progress on plutonium stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Hurt, D. [Defense Nuclear Facilities Safety Board, Washington, DC (United States)

    1996-05-01

    The Defense Nuclear Facilities Safety Board has safety oversight responsibility for most of the facilities where unstable forms of plutonium are being processed and packaged for interim storage. The Board has issued recommendations on plutonium stabilization and has has a considerable influence on DOE`s stabilization schedules and priorities. The Board has not made any recommendations on long-term plutonium disposition, although it may get more involved in the future if DOE develops plans to use defense nuclear facilities for disposition activities.

  8. Cigarette smoke and plutonium

    International Nuclear Information System (INIS)

    Filipy, R.E.

    1982-01-01

    The major objective of this project is to obtain experimental data that are directly applicable to resolving the question of whether cigarette smokers are at greater risk than nonsmokers to potential health effects of inhaled plutonium. Progress was made on two fronts during the past year. The autoradiographic technique developed from detection of plutonium on the interior surface of pulmonary airways (Annual Report, 1978) has been adapted to routine use in examining tracheas and bronchi of rats. Also, dogs exposed to cigarette smoke for over a year after inhalation of plutonium were killed and necropsied

  9. Determination of oxidation products in radiolysis of halophenols with pulse radiolysis, hplc, and ion chromatography

    International Nuclear Information System (INIS)

    Ye, M.; Schuler, R.H.

    1990-01-01

    This paper reports on hydroxyl radicals that react with halogen substituted phenols by several different ways. One is addition of OH radicals to the aromatic ring, which is followed by elimination of hydrogen halide, H 2 O or H - . The positions of OH radicals attack are dependent on the nature of the halogen which affects the electronic distribution in the ring. The oxidation of fluorophenols, chlorophenols and bromophenols with hydroxyl radicals in N 2 O saturated solution has been investigated with pulse radiolysis and γ-irradiation experiments. The intermediates of the reactions were studied by pulse radiolysis. The products created in the γ-irradiation of aqueous solutions of halophenols were analyzed by ion chromatography and high performance liquid chromatography (HPLC). With the combination of time-resolved and steady-state experiments a complete and detailed description of radiolytic oxidation of halophenols by hydroxyl radicals was obtained

  10. Radiolysis of dilute aqueous solutions of cesium iodide

    International Nuclear Information System (INIS)

    Gorbovitskaya, T.I.; Galinkin, D.L.; Kants, L.K.; Tiliks, Yu.E.; Kotelkin, I.M.; Luzanova, L.M.

    1993-01-01

    Study of physical-chemical processes in the NPP containment by severe accident is carried out. Radiolysis of reactor cooling water containing iodine and cesium radionuclides penetrated therein in the course of accident is considered as of such processes. Role of ionizing radiation in the process of formation and release of ecologically hazardous volatile forms of radioiodine from reactor water into environment is studied. Experiments on radiolysis of CsI diluted water solutions are carried out. The data obtained were used for clarification of radiolysis mechanism for iodine-containing water system, enabling forecast of iodine behaviour in the course of the accident. 5 refs., 4 figs., 1 tab

  11. Radiolysis of phenol in aqueous solution at elevated temperatures

    International Nuclear Information System (INIS)

    Miyazaki, Toyoaki; Katsumura, Yosuke; Lin Mingzhang; Muroya, Yusa; Kudo, Hisaaki; Taguchi, Mitsumasa; Asano, Masaharu; Yoshida, Masaru

    2006-01-01

    γ-Radiolysis and pulse radiolysis of phenol in aqueous solution up to supercritical condition have been carried out. G-values of phenol consumption and product formation have been determined. While dihydroxybenzenes were major products at room temperature, multi-ring compounds and benzene were formed above 300 deg. C. This indicates reaction mechanism was changed above 300 deg. C, where phenoxyl radical plays a predominant role. This is supported by the observation of phenoxyl radical in pulse radiolysis. In supercritical water, the G-values increased with decrease of density

  12. Gamma-radiolysis of dimethyl sulfoxide. II. Radiolysis yields and possible mechanisms

    International Nuclear Information System (INIS)

    Gutierrez, M. C.; Barrera, R.

    1978-01-01

    As result of quantitative studies on gamma-radiolysis of DMSO at a dose range of 90-850 Mrads, constant G values have been obtained for the following radiolysis compounds: G(-DMSO) - 6.7 ±0.2; G(dimethyl sulphide) - 3.4 ±0.3; G(methane) - 0,75 ± 0.04; G(dimethyl disulphide) -0.33 ±0,03; G(tri methylsulphonium methanesulphonate) - 0.26 ± 0,01; G(methyl methanethiosulphonate) - 0,25 ±0.02; G(dimethyl sulphona)-0.21±0.02; G(H 2 )-0.18±0.02; and G(propane)--0.0092±0.0007. Initial G values have been obtained for other identified compounds: Gi(ethane)-0,46; Gi(CO)-0.052; and Gi(CO 2 )-0.030. Possible mechanisms on the radiolysis process are proposed. (Author) 17 refs

  13. Plutonium spectrophotometric analysis

    International Nuclear Information System (INIS)

    Esteban, A.; Cassaniti, P.; Orosco, E.H.

    1990-01-01

    Plutonium ions in solution have absorption spectra so different that it is possible to use them for analytical purposes. Detailed studies have been performed in nitric solutions. Some very convenient methods for the determination of plutonium and its oxidation states, especially the ratios Pu(III):Pu(IV) and Pu(IV):Pu(VI) in a mixture of both, have been developed. These methods are described in this paper, including: a) Absorption spectra for plutonium (III), (IV), (VI) and mixtures. b) Relative extinction coefficients for the above mentioned species. c) Dependences of the relative extinction coefficients on the nitric acid concentration and the plutonium VI deviation from the Beer-Lambert law. The developed methods are simple and rapid and then, suitable in process control. Accuracy is improved when relative absorbance measurements are performed or controlled the variables which have effect on the spectra and extinction coefficients. (Author) [es

  14. French plutonium management program

    International Nuclear Information System (INIS)

    Greneche, D.

    2002-01-01

    The French plutonium management program is summarized in this paper. The program considers nuclear generation as a major component of national electric power supply and includes the reprocessing of the spent fuel. (author)

  15. Learning more about plutonium

    International Nuclear Information System (INIS)

    2008-01-01

    This digest brochure explains what plutonium is, where it comes from, how it is used, its recycling into Mox fuel, its half life, historical discovery, its presence in the environment, toxicity and radioactivity. (J.S.)

  16. Plutonium safe handling

    International Nuclear Information System (INIS)

    Tvehlov, Yu.

    2000-01-01

    The abstract, prepared on the basis of materials of the IAEA new leadership on the plutonium safe handling and its storage (the publication no. 9 in the Safety Reports Series), aimed at presenting internationally acknowledged criteria on the radiation danger evaluation and summarizing the experience in the safe management of great quantities of plutonium, accumulated in the nuclear states, is presented. The data on the weapon-class and civil plutonium, the degree of its danger, the measures for provision of its safety, including the data on accident radiation consequences with the fission number 10 18 , are presented. The recommendations, making it possible to eliminate the super- criticality danger, as well as ignition and explosion, to maintain the tightness of the facility, aimed at excluding the radioactive contamination and the possibility of internal irradiation, to provide for the plutonium security, physical protection and to reduce irradiation are given [ru

  17. Recommended plutonium release fractions from postulated fires. Final report

    International Nuclear Information System (INIS)

    Kogan, V.; Schumacher, P.M.

    1993-12-01

    This report was written at the request of EG ampersand G Rocky Flats, Inc. in support of joint emergency planning for the Rocky Flats Plant (RFP) by EG ampersand G and the State of Colorado. The intent of the report is to provide the State of Colorado with an independent assessment of any respirable plutonium releases that might occur in the event of a severe fire at the plant. Fire releases of plutonium are of interest because they have been used by EG ampersand G to determine the RFP emergency planning zones. These zones are based on the maximum credible accident (MCA) described in the RFP Final Environmental Impact Statement (FEIS) of 1980, that MCA is assumed to be a large airplane crashing into a RFP plutonium building.The objective of this report was first, to perform a worldwide literature review of relevant release experiments from 1960 to the present and to summarize those findings, and second, to provide recommendations for application of the experimental data to fire release analyses at Rocky Flats. The latter step requires translation between experimental and expected RFP accident parameters, or ''scaling.'' The parameters of particular concern are: quantities of material, environmental parameters such as the intensity of a fire, and the physico-chemical forms of the plutonium. The latter include plutonium metal, bulk plutonium oxide powder, combustible and noncombustible wastes contaminated with plutonium oxide powder, and residues from plutonium extraction processes

  18. Determination of plutonium in pure plutonium nitrate solutions - Gravimetric method

    International Nuclear Information System (INIS)

    1987-01-01

    This International Standard specifies a precise and accurate gravimetric method for determining the concentration of plutonium in pure plutonium nitrate solutions and reference solutions, containing between 100 and 300 g of plutonium per litre, in a nitric acid medium. The weighed portion of the plutonium nitrate is treated with sulfuric acid and evaporated to dryness. The plutonium sulfate is decomposed and formed to oxide by heating in air. The oxide is ignited in air at 1200 to 1250 deg. C and weighed as stoichiometric plutonium dioxide, which is stable and non-hygroscopic

  19. Plutonium in coniferous forests

    International Nuclear Information System (INIS)

    Rantavaara, A.; Kostiainen, E.

    2002-01-01

    Our aim was to study the uptake of plutonium by trees, undervegetation and some wild foods. The ratio of 238 Pu/ 239,240 Pu in soil samples was determined for comparisons of the fallout origin. In twelve years the Chernobyl derived plutonium has not reached the mineral soil. This refers to a very slow downward migration in podsolic soil. The study confirmed also the low Pu uptake by vegetation and an insignificant contribution to human doses through wild foods. (au)

  20. Radiolysis of Ca14CO3

    International Nuclear Information System (INIS)

    Sanchez, M.G.A.

    1986-01-01

    The partition-ion exclusion chromatography is evaluated to analyse non-ionic organic compounds obtained from radiolysis of high specific activity Ca 14 CO 3 . The Ca 14 CO 3 was irradiated by β - decay of carbon-14 or by γ rays from a cobalt-60 source. The crystals were dissolved for qualitative and quantitative analysis of the radiolytic products. Formic and oxalic acids were produced in high yields. Glyoxylic, acetic and glycolic acids, formaldehyde and methanol were produced in low yields. Quantitative determination was carried out by liquid scintillation spectroscopy and the chemical yields (G-values) were calculated for the products. Mechanisms of product formation are proposed based on thermal annealing experiments. (Author) [pt

  1. Studies on radiolysis of amino acids, 1

    International Nuclear Information System (INIS)

    Oku, Tadatake

    1977-01-01

    In order to elucidate the radiolysis of amino acid, peptide, protein and enzyme, the radiolytic mechanisms of neutral amino acids (glycine, L-alanine, L-valine, L-leucine, L-isoleucine, L-serine, and L-threonine) and acidic amino acids (L-aspartic acid, L-glutamic acid and DL-amino-n-adipic acid) were studied in the presence of air or in the atmosphere nitrogen. An aqueous solution of 1 mM. of each amino acid was sealed in a glass ampoule under air or nitrogen. Irradiation of amino acid solutions was carried out with γ-rays of 60 Co at doses of 4.4-2,640x10 3 rads. The amino acids and the radiolytic products formed were determined by ion-exchange chromatography. From the results of determining amino acids and the radiolytic products formed and their G-values, the radiolytic mechanisms of the amino acids were discussed. (auth.)

  2. Pulse radiolysis of rhodamine dye solutions

    International Nuclear Information System (INIS)

    Kucherenko, E.A.; Kartasheva, L.I.; Pikaev, A.K.

    1982-01-01

    Applying the method of pulse radiolysis (5 MeV electrons) a study was made on intermediate products of rhodamine B radiolytic transformations in neutral aqueous and ethanol solutions. Rate constants of reactions of esub(aq) and OH with the dye (they are equal to (2.2+-0.3)x10 10 and (2.1+-0.3)x10 10 e/molxs, accordingly) as well as optical and kinetic characteristics of esub(aq), OH and H interaction products were measured. The nature of these products is concluded. It was found that in ethanol solutions the semirecovered form - electroneutral radical of rhodamine B - was the only intermediate product. It arises during the interaction of the dye with esub(s) (k=(9.2+-1.2)x10 9 e/molxs) and α-et hananol radical (k=(1.1+-0.1)x10 8 l/molxs). Properties of this product were investigated

  3. The pulse radiolysis of Decaborane-14 solutions

    International Nuclear Information System (INIS)

    Brown, B.J.; Sangster, D.F.

    1976-01-01

    Results for the pulse radiolysis of B 10 H 14 in selected solvent systems are reported. In polar solvents the solvated electron is rapidly scavenged by B 10 H 14 with k or approximately equal to 2 x 10 10 1. mol -1 s -1 . In H 2 O, CH 3 OH and C 2 H 5 OH a transient optical absorption (G x epsilon approximately 10 4 1. mol. -1 cm -1 ) attributed to boranyl radicals is observed. A lower yield is observed in aqueous acid and hydrocarbon solutions and in the presence of electron scavengers. The results are consistent with an electron scavenging reaction leading to formation of a boranyl radical. (author)

  4. Tritium release reduction and radiolysis gas formation

    Energy Technology Data Exchange (ETDEWEB)

    Batifol, G.; Douche, Ch.; Sejournant, Ch. [CEA Valduc, 21 - Is-sur-Tille (France)

    2008-07-15

    At CEA Valduc, the usual tritiated waste container is the steel drum. It allows good release reduction performance for middle activity waste but in some cases tritium outgassing from the waste drums is too high. It was decided to over-package each drum in a tighter container called the over-drum. According to good safety practices it was also decided to measure gas composition evolution into the over-drum in order to defect hydrogen formation over time. After a few months, a significant release reduction was observed. Additionally there followed contamination reduction in the roof storage building rainwater. However hydrogen was also observed in some over-drums, in addition to other radiolysis products. Catalyst will be added to manage the hydrogen risk in the over-drums. (authors)

  5. Subpicosecond pulse radiolysis studies on spur reactions and nanotechnology

    International Nuclear Information System (INIS)

    Tagawa, S.

    2003-01-01

    Recently we developed a subpicosecond pulse radiolysis system, although the time resolution of pulse radiolysis had remained about 30 ps for these 30 years. Time resolution and S/N ratio have been improved dramatically. The subpicosecond pulse radiolysis is a very powerful method to detect and observe transient phenomena in radiation chemistry and physics within 30 ps. By using the subpicosecond pulse radiolysis, many researches have been carried out on ultrafast phenomena in radiation chemistry, physics, biology and applied fields such as material science.Especially the spur reaction, which is one of the most important reactions in radiation chemistry, physics and biology, has been studied in the very wide time range from subpicosecond to several hundred nanoseconds by very high S/N ratio. These experimental results were analyzed theoretically and applied to the basic data for nanofabrication, which are very important in both next generation lithography and nanotechnology

  6. Radiolysis of Fricke solution: initial experiments with the pelletron facility

    International Nuclear Information System (INIS)

    Sharma, S.B.; Rao, B.S.M.

    1994-01-01

    Experimental details of heavy ion irradiation of aqueous solutions using the Nuclear Science Centre (NSC) pelletron facility and the initial results from the radiolysis of Fricke solution using oxygen-16 ions are reported. (author). 4 refs., 1 fig

  7. High Doses Gamma Radiolysis of PVC: Mechanisms of Degradation

    International Nuclear Information System (INIS)

    Colombani, J.

    2006-01-01

    PVC radiolysis leads to the formation of various degradation products: radicals, gas, oxidized products or polyenes. In order to predict the formation of the degradation products with regard to irradiation and ageing parameters, it is important to improve the understanding of the radiolysis mechanisms of PVC. Thus, we used several analytical techniques (Electron Spin Resonance, Fourier Transform Infrared spectroscopy, Nuclear Magnetic Resonance, Size Exclusion Chromatography) to get information on PVC samples irradiated at high doses (up to 4MGy) under different conditions. Gamma irradiation induces the formation of various radicals into PVC. Older studies were generally focused on the effect of low dose and/or low temperature irradiations on PVC. We present here ESR signals of PVC irradiated at high doses and at room temperature. We show that peroxyl radicals are producted by radiolysis under aerobe conditions and that polyenyl radicals are formed under anaerobe conditions. PVC radiolysis induces gas production and especially hydrogen chloride. Production of hydrogen chloride is well known until 1 MGy. We have studied by FTIR, the evolution of the quantity of HCl produced until 4 MGy. We show that higher irradiation dose leads to the lower radiolytic yield of HCl (G(HCl)). Moreover, G(HCl) obtained in aerobe conditions is about fourfold as great as G(HCl) observed in anaerobe radiolysis. Propagation and termination reactions induce degradation products: polyene sequences and crosslinking reactions are observed under anaerobe conditions; oxidized products with addition of chain scissions are formed under aerobe conditions. Although the literature about PVC radiolysis is rich, the main reacting pathways are not well established. Moreover the high doses studies are almost non-existent. We show by FTIR that aerobe radiolysis induces formation of ketons and acids. NMR experiments confirme these results but also focuse on small acids formed (with 2, 3 or 4 carbons). The

  8. Determination of plutonium in air and smear samples

    International Nuclear Information System (INIS)

    Hinton, E.R. Jr.; Tucker, W.O.

    1981-01-01

    A method has been developed for the determination of plutonium in air samples and smear samples that were collected on filter papers. The sample papers are digested in nitric acid, extracted into 2-thenoyltrifluoroacetone (TTA)-xylene, and evaporated onto stainless steel disks. Alpha spectrometry is employed to determine the activity of each plutonium isotope. Each sample is spiked with plutonium-236. All glassware used in the procedure is disposable. The detection limits are 3 and 5 dpm (disintegrations per minute) for air and smear samples, respectively, with an average recovery of 87%

  9. Determination of plutonium 241 in solutions of nuclear wastes

    International Nuclear Information System (INIS)

    Raymond, A.; Bilcot, J.B.; Poletiko, C.

    1990-09-01

    Determination of plutonium 241 in nuclear wastes is important because of long period and high energy of some daughter products. In this report are presented two quantitative analysis methods using both scintillation techniques: A complete method, in any case, by selective extraction of plutonium on an anionic resin allowing simultaneous determination of Pu 241 and the sum of other plutonium isotopes; a simplified method when alpha activity is higher than beta/gamma activity by liquid extraction with TTA. These methods are applied for analysis of 4 waste types: cement encapsulated wastes, bitumen encapsulated wastes, incineration ashes, leaching of encapsulated incineration ashes. In these 4 examples, Pu 241 activity is equal or higher than the sum of alpha plutonium isotope activity. Separation efficiency, measured from Pu 239 or with Pu 236 as tracer, is between 90 and 99% [fr

  10. γ-radiolysis of benzophenone in heptane solutions

    International Nuclear Information System (INIS)

    Melekhonova, I.I.; Romantsev, M.F.; Saraeva, V.V.

    1979-01-01

    The radiolysis mechanism of 8x10 -3 M solutions of benzophenon in heptane at 0 deg C and a dose of 3.8x10 20 eV/ml, is studied. The radiolysis products (benzpinacol and benzhydrol with alkyl substitution in aromatic ring) are isolated by the thin-layer chromatography. The identification of the products is performed using infrared and mass spectroscopy. The mechanism of the process is considered based on the reactions of a triplet state of benzophenon

  11. Radiolysis studies of uranyl nitrate solution in nitric acid medium

    International Nuclear Information System (INIS)

    Siri, Sandra; Mondino, Angel V.

    2005-01-01

    The radiolysis of acidic uranyl nitrate solutions was investigated using Co-60 gamma radiation. Hydrogen peroxide was determined as a function of increasing dose. The UV-vis absorption spectra of the irradiated solutions were measured and the spectral changes were analyzed. The increasing dose increases the absorbance intensities, possibly by an increment in nitrate concentration produced by radiolysis, which can originate the formation of different uranyl complexes in solution. (author)

  12. Simulation and control synthesis for a pulse column separation system for plutonium--uranium recovery

    International Nuclear Information System (INIS)

    McCutcheon, E.B.

    1975-05-01

    Control of a plutonium-uranium partitioning column was studied using a mathematical model developed to simulate the dynamic response and to test postulated separation mechanisms. The column is part of a plutonium recycle flowsheet developed for the recovery of plutonium and uranium from metallurgical scrap. In the first step of the process, decontamination from impurities is achieved by coextracting plutonium and uranium in their higher oxidation states. In the second step, reduction of the plutonium to a lower oxidation state allows partitioning of the plutonium and uranium. The use of hydroxylamine for the plutonium reduction in this partitioning column is a unique feature of the process. The extraction operations are carried out in pulse columns. (U.S.)

  13. Study on radiolysis products of N,N,N',N'-tetrabutyl-3-oxa-pentanediamide. Pt.1: Qualitative and quantitative analysis of dibutylamine

    International Nuclear Information System (INIS)

    Zhang Xiaolan; Shanghai Univ., Shanghai; Bao Borong; Shanghai Univ., Shanghai; Yang Yanqin; Ye Guoan; Zhang Xianye

    2005-01-01

    The study on radiolysis products of gamma-irradiated N,N,N',N'-tetrabutyl-3-oxa-pentane-diamide (TBOPDA) is very useful towards the extractant stability. IR and headspace solid-phase microextraction combined with gas chromatography/mass spectrometry (SPME-GC/MS) are used in the research. By comparisons with standard substances, dibutylamine and N,N-dibutylformamide are comfirmed to be the major radiolysis products. The influences of irradiation on TBOPDA and dibutylamine are quantitated by using headspace SPME-GC and HPLC. According to the experiment results, the possible ways of degradation are also proposed. (authors)

  14. Conversion of metal plutonium to plutonium dioxide by pyrochemical method

    Energy Technology Data Exchange (ETDEWEB)

    Panov, A.V.; Subbotin, V.G. [Russian Federal Nuclear Center, ALL-Russian Science and Research Institute of Technical Physics, Snezhinsk (Russian Federation); Mashirev, V.P. [ALL-Russian Science and Research Institute of Chemical Technology, Moscow (Russian Federation)

    2000-07-01

    Report contains experimental results on metal plutonium of weapon origin samples conversion to plutonium dioxide by pyrochemical method. Circuits of processes are described. Their advantages and shortcomings are shown. Parameters of plutonium dioxide powders (phase and fraction compositions, poured density) manufactured by pyrochemical method in RFNC-VNIITF are shown as well. (authors)

  15. Materials identification and surveillance project item evaluation: Items, impure plutonium oxide (ATL27960) and pure plutonium oxide (PEOR3258)

    International Nuclear Information System (INIS)

    Allen, T.; Appert, Q.; Davis, C.

    1997-03-01

    In this report, Los Alamos scientists characterize properties relevant to storage of an impure plutonium oxide (74 mass % plutonium) in accordance with the Department of Energy (DOE) standard DOE-STD-3013-96. This oxide is of interest because it is the first impure plutonium oxide sample to be evaluated and it is similar to other materials that must be stored. Methods used to characterize the oxide at certain points during calcination include surface-area analyses, mass loss-on-ignition (LOI) measurements, elemental analysis, moisture-adsorption measurements, and quantitative supercritical-CO 2 extraction of adsorbed water. Significant decreases in the LOI and surface area occurred as the oxide was calcined at progressively increasing temperatures. Studies indicate that supercritical-CO 2 extraction is an effective method for removing adsorbed water from oxides. We extracted the water from powdered oxides (high-purity ZrO 2 , pure PuO 2 , and impure plutonium oxide) using CO 2 at 3000 psi pressure and 75 degrees C, and we quantitatively determined it by using gravimetric and dew-point procedures. The effectiveness of the extraction method is demonstrated by good agreement between the amounts of water extracted from pure zirconium and plutonium dioxides and the mass changes obtained from LOI analyses. However, the amount of moisture (0.025 mass %) extracted from the impure plutonium oxide after it had been calcined at 950 degrees C and stored for a period of months is much less than the LOI value (0.97 mass %). These results imply that the impure plutonium oxide is free of adsorbed water after calcination at 950 degrees C, even though the sample does not satisfy the LOI requirement of <0.50 mass % for storage

  16. METHOD OF PRODUCING PLUTONIUM TETRAFLUORIDE

    Science.gov (United States)

    Tolley, W.B.; Smith, R.C.

    1959-12-15

    A process is presented for preparing plutonium tetrafluoride from plutonium(IV) oxalate. The oxalate is dried and decomposed at about 300 deg C to the dioxide, mixed with ammonium bifluoride, and the mixture is heated to between 50 and 150 deg C whereby ammonium plutonium fluoride is formed. The ammonium plutonium fluoride is then heated to about 300 deg C for volatilization of ammonium fluoride. Both heating steps are preferably carried out in an inert atmosphere.

  17. Chemical behaviour of plutonium in aqueous chloride solutions

    International Nuclear Information System (INIS)

    Bueppelmann, K.; Kim, J.I.

    1988-06-01

    The chemical behaviour of Plutonium has been investigated in concentrated NaCl solutions in the neutral pH range. The α-radiation induced radiolysis reactions oxidize the Cl - -ion to Cl 2 , HClO, ClO - and other species, which produce a strongly oxidizing medium. Under these conditions the Pu ions of lower oxidation states are readily oxidized to Pu(VI), which then undergo depending on the pH of the solution, various chemical reactions to produce PuO 2 Cl n , PuO 2 (ClO) m or PuO 2 (OH) x species. In addition to primary radiolysis reactions taking place in NaCl solutions, the reactions leading to the PuO 2 (Cl) n and PuO 2 (ClO) m species have been characterized and quantified systematically by spectroscopic and thermodynamic evaluation. The redox and complexation reactions of Pu ions under varying NaCl concentration, specific α-activity and pH are discussed. (orig.) [de

  18. Aqueous Solution Chemistry of Plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Clark, David L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-01-28

    Things I have learned working with plutonium: Chemistry of plutonium is complex; Redox equilibria make Pu solution chemistry particularly challenging in the absence of complexing ligands; Understanding this behavior is key to successful Pu chemistry experiments; There is no suitable chemical analog for plutonium.

  19. Physics of plutonium recycling

    International Nuclear Information System (INIS)

    2003-01-01

    The commercial recycling of plutonium as PuO 2 /UO 2 mixed-oxide (MOX) fuel is an established practice in pressurised water reactors (PWRs) in several countries, the main motivation being the consumption of plutonium arising from spent fuel reprocessing. Although the same motivating factors apply in the case of boiling water reactors (BWRs), they have lagged behind PWRs for various reasons, and MOX utilisation in BWRs has been implemented in only a few reactors to date. One of the reasons is that the nuclear design of BWR MOX assemblies (or bundles) is more complex than that of PWR assemblies. Recognizing the need and the timeliness to address this issue at the international level, the OECD/NEA Working Party on the Physics of Plutonium Fuels and Innovative Fuel Cycles (WPPR) conducted a physics code benchmark test for a BWR assembly. This volume reports on the benchmark results and conclusions that can be drawn from it. (authors)

  20. Preparation of fused chloride salts for use in pyrochemical plutonium recovery operations at Los Alamos

    International Nuclear Information System (INIS)

    Fife, K.W.; Bowersox, D.F.; Christensen, D.C.; Williams, J.D.

    1986-07-01

    The Plutonium Metal Technology Group at Los Alamos routinely uses pyrochemical processes to produce and purify plutonium from impure sources. The basic processes (metal production, metal purification, and residue treatment) involve controlling oxidation and reduction reactions between plutonium and its compounds in molten salts. Current production methods are described, as well as traditional approaches and recent developments in the preparation of solvent salts for electrorefining, molten salt extraction, lean metal (pyroredox) purification, and direct oxide reduction

  1. Preparation of fused chloride salts for use in pyrochemical plutonium recovery operations at Los Alamos

    Energy Technology Data Exchange (ETDEWEB)

    Fife, K.W.; Bowersox, D.F.; Christensen, D.C.; Williams, J.D.

    1986-07-01

    The Plutonium Metal Technology Group at Los Alamos routinely uses pyrochemical processes to produce and purify plutonium from impure sources. The basic processes (metal production, metal purification, and residue treatment) involve controlling oxidation and reduction reactions between plutonium and its compounds in molten salts. Current production methods are described, as well as traditional approaches and recent developments in the preparation of solvent salts for electrorefining, molten salt extraction, lean metal (pyroredox) purification, and direct oxide reduction.

  2. The uranium-plutonium breeder reactor fuel cycle

    International Nuclear Information System (INIS)

    Salmon, A.; Allardice, R.H.

    1979-01-01

    All power-producing systems have an associated fuel cycle covering the history of the fuel from its source to its eventual sink. Most, if not all, of the processes of extraction, preparation, generation, reprocessing, waste treatment and transportation are involved. With thermal nuclear reactors more than one fuel cycle is possible, however it is probable that the uranium-plutonium fuel cycle will become predominant; in this cycle the fuel is mined, usually enriched, fabricated, used and then reprocessed. The useful components of the fuel, the uranium and the plutonium, are then available for further use, the waste products are treated and disposed of safely. This particular thermal reactor fuel cycle is essential if the fast breeder reactor (FBR) using plutonium as its major fuel is to be used in a power-producing system, because it provides the necessary initial plutonium to get the system started. In this paper the authors only consider the FBR using plutonium as its major fuel, at present it is the type envisaged in all, current national plans for FBR power systems. The corresponding fuel cycle, the uranium-plutonium breeder reactor fuel cycle, is basically the same as the thermal reactor fuel cycle - the fuel is used and then reprocessed to separate the useful components from the waste products, the useful uranium and plutonium are used again and the waste disposed of safely. However the details of the cycle are significantly different from those of the thermal reactor cycle. (Auth.)

  3. Plutonium microstructures. Part 1

    International Nuclear Information System (INIS)

    Cramer, E.M.; Bergin, J.B.

    1981-09-01

    This report is the first of three parts in which Los Alamos and Lawrence Livermore National Laboratory metallographers exhibit a consolidated set of illustrations of inclusions that are seen in plutonium metal as a consequence of inherent and tramp impurities, alloy additions, and thermal or mechanical treatments. This part includes illustrations of nonmetallic and intermetallic inclusions characteristic of major impurity elements as an aid to identifying unknowns. It also describes historical aspects of the increased purity of laboratory plutonium samples, and it gives the composition of the etchant solutions and describes the etching procedure used in the preparation of each illustrated sample. 25 figures

  4. Potentiometric titration of plutonium

    International Nuclear Information System (INIS)

    Silver, G.L.

    1978-01-01

    In the potentiometric titration of plutonium(III), it has been customary to take the equivalence point as the inflection point on a plot of potential vs. volume of titrant. It have not been, however, demonstrated, that the stoichiometric end point corresponds to the inflection point. Suggestions are made according to which these points may not correspond in the potentiometric titration of plutonium(III), as these titrations are ordinarily concluded in a period of time which is short compared to the time required for valence state rearrangement through disproportionation. (T.G.)

  5. Precipitation of plutonium (III) oxalate and calcination to plutonium oxide

    International Nuclear Information System (INIS)

    Esteban, A.; Orosco, E.H.; Cassaniti, P.; Greco, L.; Adelfang, P.

    1989-01-01

    The plutonium based fuel fabrication requires the conversion of the plutonium nitrate solution from nuclear fuel reprocessing into pure PuO2. The conversion method based on the precipitation of plutonium (III) oxalate and subsequent calcination has been studied in detail. In this procedure, plutonium (III) oxalate is precipitated, at room temperature, by the slow addition of 1M oxalic acid to the feed solution, containing from 5-100 g/l of plutonium in 1M nitric acid. Before precipitation, the plutonium is adjusted to trivalent state by addition of 1M ascorbic acid in the presence of an oxidation inhibitor such as hydrazine. Finally, the precipitate is calcinated at 700 deg C to obtain PuO2. A flowsheet is proposed in this paper including: a) A study about the conditions to adjust the plutonium valence. b) Solubility data of plutonium (III) oxalate and measurements of plutonium losses to the filtrate and wash solution. c) Characterization of the obtained products. Plutonium (III) oxalate has several potential advantages over similar conversion processes. These include: 1) Formation of small particle sizes powder with good pellets fabrication characteristics. 2) The process is rather insensitive to most process variables, except nitric acid concentration. 3) Ambient temperature operations. 4) The losses of plutonium to the filtrate are less than in other conversion processes. (Author) [es

  6. Pulse radiolysis study on several fluoroquinolones

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Peng [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of Chinese Academy of Science, Beijing 100049 (China); Yao Side [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Li Haixia; Song Xiyu; Liu Yancheng [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Graduate University of Chinese Academy of Science, Beijing 100049 (China); Wang Wenfeng, E-mail: wangwenfeng@sinap.ac.c [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2011-04-15

    Reactions of several fluoroquinolones (FQs), including enoxacin, norfloxacin, and ciprofloxacin, with various reactive species such as e{sub aq}{sup -}, N{sup {center_dot}}{sub 3}, and {sup {center_dot}O}H are investigated by pulse radiolysis techniques. The FQ radical anions formed in the reactions of FQs with e{sub aq}{sup -} could either be protonated or deprotonated, and the absorption of FQ radical anions was located around 370 nm. The absorption of the neutral radicals produced in the protonation, and the radical dianions produced in the deprotonation of FQ radical anions were located in the 500-750 nm region. The FQ radical cations formed in the reactions of FQs with N{sub 3}{sup {center_dot}} showed an absorption band around 360 nm. Due to the strong bleaching below 350 nm, the absorption maxima ({lambda}{sub max}) of FQ radical anions, and the {lambda}{sub max} of FQ radical cations were not confirmed. The absorption of the FQ radical anions and cations was clearly pH dependent. Under neutral conditions, the reaction rate constants of FQs with e{sub aq}{sup -} and {sup {center_dot}O}H, which are diffusion controlled, were determined.

  7. Pulse radiolysis studies in model lipid systems

    International Nuclear Information System (INIS)

    Patterson, L.K.; Hasegawa, K.

    1978-01-01

    The kinetic and spectral behavior of radicals formed by hydroxyl radical attack on linoleate anions has been studied by pulse radiolysis. Reactivity of OH toward this surfactant is an order of magnitude greater in monomeric form (kOH + linoleate = 8.0 x 10 9 M -1 sec -1 ) than in mecellar form (kOH + lin(micelle) = 1.0 x 10 9 M -1 sec -1 ). Abstraction of a hydrogen atom from the doubly allylic position gives rise to an intense absorption in the UV region (lambda max = 282-286 nm, epsilon approximately 3 x 10 4 M -1 cm -1 ) which may be used as a probe of radical activity at that site. This abstraction may occur, to a small extent, directly via OH attack. However, greater than 90% of initial attack occurs at other sites. Subsequent secondary abstraction of doubly allylic H atoms appears to occur predominantly by: (1) intramolecular processes in monomers, (2) intermolecular processes in micelles. Disappearance of radicals by secondary processes is slower in the micellar pseudo phase than in monomeric solution. (orig.) 891 HK 892 KR [de

  8. Combinations of Aromatic and Aliphatic Radiolysis.

    Science.gov (United States)

    LaVerne, Jay A; Dowling-Medley, Jennifer

    2015-10-08

    The production of H(2) in the radiolysis of benzene, methylbenzene (toluene), ethylbenzene, butylbenzene, and hexylbenzene with γ-rays, 2-10 MeV protons, 5-20 MeV helium ions, and 10-30 MeV carbon ions is used as a probe of the overall radiation sensitivity and to determine the relative contributions of aromatic and aliphatic entities in mixed hydrocarbons. The addition of an aliphatic side chain with progressively from one to six carbon lengths to benzene increases the H(2) yield with γ-rays, but the yield seems to reach a plateau far below that found from a simple aliphatic such as cyclohexane. There is a large increase in H(2) with LET (linear energy transfer) for all of the substituted benzenes, which indicates that the main process for H(2) formation is a second-order process and dominated by the aromatic entity. The addition of a small amount of benzene to cyclohexane can lower the H(2) yield from the value expected from a simple mixture law. A 50:50% volume mixture of benzene-cyclohexane has essentially the same H(2) yield as cyclohexylbenzene at a wide variation in LET, suggesting that intermolecular energy transfer is as efficient as intramolecular energy transfer.

  9. Pulse radiolysis of bilirubin in aqueous solution

    International Nuclear Information System (INIS)

    Barber, D.J.W.; Richards, J.T.

    1977-01-01

    A pulse radiolysis study of bilirubin, the breakdown product of heme, has been made. In aqueous solution at pH 12, short-lived transient spectra have been obtained for reaction of bilirubin with e/sub aq//sup -/ and OH. Bimolecular rate constants for these reactions have been measured, namely, k/sub BR+e/sub aq//sup -/ equals 9.5 x 10 9 M -1 sec -1 and k/sub BR+OH/ equals 3.45 x 10 9 M -1 sec -1 , and the spectrum of a long-lived product resulting from decay of the bilirubin-OH adduct has been obtained. In addition, solute destruction by OH has been investigated in detail. The transient absorption spectrum for reduction of bilirubin with the H atom at neutral pH has been measured. By measuring the rate of reaction with e/sub aq//sup -/ in the presence of bovine serum albumin (BSA), the mode of binding of bilirubin to this biologically important compound has been studied

  10. Radiolysis of fluoro ethylene-propylene copolymer

    International Nuclear Information System (INIS)

    Hill, D.J.T.; Mohajerani, S.; Pomery, P.J.; Whittaker, A.K.

    1998-01-01

    Full text: Poly(tetrafluoroethylene-co-perfluoropropylene) (FEP), is used for medical and sophisticated aerospace applications. where a specialty polymer with high radiation-stability is required. Hence, an understanding of the radiation chemical processes is important and will lead to the design and development of the appropriate material for different applications. FEP like other fluoropolymers exhibits unique characteristics such as resistance to chemical attack by solvents, chemical inertness, thermal stability, excellent weathering resistance and outstanding electrical properties. Combination of theses properties together with a radiation stable polymer provides an excellent profile for a polymer appropriate for applications mentioned previously. The behavior of FEP upon irradiation depends on the environment and the temperature of the radiolysis. The mechanical and physical changes for un-irradiated as well as irradiated FEP have been studied using NMR, DMA, TGA and the mechanism of the crosslinking and degradation was studied using ESR. FEP has been known to degrade when irradiated at room temperature. However, there is evidence that irradiation of FEP in vacuum at temperatures above its glass transition temperature will result in crosslinking reactions predominating over chain scission or degradation. The FEP under study is a linear, semi-crystalline fluoroplastic with the glass transition temperature of 84-86 deg C. This fluoropolymer is commercially produced by copolymerisation of tetrafluoroethylene and perfluoropropylene

  11. A pulse radiolysis study of emulsion polymerization

    International Nuclear Information System (INIS)

    McAskill, N.A.

    1976-01-01

    The emulsion polymerisation of slightly water soluble monomers such as styrene occurs initially in micelles of surfactant swollen with monomer and later in larger particles consisting of polymer swollen with monomer and stabilized with an outer layer of surfactant. There is considerable controversy on whether the reaction sites of polymerization are inside or on the surface of the particle or micelle. The relative amounts of micelle and particles present at various stages of the polymerization are also nuclear. In the present study the OH radical formed by pulse radiolysis has been used as a probe to investigate the site of solubilization of styrene in various surfactant micelles. Two products can be distinguished by UV spectrometry, a benzyl type radical formed by OH addition to the side chain of styrene and a cyclohexadienyl type radical formed by addition to the ring. Wide differences in the relative amounts of each product were observed suggesting that in some surfactants the styrene ring is buried inside the micelle whilst in other systems the styrene appears to be so solubilized at the interface leaving both the ring and the side chain open to attack by the OH radical. (author)

  12. Current state of knowledge of water radiolysis effects on spent nuclear fuel corrosion

    International Nuclear Information System (INIS)

    Christensen, H.; Sunder, S.

    2000-07-01

    Literature data on the effect of water radiolysis products on spent-fuel oxidation and dissolution are reviewed. Effects of gamma radiolysis, alpha radiolysis, and dissolved O 2 or H 2 O 2 in unirradiated solutions are discussed separately. Also, the effect of carbonate in gamma-irradiated solutions and radiolysis effects on leaching of spent fuel are reviewed. In addition, a kinetic model for calculating the corrosion rates of UO 2 in solutions undergoing radiolysis is discussed. The model gives good agreement between calculated and measured corrosion rates in the case of gamma radiolysis and in unirradiated solutions containing dissolved oxygen or hydrogen peroxide. However, the model fails to predict the results of alpha radiolysis. In a recent study , it was shown that the model gave good agreement with measured corrosion rates of spent fuel exposed in deionized water. The applications of radiolysis studies for geologic disposal of used nuclear fuel are discussed. (author)

  13. Plutonium isotopes in the environment

    International Nuclear Information System (INIS)

    Holm, E.

    1977-12-01

    Determination of plutonium and americium by ion exchange and alpha-spectrometry. Deposition of global fall-out and accumulated area-content of 238 Pu, 239 Pu, 240 Pu, 241 Pu, 242 Pu and 241 Am in central Sweden (62.3 deg N, 12.4 deg E), by using the lichen species Cladonia alpestris as bioindicator. Retention and distribution of plutonium in carpets of lichen and soil. Transfer of plutonium from lichen to reindeer and man. Absorbed dose in reindeer and man from plutonium. Basic studies of plutonium and americium in the western Mediterranean surface waters, with emphases on particulate form of the transuranics. (author)

  14. Oxidation of ortho- and para-aminobenzoic acid. A pulse radiolysis- and gamma radiolysis study

    International Nuclear Information System (INIS)

    Solar, Sonja; Getoff, Nikola; Zona, Robert; Solar, Wolfgang

    2011-01-01

    The oxidation of anthranilic acid (ortho-aminobenzoic acid, ANA) and para-aminobenzoic acid (PABA) by · OH, N 3 · and O ·- in basic solution was studied by pulse radiolysis. The kinetic and spectroscopic characteristics of the intermediate transients were determined. For ANA the site attack of the OH radicals was established to be ∼50% on the -NH 2 moiety and ∼50% on the aromatic ring with an overall rate constant k( · OH+ANA)=(5.5x10 9 ) dm 3 mol -1 s -1 . The rate constant of PABA was k( · OH+PABA)=8x10 9 dm 3 mol -1 s -1 . The OH-adducts of both compounds showed a first order decay of 0.8x10 5 and 1.2x10 5 s -1 , respectively, whereby the corresponding anilino-radicals were formed. The rate constant of ANA with solvated electrons was k(e - aq +ANA)=2.9x10 9 dm 3 mol -1 s -1 . The radiation induced decomposition of both substrates was studied by gamma radiolysis as a function of the absorbed dose. They exhibited a distinct radiation resistance, the initial degradation yields were ∼0.16 μmol J -1 , i.e. only 28% of the · OH radicals contributed to their decomposition. The hydroxylation process was of minor importance, the yield of hydroxylated aminobenzoic acids was≤0.01 μmol J -1 .

  15. The radiolysis of CMPO: effects of acid, metal complexation and alpha vs. gamma radiation

    International Nuclear Information System (INIS)

    Mincher, B.J.; Groenewold, G.S.; Mezyk, S.P.

    2016-01-01

    The organophosphorus amide octyl(phenyl)-N,N-diisobutyl-carbamoylmethyl phosphine oxide (CMPO) is proposed for use in fuel cycle separations as a group actinide/lanthanide extractant. Alternative compounds such as the mono-amides and diglycol amides (DGAs) proposed for actinide and/or actinide/lanthanide extraction also contain the amidic functional group, but do not contain the CMPO aromatic or phosphoryl groups. Their radiation stability is in the order mono-amides > CMPO > DGA for irradiation under similar conditions. Although they produce similar radiolysis products, the kinetics of degradation for CMPO are completely different than for the other amides. CMPO degradation occurs in a zero-order fashion, and the -G-value for the change in [CMPO] is much lower when in the presence of acid. The DGAs and mono-amides degrade with pseudo-first-order kinetics and are not protected by acidity. Possible mechanistic reasons for the differences between CMPO and the other amides are discussed, as are the effects of the diluent and metal complexation on CMPO free radical reaction rates. Finally, it is also shown that α-irradiation has much less adverse effects on CMPO degradation than β/γ irradiation, both with respect to -G-values, and radiolysis product generation. (authors)

  16. The radiolysis of CMPO: effects of acid, metal complexation and alpha vs. gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Mincher, B.J.; Groenewold, G.S. [Idaho National Laboratory, PO Box 1625, Idaho Falls, ID 83415 (United States); Mezyk, S.P. [California State University at Long Beach, Long Beach, CA 90840 (United States)

    2016-07-01

    The organophosphorus amide octyl(phenyl)-N,N-diisobutyl-carbamoylmethyl phosphine oxide (CMPO) is proposed for use in fuel cycle separations as a group actinide/lanthanide extractant. Alternative compounds such as the mono-amides and diglycol amides (DGAs) proposed for actinide and/or actinide/lanthanide extraction also contain the amidic functional group, but do not contain the CMPO aromatic or phosphoryl groups. Their radiation stability is in the order mono-amides > CMPO > DGA for irradiation under similar conditions. Although they produce similar radiolysis products, the kinetics of degradation for CMPO are completely different than for the other amides. CMPO degradation occurs in a zero-order fashion, and the -G-value for the change in [CMPO] is much lower when in the presence of acid. The DGAs and mono-amides degrade with pseudo-first-order kinetics and are not protected by acidity. Possible mechanistic reasons for the differences between CMPO and the other amides are discussed, as are the effects of the diluent and metal complexation on CMPO free radical reaction rates. Finally, it is also shown that α-irradiation has much less adverse effects on CMPO degradation than β/γ irradiation, both with respect to -G-values, and radiolysis product generation. (authors)

  17. Investigation of plutonium (4) hydroxoformates

    International Nuclear Information System (INIS)

    Andryushin, V.G.; Belov, V.A.; Galaktionov, S.V.; Kozhevnikov, P.B.; Matyukha, V.A.; Shmidt, V.S.

    1982-01-01

    Deposition processes of plutonium (4) hydroxoformates in the system Pu(NO 3 ) 4 -HNO 3 -HCoOH-N6 4 OH-H 2 O have been studied in pH range 0.2-10.7 at total plutonium concentration in the system 100 g/l. It is shown that under the conditions plutonium (4) hydrolysis takes place with the formation of hydroxoformates. A local maximum of plutonium (4) hydroxoformate solubility in the range pH=3.8-4.8, which is evidently conditioned by the formation of soluble formate complex of plutonium in the region, is pointed out. The basic plutonium (4) formates of the composition PuOsub(x)(OH)sub(y)(COOH)sub(4-2x-y)xnHsub(2)O, where 1,3 >=x >= 0.7, 1.7 >= y >= 1.0 and n=1.5-7.0, are singled out, their thermal stability being studied. Density of the crystals and plutonium dioxide, formed during their thermal decomposition, is measured. It is established that for plutonium (4) hydroxoformates common regularities of the influence of salt composition (OH - -, CHOO - - and H 2 O-group numbers in the mulecule) on position of temperature decomposition effects and on the density of compounds, which have been previously found during the study of thorium and plutonium hydroxosalts are observed. It is shown that the density of plutonium dioxide decreases with the increase of hydration and hydrolysis degree of the initial plutonium hydroxoformate

  18. International plutonium policy

    International Nuclear Information System (INIS)

    1979-02-01

    As any other fissile material, the plutonium raises several utilization problems, particularly as far as diversion by sub-national groups or proliferation are concerned. The purpose of this paper is to show that these problems can be given reasonable solutions avoiding over penalties on energy production

  19. Plutonium safety training course

    International Nuclear Information System (INIS)

    Moe, H.J.

    1976-03-01

    This course seeks to achieve two objectives: to provide initial safety training for people just beginning work with plutonium, and to serve as a review and reference source for those already engaged in such work. Numerous references have been included to provide information sources for those wishing to pursue certain topics more fully. The first part of the course content deals with the general safety approach used in dealing with hazardous materials. Following is a discussion of the four properties of plutonium that lead to potential hazards: radioactivity, toxicity, nuclear properties, and spontaneous ignition. Next, the various hazards arising from these properties are treated. The relative hazards of both internal and external radiation sources are discussed, as well as the specific hazards when plutonium is the source. Similarly, the general hazards involved in a criticality, fire, or explosion are treated. Comments are made concerning the specific hazards when plutonium is involved. A brief summary comparison between the hazards of the transplutonium nuclides relative to 239 Pu follows. The final portion deals with control procedures with respect to contamination, internal and external exposure, nuclear safety, and fire protection. The philosophy and approach to emergency planning are also discussed

  20. Atomic spectrum of plutonium

    International Nuclear Information System (INIS)

    Blaise, J.; Fred, M.; Gutmacher, R.G.

    1984-08-01

    This report contains plutonium wavelengths, energy level classifications, and other spectroscopic data accumulated over the past twenty years at Laboratoire Aime Cotton (LAC) Argonne National Laboratory (ANL), and Lawrence Livermore National Laboratory (LLNL). The primary purpose was term analysis: deriving the energy levels in terms of quantum numbers and electron configurations, and evaluating the Slater-Condon and other parameters from the levels

  1. Plutonium: An introduction

    International Nuclear Information System (INIS)

    Condit, R.H.

    1993-10-01

    This report is a summary of the history and properties of plutonium. It presents information on the atoms, comparing chemical and nuclear properties. It looks at the history of the atom, including its discovery and production methods. It summarizes the metallurgy and chemistry of the element. It also describes means of detecting and measuring the presence and quantity of the element

  2. Plutonium Disposition by Immobilization

    International Nuclear Information System (INIS)

    Gould, T.; DiSabatino, A.; Mitchell, M.

    2000-01-01

    The ultimate goal of the Department of Energy (DOE) Immobilization Project is to develop, construct, and operate facilities that will immobilize between 17 to 50 tonnes (MT) of U.S. surplus weapons-usable plutonium materials in waste forms that meet the ''spent fuel'' standard and are acceptable for disposal in a geologic repository. Using the ceramic can-in-canister technology selected for immobilization, surplus plutonium materials will be chemically combined into ceramic forms which will be encapsulated within large canisters of high level waste (HLW) glass. Deployment of the immobilization capability should occur by 2008 and be completed within 10 years. In support of this goal, the DOE Office of Fissile Materials Disposition (MD) is conducting development and testing (D and T) activities at four DOE laboratories under the technical leadership of Lawrence Livermore National Laboratory (LLNL). The Savannah River Site has been selected as the site for the planned Plutonium Immobilization Plant (PIP). The D and T effort, now in its third year, will establish the technical bases for the design, construction, and operation of the U. S. capability to immobilize surplus plutonium in a suitable and cost-effective manner. Based on the D and T effort and on the development of a conceptual design of the PIP, automation is expected to play a key role in the design and operation of the Immobilization Plant. Automation and remote handling are needed to achieve required dose reduction and to enhance operational efficiency

  3. Plutonium cores of zenith

    Energy Technology Data Exchange (ETDEWEB)

    Barclay, F R; Cameron, I R; Drageset, A; Freemantle, R G; Wilson, D J

    1965-03-15

    The report describes a series of experiments carried out with plutonium fuel in the heated zero power reactor ZENITH, with the aim of testing current theoretical methods, with particular reference to excess reactivity, temperature coefficients, differential spectrum and reaction rate distributions. Two cores of widely different fissile/moderator atom ratios were loaded in order to test the theory under significantly varied spectrum conditions.

  4. Plutonium and textbooks

    International Nuclear Information System (INIS)

    Silver, G.L.

    2008-01-01

    Chemical equilibrium is not characterized by equilibrium constants alone. At least one conservation principle is necessary. Textbook descriptions of plutonium chemistry that are based on two-reaction-product disproportionation equations, or do not recognize the conservation principles, are incomplete and potentially misleading. (author)

  5. Japan's plutonium economy

    International Nuclear Information System (INIS)

    Hecht, M.M.

    1994-01-01

    Japan's plutonium economy is based on the most efficient use of nuclear energy, as envisioned under the Atoms for Peace program of the 1950s and 1960s. The nuclear pioneers assumed that all nations would want to take full advantage of atomic energy, recycling waste into new fuel to derive as much energy as possible from this resource

  6. Transport of plutonium nitrate

    International Nuclear Information System (INIS)

    1982-02-01

    This leaflet discusses the subject under the headings: why do we need plutonium; why must we transport it; what action is carried out; how is it moved; what are the risks. The transport of the material in specially designed containers, from Dounreay in Caithness by road and sea to Sellafield in Cumbria, is described. (U.K.)

  7. Heavy water radiolysis and chemistry control of the Fugen Nuclear Power Station

    International Nuclear Information System (INIS)

    Ibuki, Y.; Kitabata, T.; Kato, T.

    1989-01-01

    A computer analysis for heavy water radiolysis clarified the mechanism of the heavy water radiolysis rate change with impurities in the heavy water and cover gas, helium. The mechanism is supported by over ten years' operational data of the heavy water radiolysis in the Fugen nuclear power station. (author)

  8. Rapid Determination of Plutonium Isotopes in Environmental Samples Using Sequential Injection Extraction Chromatography and Detection by Inductively Coupled Plasma Mass Spectrometry

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2009-01-01

    This article presents an automated method for the rapid determination of 239Pu and 240Pu in various environmental samples. The analytical method involves the in-line separation of Pu isotopes using extraction chromatography (TEVA) implemented in a sequential injection (SI) network followed...... by detection of isolated analytes with inductively coupled plasma mass spectrometry (ICP-MS). The method has been devised for the determination of Pu isotopes at environmentally relevant concentrations, whereby it has been successfully applied to the analyses of large volumes/amounts of samples, for example......, 100−200 g of soil and sediment, 20 g of seaweed, and 200 L of seawater following analyte preconcentration. The investigation of the separation capability of the assembled SI system revealed that up to 200 g of soil or sediment can be treated using a column containing about 0.70 g of TEVA resin...

  9. The spectrographic analysis of plutonium oxide or mixed plutonium oxide/uranium oxide fuel pellets by the dried residue technique

    International Nuclear Information System (INIS)

    Jarbo, G.J.; Faught, P.; Hildebrandt, B.

    1980-05-01

    An emission spectrographic method for the quantitative determination of metallic impurities in plutonium oxide and mixed plutonium oxide/uranium oxide is described. The fuel is dissolved in nitric acid and the plutonium and/or uranium extracted with tributyl phosphate. A small aliquot of the aqueous residue is dried on a 'mini' pyrolitic graphite plate and excited by high voltage AC spark in an oxygen atmosphere. Spectra are recorded in a region which has been specially selected to record simultaneously lines of boron and cadmium in the 2nd order and all the other elements of interest in the 1st order. Indium is used as an internal standard. The excitation of very small quantities of the uraniumm/plutonium free residue by high voltage spark, together with three separate levels of containment reduce the hazards to personnel and the environment to a minimum with limited effect on sensitivity and accuracy of the results. (auth)

  10. Study of the radiolysis of water in porous media

    International Nuclear Information System (INIS)

    Rotureau, P.

    2004-01-01

    The understanding of the production of H 2 in the radiolysis of water confined into pores of concrete is important for the disposal of radioactive waste. In order to describe the mechanisms of water radiolysis in such heterogeneous porous systems we have studied the behaviour under gamma radiation of water confined in porous silica glasses with pores going from 8 to 300 nm of diameter and meso-porous molecular sieves (MCM-41). The radiolytic yields of hydroxyl radicals, hydrated electron and dihydrogen, have been determined with respect to the pore size of materials. The increase of these radiolytic yields compared to those of free water allowed us to show a charge transfer from silica to confined water. On the other hand the kinetics of hydrated electron reactions measured by pulse radiolysis are not modified. (author) [fr

  11. Radiolysis of water in the vicinity of passive surfaces

    International Nuclear Information System (INIS)

    Moreau, S.; Fenart, M.; Renault, J.P.

    2014-01-01

    Highlights: • HO° production through water radiolysis is enhanced near metal surfaces. • Hastelloy and Stainless steel surfaces can also produce HO° radicals through hydrogen peroxide activation. • There is a deficit in solvated electron production compared to hydroxyl radicals near metal surfaces. - Abstract: Porous metals were used to describe the water radiolysis in the vicinity of metal surfaces. The hydroxyl radical production under gamma irradiation was measured by benzoate scavenging in water confined in a 200 nm porous Ni base alloy or in Stainless steel. The presence of the metallic surfaces changed drastically the HO° production level and lifetime. The solvated electron production was measured via glycylglycine scavenging for Stainless steel and was found to be significantly smaller than hydroxyl production. These observations imply that interfacial radiolysis may deeply impact the corrosion behavior of the SS and Ni based alloys

  12. Breaking time-resolution limits in pulse radiolysis

    International Nuclear Information System (INIS)

    Yang Jinfeng; Kondoh, Takafumi; Norizawa, Kimihiro; Yoshida, Yoichi; Tagawa, Seiichi

    2009-01-01

    Pulse radiolysis, which is a time-resolved stroboscopic method based on ultrashort electron pulse and ultrashort analyzing light, is widely used for the study of the chemical kinetics and radiation primary processes or reactions. Although it has become possible to use femtosecond-pulse electron beam and femtosecond laser light in pulse radiolysis, the resolution is limited by the difference in group velocities of the electrons and the light in sample. In this contribution, we introduce a concept of equivalent velocity spectroscopy (EVS) into pulse radiolysis and demonstrate the methodology experimentally. In EVS, both the electron and the analyzing light pulses precisely overlap at every point in the sample and throughout the propagation time by rotating the electron pulse. The advance allows us to overcome the resolution degradation due to the different group velocity. We also present a method for measuring the rotated angle of the electron pulse and a technique for rotating the electron pulse with a deflecting cavity.

  13. A method for the separation of sodium and iron from plutonium and other impurities in concentrated plutonium solution and their subsequent measurement

    International Nuclear Information System (INIS)

    Mair, M.A.; Brown, M.L.

    1988-06-01

    Sodium and iron are separated from plutonium and other impurities by solvent extraction. Sodium is determined by flame photometry and iron by spectrophotometric measurement of the orthophenanthroline complex. (author)

  14. Use of plutonium for power production

    International Nuclear Information System (INIS)

    1965-01-01

    The panel reviewed available information on various aspects of plutonium utilization, such as physics of plutonium, technology of plutonium fuels in thermal and fast reactors, behaviour of plutonium fuel under reactor irradiation, technological and economic aspects of plutonium fuel cycle. Refs, figs and tabs

  15. Adsorption and diffusion of plutonium in soil

    International Nuclear Information System (INIS)

    Relyea, J.F.; Brown, D.A.

    1978-01-01

    The behavior of plutonium in soil--water systems was studied by measuring its apparent diffusion coefficient in the aqueous and solid phases and by finding the adsorption--desorption relationships between soil and solution. Apparent diffusion coefficients of plutonium in soil were measured using a quick-freeze method. Aqueous diffusion was studied in a capillary-tube diffusion cell. Adsorption studies were done by equilibrating a tagged soil--water mixture on a rotary shaker before centrifuging and sampling. As expected from high adsorption coefficients (Kd) (300--10,000), the apparent diffusion coefficients were low compared with normal soil cations (1.4 x 10 -8 cm 2 /sec in a sandy soil to less than 2.4 x 10 -11 cm 2 /sec in a silt loam). The Kd of plutonium in aqueous solution containing the chelate ethylenediaminetetraacetic acid (EDTA) was reduced compared with the Kd in dilute HNO 3 . As the EDTA concentration was increased, the Kd was decreased. The chelate diethylenetriaminepentaacetic acid (DTPA) reduced the Kd more than EDTA at comparable concentrations. The aqueous diffusion coefficients varied from 3.1 x 10 -7 cm 2 /sec in a solution extracted from the silt loam up to 2.7 x 10 -5 cm 2 /sec in a solution extracted from the sandy soil

  16. Reaction mechanisms in the radiolysis of peptides, polypeptides and proteins

    Energy Technology Data Exchange (ETDEWEB)

    Garrison, W.M.

    1985-01-01

    The purpose of this review is to bring together and to correlate the wide variety of experimental studies that provide information on the reaction products and reaction mechanisms involved in the radiolysis of peptides, polypeptides and proteins (including chromosomal proteins) in both aqueous and solid-state systems. The comparative radiation chemistry of these systems is developed in terms of specific reactions of the peptide main-chain and the aliphatic, aromatic-unsaturated and sulfur-containing side-chains. Information obtained with the various experimental techniques of product analysis, competition kinetics, spin-trapping, pulse radiolysis and ESR spectroscopy is included. 147 refs.

  17. Reaction mechanisms in the radiolysis of peptides, polypeptides and proteins

    International Nuclear Information System (INIS)

    Garrison, W.M.

    1985-01-01

    The purpose of this review is to bring together and to correlate the wide variety of experimental studies that provide information on the reaction products and reaction mechanisms involved in the radiolysis of peptides, polypeptides and proteins (including chromosomal proteins) in both aqueous and solid-state systems. The comparative radiation chemistry of these systems is developed in terms of specific reactions of the peptide main-chain and the aliphatic, aromatic-unsaturated and sulfur-containing side-chains. Information obtained with the various experimental techniques of product analysis, competition kinetics, spin-trapping, pulse radiolysis and ESR spectroscopy is included. 147 refs

  18. Formation and role of excited states in radiolysis - a foreword

    International Nuclear Information System (INIS)

    Singh, A.

    1976-01-01

    It is stated that the choice of contributions to the special issue of this Journal has been limited to those which bear on the details of the mechanisms of excited state formation and are likely to be useful to radiation chemists. Since more than half the energy deposited in radiolysis goes into excitation, studies on the fate of the excited species formed are very important. A brief reference is made to the subject matter of each of the fifteen contributions, and its significance to the development of the technique of radiolysis is outlined. (U.K.)

  19. Determination of low level of plutonium and uranium isotopes in safeguard swipe sample

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Myung Ho; Park, Jong Ho; Oh, Seong Yong; Lee, Chang Heon; Ahn, Hong Ju; Song, Kyu Seok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    For the determination of radionuclides, the separation techniques based on the principles of anion exchange, liquid-liquid extraction or column extraction chromatography are frequently used in nuclear analytical applications. Recently, a novel extraction chromatographic resin has been developed by Horwitz and co-workers, which are capable of selective extraction of the actinides. General separation of plutonium and uranium with extraction chromatographic techniques are focused on the environmental or radioactive waste samples. Also, the chemical yields for Pu and U isotopes with extraction chromatographic method sometimes are variable. For effective extraction of Pu isotopes in the very level of plutonium sample with UTEVA resin, the valence adjustment of Pu isotopes in the sample solution requires due to unstability in the oxidation state of Pu isotopes during separation step. Therefore, it is necessary to develop a simple and robust radiochemical separation method for nano- or pico gram amounts of uranium and plutonium in safeguard swipe samples. Chemical yields of plutonium and uranium with extraction chromatographic method of Pu and U upgrades in this study were compared with several separation methods for Pu and U generally used in the radiochemistry field. Also, the redox reactions of hydrogen peroxide with plutonium in the nitric acid media were investigated by UV-Vis-NIR absorption spectroscopy. Based on general extraction chromatography method with UTEVA resin, the separation method of nano- and picogram amounts of uranium and plutonium in safeguard swipe samples was developed in this study

  20. Plutonium Finishing Plant. Interim plutonium stabilization engineering study

    Energy Technology Data Exchange (ETDEWEB)

    Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J. [Pacific Northwest Lab., Richland, WA (United States); Nass, R. [Nuclear Fuel Services, Inc. (United States)

    1995-08-01

    This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage.

  1. Plutonium Finishing Plant. Interim plutonium stabilization engineering study

    International Nuclear Information System (INIS)

    Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J.; Nass, R.

    1995-08-01

    This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage

  2. Radiolysis of concentrated solutions. 2. Pulse and #betta#-radiolysis studies of direct and indirect effects in lithium iodide solutions

    International Nuclear Information System (INIS)

    Hadjadj, A.; Julien, R.; Pucheault, J.; Ferradini, C.; Hickel, B.

    1982-01-01

    In the preceding study of the radiolysis of concentrated aqueous LiCl solutions, one of the hypotheses used to explain the apparent inefficacy of Cl 2- formation by the direct effect was that molecular chlorine, not detectable by spectrophotometry, could be formed during the early stages of water radiolysis. Such an hypothesis is confirmed here for pulse and #betta#-radiolysis of concentrated aqueous neutral LiI solutions. Indeed, it is shown that, 10 ns after the pulse, molecular iodine, detected as I 3- , is formed with a yield that increases with the LiI concentration. The experimental results yields values of 4.8 and 7.3 respectively for the indirect and direct effects of total oxidation G/sub I 2- / + 2G/sub I 3- /. This last high value is discussed

  3. Flexible plutonium management with IFR technology

    International Nuclear Information System (INIS)

    Hannum, W.H.; Lineberry, M.J.

    1993-01-01

    From the earliest days of the development of peaceful nuclear power, it has been recognized that efficient utilization of nuclear fuel resources requires a closed fuel cycle (recycle). With a closed cycle, essentially all the energy content of mined uranium can be used, whereas a once-through light water reactor (LWR) cycle uses only ∼0.5%. Since weapons programs have used the PUREX process to extract plutonium, it has further been assumed that this is the appropriate technology for closing the uranium fuel cycle. In the United States, these assumptions were put into question by concerns over commerce in separated plutonium and the threat of diversion of this material for weapons use

  4. Automated spectrophotometer for plutonium and uranium determination

    International Nuclear Information System (INIS)

    Jackson, D.D.; Hodgkins, D.J.; Hollen, R.M.; Rein, J.E.

    1975-09-01

    The automated spectrophotometer described is the first in a planned series of automated instruments for determining plutonium and uranium in nuclear fuel cycle materials. It has a throughput rate of 5 min per sample and uses a highly specific method of analysis for these elements. The range of plutonium and uranium measured is 0.5 to 14 mg and 1 to 14 mg, respectively, in 0.5 ml or less of solution with an option to pre-evaporate larger volumes. The precision of the measurements is about 0.02 mg standard deviation over the range corresponding to about 2 rel percent at the 1-mg level and 0.2 rel percent at the 10-mg level. The method of analysis involves the extraction of tetrapropylammonium plutonyl and uranyl trinitrate complexes into 2-nitropropane and the measurement of the optical absorbances in the organic phase at unique peak wavelengths. Various aspects of the chemistry associated with the method are presented. The automated spectrophotometer features a turntable that rotates as many as 24 samples in tubes to a series of stations for the sequential chemical operations of reagent addition and phase mixing to effect extraction, and then to a station for the absorbance measurement. With this system, the complications of sample transfers and flow-through cells are avoided. The absorbance measurement system features highly stable interference filters and a microcomputer that controls the timing sequence and operation of the system components. Output is a paper tape printout of three numbers: a four-digit number proportional to the quantity of plutonium or uranium, a two-digit number that designates the position of the tube in the turntable, and a one-digit number that designates whether plutonium or uranium was determined. Details of the mechanical and electrical components of the instrument and of the hardware and software aspects of the computerized control system are provided

  5. Chemistry of plutonium revealed

    International Nuclear Information System (INIS)

    Connick, R.E.

    1992-01-01

    In 1941 one goal of the Manhattan Project was to unravel the chemistry of the synthetic element plutonium as rapidly as possible. In this paper the work carried out at Berkeley from the spring of 1942 to the summer of 1945 is described briefly. The aqueous chemistry of plutonium is quite remarkable. Important insights were obtained from tracer experiments, but the full complexity was not revealed until macroscopic amounts (milligrams) became available. Because processes for separation from fission products were based on aqueous solutions, such solution chemistry was emphasized, particularly precipitation and oxidation-reduction behavior. The latter turned out to be unusually intricate when it was discovered that two more oxidation states existed in aqueous solution than had previously been suspected. Further, an equilibrium was rapidly established among the four aqueous oxidation states, while at the same time any three were not in equilibrium. These and other observations made while doing a crash study of a previously unknown element are reported

  6. International plutonium policy

    International Nuclear Information System (INIS)

    1978-12-01

    The need to distinguish between diversion by sub-national groups and by governments is clearly stated. The paper identifies the international safeguards measures which already exist for the handling of plutonium. It proposes that the implementation of Article XII A5 of the IAEA statute concerning the international storage of plutonium could be an important additional measure. The paper also mentions the concept of using confinement as a complimentary safeguards measure and identifies the PIPEX concept. In addition, greater use is proposed of containment and surveillance procedures. The multiplication of small reprocessing plants spread over many countries is perceived as a proliferation risk. Other means such as co-location of reprocessing and fuel fabrication facilities are relevant to diversion by sub-national groups

  7. Current state of knowledge in radiolysis effects on spent fuel corrosion

    International Nuclear Information System (INIS)

    Christensen, H.; Sunder, S.

    1998-09-01

    Literature data on the effect of water radiolysis products on spent fuel oxidation and dissolution have been reviewed. Effects of γ-radiolysis, α-radiolysis and dissolved O 2 or H 2 O 2 in unirradiated solutions have been discussed separately. Also the effect of carbonate in γ-irradiated solutions and radiolysis effects on leaching of spent fuels have been reviewed. In addition a radiolysis model for calculation of corrosion rates of UO 2 , presented previously, has been discussed. The model has been shown to give a good agreement between calculated and measured corrosion rates in the case of γ-radiolysis and in unirradiated solutions of dissolved oxygen or hydrogen peroxide. The model has failed to predict the results of α-radiolysis. In a recent study it was shown that the model gave a good agreement with measured corrosion rates of spent fuel exposed in deionized water

  8. Strategies for the plutonium utilization

    International Nuclear Information System (INIS)

    Zouain, D.M.; Lima, J.O.V.; Sakamoto, L.H.

    1981-11-01

    A review of the activities involving plutonium (its recycle, utilization and technological status and perspectives) is done. These informations are useful for an economic viability study for the plutonium utilization in thermal reactors (recycling) and in fast breeders reactor (FBR), trying to collect the major number of informations about these subjects. The initial phase describes the present status and projections of plutonium accumulation and requirements. Then, the technological process are described and some strategies are analyzed. (E.G.) [pt

  9. Pulse radiolysis study of aqueous cyanamide solutions

    International Nuclear Information System (INIS)

    Draganic, I.G.; Draganic, Z.D.; Sehested, K.

    1978-01-01

    The radiolysis of oxygen-free, aqueous solutions of cyanamide was studied by fast kinetic spectrophotometry. Computer simulation of the reaction mechanisms was used to evaluate the experimental data. Four different species are identified: (1) the radical anion (NH 2 CN) - absorbing light in the UV with lambda/sub max/ 240 = 1500 M -1 cm -1 ; the disappearance is a second-order process with 2k = 1.3 x 10 9 M -1 s -1 ; (2) the hydrogen adduct, NH 2 C(H) double bond N (or NH 2 C double bond NH), with lambda/sub max/ 300 nm and epsilon 300 = 150 M -1 cm -1 decaying by second-order kinetics with 2k = 3.1 x 10 9 M -1 s -1 ; (3) the hydroxyl radical preferentially adds to the cyano group, NH 2 C(OH) double bond N (or NH 2 C double bond NOH). This species rearranges in the submicrosecond scale to NH 2 C ( double bond O) NH (lambda/sub max/ 325 nm and epsilon/sub 325 = 1900 M -1 cm -1 ) and disappears by a second-order process with 2k = 6.3 x 10 9 M -1 s -1 . (4) It is estimated that about 10% of OH radicals attack the substituent group and by H abstraction produce the NHCN radical (lambda/sub max/ 370 nm and epsilon 370 = 1800 M -1 cm -1 ); it disappears by a pseudo-first-order process attributed to a hydrolysis reaction. At increasing acidities, protonation of this radical takes place, NHCN + H + → + NH 2 CN; the protonated form decays faster and absorbs more strongly. In a cyanamide solution containing S 2 O 8 2- , the SO - 4 . radicals react with cyanamide, k = 1 x 10 8 M -1 s -1 , producing + NH 2 CN radicals. The dependence of the optical density at 325 nm on the dose rate and solute concentration are quantitatively consistent with the assumption that the OH radicals react with the NH 2 C(=O)NH species with k = 4 x 10 9 M -1 s -1

  10. Plutonium in the environment

    International Nuclear Information System (INIS)

    Kudo, A.

    2001-01-01

    The first volume of the new series, Radioactivity in the Environment, focuses on the environmental occurrence, the speciation, the behaviour, the fate, the applications and the health consequences of that much-feared and much-publicised element, plutonium. Featuring a collection of selected, peer-reviewed, up-to-date papers by leading researchers in the field, this work provides a state-of-the-art description of plutonium in the environment. This title helps to explain where present frontiers are drawn in our continuing efforts to understand the science of environmental plutonium and will help to place widespread concerns into perspective. As a whole this new book series on environmental radioactivity addresses, at academic research level, the key aspects of this socially important and complex interdisciplinary subject. Presented objectively and with the ultimate authority gained from the many contributions by the world's leading experts, the negative and positive consequences of having a radioactive world around us will be documented and given perspective. refs

  11. The effect of plutonium dioxide water surface coverage on the generation of hydrogen and oxygen

    Energy Technology Data Exchange (ETDEWEB)

    Veirs, Douglas K. [Los Alamos National Laboratory; Berg, John M. [Los Alamos National Laboratory; Crowder, Mark L. [Savannah River National Laboratory

    2012-06-20

    The conditions for the production of oxygen during radiolysis of water adsorbed onto plutonium dioxide powder are discussed. Studies in the literature investigating the radiolysis of water show that both oxygen and hydrogen can be generated from water adsorbed on high-purity plutonium dioxide powder. These studies indicate that there is a threshold in the amount of water below which oxygen is not generated. The threshold is associated with the number of monolayers of adsorbed water and is shown to occur at approximately two monolayers of molecularly adsorbed water. Material in equilibrium with 50% relative humidity (RH) will be at the threshold for oxygen generation. Using two monolayers of molecularly adsorbed water as the threshold for oxygen production, the total pressure under various conditions is calculated assuming stoichiometric production of hydrogen and oxygen. The specific surface area of the oxide has a strong effect on the final partial pressure. The specific surface areas resulting in the highest pressures within a 3013 container are evaluated. The potential for oxygen generation is mitigated by reduced relative humidity, and hence moisture adsorption, at the oxide surface which occurs if the oxide is warmer than the ambient air. The potential for oxygen generation approaches zero as the temperature difference between the ambient air and the material approaches 6 C.

  12. F. Biological hazards of plutonium

    International Nuclear Information System (INIS)

    1976-01-01

    Plutonium is an unavoidable result of present nuclear power programmes. Its predominant isotopes are extremely long-lived and very toxic if absorbed in the body. In view of the increasing potential for plutonium and man to come into contact, the consequences of any plutonium release into the environment should be scientifically examined. This report is an attempt to place in one document a fully referenced account of the on-going work in many areas. There are three sections. Part 1 deals with the amounts of plutonium available in the fuel cycle, its properties and the probability of routine or accidental release. Part 2 examines the ways in which plutonium can reach man, in particular through food chains or inhalation. Part 3 details the biological effects of plutonium once it is absorbed into the body, assesses the amounts likely to be harmful and discusses the adequacy of present standards for plutonium burdens. There are two appendices. The likely differences between Pu-239, the most studied isotope, and other plutonium isotopes or transuranic nuclides are outlined in Appendix A. Appendix B contains a fuller account of the ways in which the fate of ingested or inhaled plutonium have been determined

  13. Plutonium in the marine environment

    International Nuclear Information System (INIS)

    Jarvis, N.V.; Linder, P.W.; Wade, P.W.

    1994-01-01

    The shipping of plutonium from Europe to Japan around the Cape is a contentious issue which has raised public concern that South Africa may be at risk to plutonium exposure should an accident occur. The paper describes the containers in which the plutonium (in the form of plutonium oxide, PuO 2 ) is housed and consequences of the unlikely event of these becoming ruptured. Wind-borne pollution is considered not to be a likely scenario, with the plutonium oxide particles more likely to remain practically insoluble and sediment. Plutonium aqueous and environmental chemistry is briefly discussed. Some computer modelling whereby plutonium oxide is brought into contact with seawater has been performed and the results are presented. The impact on marine organisms is discussed in terms of studies performed at marine dump sites and after the crash of a bomber carrying nuclear warheads in Thule, Greenland in 1968. Various pathways from the sea to land are considered in the light of studies done at Sellafield, a reprocessing plant in the United Kingdom. Some recent debates in the popular scientific press, such as that on the leukemia cluster at Sellafield, are described. Plutonium biochemistry and toxicity are discussed as well as medical histories of workers exposed to plutonium. 35 refs., 2 tabs., 1 fig

  14. Pulse radiolysis of pyridine and methylpyridines in aqueous solutions

    DEFF Research Database (Denmark)

    Solar, S.; Getoff, N.; Sehested, K.

    1993-01-01

    The radicals formed from pyridine, 3-methylpyridine, 3,5-dimethylpyridine, 2,6-dimethylpyridine and 2,4,6-trimethylpyridine by attack of H, e(aq)-, OH and O.- in aqueous solutions were investigated by pulse radiolysis in the pH-range 1-13.8. The UV-vis. absorption spectra as well as the formation...

  15. Modelling the radiolysis of RSG-GAS primary cooling water

    Science.gov (United States)

    Butarbutar, S. L.; Kusumastuti, R.; Subekti, M.; Sunaryo, G. R.

    2018-02-01

    Water chemistry control for light water coolant reactor required a reliable understanding of radiolysis effect in mitigating corrosion and degradation of reactor structure material. It is known that oxidator products can promote the corrosion, cracking and hydrogen pickup both in the core and in the associated piping components of the reactor. The objective of this work is to provide the radiolysis model of RSG GAS cooling water and further more to predict the oxidator concentration which can lead to corrosion of reactor material. Direct observations or measurements of the chemistry in and around the high-flux core region of a nuclear reactor are difficult due to the extreme conditions of high temperature, pressure, and mixed radiation fields. For this reason, chemical models and computer simulations of the radiolysis of water under these conditions are an important route of investigation. FACSIMILE were used to calculate the concentration of O2 formed at relatively long-time by the pure water γ and neutron irradiation (pH=7) at temperature between 25 and 50 °C. This simulation method is based on a complex chemical reaction kinetic. In this present work, 300 MeV-proton were used to mimic γ-rays radiolysis and 2 MeV fast neutrons. Concentration of O2 were calculated at 10-6 - 106 s time scale.

  16. Pulse radiolysis study on aqueous solution of nicotine

    International Nuclear Information System (INIS)

    Wang Shilong; Mei Wang; Ni Yaming; Yao Side; Wang Wenfeng

    2004-01-01

    Nicotine has been studied for the first time by pulse radiolysis techniques. It has been found that hydrated electrons, hydrogen radicals and hydroxyl radicals can react with nicotine to produce anion radicals and neutral radicals, respectively, and the related rate constants have been determined. (authors)

  17. Gamma radiolysis of aqueous solution of ascorbic acid

    International Nuclear Information System (INIS)

    Loyola V, V.M.; Azamer B, J.A.; Laviada C, A.; Luna V, P.

    1977-01-01

    A preliminary study of the gamma radiolysis of a 1.13 x 10 -4 Maqueous solution of ascorbic acid is presented. It was found that dehydroascorbic acid was the principal product at doses of about 75 Krad. An increase in the dehydroascorbic acid concentration rangins from 5 to 40% was obtained, these values depend mainly on the initial ascorbic acid concentration. (author)

  18. The Plutonium Fuel Laboratory at Studsvik and Its Activities

    Energy Technology Data Exchange (ETDEWEB)

    Hultgren, A.; Berggren, G.; Brown, A.; Eng, H. U.; Forsyth, R. S. [AB Atomenergi, Studsvik (Sweden)

    1967-09-15

    The plutonium fuel laboratory at Studsvik is engaged in development work on plutonium-enriched fuel. At present, low enriched fuel for thermal reactors is being studied: work on fuel with a higher plutonium content for fast reactors is foreseen at a later date. So far only the pellet technique is under consideration, and a number of pellet rod specimens will be produced and irradiated in the reactor R2. These specimens include pellets from both co-precipitated uranium-plutonium salts and from physically mixed oxides. Comparison of these two materials will be extended to different density levels and different heat ratings. The methods and techniques used and studied include wet chemical work for powder preparation (continuous precipitation of Pu(IV)-oxalate with oxalic acid, continuous co-precipitation of plutonium and uranium with ammonia, optimization of.precipitation conditions using U(IV) and U(VI) respectively) ; powder preparation (drying, calcination, reduction, mixing, milling, binder addition, granulation); pellet preparation (pressing, debonding, sintering, inspection): encapsulation (charging, welding of end plug, helium filling, end sealing by welding, leak detection, decontamination); metallography (specimen preparation (moulding, polishing), etching, microscopy); structure investigations (thermal analysis (TG, DTA), X-ray diffraction, neutron diffraction, data handling by computer analysis); radiometric methods (direct plutonium determination by gamma spectrometry, non-destructive burn-up analysis by high resolution gamma spectrometry, using a Ge(Li) detector) ; rework of waste (recovery of plutonium from fuel waste by extraction with trilauryl amine and anion exchange). The plutonium fuel laboratory forms part of the Active Central Laboratory. The equipment is contained in four adjacent 10 x 15 m rooms; .for diffraction work and inactive uranium work additional space is available. All the forty glove boxes in operation except two are of AB Atomenergi

  19. Simulation study for purification, recovery of plutonium and uranium from plant streams of Fast Reactor Fuel Reprocessing Plant

    International Nuclear Information System (INIS)

    Sukumar, S.; Siva Kumar, P.; Radhika, R.; Subbuthai, S.; Mohan, S.V.; Subha Rao, R.V.

    2005-01-01

    A method for removal of plutonium from the lean organic streams obtained after co-stripping of uranium -plutonium was developed. Plutonium from lean organic phase was stripped using U 4+ /hydrazine as the stripping agent. The effect of concentrations of stripping agent U 4+ and feed Pu concentration in the lean organic phase was studied. Lean organic phases having higher plutonium concentration require three stages of stripping to bring plutonium concentration 4+ stabilized by hydrazine reduces Pu (IV) to Pu (III) thereby stripping plutonium from the organic phase. The non-extractability of Pu (III) by TBP was utilized for development of flow sheet for obtaining a uranium product lean of plutonium for ease of handling. (author)

  20. Reduction stripping of plutonium (IV) with hydroxylamine nitrate in the centrifugal contactor

    International Nuclear Information System (INIS)

    Zhang Zefu; Ding Dachun; Fei Hongcheng

    1989-01-01

    Reduction stripping of Pu(IV) with hydroxylamine nitrate under conditions of Purex 3B contactor is carried out with 16-stage mixer-centrifugal settler in laboratory scale. Results show that the apparent recovery of Pu is more than 99.9%. But there is a great difference in the concentration of plutonium of every stage in extraction equipment at different temperature. For example, plutonium concentrations in organic phase of several stages near the organic effluent at 45-50 deg C are lower than that at 20-24 deg C. Thus, recovery efficiency of plutonium can be assured only for the former. However, plutonium will probably be lost, if operating conditions are fluctuated. In addition, plutonium accumulated in the extraction equipment increased appreciably for the case of 20-24 deg C. Therefore, in order to ensure recovery efficiency of Pu, reduction stripping of Pu should be made at higher temperature

  1. A rapid method of dosing plutonium in radioactive effluents; Methode de dosage rapide du plutonium dans les effluents radioactifs (1961)

    Energy Technology Data Exchange (ETDEWEB)

    Scheidhauer, J; Messainguiral, L [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

    1961-07-01

    The plutonium is first separated by a lanthanum fluoride precipitation. The precipitated fluorides are dissolved in normal nitric acid solution in the presence of aluminium nitrate. The plutonium transformed to the tetravalent state is then extracted with thenoyltrifluoroacetone and returned to the aqueous phase with 10 N nitric acid. After evaporation on a watch glass the residue is calcined on a Meker burner and counted using a counting system fitted with a zinc sulphide scintillator. When necessary, the calcium is eliminated at the beginning of the dosage by a fluoride precipitation, the plutonium being oxidised to the valency IV. (authors) [French] Le plutonium est d'abord separe par entrainement au fluorure de lanthane. Le precipite des fluorures est remis en solution en milieu acide nitrique normal, en presence de nitrate d'aluminium. Le plutonium amene a la valence IV est alors extrait par la thenoyltrifluoroacetone et remis en phase aqueuse dans l'acide nitrique 10 N. Apres evaporation sur verre de montre, le residu est calcine sur bec Meker et compte sur un ensemble de comptage equipe d'un scintillateur au sulfure de zinc. Lorsque cela est necessaire, le calcium est elimine, au debut du dosage, par precipitation du fluorure, le plutonium etant oxyde a la valence VI. (auteurs)

  2. Plutonium oxides and uranium and plutonium mixed oxides. Carbon determination

    International Nuclear Information System (INIS)

    Anon.

    Determination of carbon in plutonium oxides and uranium plutonium mixed oxides, suitable for a carbon content between 20 to 3000 ppm. The sample is roasted in oxygen at 1200 0 C, the carbon dioxide produced by combustion is neutralized by barium hydroxide generated automatically by coulometry [fr

  3. The plutonium: brief presentation of its nuclear, physical and chemical properties

    International Nuclear Information System (INIS)

    Madic, C.

    1993-01-01

    In this text we give a brief presentation of the nuclear properties (isotopes, isotopic composition of spent fuels, decay), of the physical properties (phase diagrams, alloys) and of the chemical properties (complexes, solvent extraction) of the plutonium

  4. Recovery of americium-241 from aged plutonium metal

    International Nuclear Information System (INIS)

    Gray, L.W.; Burney, G.A.; Reilly, T.A.; Wilson, T.W.; McKibben, J.M.

    1980-12-01

    About 5 kg of ingrown 241 Am was recovered from 850 kg of aged plutonium using a process developed specifically for Savannah River Plant application. The aged plutonium metal was first dissolved in sulfamic acid. Sodium nitrite was added to oxidize the plutonium to Pu(IV) and the residual sulfamate ion was oxidized to nitrogen gas and sulfate. The plutonium and americium were separated by one cycle of solvent extraction. The recovered products were subsequently purified by cation exchange chromatography, precipitated as oxalates, and calcined to the oxides. Plutonium processng was routine. Before cation exchange purification, the aqueous americium solution from solvent extraction was concentrated and stripped of nitric acid. More than 98% of the 241 Am was then recovered from the cation exchange column where it was effectively decontaminated from all major impurities except nickel and chromium. This partially purified product solution was concentrated further by evaporation and then denitrated by reaction with formic acid. Individual batches of americium oxalate were then precipitated, filtered, washed, and calcined. About 98.5% of the americium was recovered. The final product purity averaged 98% 241 AmO 2 ; residual impurities were primarily lead and nickel

  5. High-temperature enthalpies of plutonium monocarbide and plutonium sesquicarbide

    International Nuclear Information System (INIS)

    Oetting, F.L.

    1979-01-01

    The high-temperature enthalpies of plutonium monocarbide and plutonium sesquicarbide have been determined with a copper-block calorimeter of the isoperibol type. The experimental enthalpy data, which was measured relative to 298 K, covered the temperature range from 400 to 1500 K. The calculation of the temperature rise of the calorimeter takes into account the added heat evolution from the radioactive decay of the plutonium samples. These enthalpy results, combined with the heat capacity and entropy of the respective carbide at 298 K available from the literature, has made it possible to generate tables of thermodynamic functions for the plutonium carbides. The behavior of the heat capacity of both of the plutonium carbides, i.e., a relatively steep increase in the heat capacity as the temperature increases, may be attributed to a premelting effect with the formation of vacancies within the crystal lattice although a theoretical treatment of this phenomenon is not given

  6. Plutonium separation by reduction stripping. Application to processing of mixed oxide (U,Pu)O2 fuel fabrication wastes

    International Nuclear Information System (INIS)

    Arnal, Thierry; Cousinou, Gerard; Ganivet, Michel.

    1978-11-01

    A procedure is described for separating plutonium from a uranium VI and plutonium IV mixture contained in an organic phase (tributyl phosphate diluted in dodecane). This separation is obtained by extracting the plutonium III using two organic reducers: hydrazine and paraminophenol. Paraminophenol has excellent reducing qualities, similar to those of ferrous sulphamate, but has the added advantage of not contaminating extracted plutonium. This procedure is currently used in processing production wastes from mixed oxide (U,Pu)O 2 fuels; the installation using this procedure is described in detail in this paper. Operating results show the remarkable efficiency of this procedure: the separated plutonium and uranium mass flows have been increased to 185 and 350 g.h -1 respectively; the uranium contains less than 0.1 ppm of plutonium on completion of the purification cycle [fr

  7. Removal of actinides from nuclear fuel reprocessing waste solutions with bidentate organophosphorus extractants

    International Nuclear Information System (INIS)

    Schulz, W.W.; McIsaac, L.D.

    1975-08-01

    The neutral bidentate organophosphorus reagents DBDECMP (dibutyl-N,N-diethylcarbamylmethylenephosphonate) and its dihexyl analogue DHDECMP are candidate extractants for removal of actinides from certain acidic waste streams produced at the U. S. ERDA Hanford and Idaho Falls sites. Various chemical and physical properties including availability, cost, purification, alpha radiolysis, and aqueous phase solubility of DBDECMP and DHDECMP are reviewed. A conceptual flowsheet employing a 15 percent DBDECMP (or DHDECMP)--CCl 4 extractant for removal (and recovery) of Am and Pu from Hanford's Plutonium Reclamation Facility acid waste stream (CAW solution) was successfully demonstrated in laboratory-scale mixer-settler tests; this extraction scheme can be used to produce an actinide-free waste. A 30 percent DBDECMP-xylene flowsheet is being tested at the Idaho Falls site for removal of U, Np, Pu, and Am from Idaho Chemical Processing Plant first-cycle high-level raffinate to produce an actinide-free (less than 10 nCi alpha activity/gram) waste. (auth)

  8. Some plutonium IV polymers properties in Purex process

    International Nuclear Information System (INIS)

    Scoazec, H.; Pasquiou, J.Y.; Germain, M.

    1990-01-01

    The metabolism of plutonium polymers in fuel reprocessing using the Purex process with tributylphosphate as solvent, and its practical consequence in real operation conditions are examined. Precipitation with dibutylphosphoric acid, a solvent degradation product, occurs both in extraction and stripping units when polymers are present. (author)

  9. Determination of plutonium in environment

    International Nuclear Information System (INIS)

    Sakanoue, Masanobu

    1978-01-01

    Past and present methods of determining the amount of plutonium in the environment are summarized. Determination of the amount of plutonium in uranium ore began in 1941. Plutonium present in polluted environments due to nuclear explosions, nuclear power stations, etc. was measured in soil and sand in Nagasaki in 1951 and in ash in Bikini in 1954. Analytical methods of measuring the least amount of plutonium in the environment were developed twenty years later. Many studies on and reviews of these methods have been reported all over the world, and a standard analytical procedure has been adopted. A basic analytical method of measurement was drafted in Japan in 1976. The yield, treatment of samples, dissolution, separation, control of measurable ray sources determination by α spectrometry, cross-check determination, and treatment of samples containing hardly soluble plutonium were examined. At present, the amount of plutonium can be determined by all of these methods. The presence of plutonium was studied further, and the usefulness of determination of the plutonium isotope ratio is discussed. (Kumagai, S.)

  10. Work surface for soluble plutonium

    International Nuclear Information System (INIS)

    Silver, G.L.

    2005-01-01

    A three-dimensional work surface for aqueous plutonium is illustrated. It is constructed by means of estimating work as a function of the ambient pH and redox potential in a plutonium solution. The surface is useful for illustrating the chemistry of disproportionation reactions. Work expressions are easier to use than work integrals. (author)

  11. The economics of plutonium recycle

    International Nuclear Information System (INIS)

    James, R.A.

    1977-11-01

    The individual cost components and the total fuel cycle costs for natural uranium and uranium-plutonium mixed oxide fuel cycles for CANDU-PHW reactors are discussed. A calculation is performed to establish the economic conditions under which plutonium recycle would be economically attractive. (auth)

  12. Plutonium Round Robin Test

    International Nuclear Information System (INIS)

    Dudder, G.B.; Herbillon, G.H.

    2001-01-01

    Full text: The goal of nuclear forensics is to develop a preferred approach to illicit trafficking investigations. This approach must be widely understood and acceptable as credible. The principle objectives of the Round Robin Test are to prioritize the forensic techniques and methods, evaluate attribution capabilities, and examine the utility of database. The Plutonium Round Robin has made a tremendous contribution to fulfilling these goals through a collaborative learning experience that resulted from the outstanding efforts of the six participating international laboratories. A prioritize list of techniques and methods has been developed based on this exercise. Future work will focus on a Highly Enriched Round Robin and extent to which the techniques and methods can be generalized. The Plutonium Round Robin demonstrated a rather high level of capability to determine the important characteristics of the materials and processes using analytical methods. When this capability to was combined with the appropriate knowledge and database, it resulted in a demonstrated capability to attribute the source of the materials to a specific nuclear fuel, reactor, and reprocessing facility. A number of shortfalls were also identified in our current capabilities. These included alternative dating techniques. Light Water Reactor discrimination techniques, and the lack of a comprehensive network of data/knowledge bases. The result of the Round Robin will be used to develop guidelines or a 'recommended protocol' to be made available to the interested authorities and countries to use in real cases. The poster will present a summary of the results of the Plutonium Round Robin and describe the plans the subsequent Highly Enriched Uranium Round Robin Test. (author)

  13. Solvent anode for plutonium purification

    International Nuclear Information System (INIS)

    Bowersox, D.F.; Fife, K.W.; Christensen, D.C.

    1986-01-01

    The purpose of this study is to develop a technique to allow complete oxidation of plutonium from the anode during plutonium electrorefining. This will eliminate the generation of a ''spent'' anode heel which requires further treatment for recovery. Our approach is to employ a solvent metal in the anode to provide a liquid anode pool throughout electrorefining. We use molten salts and metals in ceramic crucibles at 700 0 C. Our goal is to produce plutonium metal at 99.9% purity with oxidation and transfer of more than 98% of the impure plutonium feed metal from the anode into the salt and product phases. We have met these criteria in experiments on the 100 to 1000 g scale. We plan to scale our operations to 4 kg of feed plutonium and to optimize the process parameters

  14. Using Biomolecules to Separate Plutonium

    Science.gov (United States)

    Gogolski, Jarrod

    Used nuclear fuel has traditionally been treated through chemical separations of the radionuclides for recycle or disposal. This research considers a biological approach to such separations based on a series of complex and interdependent interactions that occur naturally in the human body with plutonium. These biological interactions are mediated by the proteins serum transferrin and the transferrin receptor. Transferrin to plutonium in vivo and can deposit plutonium into cells after interacting with the transferrin receptor protein at the cell surface. Using cerium as a non-radioactive surrogate for plutonium, it was found that cerium(IV) required multiple synergistic anions to bind in the N-lobe of the bilobal transferrin protein, creating a conformation of the cerium-loaded protein that would be unable to interact with the transferrin receptor protein to achieve a separation. The behavior of cerium binding to transferrin has contributed to understanding how plutonium(IV)-transferrin interacts in vivo and in biological separations.

  15. Cycle downstream: the plutonium question

    International Nuclear Information System (INIS)

    Zask, G.; Rome, M.; Delpech, M.

    1998-01-01

    This day, organized by the SFEN, took place at Paris the 4 june 1998. Nine papers were presented. They take stock on the plutonium physics and its utilization as a nuclear fuel. This day tried to bring information to answer the following questions: do people have to keep the plutonium in the UOX fuel or in the MOX fuel in order to use it for future fast reactors? Do people have to continue obstinately the plutonium reprocessing in the MOX for the PWR type reactors? Will it be realized a underground disposal? Can it be technically developed plutonium incinerators and is it economically interesting? The plutonium physics, the experimental programs and the possible solutions are presented. (A.L.B.)

  16. Plutonium storage study

    International Nuclear Information System (INIS)

    1979-01-01

    This Spanish study gives a more detailed analysis of a possible store for plutonium oxide. The capacity of the store is assumed to be 30 t Pu and the minimum storage time 2 years. The study includes a general description of the store and its design philosophy; comments on the quality and properties of the material stored; a detailed criticality study and comments on gas and heat generation and shielding requirements; and a brief cost evaluation. Costs are estimated to be about $110/kg PuO 2 /year

  17. The radiolysis of uracil in oxygenated aqueous solutions. A study by product analysis and pulse radiolysis

    International Nuclear Information System (INIS)

    Schuchnmann, M.N.; Sonntag, C. von

    1983-01-01

    Hydroxyl radicals are generated by the radiolysis of N 2 O-O 2 (4:1 v/v)-saturated aqueous solutions of uracil. They add to the 5,6-double bond of the substrate. These radicals are converted by oxygen into the corresponding peroxyl radicals (I) and (II), respectively. Peroxyl radical (I) undergoes a base-induced O 2 - elimination. As an intermediate 5-hydroxyisopyrimidine is formed which rearranges into isobarbituric acid and adds water forming 5,6-dihydro-5,6-dihydroxyuracil. Competing with this base-induced reaction of radical (I) there is a bimolecular decay of radicals (I) and (II). These processes become predominant at low pH. For this reason a strong pH dependence of G (products) is observed. The major products are (G values at pH 3 and 10 in parentheses) 5,6-dihydroxy-5,6-dihydrouracil (1.1; 2.4), isobarbituric acid (0; 1.2), N-formyl-5-hydroxyhydantoin (1.6; 0.2), 5-hydroxybarbituric acid (0.9; 0.2). 5-Hydroxybarbituric acid is formed in its keto form. Its deprotonation has been followed by pulse conductometry. Details of the reaction mechanism, e.g. the involvement of oxyl radicals in the bimolecular decay of (I) and (II), are discussed. (author)

  18. Geochemical association of plutonium in marine sediments from Palomares (Spain)

    International Nuclear Information System (INIS)

    Anton, M.P.; Gasco, C.; Sanchez-Cabeza, J.A.; Pujol, L.

    1994-01-01

    The geochemical association of plutonium in sediments from the marine ecosystem of Palomares has been studied. A sequential leaching technique using selective extractants has been employed to determine the percentages of Pu in the following forms: (a) readily available, (b) exchangeable and adsorbed to specific sites, (c) associated with organic matter, (d) sesquioxides, (e) residual. Plutonium was found to be associated mainly with phases (c), (d) and (e), and therefore, appears to be relatively immobile and not readily available to bottom feeding biota. The effect of different source terms on Pu distribution is also discussed. (orig.)

  19. The toxicity of plutonium

    International Nuclear Information System (INIS)

    Ramsden, D.; Johns, T.F.

    1977-01-01

    Reference is made to recent publications concerned with the radiotoxicity of inhaled insoluble Pu compounds. The publications are a paper by Thorne and Vennart (Nature 263:555 (1976)), a report entitled 'The Toxicity of Plutonium', (London (HMSO), 1975), and the 'Sixth Report of the Royal Commission on Environmental Pollution', (Cmnd. 6618, London (HMSO), 1976). Thorne and Vennart concluded that the previously accepted value for the maximum permissible annual intake (MPAI) of such compounds may be too high by a factor of about five, and a similar conclusion was reached in the other two publications. It is thought by the present authors that the methods which have been used to suggest new values for the MPAI are unduly pessimistic for high-fired PuO 2 ; calculations have been based on the lung model of ICRP Publication 19 'The Metabolism of Compounds of Plutonium and the Other Actinides', (International Commission of Radiological Protection, 1972). This involves concluding that the risks to bone and liver are comparable to those for lung. This is discussed and it is thought that the previously established idea that the lung is the critical organ remains substantially correct for the case of high-fired PuO 2 . (U.K.)

  20. Plutonium oxide dissolution

    International Nuclear Information System (INIS)

    Gray, J.H.

    1992-01-01

    Several processing options for dissolving plutonium oxide (PuO 2 ) from high-fired materials have been studied. The scoping studies performed on these options were focused on PuO 2 typically generated by burning plutonium metal and PuO 2 produced during incineration of alpha contaminated waste. At least two processing options remain applicable for dissolving high-fired PuO 2 in canyon dissolvers. The options involve solid solution formation of PuO 2 With uranium oxide (UO 2 ) and alloying incinerator ash with aluminum. An oxidative dissolution process involving nitric acid solutions containing a strong oxidizing agent, such as cerium (IV), was neither proven nor rejected. This uncertainty was due to difficulty in regenerating cerium (IV) ions during dissolution. However, recent work on silver-catalyzed dissolution of PuO 2 with persulfate has demonstrated that persulfate ions regenerate silver (II). Use of persulfate to regenerate cerium (IV) or bismuth (V) ions during dissolution of PuO 2 materials may warrant further study

  1. Separation Techniques for Uranium and Plutonium at Trace Levels for the Thermal Ionization Mass Spectrometric Determination

    International Nuclear Information System (INIS)

    Suh, M. Y.; Han, S. H.; Kim, J. G.; Park, Y. J.; Kim, W. H.

    2005-12-01

    This report describes the state of the art and the progress of the chemical separation and purification techniques required for the thermal ionization mass spectrometric determination of uranium and plutonium in environmental samples at trace or ultratrace levels. Various techniques, such as precipitation, solvent extraction, extraction chromatography, and ion exchange chromatography, for separation of uranium and plutonium were evaluated. Sample preparation methods and dissolution techniques for environmental samples were also discussed. Especially, both extraction chromatographic and anion exchange chromatographic procedures for uranium and plutonium in environmental samples, such as soil, sediment, plant, seawater, urine, and bone ash were reviewed in detail in order to propose some suitable methods for the separation and purification of uranium and plutonium from the safeguards environmental or swipe samples. A survey of the IAEA strengthened safeguards system, the clean room facility of IAEA's NWAL(Network of Analytical Laboratories), and the analytical techniques for safeguards environmental samples was also discussed here

  2. Separation Techniques for Uranium and Plutonium at Trace Levels for the Thermal Ionization Mass Spectrometric Determination

    Energy Technology Data Exchange (ETDEWEB)

    Suh, M. Y.; Han, S. H.; Kim, J. G.; Park, Y. J.; Kim, W. H

    2005-12-15

    This report describes the state of the art and the progress of the chemical separation and purification techniques required for the thermal ionization mass spectrometric determination of uranium and plutonium in environmental samples at trace or ultratrace levels. Various techniques, such as precipitation, solvent extraction, extraction chromatography, and ion exchange chromatography, for separation of uranium and plutonium were evaluated. Sample preparation methods and dissolution techniques for environmental samples were also discussed. Especially, both extraction chromatographic and anion exchange chromatographic procedures for uranium and plutonium in environmental samples, such as soil, sediment, plant, seawater, urine, and bone ash were reviewed in detail in order to propose some suitable methods for the separation and purification of uranium and plutonium from the safeguards environmental or swipe samples. A survey of the IAEA strengthened safeguards system, the clean room facility of IAEA's NWAL(Network of Analytical Laboratories), and the analytical techniques for safeguards environmental samples was also discussed here.

  3. The effect of dissolved oxygen on water radiolysis behaviour

    International Nuclear Information System (INIS)

    Yakabuskie, P.A.; Joseph, J.M.; Wren, J.C.; Stuart, C.R.

    2012-09-01

    A quantitative understanding of the chemical or redox environments generated in water by ionizing radiation is important for material selection, development of maintenance programs, and safety assessments for water-cooled nuclear power reactors. The highly reactive radicals (·OH, ·H, ·e aq - , ·HO 2 , and ·O 2 - ) and molecular species (H 2 and H 2 O 2 ) generated by water radiolysis can compete in reactions with other dissolved compounds and impose changes to the system chemistry by altering the steady-state concentrations of water radiolysis products, which could impact the degradation of materials in contact with the aqueous phase. Understanding in detail how a given chemical additive changes the long-term radiolysis kinetics can help us to determine what chemistry control steps may be required to return the system to an optimal redox condition, and in turn, enhance the lifetime of reactor components. This study outlines the effect of dissolved oxygen gas, which could be introduced due to air ingress, on long-term water radiolysis behaviour. The effects of solution pH and initial dissolved O 2 concentration on the radiolytic production of molecular H 2 and H 2 O 2 have been investigated by performing experiments with three different O 2 concentrations at pH 6.0 and 10.6 under steady-state radiolysis conditions. The aqueous and gas phase analyses were performed using UV-Vis spectrophotometry and gas-chromatography equipped with electron capture and thermal conductivity detectors. The experimental results were compared with kinetic model calculations of steady-state radiolysis and were found to be in good agreement. The concentrations of water radiolysis products, H 2 O 2 and H 2 , were found to increase in the presence of dissolved oxygen, but the degree of increase was shown to depend on the solution pH. Furthermore, the steady-state concentration of H 2 did not increase as greatly as that of H 2 O 2 at either pH studied. The kinetic analyses have shown

  4. Radiolysis of actinides and technetium in alkaline media

    Energy Technology Data Exchange (ETDEWEB)

    Delegard, C.H., Westinghouse Hanford

    1996-07-10

    The {gamma}-radiolysis of aerated alkaline aqueous solutions of Np(V), Np(VI), Pu(VI), Tc(IV), Tc(V), and TC(VII) was studied in the absence of additives and in the presence of CO{sub 3}{sup 2-}, NO{sub 3}{sup -}, NO{sub 2}{sup -}, EDTA, formate, and other organic compounds. The radiolytic reduction of Np(V), Np(VI), Pu(VI), and TC(VII) under different experimental conditions was examined in detail. The addition of EDTA, formate, and alcohols was found to considerably increase the radiation-chemical reduction yields. The formation of the Np(V) peroxo complex was observed in the {gamma}-radiolysis of alkaline aqueous solutions of Np (VI) in the presence of nitrate.

  5. Simultaneous action of external irradiation and products of air radiolysis

    International Nuclear Information System (INIS)

    Golikov, V.Ya.; Karklinskaya, O.N.; Mikhalev, V.P.; Vorotyntsev, A.P.; Kotov, N.N.

    1977-01-01

    To study the radiation damage due to the simultaneous effect of the acute ionizing radiation on the organism and the products of air radiolysis-ozone and nitrogen oxides, laboratory experiments were made. The scheme of the irradiation was the following: the acute dynamic effect (per hour) of X-rays at different doses, and nitrogen oxides and ozone with different concentrations. Male mice were exposed to irradiation (dose of 50-1000 rad, for 60 min.). Data obtained (mortality, survival, exponents of the peripheral blood) proved the radioprotective ability of the chemical agents under study. The radioprotective action was most pronounced at high concentrations. The fact proves that the mechanism of the simultaneous action of the products of air radiolysis and X-ray radiation is complex, and further efforts should be made at its investigation

  6. Study of polysilane mainchain electronic structure by picosecond pulse radiolysis

    International Nuclear Information System (INIS)

    Habara, H.; Saeki, A.; Kunimi, Y.; Seki, S.; Kozawa, T.; Yoshida, Y.; Tagawa, S.

    2000-01-01

    The electronic structure of a charged polysilane molecle is studied. The transient absorption spectroscopy was carried out for charged radicals of poly (methylphenylsilane): PMPS by pico-second and nanosecond pulse radiolysis technique. It was observed that the peak of the transient absorption spectra shifted to longer wavelength region within a few nsec, and an increase was observed in the optical density at 370 nm, which had been already assigned to the radical anions of PMPS. It is ascribed to inter-segment electron transfer (intra-molecular transfer) through polymer chain. The nanosecond pulse radiolysis experiments gave similar kinetic traces in near-UV and IR region. This suggests the presence of an interband level, that is, a polaron level occupied by an excess electron or a hole. (author)

  7. EXTRACT

    DEFF Research Database (Denmark)

    Pafilis, Evangelos; Buttigieg, Pier Luigi; Ferrell, Barbra

    2016-01-01

    The microbial and molecular ecology research communities have made substantial progress on developing standards for annotating samples with environment metadata. However, sample manual annotation is a highly labor intensive process and requires familiarity with the terminologies used. We have the...... and text-mining-assisted curation revealed that EXTRACT speeds up annotation by 15-25% and helps curators to detect terms that would otherwise have been missed.Database URL: https://extract.hcmr.gr/......., organism, tissue and disease terms. The evaluators in the BioCreative V Interactive Annotation Task found the system to be intuitive, useful, well documented and sufficiently accurate to be helpful in spotting relevant text passages and extracting organism and environment terms. Comparison of fully manual...

  8. Plutonium isotopic determination from gamma-ray spectra

    International Nuclear Information System (INIS)

    Skourikhine, A.N.; Strittmatter, R.B.; Zardecki, A.

    1998-01-01

    The use of low- and medium-resolution room-temperature detectors for the nondestructive assay of nuclear materials has widespread applications to the safeguarding of nuclear materials. The challenge to using these detectors is the inherent difficulty of the spectral analysis to determine the amount of specific nuclear materials in the measured samples. This is especially true for extracting plutonium isotopic content from low- and medium-resolution spectral lines that are not well resolved. In this paper, neural networks trained by stochastic and singular value decomposition algorithms are applied to retrieve the plutonium isotopic content from a simulated NaI spectra. The simulated sample consists of isotopes 238 Pu, 239 Pu, 240 Pu, 241 Pu, 242 Pu, and 241 Am. It is demonstrated that the neutral network optimized by singular value decomposition (SVD) and stochastic training algorithms is capable of estimating plutonium content consistently resulting in an average error much smaller than the error previously reported

  9. Pulse Radiolysis of Adrenaline in Acid Aqueous Solutions

    DEFF Research Database (Denmark)

    Gohn, M.; Getoff, N.; Bjergbakke, Erling

    1976-01-01

    Pulse radiolysis of adrenaline in acid aqueous solutions (pH 1–3) was carried out. The rate constants for the reactions of adrenaline with H and OH were determined: k(H + adr.) = (0·9±0·1) × 109 dm3 mol−1s−1; k(OH + adr.) = (1·65±0·15) × 1010 dm3 mol−1s−1. The H-adduct of adrenaline has two λmax...

  10. γ-Irradiation-induced radiolysis of inulin in aqueous solutions

    International Nuclear Information System (INIS)

    Tsyba, I.A.; Revina, A.A.; Shostenko, A.G.

    1997-01-01

    Radiochemical transformations of inulin in aqueous solutions, in air, in the presence of inert gases, helium, nitrogen and in nitrous oxide exposed to various doses of 60 Co γ-irradiation were investigated. It was shown that interactions in inulin with OH radicals are principally responsible for radiolytic decomposition of inulin. The data on radiolysis of more simple model systems were used to make available decomposition spectra of γ-irradiated aerated aqueous solution of inulin. 9 refs., 6 figs

  11. Radiolysis: an efficient method of studying radicalar antioxidant mechanisms

    International Nuclear Information System (INIS)

    Gardes-Albert, M.; Jore, D.

    1998-01-01

    The use of the radiolysis method for studying radicalar antioxidant mechanisms offers the different following possibilities: 1- quantitative evaluation of antioxidant activity of molecules soluble in aqueous or non aqueous media (oxidation yields, molecular mechanisms, rate constants), 2- evaluation of the yield of prevention towards polyunsaturated fatty acids peroxidation, 3- evaluation of antioxidant activity towards biological systems such as liposomes or low density lipoproteins (LDL), 4- simple comparison in different model systems of drags effect versus natural antioxidants. (authors)

  12. Hazards of plutonium and fuel reprocessing

    International Nuclear Information System (INIS)

    Watson, G.M.

    1978-01-01

    Apart from the possibility that civil plutonium may be diverted to military use the main argument against the introduction of a plutonium economy seems to be the supposedly unmanageable biological risk attached to plutonium itself. The author points out weaknesses in many of the opponents' arguments against the increased use of plutonium and argues that current safety practices are more than adequate in handling plutonium and other radioactive materials

  13. Recovery of plutonium by pyroredox processing

    International Nuclear Information System (INIS)

    McNeese, J.A.; Bowersox, D.F.; Christensen, D.C.

    1985-09-01

    Using pyrochemical oxidation and reduction, we have developed a process to recover the plutonium in impure scrap with less than 95% plutonium. This plutonium metal was further purified by pyrochemical electrorefining. During development of the procedures, depleted electrorefining anodes were processed, and over 80% of the plutonium was recovered as high-purity metal in one electrorefining cycle. Over 40 kg of plutonium has been recovered from 55 kg of impure anodes with our procedures. 6 refs., 7 figs., 4 tabs

  14. Recovery of plutonium by pyroredox processing

    International Nuclear Information System (INIS)

    McNeese, J.A.; Bowersox, D.F.; Christensen, D.C.

    1985-01-01

    Using pyrochemical oxidation and reduction, we have developed a process to recover the plutonium in impure scrap with less than 95% plutonium. This plutonium metal was further purified by pyrochemical electrorefining. During development of the procedures, depleted electrorefining anodes were processed, and over 80% of the plutonium was recovered as high-purity metal in one electrorefining cycle. Over 40 kg of plutonium has been recovered from 55 kg of impure anodes with our procedures. 6 refs., 2 figs., 5 tabs

  15. Probing phonons in plutonium

    International Nuclear Information System (INIS)

    Wong, Joe; Krisch, M.; Farber, D.; Occelli, F.; Schwartz, A.; Chiang, T.C.; Wall, M.; Boro, C.; Xu, Ruqing

    2010-01-01

    Plutonium (Pu) is well known to have complex and unique physico-chemical properties. Notably, the pure metal exhibits six solid-state phase transformations with large volume expansions and contractions along the way to the liquid state: α → β → γ → (delta) → (delta)(prime) → (var e psilon) → liquid. Unalloyed Pu melts at a relatively low temperature ∼640 C to yield a higher density liquid than that of the solid from which it melts, (Figure 1). Detailed understanding of the properties of plutonium and plutonium-based alloys is critical for the safe handling, utilization, and long-term storage of these important, but highly toxic materials. However, both technical and and safety issues have made experimental observations extremely difficult. Phonon dispersion curves (PDCs) are key experimenta l data to the understanding of the basic properties of Pu materials such as: force constants, sound velocities, elastic constants, thermodynamics, phase stability, electron-phonon coupling, structural relaxation, etc. However, phonon dispersion curves (PDCs) in plutonium (Pu) and its alloys have defied measurement for the past few decades since the discovery of this element in 1941. This is due to a combination of the high thermal-neutron absorption cross section of plutonium and the inability to grow the large single crystals (with dimensions of a few millimeters) necessary for inelastic neutron scattering. Theoretical simulations of the Pu PDC continue to be hampered by the lack of suitable inter -atomic potentials. Thus, until recently the PDCs for Pu and its alloys have remained unknown experimentally and theoretically. The experimental limitations have recently been overcome by using a tightly focused undulator x-ray micro-beam scattered from single -grain domains in polycrystalline specimens. This experimental approach has been applied successfully to map the complete PDCs of an fcc d-Pu-Ga alloy using the high resolution inelastic x-ray scattering (HRIXS

  16. Radiolysis effects in sub-cooled nucleate boiling

    International Nuclear Information System (INIS)

    Dickinson, S.; Henshaw, J.; Tuson, A.; Sims, H.E.

    2002-01-01

    A hydrogen depleted region may form in the water during bubble formation when boiling occurs in a PWR. This would arise from stripping of gases into the steam phase. The depleted water may then become oxidising due to radiolysis forming H 2 O 2 . The presence of radiolytic oxidising conditions is one of the mechanisms proposed to explain deposits formed in Axial Offset Anomalies. This work describes a model that has been developed to examine this behaviour. The model deals with bubble growth and material transport as well as the radiolysis chemistry. The model simulates diffusion of species through the gas/liquid boundary layer. The appropriate mass conservation equations for this problem are described and the results of their numerical solution discussed. This model indicates the importance of the assumed boundary conditions on the results of the calculations. These boundary conditions are discussed in detail and the most appropriate ones for the actual reactor situation are outlined. The conclusion of this modelling study is that at normal PWR operating conditions of 40 cc H 2 (STP) kg -1 it is unlikely that radiolysis in a subcooled boiling region would be important. The situation is more ambiguous at the 1 to 5 cc H 2 (STP) kg -1 range. (author)

  17. Radiolysis effects in sub-cooled nucleate boiling

    Energy Technology Data Exchange (ETDEWEB)

    Dickinson, S.; Henshaw, J.; Tuson, A.; Sims, H.E. [AEA Technology (United Kingdom)

    2002-07-01

    A hydrogen depleted region may form in the water during bubble formation when boiling occurs in a PWR. This would arise from stripping of gases into the steam phase. The depleted water may then become oxidising due to radiolysis forming H{sub 2}O{sub 2}. The presence of radiolytic oxidising conditions is one of the mechanisms proposed to explain deposits formed in Axial Offset Anomalies. This work describes a model that has been developed to examine this behaviour. The model deals with bubble growth and material transport as well as the radiolysis chemistry. The model simulates diffusion of species through the gas/liquid boundary layer. The appropriate mass conservation equations for this problem are described and the results of their numerical solution discussed. This model indicates the importance of the assumed boundary conditions on the results of the calculations. These boundary conditions are discussed in detail and the most appropriate ones for the actual reactor situation are outlined. The conclusion of this modelling study is that at normal PWR operating conditions of 40 cc H{sub 2} (STP) kg{sup -1} it is unlikely that radiolysis in a subcooled boiling region would be important. The situation is more ambiguous at the 1 to 5 cc H{sub 2} (STP) kg{sup -1} range. (author)

  18. Radiolysis of simple quaternary ammonium salt components of Amberlite resin

    International Nuclear Information System (INIS)

    Dhiman, Surajdevprakash B.; LaVerne, Jay A.

    2013-01-01

    The radiation chemical yields of gaseous products, H 2 and CH 4 , in the radiolysis of dry methylammonium chloride, dimethylammonium chloride, trimethylammonium chloride, tetramethylammonium chloride and benzyl trimethylammonium chloride by γ-rays and 5 MeV helium ions have been investigated. Some of these amines are the different components of the quaternary ammonium resin Amberlite, which is a strongly basic anion exchange resin based on a polystyrene divinylbenzene copolymer. Molecular hydrogen yields with γ-radiolysis range from a high of 4.43 molecules per 100 eV for trimethylammonium chloride to 0.07 and 0.05 molecules per 100 eV for tetramethylammonium chloride and benzyl trimethylammonium chloride, respectively. Yields of methane gas are generally negligible except for trimethylammonium chloride and tetramethylammonium chloride, 0.26 and 0.02 molecules per 100 eV, respectively. Isotopic labeling studies suggest that the first step in H 2 production is the breakage of the N-H bond followed by abstraction of H · atom from the methyl groups. EPR analysis shows the formation of both N and C centered radicals. A comparison is made between the radiolysis of Amberlite and its various components

  19. Pulse radiolysis of solutions of trans-stilbene

    International Nuclear Information System (INIS)

    Langan, J.R.; Salmon, G.A.

    1982-01-01

    On pulse radiolysis of solutions of trans-stilbene (t-St) in THF the radical-anion of t-St is formed by reaction of e - sub(s) with t-St. The transient absorption spectrum observed with lambdasub(max) at 500 and 720 nm is attributed to the unassociated St - . The subsequent decay of the radical-anion is accounted for by reaction with the counter-cation of THF formed on radiolysis and with radiolytically generated radicals; rate constants for these processes are estimated. Addition of sodium tetrahydridoaluminate (NAH) results in the radical-anion being associated with Na + as a contact ion-pair and a shift of lambdasub(max) to 490 nm. In the presence of the lithium salt the absorption spectrum of the radical-anion reverts to 500 nm. On pulse radiolysis of solutions containing NAH the main reaction forming St - is that of (Na + , e - sub(s))ion pairs with t-St. In addition there is a delayed formation of St - over a period of microseconds. The presence of tetrahydridoaluminate salts also greatly enhances the stability of St - and at high doses per pulse little decay was observed over 700 μs. The variation of G(St - ) with [NAH] was studied and was found to attain a plateau value of 2.0 at the higher concentrations. (author)

  20. A method for the gravimetric determination of plutonium in pure plutonium nitrate concentrate solution

    International Nuclear Information System (INIS)

    Mair, M.A.; Savage, D.J.

    1986-12-01

    Plutonium nitrate solution is treated with sulphuric acid before being heated and finally ignited. The stoichiometric plutonium dioxide so formed is weighed and hence the plutonium content is calculated. (author)

  1. Plutonium contaminated materials research programme

    International Nuclear Information System (INIS)

    Higson, S.G.

    1986-01-01

    The paper is a progress report for 1985 from the Plutonium Contaminated Materials Working Party (PCMWP). The PCMWP co-ordinates research and development on a national basis in the areas of management, treatment and immobilisation of plutonium contaminated materials, for the purpose of waste management. The progress report contains a review of the development work carried out in eight areas, including: reduction of arisings, plutonium measurement, sorting and packaging, washing of shredded combustible PCM, decommissioning and non-combustible PCM treatment, PCM immobilisation, treatment of alpha bearing liquid wastes, and engineering objectives. (UK)

  2. Plutonium again (smuggling and movements)

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    A link is discounted between nuclear proliferation and the recently discovered smuggled plutonium from the former Soviet Union at Munich airport and other places in Germany. It is argued that governments wishing to obtain nuclear materials to develop a weapons programme would not arrange to have it smuggled in a suitcase. Instead, it is speculated that a link exists between the plutonium smuggling incidents and the desire to promote the production of mixed oxide (MOX) fuel. Such incidents, by further raising public anxiety, may be intended to turn public opinion in favour of MOX fuel production as a sensible way of getting rid of surplus plutonium. (UK)

  3. Learning more about plutonium; En savoir plus sur le plutonium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This digest brochure explains what plutonium is, where it comes from, how it is used, its recycling into Mox fuel, its half life, historical discovery, its presence in the environment, toxicity and radioactivity. (J.S.)

  4. Radiolysis of concentrated solutions. 1. Pulse and γ radiolysis studies of direct and indirect effects in LiCl solutions

    International Nuclear Information System (INIS)

    Pucheault, J.; Ferradini, C.; Julien, R.; Deysine, A.; Gilles, L.; Moreau, M.

    1979-01-01

    This study of the radiolysis of concentrated aqueous LiCl solutions enables the relative contributions of the direct and indirect effects to be evaluated as a function of Cl - concentration and also permits an evaluation of the role of Cl - in the early stages of water radiolysis. Radicalar and molecular yields G/sub Cl 2 - /, G/sub OH/, G//sub e//sub aq/ - / + G/sub H/, G/sub H 2 O 2 /, and G/sub H 2 / are determined for all concentrations employed, and the material balance is verified. The main conclusions concerning the apparent inefficacy of the direct effect and the importance of OH scavenging in spurs are discussed

  5. Concentration and purification of plutonium solutions by means of ion-exchange columns

    Energy Technology Data Exchange (ETDEWEB)

    Durham, R W; Aikin, A M

    1953-02-15

    Equilibrium experiments using Dowex 50 ion-exchange resin and nitric acid solutions of Pu{sup 3+}, UO{sub 2}{sup 2+}, Fe{sup 2+} cations have yielded values for the absorption affinities for these ions. Trivalent plutonium was found to be far more strongly absorbed than UO{sub 2}{sup 2+} and Fe{sup 2+}. Column studies have shown that uranium can be completely separated from plutonium even when the initial concentration of uranium is very much greater than that of the plutonium. A plutonium concentration increase of about fifty-fold can be obtained from solutions about 10{sup -3} M in plutonium and 1.0M in nitric acid. The equation K{sub Pu}{sup 3+} = X{sub R} (1-X{sub S}){sup 3} C{sub S}{sup 2}/X{sub S} (1-X{sub R}){sup 3} C{sub R}{sup 2} for estimating the maximum amount of plutonium taken up by a column of resin of unit volume from a solution of total equivalent concentration, C{sub S} , has been shown to hold for values of C{sub S} up to 3 equivalents per litre. X{sub R}, the equivalent fraction of plutonium on the resin, is the number of equivalents of plutonium absorbed by the resin divided by the total capacity of the column. X{sub S}, the equivalent fraction of plutonium in solution, is the equivalent concentration of plutonium divided by the total equivalent concentration of cations in solution. C{sub R} is the total capacity of the resin in milli-equivalents per gram of dry resin. Recommendations have been made for the application and operation of ion-exchange columns in the Plutonium-Extraction Plant. (author)

  6. The possible effects of alfa and beta radiolysis on the matrix dissolution of spent nuclear fuel

    International Nuclear Information System (INIS)

    Grenthe, I.; Puigdomenech, I.; Bruno, J.

    1983-01-01

    The effects of oxidants on the retainment of actinides in a nuclear repository have been modelled by using an equilirium procedure. The oxidants are formed as a result of α- and #betta#-radiolysis when spent nuclear fuel is exposed to ground water. From an equilibrium point of view, the strongest reductants in the system (Zr, Pb and Cu) are expected to be oxidized first, leaving the actinoids in the oxidation states they have in the fuel matrix. This is expected to result in a negligible mobilization of the actinoids due to the very low solubility of the MO 2 oxides. However, the formation of protective layers of oxides will most likely decrease the effectiveness of the metallic reducing agents. This will lead to an increased oxidation of the spent fuel which results in an increased actinoid mobilization. The results of the equilibrium calculations show that the oxidation of the fuel matrix results in the formation of UO 2 (OH) 2 (s) and to the formation of the soluble complex UO 2 (CO 3 ) 3 4 . The transport of uranium is limited by the total concentration of carbonate in the aqueous phase. Neptunium may be quantitatvely solubilized as various Np(V) species and transported by ground water from the repository. Plutonium is retained at the repository site as insoluble PuO 2 . Only very small amounts are transported by ground water. The mobile actinoids may be reprecipitated when they encounter reducing conditions along the flow path. The conditions for repricipitation for typical ground water compositions have been modelled by using solubility - pe diagrams. (Authors)

  7. Plutonium waste container identification

    International Nuclear Information System (INIS)

    Schmierer, T.J.

    1979-01-01

    The purpose of this paper is to define the parameters of a method for identifying plutonium waste containers. This information will form the basis for a permanent committee to develop a complete identification program for use throughout the world. Although a large portion of the information will be on handwritten notebooks and may not be as extensive as is desired, it will all be helpful. The final information will be programmed into computer language and be available to all interested parties as well as a central control committee which will have the expertise to provide each government with advice on the packaging, storage, and measurement of the waste for which it is responsible. As time progresses, this central control committee should develop permanent storage sites and establish a system of records which will last for hundreds of years

  8. Uranium plutonium oxide fuels

    International Nuclear Information System (INIS)

    Cox, C.M.; Leggett, R.D.; Weber, E.T.

    1981-01-01

    Uranium plutonium oxide is the principal fuel material for liquid metal fast breeder reactors (LMFBR's) throughout the world. Development of this material has been a reasonably straightforward evolution from the UO 2 used routinely in the light water reactor (LWR's); but, because of the lower neutron capture cross sections and much lower coolant pressures in the sodium cooled LMFBR's, the fuel is operated to much higher discharge exposures than that of a LWR. A typical LMFBR fuel assembly is shown. Depending on the required power output and the configuration of the reactor, some 70 to 400 such fuel assemblies are clustered to form the core. There is a wide variation in cross section and length of the assemblies where the increasing size reflects a chronological increase in plant size and power output as well as considerations of decreasing the net fuel cycle cost. Design and performance characteristics are described

  9. The plutonium ban

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    'Nuclear Power Issues and Choices' is the title of a recent report which has been performed by a study group sponsored by the Ford Foundation and administered by the MITRE Corporation. The main concern of this study is to prevent the proliferation of nuclear weapons. Since the reprocessing of spent fuel elements yields among others plutonium of bomb quality, the report of the Ford Foundation comes to the conclusion that the USA should defer the closing of the fuel cycle, defer the reprocessing of spent nuclear fuel, deposit the spent fuel elemenets as a whole, and defer the breeder which can not run without fuel reprocessing. The German attitude however is that we can not relinquish on reprocessing and recycling of nuclear fuel because we are lacking such rich resources of coal, oil and uranium as the USA have. Furthermore, the deposition of spent fuel elements may be more dangerous than the deposition of the radioactive waste from reprocessing plants. (orig.) [de

  10. Study by γ radiolysis and pulsed radiolysis of the reactivity of the superoxide ion in the oxyhemoglobin-methemoglobin system

    International Nuclear Information System (INIS)

    Haristoy, Didier.

    1976-01-01

    γ radiolysis of aqueous solutions of methemoglobin (MetHb) in the presence of formate ions, shows that only 25% of the total protein is reduced in oxyhemoglobin (HbO 2 ) by superoxide ions O 2 - according to the reaction MetHb+O 2 - →HbO 2 . The result can be attributed neither to the reactions of O 2 - with HbO 2 , nor the oxidation of HbO 2 by H 2 O 2 produced in the radiolysis of water and by dismutation of O 2 - . Pulse radiolysis studies of this reaction strongly suggest the formation of a transient complex 'MetHbO 2 - ' during the reaction. In addition to the well known self-oxidation of HbO 2 , these results show the existence of an equilibrium between HbO 2 and MetHb+O 2 - . Such an equilibrium could give rise, 'in vivo' to a nearly steady concentration of superoxide ions which could initiate a reaction favoring oxidation by oxygen [fr

  11. Differential spectrophotometric determination of plutonium

    International Nuclear Information System (INIS)

    Lecat, J.

    1980-01-01

    Differential spectrophotometric method is used for determination of plutonium reduced to oxydation state III+ by ascorbic acid, at 560 nm. Concentration of solutions is 4 g/l and accuracy of the method is better than 0,3% [fr

  12. Technological alternatives for plutonium transport

    International Nuclear Information System (INIS)

    1978-12-01

    This paper considers alternative transport modes (air, sea, road, rail) for moving (1) plutonium from a reprocessing plant to a store or a fuel fabrication facility, and (2) MOX fuel from the latter to a reactor. These transport modes and differing forms of plutonium are considered in terms of: their proliferation resistance and safeguards; environmental and safety aspects; and economic aspects. It is tentatively proposed that the transport of plutonium could continue by air or sea where long distances are involved and by road or rail over shorter distances; this would be acceptable from the non-proliferation, environmental impact and economic aspects - there may be advantages in protection if plutonium is transported in the form of mixed oxide

  13. Plutonium helps probe protein, superconductor

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Scientists are finding that plutonium can be a useful research tool that may help them answer important questions in fields as diverse as biochemistry and solid-state physics. This paper reports that U.S. research involving plutonium is confined to the Department of Energy's national laboratories and centers around nuclear weapons technology, waste cleanup and disposal, and health effects. But at Los Alamos National Laboratory, scientists also are using plutonium to probe the biochemical behavior of calmodulin, a key calcium-binding protein that mediates calcium-regulated processes in biological systems. At Argonne National Laboratory, another team is trying to learn how a superconductor's properties are affected by the 5f electrons of an actinide like plutonium

  14. An alternative plutonium disposition method

    International Nuclear Information System (INIS)

    Kueppers, C.

    2002-01-01

    This paper provides a feasibility study on vitrification of plutonium with high active waste concentrate, and fabrication of MOX fuel rods for direct final disposal. These are potential alternatives to the direct use of MOX fuel in a reactor. (author)

  15. Chloride removal from plutonium alloy

    International Nuclear Information System (INIS)

    Holcomb, H.P.

    1983-01-01

    SRP is evaluating a program to recover plutonium from a metallic alloy that will contain chloride salt impurities. Removal of chloride to sufficiently low levels to prevent damaging corrosion to canyon equipment is feasible as a head-end step following dissolution. Silver nitrate and mercurous nitrate were each successfully used in laboratory tests to remove chloride from simulated alloy dissolver solution containing plutonium. Levels less than 10 ppM chloride were achieved in the supernates over the precipitated and centrifuged insoluble salts. Also, less than 0.05% loss of plutonium in the +3, +4, or +6 oxidation states was incurred via precipitate carrying. These results provide impetus for further study and development of a plant-scale process to recover plutonium from metal alloy at SRP

  16. Graphic-analytical determination of statics of reduction reextraction of plutonium using iron(2) as a reducing agent

    International Nuclear Information System (INIS)

    Pochinajlo, A.

    1977-01-01

    The grafic technological scheme of reduction reextraction of plutonium has been designed and the experiments on the laboratory 16-staged extractor of a mixer-settler type have been carried. From the concentration profiles found for a steady stage the content of plutonium(4) and plutonium(3) in organic and water phases in every stage is calculated. Then using the equations of material balance and extraction equilibrium a kinetic formula describing the reduction of plutonium(4) by iron(2f.) in a separate stage is deduced. Since the kinetic parameter A has been found to be close for all the staqes the analytical expression has been obtained with the help of which it is possible to determine a priori the plutonium(4) concentration profile in a reextraction part of the extractor for the given technological process conditions characterized by the defenite A. The plutonium(4) concentration profiles for the organic phase with different values A are presented

  17. Low-level detection and quantification of Plutonium(III, IV, V,and VI) using a liquid core waveguide

    International Nuclear Information System (INIS)

    Wilson, Richard E.; Hu, Yung-Jin; Nitsche, Heino

    2003-01-01

    Understanding the aqueous chemistry of plutonium, in particular in environmental conditions, is often complicated by plutonium's complex redox chemistry. Because plutonium possesses four oxidation states, all of which can coexist in solution, a reliable method for the identification of these oxidation states is needed. The identification of plutonium oxidation states at low levels in aqueous solution is often accomplished through an indirect determination using series of liquid-liquid extraction procedures using oxidation state specific reagents such as HDEHP and TTA. While these methods, coupled with radioactive counting techniques provide superior limits of detection they may influence the plutonium redox equilibrium, are time consuming, waste intensive and costly. Other analytical methods such as mass spectrometry and radioactive counting as stand alone methods provide excellent detection limits but lack the ability to discriminate between the oxidation states of the plutonium ions in solution

  18. Inhaled plutonium oxide in dogs

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    This project is concerned with long-term experiments to determine the life-span dose-effect relationships of inhaled 239 PuO 2 and 238 PuO 2 in beagles. The data will be used to estimate the health effects of inhaled transuranics. The tissue distribution of plutonium, radiation effects in the lung and hematologic changes in plutonium-exposed beagles with lung tumors were evaluated

  19. Plutonium contamination in italian population

    International Nuclear Information System (INIS)

    Cave-Bondi, G.; Merli, S.; Rogo, M.; Sgarbazzini, M.; Clemente, G.F.; Mancini, L.; Santori, G.; Tardella, Q.

    1983-01-01

    The literature data concerning the biological and the chemical physical characteristics of plutonium are summarized in the first part of the paper. The experimental results of the plutonium concentration in complete diets, single food items and some human autopsy tissues, regarding the Italian situation, are then presented and discussed. Our experimental data are in good agreement with similar data reported in several studies carried out in some countries of the north emisphere

  20. Plutonium: real and false problems

    International Nuclear Information System (INIS)

    Bemden, E. van den

    1981-01-01

    This paper deals with technical and technological state of the possibilities of using plutonium as fuel in the thermal and fast reactors. It also describes the political blockage restraining its use and the reasons for it. The accent is put on some fundamental lacks of international coordination and on some problems of commercial policy, which impede, in a certain way, the industrial use of plutonium as a fuel. (author)

  1. Monitoring the risks of plutonium

    International Nuclear Information System (INIS)

    Holliday, B.

    1978-01-01

    The difficulties in monitoring the environment in work areas where plutonium is handled are identified and both continuous and personal air sampling techniques considered. Methods of estimating the amounts of plutonium retained in the body are: (1) Direct external counting over the chest of the 'soft' low energy X-rays and gamma rays emitted by the plutonium deposited in the lungs. (2) Measuring plutonium excreted in urine. (3) Analysing faeces soon after a suspected contamination. Limitation of these techniques are discussed and it is shown that estimating the amount of plutonium in the body, or a specific organ, is extremely difficult, both because of the lack of sensitivity of the measuring techniques (especially chest scanning) and because of the problems in interpreting data, stemming from a lack of knowledge of crucial characteristics of the inhaled plutonium (such as particle size and solubility). Nevertheless it is felt that the judicious integration of all the options creates a level of certainty that no individual technique can possibly inspire. (U.K.)

  2. Atomic energy policy of Japan, especially plutonium utilization policy

    International Nuclear Information System (INIS)

    Moriguchi, Y.

    1993-01-01

    The necessity of plutonium use in Japan is discussed. Basic policy regarding plutonium use and future plutonium utilization programme is described including such an aspect as management of plutonium from dismantled nuclear weapons

  3. PULSE RADIOLYSIS IN SUPERCRITICAL RARE GAS FLUIDS

    International Nuclear Information System (INIS)

    HOLROYD, R.

    2007-01-01

    Recently, supercritical fluids have become quite popular in chemical and semiconductor industries for applications in chemical synthesis, extraction, separation processes, and surface cleaning. These applications are based on: the high dissolving power due to density build-up around solute molecules, and the ability to tune the conditions of a supercritical fluid, such as density and temperature, that are most suitable for a particular reaction. The rare gases also possess these properties and have the added advantage of being supercritical at room temperature. Information about the density buildup around both charged and neutral species can be obtained from fundamental studies of volume changes in the reactions of charged species in supercritical fluids. Volume changes are much larger in supercritical fluids than in ordinary solvents because of their higher compressibility. Hopefully basic studies, such as discussed here, of the behavior of charged species in supercritical gases will provide information useful for the utilization of these solvents in industrial applications

  4. Partitioning of plutonium and uranium in aqueous medium using hydroxyurea as reducing agent

    International Nuclear Information System (INIS)

    Sivakumar, P.; Subba Rao, R.V.; Meenakshi, S.

    2012-01-01

    A new process for the partitioning of plutonium and uranium during the reprocessing of spent fuel discharged from fast reactor was optimised using hydroxyurea (HU) as a reductant. Stoichiometric ratio of HU required for the reduction of Pu(IV) was studied. The effect of concentration of uranium, plutonium and acidity on the distribution ratio (Kd) of Pu in the presence of HU was studied. The effect of HU in further purification of Pu such as solvent extraction and precipitation of plutonium as oxalate was also studied. The results of the study indicate that Pu and U can be separated from each other using HU as reductant. (author)

  5. Plutonium re-cycle in HTR

    Energy Technology Data Exchange (ETDEWEB)

    Desoisa, J. A.

    1974-03-15

    The study of plutonium cycles in HTRs using reprocessed plutonium from Magnox and AGR fuel cycles has shown that full core plutonium/uranium loadings are in general not feasible, burn-up is limited due the need for lower loadings of plutonium to meet reload core reactivity limits, on-line refueling is not practicable due to the need for higher burnable poison loadings, and low conversion rates in the plutonium-uranium cycles cannot be mitigated by axial loading schemes so that fissile make-up is needed if HTR plutonium recycle is desired.

  6. A pulse radiolysis study of the formation and reactions of reduced metal EDTA complexes

    International Nuclear Information System (INIS)

    Buitenhuis, R.

    1977-01-01

    The construction of a computerized pulse radiolysis system with available means appropriate for the wavelength interval between 300 and 1000 nm is described. The investigation of the radiolysis of aqueous solutions of EDTA complexes in the presence of alcohols is discussed

  7. Determination of uranium and plutonium in urine of people working with regenerated uranium

    International Nuclear Information System (INIS)

    Golutvina, M.M.; Ryzhova, E.A.

    1987-01-01

    Method of determining uranium and plutonium content in urine with their combined presence up to α-activity ratio Pu:U=1:100 is developed. The method is based on extraction chromatographic separation of nuclides using trimethyloctylammonium nitrate and their subsequent α-spectrometric determination. The coefficient of plutonium purification from uranium makes up 750. Chemical yield of Pu is 72±6%, U-76±8%. The method sensitivity is 0.2 decompositions per minute for a sample

  8. Dynamics of mobile form of plutonium isotopes in soils within 10-km zone of Chernobyl NPP

    International Nuclear Information System (INIS)

    Shuktomova, I.I.

    1996-01-01

    The dynamics of the mobile forms of plutonium isotopes depending on the time of there presence in environment were studied on samples of five soil varieties within the limits of the 10-km zone of Chernobyl NPP. Seasonal dynamic study of the extracted plutonium isotopes showed the increase (5-10 fold) in the amount of mobile forms of radionuclides in all soil samples. Studying the dynamics of total sum of mobile forms of isotopes in soils showed their decrease in general

  9. Spectrophotometric determination of plutonium with chlorophosphonazo III in n-pentanol

    International Nuclear Information System (INIS)

    Saponara, N.M.; Marsh, S.F.

    1982-03-01

    Microgram amounts of plutonium are measured spectrophotometrically as the plutonium-chlorophosphonazo III complex after extraction into n-pentanol from 1.5 M HCl. The relative standard deviation is 1.5% for the range of 2.5 to 17.5 μg. The tolerance is excellent for many metals and nonmetals present in nuclear fuel-cycle materials. A preceding anion-exchange-column separation increases tolerance for certain metals and nonmetals

  10. Study of the effect of water radiolysis on zirconolite dissolution

    International Nuclear Information System (INIS)

    Tribet, M.

    2007-09-01

    Zirconolite is one of the matrices foreseen for the confinement of minor actinides in case of deep geological disposal. Indeed, zirconolite (general formula: CaZr x Ti 3-x O 7 (0.8 ≤ x ≤ 1.37)) is able to incorporate rare earth elements and actinides by substitution in calcium and zirconium sites and, moreover, its chemical durability into water is well known. However, in case of deep geological disposal, after a long period, water can reach the confinement matrix and can be radiolysed at the moment of the radionuclide alpha decays. In this work we have thus studied the effects of water radiolysis induced by charged particles (alphas or protons) on the dissolution of a synthetic sintered zirconolite. The formula of this zirconolite is Ca 0,8 Nd 0,2 ZrTi 1,8 Al 0,2 O 7 where Nd simulates the presence of trivalent and tetravalent actinides. We performed the irradiations with external ion beams in two distinct geometries where the fluences ranged from 10 15 to 10 16 ions.cm -2 . In the first geometry the beam stops into water before the surface/water interface. In the second one the beam gets through the sample before stopping at the surface/water interface. The use of these different configurations allows to study the respective influence of parameters such as sample irradiation, Linear Energy Transfer at the surface/water interface or total deposited energy. The irradiations were performed on both crystalline and amorphous zirconolites in pure water or with complexing species such as F - . The sample dissolution has been monitored through the release of cations. The radiolytic production of H 2 O 2 has also been measured. Our results show that the water radiolysis has an effect on the preferential release of Zr, Ti and Nd: for these elements, releases are one or two order of magnitude higher than releases out of radiolysis. Such preferential releases occur whatever the temperature (20 or 50 C), the surface state (crystalline or amorphous) and the experimental

  11. Erosional losses of fallout plutonium

    International Nuclear Information System (INIS)

    Foster, G.R.; Hakonson, T.E.

    1987-01-01

    Plutonium from fallout after atmospheric explosion of nuclear weapons in the 1950's and 1960s is being redistributed over the landscape by soil erosion and carried on sediment by streams to oceans. Erosion rates computed with the Universal Soil Loss Equation for more than 200,000 sample points on nonfederal land across the US were used to estimate plutonium removal rates by soil erosion. On the average, only about 4% of the eroded sediment reaches the outlet of a major river. The remaining sediment is deposited en route, and because deposition is a selective process, the sediment is enriched in fine particles having the highest concentration of plutonium because of the element's strong association with clay and silt-sized sediment. Estimated enrichment ratios, sediment delivery ratios, and erosion rates were used to estimate annual delivery of fallout plutonium. These estimates ranged from 0.002% of the initial fallout plutonium inventory for the Savannah River basin to 0.01% for the Columbia River basin, to 0.02% for the Hudson and Rio Grande River basins, to 0.08% for the Mississippi River basin. If the deposition of plutonium had been uniformly 1 mCi/km 2 , the estimated plutonium activity on suspended sediment would range from about 7 fCi/g of sediment of the Savannah River basin, to 9 fCi/g for the Mississippi River basin, to 12 fCi/g for the Hudson River basin, to 14 fCi/g for the Columbia and Rio Grande River basins. 45 references, 2 figures, 17 tables

  12. Coolant radiolysis studies in the high temperature, fuelled U-2 loop in the NRU reactor

    International Nuclear Information System (INIS)

    Elliot, A.J.; Stuart, C.R.

    2008-06-01

    An understanding of the radiolysis-induced chemistry in the coolant water of nuclear reactors is an important key to the understanding of materials integrity issues in reactor coolant systems. Significant materials and chemistry issues have emerged in Pressurized Water Reactors (PWR), Boiling Water Reactors (BWR) and CANDU reactors that have required a detailed understanding of the radiation chemistry of the coolant. For each reactor type, specific computer radiolysis models have been developed to gain insight into radiolysis processes and to make chemistry control adjustments to address the particular issue. In this respect, modelling the radiolysis chemistry has been successful enough to allow progress to be made. This report contains a description of the water radiolysis tests performed in the U-2 loop, NRU reactor in 1995, which measured the CHC under different physical conditions of the loop such as temperature, reactor power and steam quality. (author)

  13. Radiolysis of groundwater in a repository for spent fuel - a literature survey

    International Nuclear Information System (INIS)

    Snellman, Margit

    1989-06-01

    This review on radiolysis considers both the fundamental mechanisms and theory involved in radiolysis of pure water and systems containing major species existing in repository conditions. The amount of different molecules and radicals formed in radiolysis of water is a complex function of the type of radiation and dose rate, pH and ionic strength of water. The principal effects of the species present in water are to scavenge the radiolytic intermediates and products producing new species and changing the yield of radical and molecular products. Of the metals (Cu, Fe) and inorganic ions (Cl - , HCO 3 - /CO 3 2- , NH 3 /NO 2 - ) considered, iron is the most important one and can participate in a number of reactions both with the primary and secondary radiolysis products and may effect both the H 2 and H 2 O 2 yield. For the estimation of the overall effect of radiolysis in the repository both calculations and supporting experimental work is needed

  14. Fenton-enhanced {gamma}-radiolysis of cyanuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Varghese, Rani [School of Chemical Sciences, Mahatma Gandhi University, Kottayam 686560, Kerala (India); Aravind, Usha K. [School of Chemical Sciences, Mahatma Gandhi University, Kottayam 686560, Kerala (India); Aravindakumar, Charuvila T. [School of Chemical Sciences, Mahatma Gandhi University, Kottayam 686560, Kerala (India)]. E-mail: CT-Aravindakumar@rocketmail.com

    2007-04-02

    Degradation of cyanuric acid (OOOT), a stable end product of oxidative decomposition of atrazine, is investigated in a combined field of gamma radiolysis and fenton reaction. The reaction of hydroxyl radical ({center_dot}OH) at pH 6 was carried out by irradiating N{sub 2}O saturated aqueous solutions containing OOOT (1 x 10{sup -3} mol dm{sup -3}), and this resulted only a marginal degradation (20%). However, when the same reaction was carried out in the presence of varying concentrations of ferrous sulfate ((5-10) x 10{sup -5} mol dm{sup -3}), the decay of OOOT has been enhanced to more than 80%. This decay followed a first order kinetics. Nearly similar effects were observed with another triazine derivative, 2,4-dioxohexahydro-1,3,5-triazine (DHT). Two major reaction mechanisms are proposed for the enhanced decay of OOOT. The formation of unstable hydroxyl radical adducts from the reaction of {center_dot}OH which is the result of gamma radiolysis and the Fenton reaction (resulting from the reaction of the added Fe(II) and of the H{sub 2}O{sub 2} from the radiolysis of water), is proposed as the first mechanism. The second mechanism, which is likely the major contributor to degradation, is proposed as the reaction of a nucleophilic adduct, Fe(II)OOH, which could directly react with the electron deficient triazine ring. It is highlighted that such degradation reactions must be explored for the complete degradation of the byproducts of the oxidative decomposition of atrazine.

  15. Radiolysis in nature: Evidence from the Oklo natural reactors

    International Nuclear Information System (INIS)

    Curtis, D.B.; Gancarz, A.J.

    1983-02-01

    An examination of the mineralogy of the reactor zones at Oklo shows that they have been significantly altered. The rocks immediately adjacent to these zones are also mineralogically modified with respect to normal uranium bearing rocks. The mineralogic changes appear to be the consequence of radiation damage, changes in the bulk chemistry of the system and increased temperatures. Chemical changes were the consequence of convectively circulating fluids that transported elements in and out of the rocks. There were also changes in the electrochemical conditions in the rocks. These changes can most reasonably be attributed to oxidizing and reducing species produced by the radiolysis of water. We have calculated radiation doses and examined the production of radiolysis products in the fluid phase which lead to the following conclusions: 1) There was a net reduction of iron, probably associated with a net increase in total iron in the rocks of the reactor zones. The reduction of iron was most likely the result of hydrogen produced by the radiolysis of water. 2) Commensurate with the iron reduction, there was an oxidation of uranium and multivalent fission products, resulting in their transport out of the reactor zone. 3) Approximately 10 percent of the uranium and various proportions of these fission products were removed and redeposited in rocks within a few meters of the reactor zones. 4) The calculated radiation doses from alpha radiation and the inferred hydrogen production suggest an effective radiation yield of 0.06 molecules of hydrogen per 100 eV of energy imparted to the fluid phase. Considering radiation from both alpha and beta sources, the G value for hydrogen production is reduced to 0.01 to 0.002 molecules H 2 /100 eV. (author)

  16. Pulse radiolysis studies on DNA-Binding radioprotectors

    International Nuclear Information System (INIS)

    Anderson, R.F.

    1996-01-01

    Full text: Hoechst 33342 and newly-synthesised analogues exhibit radioprotective activity in cultured cells and in vivo, as described in accompanying abstracts. These minor groove binding ligands bind at discreet sites in DNA, characterised by 3 to 4 consecutive AT base pairs, and DNA sequencing studies have shown focussed radioprotection at these binding sites. There is evidence that the bound ligands also confer more 'global' protection including the intervening DNA between the binding sites. The observed focussed radioprotection could be explained by H-atom donation from the ligand to radiation-induced carbon-centred deoxyribosyl radicals, but this mechanism is unlikely to account for the global radioprotection. We now report pulse radiolysis studies on another possible mechanism, namely reduction of transient radiation-induced oxidising species on DNA by the ligand, which is consistent with the report of reduction of G + by TMPD. Oxidation of deoxyguanosine (dG) by Br 2 - , produced by radiolysis of Br- in N 2 0-saturated solutions, in the presence of Hoechst 33342 results in the appearance of a transient ligand species which is kinetically resolvable from that obtained from direct oxidation of Hoechst 33342 by Br 2 - . A plot of reaction rate versus ligand concentration indicates that the rate constant for reduction of G + is approximately 3 x 10 8 dm 3 M -1 sec -1 . Similar experiments with DNA, rather than dG, also revealed a transient species corresponding to oxidation of the ligand, but the absolute rate of oxidation was considerably slower for the DNA-bound ligand compared to that for oxidation of the free ligand by G+. These results are clearly consistent with the proposed mechanism of radioprotection by Hoechst 33342 and its analogues, moreover, pulse radiolysis may provide a very useful endpoint for screening new analogues, as a preliminary to radiobiological evaluation

  17. The transport of plutonium nitrate liquor in the UK

    International Nuclear Information System (INIS)

    Barrett, T.R.; Wilson, D.; Bancroft, M.; Higson, J.

    1994-01-01

    The PFR fuel cycle reasons for plutonium nitrate liquor transport are discussed, identifying the pre 1980 'one litre' bottle associated with nuclear R and D activities and then the 250 litre PUNIT transport container to support the PFR fuel cycle. The PUNIT vessel design is discussed, addressing, in particular, the need for clean filling and criticality design features together with the identification of the IAEA transport regulations criteria and the late 1970s testing programme -the full scale drop tests and the model fire tests. Radiolysis is discussed together with the need for inert gas padding. The filling facility and operation are then outlined together with the fissile material accountancy requirements. The shipments and emergency arrangements are then described drawing attention to time and weather constraints. The risk assessment is discussed, together with reference to the Competent Authority (DoT) 'authorisation' and any constraints. A history of the amount of material transferred is then given - relating that to the reprocessing plant operations since 1980. The most satisfactory performance over 12 years is noted. (author)

  18. Plutonium focus area

    International Nuclear Information System (INIS)

    1996-08-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this new approach, EM developed a management structure and principles that led to the creation of specific Focus Areas. These organizations were designed to focus the scientific and technical talent throughout DOE and the national scientific community on the major environmental restoration and waste management problems facing DOE. The Focus Area approach provides the framework for intersite cooperation and leveraging of resources on common problems. After the original establishment of five major Focus Areas within the Office of Technology Development (EM-50, now called the Office of Science and Technology), the Nuclear Materials Stabilization Task Group (EM-66) followed the structure already in place in EM-50 and chartered the Plutonium Focus Area (PFA). The following information outlines the scope and mission of the EM, EM-60, and EM-66 organizations as related to the PFA organizational structure

  19. Plutonium solution analyzer

    International Nuclear Information System (INIS)

    Burns, D.A.

    1994-09-01

    A fully automated analyzer has been developed for plutonium solutions. It was assembled from several commercially available modules, is based upon segmented flow analysis, and exhibits precision about an order of magnitude better than commercial units (0.5%-O.05% RSD). The system was designed to accept unmeasured, untreated liquid samples in the concentration range 40-240 g/L and produce a report with sample identification, sample concentrations, and an abundance of statistics. Optional hydraulics can accommodate samples in the concentration range 0.4-4.0 g/L. Operating at a typical rate of 30 to 40 samples per hour, it consumes only 0.074 mL of each sample and standard, and generates waste at the rate of about 1.5 mL per minute. No radioactive material passes through its multichannel peristaltic pump (which remains outside the glovebox, uncontaminated) but rather is handled by a 6-port, 2-position chromatography-type loop valve. An accompanying computer is programmed in QuickBASIC 4.5 to provide both instrument control and data reduction. The program is truly user-friendly and communication between operator and instrument is via computer screen displays and keyboard. Two important issues which have been addressed are waste minimization and operator safety (the analyzer can run in the absence of an operator, once its autosampler has been loaded)

  20. Plutonium oxide shipment report

    International Nuclear Information System (INIS)

    1979-01-01

    While following procedures for unloading shipping containers containing plutonium oxide, SRP personnel experienced problems. While using a pipe cutter to cut through the wall of the inner container, the pipe section fell to the floor. Three empty food cans in the bottom of the inner canister also fell to the floor and a puff of smoke was observed. Personnel were evacuated and contamination was detected in the room. As a result of the investigations conducted by Westinghouse and SRP, thermal effects, food can coatings, and fuel volatiles were eliminated as the cause of the problem. Helium used to leak test the RL070 shipping container seals entered the inner canister through two weld defects resulting in a pressurization of the contents. When the end cap was removed, the inner canister vented rapidly, the food cans did not, thus creating a differential pressure across the food cans. This caused the food cans to swell. It was recommended that a dye penetrant test of all inner container welds be added. Additional unloading procedures were also recommended

  1. Plutonium solution analyzer

    Energy Technology Data Exchange (ETDEWEB)

    Burns, D.A.

    1994-09-01

    A fully automated analyzer has been developed for plutonium solutions. It was assembled from several commercially available modules, is based upon segmented flow analysis, and exhibits precision about an order of magnitude better than commercial units (0.5%-O.05% RSD). The system was designed to accept unmeasured, untreated liquid samples in the concentration range 40-240 g/L and produce a report with sample identification, sample concentrations, and an abundance of statistics. Optional hydraulics can accommodate samples in the concentration range 0.4-4.0 g/L. Operating at a typical rate of 30 to 40 samples per hour, it consumes only 0.074 mL of each sample and standard, and generates waste at the rate of about 1.5 mL per minute. No radioactive material passes through its multichannel peristaltic pump (which remains outside the glovebox, uncontaminated) but rather is handled by a 6-port, 2-position chromatography-type loop valve. An accompanying computer is programmed in QuickBASIC 4.5 to provide both instrument control and data reduction. The program is truly user-friendly and communication between operator and instrument is via computer screen displays and keyboard. Two important issues which have been addressed are waste minimization and operator safety (the analyzer can run in the absence of an operator, once its autosampler has been loaded).

  2. Plutonium dispositioning in CANDU

    International Nuclear Information System (INIS)

    Boczar, P.G.; Feinroth, H.; Luxat, J.C.

    1995-07-01

    Recently, the U.S. Department of Energy (DOE) sponsored Atomic Energy of Canada Limited (AECL) to evaluate salient technical, strategic, schedule, and cost-related parameters of using CANDU reactors for dispositioning of weapons-grade plutonium in the form of Mixed OXide (MOX) fuel. A study team, consisting of key staff from the CANDU reactor designers and researchers (AECL), operators (Ontario Hydro) and fuel suppliers, analyzed all significant factors involved in such application, with the objective of identifying an arrangement that would permit the burning of MOX in CANDU at the earliest date. One of Ontario Hydro's multi-unit stations, Bruce A nuclear generating station (4x769 MW(e)), was chosen as the reference for the study. The assessment showed that no significant modifications of reactor or process systems are necessary to operate with a full MOX core. Plant modifications would be limited to fuel handling and modifications necessary to accommodate enhanced security and safeguards requirements. No safety limitations were identified

  3. Development of a new picosecond pulse radiolysis system by using a femtosecond laser synchronized with a picosecond linac. A step to femtosecond pulse radiolysis

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Yoichi; Yamamoto, Tamotsu; Miki, Miyako; Seki, Shu; Okuda, Shuichi; Honda, Yoshihide; Kimura, Norio; Tagawa, Seiichi [Osaka Univ., Ibaraki (Japan). Inst. of Scientific and Industrial Research; Ushida, Kiminori

    1997-03-01

    A new picosecond pulse radiolysis system by using a Ti sapphire femtosecond laser synchronized with a 20 ps electron pulse from the 38 MeV L-band linac has been developed for the research of the ultra fast reactions in primary processes of radiation chemistry. The timing jitter in the synchronization of the laser pulse with the electron pulse is less than several picosecond. The technique can be used in the next femtosecond pulse radiolysis. (author)

  4. Pulse radiolysis in model studies toward radiation processing

    Energy Technology Data Exchange (ETDEWEB)

    Sonntag, C Von; Bothe, E; Ulanski, P; Deeble, D J [Max-Planck-Institut fuer Strahlenchemie, Muelheim an der Ruhr (Germany)

    1995-10-01

    Using the pulse radiolysis technique, the OH-radical-induced reactions of poly(vinyl alcohol) PVAL, poly(acrylic acid) PAA, poly(methyacrylic acid) PMA, and hyaluronic acid have been investigated in dilute aqueos solution. The reactions of the free-radical intermediates were followed by UV-spectroscopy and low-angle laser light-scattering; the scission of the charged polymers was also monitored by conductometry. For more detailed product studies, model systems such as 2,4-dihydroxypentane (for PVAL) and 2,4-dimethyl glutaric acid (for PAA) was also investigated. (author).

  5. Gas generation by self-radiolysis of tritiated waste materials

    International Nuclear Information System (INIS)

    Tadlock, W.E.; Abell, G.C.; Steinmeyer, R.H.

    1980-01-01

    Studies simulating the effect of self-radiolysis in disposal packages containing tritiated waste materials show hydrogen to be the dominant gas-phase product. Pressure buildup and gas composition over various tritiated octane and tritiated water samples are designed to give worst case results. One effect of tritium fixation agents is to reduce pressure buildup. The results show that development of explosive gas mixtures is unlikely and that maximum pressure buildup in typical Mound Facility waste packages can be expected to be <0.25 MPa

  6. Isotope effect in gamma-radiolysis of absorbed ammonia

    Energy Technology Data Exchange (ETDEWEB)

    Lyapina, T G; Kotov, A G [Nauchno-Issledovatel' skij Fiziko-Khimicheskij Inst., Moscow (USSR)

    1975-07-01

    The radiolysis of NH/sub 3/ of various isotopic compounds adsorbed on silica gel or zeolite at 77degK was studied. Experimental data were treated using the kinetic equation dR/dt=GI-kIR where R=radical concentration, G=radical yield, k=radical termination constant and I=radiation dose rate. Both the values of G and R for NH/sub 3/ adsorbed on silica gel are affected by the isotopic effect of /sup 15/N, but not on zeolite. The isotopic effect is explained by the influence of protonated acidity of the silica gel surface.

  7. Radiolysis of liquid ammonia in the presence of isopropylalcohol

    Energy Technology Data Exchange (ETDEWEB)

    Dessouki, A M

    1973-09-01

    The effects of variation of dose on the various yields resulting from gamma -irradiation of liquid ammonia and ammoniacal solutions containing isopropanol and N/sub 2/O, NH/sub 4/Cl, NaNO/sub 3/, CH/sub 3/I , Fe (III) or benzophenone were investigated. The G-Values of the primary products resulting from the gamma -radiolysis of ammoniacal solutions containing isopropanol are reported. The G-value of the free electron was calculated and found to be 2.1. Additionally (auth)

  8. Radiolysis of hydrocarbons in liquid phase (Modern state of problem)

    International Nuclear Information System (INIS)

    Saraeva, V.V.

    1986-01-01

    Problems of ionizing radiation effect on hydrocarbons and hydrocarbon systems in a liquid phase are considered. Modern representations on the mechanism of hydrocarbon radiolysis are presented. Electron moderation and ion-electron pair formation, behaviour of charged particles, excited states, radical formation and their reactions are discussed. Behaviour of certain hydrocarbon classes: alkanes, cyclic hydrocarbons, olefines, aromatic hydrocarbons as well as different hydrocarbon mixtures is considered in detail. Radiation-chemical changes in organic coolants and ways of increasing radiation resistance are considered. Polyphenyl compounds are noted to be most perspective here

  9. Decomposition of PCBs in oils using gamma radiolysis

    International Nuclear Information System (INIS)

    Mincher, B.J.; Arbon, R.E.; Schwendiman, G.L.

    1996-01-01

    This paper investigates the radiolysis of the polychlorinated biphenyls (PCBs) in several oil matrices. The results of mechanism and kinetic studies in isooctane are presented. The decomposition of PCBs in isooctane is shown to occur by reductive dechlorination due to electron capture and to proceed with pseudo-first-order kinetics. The rate is dependent on the initial PCB concentration. Electron capture detection gas chromatograms confirm that dechlorination also occurs with commercial Aroclor PCBs in irradiated transformer and hydraulic oils. The results of a demonstration experiment involving PCB contaminated waste hydraulic oils are presented

  10. Study of the radiolysis of some simple alcohols

    International Nuclear Information System (INIS)

    Roux, Jean-Claude

    1974-01-01

    In the first part of this research thesis, the author recalls optical properties of electrons solvated in alcohols, and the various hypotheses of description of the mechanism of electron solvation in these polar environments. In the next parts, the author reports the study of reduced and oxidized species, presents a new model to explain the formation of aldehydes during the radiolysis of primary alcohols. He notices that this mode of formation does not comply with diffusion models. The FORTRAN software used for diffusion kinetic calculations, and experimental techniques are presented in appendix [fr

  11. Gamma radiolysis of C6F6, product formation

    International Nuclear Information System (INIS)

    Sagert, N.H.; LeBlanc, J.C.; Wood, D.D.; Kremers, W.; Westmore, J.B.; Buchannon, W.D.

    1991-01-01

    The γ radiolysis of perfluorobenzene (PFB) has been studied at a dose rate of about 26 Gy·s -1 and at total doses up to 10 5 Gy. Radiolyses were carried out in fluorine-passivated nickel cells in the absence of air. There were no significant gas yields, but higher molecular weight products were observed and characterized by combined gas chromatography and mass spectrometry (GC/MS). The yield of all polymers totalled 1.7 molecules of PFB consumed for each 100 eV absorbed. This result is comparable to yields measured by earlier workers at much higher doses and dose rates. (author)

  12. Pulse radiolysis apparatus for monitoring at 2000 Å

    DEFF Research Database (Denmark)

    Christensen, H.C.; Nilsson, G.; Pagsberg, Palle Bjørn

    1969-01-01

    A pulse radiolysis apparatus with photometric monitoring has been built around an 11 MeV, 250 mA peak current, linac that delivers single 0.25 to 4 μsec pulses. The novel features of the apparatus include (1) a 450 W xenon lamp as the analyzing light source which in pulsed operation had a 25 times...... increased luminance; (2) a fast electronic switch that cut out the signal due to the Cerenkov radiation; (3) a secondary emission chamber that allowed the simultaneous measurement of the current and the direction of the pulsed electron beam; and (4) a system for remote controlled change of liquid samples...

  13. Subpicosecond pulse radiolysis in liquid methyl-substituted benzene derivatives

    International Nuclear Information System (INIS)

    Okamoto, Kazumasa; Kozawa, Takahiro; Saeki, Akinori; Yoshida, Yoichi; Tagawa, Seiichi

    2007-01-01

    The early processes of radiation chemistry in the picosecond time region in methyl-substituted benzene derivatives have been investigated using subpicosecond pulse radiolysis. In o-xylene, a fairly slow geminate ion recombination was observed within 50 ps after the electron beam irradiation; this is due to the smaller electron mobility. The kinetic traces were analyzed using the Smoluchowski equation with exponential and modified-Gaussian (YGP) functions as the distribution of thermalized electrons. Only exponential functions well reproduced the experimental data within 50 ps after the electron pulse

  14. Programming for controlling of pulse radiolysis setup. Program RADIO96

    International Nuclear Information System (INIS)

    Mirkowski, J.; Grodkowski, J.

    1998-01-01

    Program RADIO96 was written in Pascal using DELPHI 1.0 (Borland) programming platform. It can operate on IBM PC compatible computers in WINDOWS 3x or WINDOWS'95 environment. The program is dedicated to the pulse radiolysis setup based on the linear electron accelerator LAE 13/9 of the Department of Radiation Chemistry and Technology of the INCT. This work was based on apparatus and results described before and also on programming manuals of used equipment and technical data of programming platform. (author)

  15. Set-up for pulse radiolysis of agressive substances

    International Nuclear Information System (INIS)

    Kozlowska-Milner, E.; Broszkiewicz, R.; Stanikowski, J.

    1975-01-01

    A set-up for the pulse radiolysis of aggressive substances with a relatively low consumption of the liquid, tested for anhydrous HNO 3 , has been described. The samples have been irradiated with single pulses of 10 MeV electrons at the linear accelerator type LAE 13-9. The absorption spectra of the irradiated samples (within a range of 300-800 nm) were provided by a xenon lamp. The variations of the voltage from the photomultiplier, coupled with an oscilloscope, were registered with the aid of a Polaroid camera. (T.G.)

  16. One-electron oxidations of ferrocenes: a pulse radiolysis study

    International Nuclear Information System (INIS)

    Faraggi, Moshe; Weinraub, Dany; Broitman, Federico; DeFelippis, M.R.; Klapper, M.H.

    1988-01-01

    Using the pulse radiolysis technique we have studied the oxidation by various inorganic radicals of four water soluble ferrocene derivatives, hydroxyethyl, dimethylaminomethyl, monocarboxylic acid and dicarboxylic acid. We report the second order rate constants for these reactions, the stabilities and spectral properties of the ferrocinium products, and the electrochemically determined ferrocinium/ferrocene redox potentials. We also present preliminary estimates of tyrosine and tryptophan radical redox potentials obtained with the dicarboxylic acid ferrocene derivative as reference, and we discuss the relationship between redox potential differences and the reactivities of the ferrocenes with the inorganic radicals. (author)

  17. Pulse radiolysis of catalase in solution: Pt. 1

    International Nuclear Information System (INIS)

    Gebicka, Lidia; Metodiewa, Diana; Gebicki, J.L.

    1989-01-01

    The time-course of absorption changes of oxygen-saturated solutions of bovine-liver catalase after pulse radiolysis have been studied. The rate constant of formation of Compound I due to the reaction of catalase with hydrogen peroxide has been estimated to be 2.0 x 10 7 dm 3 mol -1 s -1 . Radiation generated super-oxide radicals reduce Compound I to Compound II with a rate constant of 5.0 x 10 6 dm 3 mol -1 s -1 . The formation of Compound III in the direct reaction of O 2 - with catalase has also been observed. (author)

  18. Energy transfer from an alkene triplet state during pulse radiolysis

    International Nuclear Information System (INIS)

    Barwise, A.J.G.; Gorman, A.A.; Rodgers, M.A.J.

    1976-01-01

    Pulse radiolysis of a benzene solution of norbornene containing low concentrations of anthracene results in delayed formation of anthracene triplet: this is the result of diffusion-controlled energy transfer from the alkene triplet state which has a natural lifetime in benzene of 250 ns. The use of various hydrocarbon acceptors has indicated that Esub(T)=20 000+-500 cm -1 for the relaxed T 1 state of the alkene, at least 5000 cm -1 below that of the spectroscopic state. (Auth.)

  19. The application of N,N-dimethylhydroxylamine as reductant for the separation of plutonium from uranium

    International Nuclear Information System (INIS)

    Jinping Liu; Hui He; Hongbin Tang; Yanxin Chen

    2011-01-01

    Both single stage and multi-stages experiments on stripping plutonium with N,N-dimethylhydroxylamine (DMHAN) as reductant with methylhydrozine (MMH) as supporting reductant were carried out. The effect of contact time, temperature, acidity, concentration of DMHAN on back-extraction rate of plutonium was investigated in the single stage experiment. The results demonstrated that the reaction of stripping Pu(IV) in the organic phase (30% TBP-kerosene) 1BF solutions by DMHAN exhibits excellent stripping efficiency. Under the given conditions, the back-extraction rate of plutonium reaches 90% within 2 min. Higher temperature, lower acidity and the increased concentration of DMHAN benefit the stripping reaction. The concentration profile of HNO 3 , uranium and plutonium were determined in a multi-stages mixer-settler after the steady state of the back-extraction, and the multi-stages results show that the plutonium can be separated effectively from uranium. The recovery of plutonium and uranium reach 99.995% or over 99.99% respectively. The separation factor of U from Pu (SF Pu/U ) is about 2 x 10 4 . (author)

  20. Long time contamination from plutonium

    International Nuclear Information System (INIS)

    Fueloep, M.; Patzeltova, N.; Ragan, P.; Matel, L.

    1995-01-01

    Plutonium isotopes in the organism of the patient (who had participated in the liquidation works after the Chernobyl accident; for three month he had stayed in the epicenter, where he acted as a chauffeur driving a radioactive material to the place of destination) from urine were determined. For determination of the concentration of Pu-239, Pu-240 in urine a modified radiochemical method was used. After mineralization the sample was separated as an anion-nitrate complex with contact by the anion form of the resin in the column. The resin was washed by 8 M HNO 3 , the 8 M HCl with 0.3 M HNO 3 for removing the other radionuclides. The solution 0.36 M HCl with 0.01 M HF was used for the elution of plutonium. Using the lanthanum fluoride technique the sample was filtrated through a membrane filter. The plutonium was detected in the dry sample. The Pu-239 tracer was used for the evaluation of the plutonium separation efficiency. The alpha spectrometric measurements were carried out with a large area silicon detector. The samples were measured and evaluated in the energy region 4.98-5.18 MeV. The detection limit of alpha spectrometry measurements has been 0.01 Bq dm -3 . The concentration of plutonium in the 24-hour urine was determined three times in the quarter year intervals. The results are: 54 mBq, 63.2 mBq, 53 mBq, with average 56,7 mBq. From the results of the analyses of plutonium depositions calculated according to ICRP 54 the intake of this radionuclide for the patient was 56.7 kBq. To estimate a committed effective dose (50 years) from the intake of plutonium was used a conversion factor 6.8.10 -5 Sv.Bq -1 (class W). So the expressed committed effective dose received from the plutonium intake is 3.8 Sv. This number is relatively high and all the effective dose will be higher, because the patient was exposed to the other radionuclides too. For example the determination of the rate radionuclides Am-241/Pu-239,Pu-240 was 32-36 % in the fallout after the Chernobyl

  1. Collector for recovering gallium from weapons plutonium

    International Nuclear Information System (INIS)

    Philip, C.V.; Anthony, R.G.; Chokkaram, S.

    1998-09-01

    Currently, the separation of gallium from weapons plutonium involves the use of aqueous processing using either solvent extraction of ion exchange. However, this process generates significant quantities of liquid radioactive wastes. A Thermally Induced Gallium Removal process, or TIGR, developed by researchers at Los Alamos National Laboratories, is a simpler alternative to aqueous processing. This research examined this process, and the behavior of gallium suboxide, a vapor that is swept away by passing hydrogen/argon over gallium trioxide/plutonium oxide heated at 1100 C during the TIGR process. Through experimental procedures, efforts were made to prevent the deposition of corrosive gallium onto furnace and vent surfaces. Experimental procedures included three options for gallium removal and collection: (1) collection of gallium suboxide through use of a cold finger; (2) collection by in situ air oxidation; and (3) collection of gallium on copper. Results conclude all three collection mechanisms are feasible. In addition, gallium trioxide exists in three crystalline forms, and each form was encountered during each experiment, and that each form will have a different reactivity

  2. Method of processing plutonium and uranium solution

    International Nuclear Information System (INIS)

    Otsuka, Katsuyuki; Kondo, Isao; Suzuki, Toru.

    1989-01-01

    Solutions of plutonium nitrate solutions and uranyl nitrate recovered in the solvent extraction step in reprocessing plants and nuclear fuel production plants are applied with low temperature treatment by means of freeze-drying under vacuum into residues containing nitrates, which are denitrated under heating and calcined under reduction into powders. That is, since complicate processes of heating, concentration and dinitration conducted so far for the plutonium solution and uranyl solution are replaced with one step of freeze-drying under vacuum, the process can be simplified significantly. In addition, since the treatment is applied at low temperature, occurrence of corrosion for the material of evaporation, etc. can be prevented. Further, the number of operators can be saved by dividing the operations into recovery of solidification products, supply and sintering of the solutions and vacuum sublimation. Further, since nitrates processed at a low temperature are powderized by heating dinitration, the powderization step can be simplified. The specific surface area and the grain size distribution of the powder is made appropriate and it is possible to obtain oxide powders of physical property easily to be prepared into pellets. (N.H.)

  3. Double shell tanks plutonium inventory assessment

    International Nuclear Information System (INIS)

    Tusler, L.A.

    1995-01-01

    This report provides an evaluation that establishes plutonium inventory estimates for all DSTs based on known tank history information, the DST plutonium inventory tracking system, tank characterization measurements, tank transfer records, and estimated average concentration values for the various types of waste. These estimates use data through December 31, 1994, and give plutonium estimates as of January 1, 1995. The plutonium inventory values for the DSTs are given in Section 31. The plutonium inventory estimate is 224 kg for the DSTs and 854 kg for the SSTs for a total of 1078 kg. This value compares favorably with the total plutonium inventory value of 981 kg obtained from the total plutonium production minus plutonium recovery analysis estimates

  4. Oxidation-state maxima in plutonium chemistry

    International Nuclear Information System (INIS)

    Silver, G.L.

    2013-01-01

    Maxima in the fractions of the trivalent and hexavalent oxidation states of plutonium are inherent in the algebra of its disproportionation reactions. The maxima do not support overall disproportionation equations as satisfactory representations of aqueous plutonium. (author)

  5. Recovery studies for plutonium machining oil coolant

    International Nuclear Information System (INIS)

    Navratil, J.D.; Baldwin, C.E.

    1977-01-01

    Lathe coolant oil, contaminated with plutonium and having a carbon tetrachloride diluent, is generated in plutonium machining areas at Rocky Flats. A research program was initiated to determine the nature of plutonium in this mixture of oil and carbon tetrachloride. Appropriate methods then could be developed to remove the plutonium and to recycle the oil and carbon tetrachloride. Studies showed that the mixtures of spent oil and carbon tetrachloride contained particulate plutonium and plutonium species that are soluble in water or in oil and carbon tetrachloride. The particulate plutonium was removed by filtration; the nonfilterable plutonium was removed by adsorption on various materials. Laboratory-scale tests indicated the lathe-coolant oil mixture could be separated by distilling the carbon tetrachloride to yield recyclable products

  6. Plutonium and americium separation from salts

    International Nuclear Information System (INIS)

    Hagan, P.G.; Miner, F.J.

    1976-01-01

    Salts or materials containing plutonium and americium are dissolved in hydrochloric acid, heated, and contacted with an alkali metal carbonate solution to precipitate plutonium and americium carbonates which are thereafter readily separable from the solution

  7. Plutonium-238 and plutonium-239 metabolism in dairy cows following ingestion of mixed oxides

    International Nuclear Information System (INIS)

    Patzer, R.G.; Mullen, A.A.; Sutton, W.W.; Potter, G.D.; Mosley, R.E.; Efurd, D.W.; Stalnaker, N.D.

    1985-01-01

    Dairy cows were given oral dosage of plutonium-238 and plutonium-239 dioxide particles in a study to determine the relative gastrointestinal absorption and tissue distribution of the nuclides. Two cows were given particles in which the two isotopes were homogeneously mixed within the particles. A third cow was given two batches of particles which contained either plutonium-238 or plutonium-239. Results indicate that, when the two isotopes of plutonium are homogeneous within the particles, there is no difference between plutonium-238 and plutonium-239 in the relative gastrointestinal absorption and tissue distribution

  8. Plutonium Disposition Now exclamation point

    International Nuclear Information System (INIS)

    Buckner, M.R.

    1995-01-01

    A means for use of existing processing facilities and reactors for plutonium disposition is described which requires a minimum capital investment and allows rapid implementation. The scenario includes interim storage and processing under IAEA control, and fabrication into MOX fuel in existing or planned facilities in Europe for use in operating reactors in the two home countries. Conceptual studies indicate that existing Westinghouse four-loop designs can safety dispose of 0.94 MT of plutonium per calendar year. Thus, it would be possible to consume the expected US excess stockpile of about 50 MT in two to three units of this type, and it is highly likely that a comparable amount of the FSU excess plutonium could be deposed of in a few VVER-1000's. The only major capital project for this mode of plutonium disposition would be the weapons-grade plutonium processing which could be done in a dedicated international facility or using existing facilities in the US and FSU under IAEA control. This option offers the potential for quick implementation at a very low cost to the governments of the two countries

  9. Fuel cycles using adulterated plutonium

    International Nuclear Information System (INIS)

    Brooksbank, R.E.; Bigelow, J.E.; Campbell, D.O.; Kitts, F.G.; Lindauer, R.B.

    1978-01-01

    Adjustments in the U-Pu fuel cycle necessitated by decisions made to improve the nonproliferation objectives of the US are examined. The uranium-based fuel cycle, using bred plutonium to provide the fissile enrichment, is the fuel system with the highest degree of commercial development at the present time. However, because purified plutonium can be used in weapons, this fuel cycle is potentially vulnerable to diversion of that plutonium. It does appear that there are technologically sound ways in which the plutonium might be adulterated by admixture with 238 U and/or radioisotopes, and maintained in that state throughout the fuel cycle, so that the likelihood of a successful diversion is small. Adulteration of the plutonium in this manner would have relatively little effect on the operations of existing or planned reactors. Studies now in progress should show within a year or two whether the less expensive coprocessing scheme would provide adequate protection (coupled perhaps with elaborate conventional safeguards procedures) or if the more expensive spiked fuel cycle is needed as in the proposed civex pocess. If the latter is the case, it will be further necessary to determine the optimum spiking level, which could vary as much as a factor of a billion. A very basic question hangs on these determinations: What is to be the nature of the recycle fuel fabrication facilities. If the hot, fully remote fuel fabrication is required, then a great deal of further development work will be required to make the full cycle fully commercial

  10. Selecting a plutonium vitrification process

    Energy Technology Data Exchange (ETDEWEB)

    Jouan, A. [Centre d`Etudes de la Vallee du Rhone, Bagnols sur Ceze (France)

    1996-05-01

    Vitrification of plutonium is one means of mitigating its potential danger. This option is technically feasible, even if it is not the solution advocated in France. Two situations are possible, depending on whether or not the glass matrix also contains fission products; concentrations of up to 15% should be achievable for plutonium alone, whereas the upper limit is 3% in the presence of fission products. The French continuous vitrification process appears to be particularly suitable for plutonium vitrification: its capacity is compatible with the required throughout, and the compact dimensions of the process equipment prevent a criticality hazard. Preprocessing of plutonium metal, to convert it to PuO{sub 2} or to a nitric acid solution, may prove advantageous or even necessary depending on whether a dry or wet process is adopted. The process may involve a single step (vitrification of Pu or PuO{sub 2} mixed with glass frit) or may include a prior calcination step - notably if the plutonium is to be incorporated into a fission product glass. It is important to weigh the advantages and drawbacks of all the possible options in terms of feasibility, safety and cost-effectiveness.

  11. Plutonium in depleted uranium penetrators

    International Nuclear Information System (INIS)

    McLaughlin, J.P.; Leon-Vintro, L.; Smith, K.; Mitchell, P.I.; Zunic, Z.S.

    2002-01-01

    Depleted Uranium (DU) penetrators used in the recent Balkan conflicts have been found to be contaminated with trace amounts of transuranic materials such as plutonium. This contamination is usually a consequence of DU fabrication being carried out in facilities also using uranium recycled from spent military and civilian nuclear reactor fuel. Specific activities of 239+240 Plutonium generally in the range 1 to 12 Bq/kg have been found to be present in DU penetrators recovered from the attack sites of the 1999 NATO bombardment of Kosovo. A DU penetrator recovered from a May 1999 attack site at Bratoselce in southern Serbia and analysed by University College Dublin was found to contain 43.7 +/- 1.9 Bq/kg of 239+240 Plutonium. This analysis is described. An account is also given of the general population radiation dose implications arising from both the DU itself and from the presence of plutonium in the penetrators. According to current dosimetric models, in all scenarios considered likely ,the dose from the plutonium is estimated to be much smaller than that due to the uranium isotopes present in the penetrators. (author)

  12. A World made of Plutonium?

    International Nuclear Information System (INIS)

    Broda, E.

    1976-01-01

    This lecture by Engelbert Broda was written for the 26th Pugwash Conference in Mühlhausen, Germany, 26 – 31 August 1976: Public doubts about nuclear energy are generally directed at the problems of routine emissions of radionuclides, of catastrophic accidents, and of terminal waste disposal. Curiously, the most important problem is not being given sufficient attention: The use of plutonium from civilian reactors fpr weapons production. According to current ideas about a nuclear future, 5000 tons (order of magnitude) of plutonium are to be made annually by year 2000, and about 10 000 tons will all the time be in circulation (transport, reprocessing, reproduction of fuel elements, etc.). It is a misconception that plutonium from power reactors is unsuitable as a nuclear explosive. 5000 tons are enough for several hundred thousand (!) of bombs, Nagasaki type. By the year 2000 maybe 40 – 50 countries will have home-made plutonium. Plutonium production and proliferation are the most serious problems in a nuclear world. (author)

  13. Plutonium determination by isotope dilution

    International Nuclear Information System (INIS)

    Lucas, M.

    1980-01-01

    The principle is to add to a known amount of the analysed solution a known amount of a spike solution consisting of plutonium 242. The isotopic composition of the resulting mixture is then determined by surface ionization mass spectrometry, and the plutonium concentration in the solution is deduced, from this measurement. For irradiated fuels neutronic studies or for fissile materials balance measurements, requiring the knowledge of the ratio U/Pu or of concentration both uranium and plutonium, it is better to use the double spike isotope dilution method, with a spike solution of known 233 U- 242 Pu ratio. Using this method, the ratio of uranium to plutonium concentration in the irradiated fuel solution can be determined without any accurate measurement of the mixed amounts of sample and spike solutions. For fissile material balance measurements, the uranium concentration is determined by using single isotope dilution, and the plutonium concentration is deduced from the ratio Pu/U and U concentration. The main advantages of isotope dilution are its selectivity, accuracy and very high sensitivity. The recent improvements made to surface ionization mass spectrometers have considerably increased the precision of the measurements; a relative precision of about 0.2% to 0.3% is obtained currently, but it could be reduced to 0.1%, in the future, with a careful control of the experimental procedures. The detection limite is around 0.1 ppb [fr

  14. Plutonium Proliferation: The Achilles Heel of Disarmament

    International Nuclear Information System (INIS)

    Leventhal, Paul

    2001-01-01

    Plutonium is a byproduct of nuclear fission, and it is produced at the rate of about 70 metric tons a year in the world's nuclear power reactors. Concerns about civilian plutonium ran high in the 1970s and prompted enactment of the Nuclear Non-Proliferation Act of 1978 to give the United States a veto over separating plutonium from U.S.-supplied uranium fuel. Over the years, however, so-called reactor-grade plutonium has become the orphan issue of nuclear non-proliferation, largely as a consequence of pressures from plutonium-separating countries. The demise of the fast breeder reactor and the reluctance of utilities to introduce plutonium fuel in light-water reactors have resulted in large surpluses of civilian, weapons-usable plutonium, which now approach in size the 250 tons of military plutonium in the world. Yet reprocessing of spent fuel for recovery and use of plutonium proceeds apace outside the United States and threatens to overwhelm safeguards and security measures for keeping this material out of the hands of nations and terrorists for weapons. A number of historical and current developments are reviewed to demonstrate that plutonium commerce is undercutting efforts both to stop the spread of nuclear weapons and to work toward eliminating existing nuclear arsenals. These developments include the breakdown of U.S. anti-plutonium policy, the production of nuclear weapons by India with Atoms-for-Peace plutonium, the U.S.-Russian plan to introduce excess military plutonium as fuel in civilian power reactors, the failure to include civilian plutonium and bomb-grade uranium in the proposed Fissile Material Cutoff Treaty, and the perception of emerging proliferation threats as the rationale for development of a ballistic missile defense system. Finally, immobilization of separated plutonium in high-level waste is explored as a proliferation-resistant and disarmament-friendly solution for eliminating excess stocks of civilian and military plutonium.

  15. HB-Line Plutonium Oxide Data Collection Strategy

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, R. [Savannah River Nuclear Solutions; Varble, J. [Savannah River Nuclear Solutions; Jordan, J. [Savannah River Nuclear Solutions

    2015-05-26

    identifies the required facility procedures, DCS print outs, and laboratory results needed to assemble a final data package for each HB-Line plutonium oxide interim oxide can. The data traveler may identify the specific values (data) required to be extracted from the collected facility procedures and DCS print outs. The data traveler may also identify associated criteria to be checked. Inevitably there will be procedure anomalies during the course of the HB-Line plutonium oxide campaign that will have to be addressed in a timely manner.

  16. Plutonium separation and the measurement of its concentration in natural waters (1963); Separation du plutonium et mesure de sa concentration dans les eaux naturelles

    Energy Technology Data Exchange (ETDEWEB)

    Scheidhauer, J; Messainguiral, L; Meiraneisio, A M [Commissariat a l' Energie Atomique, Centre de Production de Plutonium, Marcoule (France). Centre d' Etudes Nucleaires

    1963-07-01

    After concentration by chemisorption on a calcium fluoride suspension, the plutonium is purified and isolated by xylene extraction of the complex formed with T.T.A. The radioelement is measured by counting with a ZnS (Ag) scintillator after evaporation or electrolysis. (authors) [French] Apres concentration par chimisorption sur une suspension de fluorure de calcium, le plutonium est purifie et isole par extraction au xylene du complexe forme avec la T.T.A. La mesure du radioelement est effectuee par comptage au scintillateur S Zn (Ag) apres evaporation ou electrolyse. (auteurs)

  17. Reactivity of OH radicals with chlorobenzoic acids-A pulse radiolysis and steady-state radiolysis study

    DEFF Research Database (Denmark)

    Zona, Robert; Solar, Sonja; Getoff, Nikola

    2010-01-01

    The reactions of OH radicals with 2-, 3-, 4-chlorobenzoic acids (ClBzA) and chlorobenzene (ClBz), k(OH+substrates)=(4.5−6.2)×109 dm3 mol−1 s−1, have been studied by pulse radiolysis in N2O saturated solutions. The absorption maxima of the OH-adducts were in the range of 320−340 nm. Their decay wa...... to degradation. The order for the efficiency of dehalogenation was 4->2->3-ClBzA. Several primary radiolytic products could be detected by HPLC. To evaluate the toxicity of final products a bacterial bioluminescence test was carried out....

  18. Plutonium Oxide Process Capability Work Plan

    Energy Technology Data Exchange (ETDEWEB)

    Meier, David E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tingey, Joel M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-02-28

    Pacific Northwest National Laboratory (PNNL) has been tasked to develop a Pilot-scale Plutonium-oxide Processing Unit (P3U) providing a flexible capability to produce 200g (Pu basis) samples of plutonium oxide using different chemical processes for use in identifying and validating nuclear forensics signatures associated with plutonium production. Materials produced can also be used as exercise and reference materials.

  19. Civil plutonium amounts in the world

    International Nuclear Information System (INIS)

    Naudet, G.

    1994-01-01

    The experience of plutonium reprocessing in water reactors is positive and today the use of this nuclear fuel is at industrial level. Plutonium quantities in spent fuel go on increasing, plutonium stock coming from reprocessing can be controlled: according to conjuncture, it will evolve by stabilization or decreasing at the beginning of next century

  20. The use of calorimetry for plutonium assay

    International Nuclear Information System (INIS)

    Mason, J.A.

    1982-12-01

    Calorimetry is a technique for measuring the thermal power of heat-producing substances. The technique may be applied to the measurement of plutonium-bearing materials which evolve heat as a result of alpha and beta decay. A calorimetric measurement of the thermal power of a plutonium sample, combined with a knowledge or measurement of the plutonium isotopic mass ratios of the sample provides a convenient and accurate, non-destructive measure of the total plutonium mass of the sample. The present report provides a description, and an assessment of the calorimetry technique applied to the assay of plutonium-bearing materials. Types and characteristics of plutonium calorimeters are considered, as well as calibration and operating procedures. The instrumentation used with plutonium calorimeters is described and the use of computer control for calorimeter automation is discussed. A critical review and assessment of plutonium calorimetry literature since 1970 is presented. Both fuel element and plutonium-bearing material calorimeters are considered. The different types of plutonium calorimeters are evaluated and their relative merits are discussed. A combined calorimeter and gamma-ray measurement assay system is considered. The design principles of plutonium assay calorimeters are considered. An automatic, computer-based calorimeter control system is proposed in conjunction with a general plutonium assay calorimeter design. (author)

  1. Tabulated Neutron Emission Rates for Plutonium Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Shores, Erik Frederick [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-07-24

    This work tabulates neutron emission rates for 80 plutonium oxide samples as reported in the literature. Plutonium-­238 and plutonium-­239 oxides are included and such emission rates are useful for scaling tallies from Monte Carlo simulations and estimating dose rates for health physics applications.

  2. Possible combustion hazards in 3013 plutonium waste container

    International Nuclear Information System (INIS)

    Sherman, M.P.

    1999-01-01

    Are there combustion hazards in plutonium-contaminated waste containers caused by combustible gas generation? Current gas generation models in which the only reaction considered is radiolysis must inevitably predict eventual complete dissociation of any water present into hydrogen and oxygen. Waste prepared for the 3013 container should be less subject to this problem because organic material and most of the absorbed water should have been removed. Depending on the waste form, moisture content, organic content, temperature, and container material, the pressure rise due to gas generation will be bounded by backreactions, recombination of the hydrogen and oxygen, absorption of the oxygen by plutonium oxide, and possibly other chemical reactions. Examination of a variety of food pack waste containers at Los Alamos National Laboratory (LANL) has shown little pressure rise, indeed often subatmospheric pressures. In a few cases large hydrogen concentrations up to 47% mole fraction were observed, but with negligible oxygen content. The only fuel seen in significant quantities was H 2 and, in one case, CO; the only oxidizer seen in significant quantities was O 2 . Considerable work on measuring gas generation is being done at Westinghouse Savannah River Company and LANL. In a mixture of H 2 , O 2 , and other diluent gases, if the hydrogen concentration is below the value at the lean flammability limit, or if the oxygen concentration is below that at the rich flammability limit, a flame will not propagate from an ignition source. Assuming H 2 is the only fuel present in significant quantities, a mixture leaner than the lean limit will get only leaner if mixed with air and is therefore no combustion hazard. However, when a mixture containing large amounts of H 2 is nonflammable because there is insufficient O 2 , there is a hazard. If the mixture should leak into a volume containing O 2 , or the container is opened into the surrounding air, the mixture will pass through the

  3. Preventing pollution from plutonium processing

    International Nuclear Information System (INIS)

    Pillay, K.K.S.

    1993-01-01

    The plutonium processing facility at Los Alamos has adopted the strategic goal of becoming a facility that processes plutonium in a way that produces only environmentally benign waste streams. Pollution prevention through source reduction and environmentally sound recycling are being pursued. General approaches to waste reductions are administrative controls, modification of process technologies, and additional waste polishing. Recycling of waste materials, such as spent acids and salts, are technical possibilities and are being pursued to accomplish additional waste reduction. Liquid waste stream polishing to remove final traces of plutonium and hazardous chemical constituents is accomplished through (a) process modifications, (b) use of alternative chemicals and sorbents for residue removal, (c) acid recycling, and (d) judicious use of a variety of waste polishing technologies. Technologies that show promise in waste minimization and pollution prevention are identified. Working toward this goal of pollution prevention is a worthwhile endeavor, not only for Los Alamos, but for the Nuclear Complex of the future

  4. Technological alternatives for plutonium storage

    International Nuclear Information System (INIS)

    1978-12-01

    This paper discusses the problems of large long term storage since stores at fabrication plants may depend on the form of plutonium ultimately chosen for transport. The paper's conclusion includes: MOX can be regarded as more proliferation resistant than PUO 2 but no experience of long term storage is available, therefore further R and D is required; co-location of the store with reprocessing plants (and fuel fabrication plant) would appear to have advantages in non-proliferation, safeguards implementation, environmental protection and economic aspects; there are strong non-proliferation and security arguments for not moving plutonium away from the site where it was separated until there is an identifiable and scheduled end use. The design of the store, the form in which plutonium should be stored, particularly as MOX, and the costs and further R and D required are considered. The possible location of stores is also discussed and institutional questions briefly considered

  5. Plutonium and U-233 mines

    International Nuclear Information System (INIS)

    Milgram, M.S.

    1983-08-01

    A comparison is made among second generation reactor systems fuelled primarily with fissile plutonium and/or U-233 in uranium or thorium. This material is obtained from irradiated fuel from first generation CANDU reactors fuelled by natural or enriched uranium and thorium. Except for plutonium-thorium reactors, second generation reactors demand similar amounts of reprocessing throughput, but the most efficient plutonium burning systems require a large prior allocation of uranium. Second generation reactors fuelled by U-233 make more efficient use of resources and lead to more flexible fuelling strategies, but require development of first generation once-through thorium cycles and early demonstration of the commercial viability of thorium fuel reprocessing. No early implementation of reprocessing technology is required for these cycles

  6. Political influences in plutonium recycling

    International Nuclear Information System (INIS)

    Patak, H.N.

    1982-01-01

    The history of plutonium safeguards is one of political error and misunderstandings, as well as a lack of technical knowledge. Although there was widespread support for preventing the proliferation of nuclear explosives, with over 100 nations signing the Nonproliferation Treaty of 1969, India's 1974 nuclear test brought renewed political activity to prevent another such occurrence. Opposition has been directed only at how to pursue this goal, but the status of four major experiments aimed at minimizing weapons proliferation is one of failure, intensified by a weakening of the International Atomic Energy Agency (IAEA). If the link between plutonium power and weapons production can be broken through on-site reprocessing, the situation could improve. One course would be for the nuclear power industry to adopt its own system for safe guarding plutonium

  7. Plutonium and latent nuclear proliferation

    International Nuclear Information System (INIS)

    Quester, G.H.

    1992-01-01

    A country producing nuclear electric power acquires an ability to produce atomic bombs quite easily and without taking many steps beyond that which would be perfectly normal for civilian purposes. The role of plutonium in the three fold list of the gains that must be sought in arms control formulated by Schelling and Halpevin are discussed. On the first, that we should seek to reduce the likelihood of war, it can be argued that plutonium reduces the likelihood in some cases. The second, that we should seek to reduce the destruction in war, is made worse by plutonium. On the third criterion, that we should seek to reduce the burdens in peacetime of everyone's being prepared for war, the situation is confusing and depends on the prospects for nuclear electrical power. It is concluded that latent capability to produce nuclear weapons may be sufficient without the need for actual detonations and deployment of bombs. (UK)

  8. Plutonium accident resistant container project

    International Nuclear Information System (INIS)

    Andersen, J.A.

    1978-09-01

    The PARC (plutonium accident resistant container) project resulted in the design, development, and certification testing of a crashworthy air-transportable plutonium package (shipping container) for certification by the USNRC (Nuclear Regulatory Commission). This PAT-1 (plutonium air transportable) package survives a very severe sequential test program of impact, crush, puncture, slash, burn, and water immersion. There is also an individual hydrostatic pressure test. The package has a payload mass capacity of 2 kg of PuO 2 and a thermal capacity of 25 watts. The design rationale for very high energy absorption (impact, crush, puncture, and slash protection) with residual high-level fire protection, resulted in a reasonably small air-transportable package, advancing the packaging state-of-art. Optimization design iterations were utilized in the areas of impact energy absorption and stress and thermal analysis. Package test results are presented in relation to radioactive materials containment acceptance criteria, shielding and criticality standards

  9. Plutonium accident resistant container project

    International Nuclear Information System (INIS)

    Andersen, J.A.

    1978-05-01

    The PARC (plutonium accident resistant container) project resulted in the design, development, and certification testing of a crashworthy air-transportable plutonium package (shipping container) for certification by the USNRC. This PAT-1 (plutonium air transportable) package survives a very severe sequential test program of impact, crush, puncture, slash, burn, and water immersion. There is also an individual hydrostatic pressure test. The package has a payload mass capacity of 2 kg of PuO2 and a thermal capacity of 25 watts. The design rationale for very high energy absorption (impact, crush, puncture, and slash protection) with residual high-level fire protection, resulted in a reasonalby small air-transportable package, advancing the packaging state-of-art. Optimization design iterations were utilized in the areas of impact energy absorption and stress and thermal analysis. Package test results are presented in relation to radioactive materials containment acceptance criteria, shielding and criticality standards

  10. Shielding calculational system for plutonium

    International Nuclear Information System (INIS)

    Zimmerman, M.G.; Thomsen, D.H.

    1975-08-01

    A computer calculational system has been developed and assembled specifically for calculating dose rates in AEC plutonium fabrication facilities. The system consists of two computer codes and all nuclear data necessary for calculation of neutron and gamma dose rates from plutonium. The codes include the multigroup version of the Battelle Monte Carlo code for solution of general neutron and gamma shielding problems and the PUSHLD code for solution of shielding problems where low energy gamma and x-rays are important. The nuclear data consists of built in neutron and gamma yields and spectra for various plutonium compounds, an automatic calculation of age effects and all cross-sections commonly used. Experimental correlations have been performed to verify portions of the calculational system. (23 tables, 7 figs, 16 refs) (U.S.)

  11. Preventing pollution from plutonium processing

    International Nuclear Information System (INIS)

    Pillay, K.K.S.

    1995-01-01

    The plutonium processing facility at Los Alamos has adopted the strategic goal of becoming a facility that processes plutonium in a way that produces only environmentally benign waste streams. Pollution prevention through source reduction and environmentally sound recycling are being pursued. General approaches to waste reductions are administrative controls, modification of process technologies, and additional waste polishing. Recycling of waste materials, such as spent acids and salts, are technical possibilities and are being pursued to accomplish additional waste reduction. Liquid waste stream polishing to remove final traces of plutonium and hazardous chemical constituents is accomplished through process modifications, use of alternative chemicals and sorbents for residue removal, acid recycling, and judicious use of a variety of waste polishing technologies. Technologies that show promise in waste minimization and pollution prevention are identified. Working toward this goal of pollution prevention is a worthwhile endeavor , not only for Los Alamos, but for the Nuclear Complex of the future. (author) 12 refs.; 2 figs

  12. Safeguarding the Plutonium Fuel Cycle

    International Nuclear Information System (INIS)

    Johnson, S.J.; Lockwood, D.

    2013-01-01

    In developing a Safeguards Approach for a plutonium process facility, two general diversion and misuse scenarios must be addressed: 1) Unreported batches of undeclared nuclear material being processed through the plant and bypassing the accountancy measurement points, and 2) The operator removing plutonium at a rate that cannot be detected with confidence due to measurement uncertainties. This paper will look at the implementation of international safeguards at plutonium fuel cycle facilities in light of past lessons learned and current safeguards approaches. It will then discuss technical areas which are currently being addressed as future tools to improve on the efficiency of safeguards implementation, while maintaining its effectiveness. The discussion of new improvements will include: safeguards by design (SBD), process monitoring (PM), measurement and monitoring equipment, and data management. The paper is illustrated with the implementation of international safeguards at the Rokkasho Reprocessing Plant in Japan and its accountancy structure is detailed. The paper is followed by the slides of the presentation

  13. Nukem's plutonium hitches a ride

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    The European repercussions of a scandal involving the illegal movement of plutonium and cobalt 60 in canisters in which it was claimed there was only low-level radioactive waste, from West Germany to the reprocessing centre at Mol, Belgium are considered. Large bribes were paid to employees of the nuclear industry and government inspectors to allow this illicit transport to carry on over a number of years. It is not yet clear where the plutonium came from or where it was going. The suggestion that it may have been sold to Libya or Pakistan for nuclear weapons is very damaging to the nuclear safety argument. Even if the plutonium was being disposed of because it could not be accounted for, the safeguard procedures do not give confidence to the European public more aware of nuclear safety than ever. (UK)

  14. Plutonium-238 Decision Analysis

    International Nuclear Information System (INIS)

    Brown, Mike; Lechel, David J.; Leigh, C.D.

    1999-01-01

    Five transuranic (TRU) waste sites in the Department of Energy (DOE) complex, collectively, have more than 2,100 cubic meters of Plutonium-238 (Pu-238) TRU waste that exceed the wattage restrictions of the Transuranic Package Transporter-II (TRUPACT-11). The Waste Isolation Pilot Plant (WIPP) is being developed by the DOE as a repository for TRU waste. With the Waste Isolation Pilot Plant (WIPP) opening in 1999, these sites are faced with a need to develop waste management practices that will enable the transportation of Pu-238 TRU waste to WIPP for disposal. This paper describes a decision analysis that provided a logical framework for addressing the Pu-238 TRU waste issue. The insights that can be gained by performing a formalized decision analysis are multifold. First and foremost, the very process. of formulating a decision tree forces the decision maker into structured, logical thinking where alternatives can be evaluated one against the other using a uniform set of criteria. In the process of developing the decision tree for transportation of Pu-238 TRU waste, several alternatives were eliminated and the logical order for decision making was discovered. Moreover, the key areas of uncertainty for proposed alternatives were identified and quantified. The decision analysis showed that the DOE can employ a combination approach where they will (1) use headspace gas analyses to show that a fraction of the Pu-238 TRU waste drums are no longer generating hydrogen gas and can be shipped to WIPP ''as-is'', (2) use drums and bags with advanced filter systems to repackage Pu-238 TRU waste drums that are still generating hydrogen, and (3) add hydrogen getter materials to the inner containment vessel of the TRUPACT-11to relieve the build-up of hydrogen gas during transportation of the Pu-238 TRU waste drums

  15. Plutonium hydrolysis and the double double-point

    International Nuclear Information System (INIS)

    Silver, G.L.

    2011-01-01

    There is uncertainty about the numerical value of the first hydrolysis constant of the tetravalent plutonium ion. A new method for discriminating between the claims is illustrated. It suggests the traditional estimates of that constant are closer to its true value than a singular result based on a few solvent-extraction experiments. A previously unnoticed multiple point in aqueous Pu chemistry is illustrated. (author)

  16. Free radicals generated by radiolysis of aqueous solutions

    International Nuclear Information System (INIS)

    Schwarz, H.A.

    1981-01-01

    The free radicals produced in the radiolysis of aqueous solutions span the range of redox potentials from -2.9 to +2.65 volts. The identity and nature of these radicals were discussed. Most of the discussion was results obtained with low LET radiation sources ( 60 Co gamma radiation or electron accelerators). Water radiolysis provides the synthesis of many radicals and radical ions in aqueous solution. The primary radicals, e/sub aq/ - H, OH, are well characterized. The radical population can be made to be 90% pure OH (or O - ) if N 2 O solutions are irradiated, the remaining 10% being H atoms. 55% of the radicals can be converted to H atoms in acid solution or in neutral phosphate solutions(e/sub aq/ - reacts with H 2 PO 4- to produce H). The remaining 45% (OH radicals) are difficult to convert to H by reaction with H 2 , due to the slow rate of the reaction. About 100 atmospheres of H 2 are required to do the conversion in less than 10 - 6 sec. 3 figures, 3 tables. (DP)

  17. Gamma-radiolysis of some glycoproteins in dilute aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Nagrani, S

    1981-01-01

    A study has been made of the radiation-induced damage of some glycoproteins in dilute aqueous solutions. By use of specific radical scavengers, the roles of the individual free radicals, formed by ..gamma..-radiolysis, in causing damage has been assessed. The most effective radical in causing damage to human and porcine glycopolypeptide is the OH radical. The structure of the different blood group glycopolypeptides determines the sensitivity towards the free radical attack. The glycopolypeptide shows depolymerization and a characteristic absorption at approximately 270 nm due to the formation of additional products on irradiation. Chemical changes of the irradiated glycopolypeptide solutions revealed significant damage to the oligosaccharide chain and the polypeptide core of the glycopolypeptide. The radiation-induced inactivation of another glycoprotein, external yeast invertase, due to different radical species at pH 7.0 decreases in the following order: ea-barq > OH radical > (SCN) radical/sub 2//sup -/ > Br radical/sub 2//sup -/. The structure of this enzyme, accounts for the mechanism of enzyme inactivation and the relative damage of carbohydrate and amino acid residues. The irradiated enzyme solutions show significant changes in their electrophoretic behaviour on cellogel electrophoresis due to the formation of radiolysis products, which also show characteristic absorption maxima at approximately 275 nm. (author).

  18. Radiolysis of cyanocobalamin (vitamin B{sub 12})

    Energy Technology Data Exchange (ETDEWEB)

    Juanchi, X.; Albarran, G.; Negron-Mendoza, A

    2000-03-01

    Research on the radiolysis of vitamins is of considerable interest since these compounds are important nutritional constituents in foods and in dietetic supplements. In spite of these considerations there are few data and very often difficult to compare for the radiolytic behavior of vitamins. In this work we focused our attention on to the study of the radiolysis of cyanocobalamin (vitamin B{sub 12}) in solid state and in aqueous solutions. The procedure was followed by HPLC and UV-spectroscopy. The results obtained in aqueous solutions showed a dependence of the decomposition as a linear function of the dose. The G of decomposition for a 1x10{sup -5} M solution was 3.3. In the solid state the vitamin was very stable towards the irradiation in the conditions used in this study with a G=2.1x10{sup -3}. A study made with Serratia marcescens as a microbiological contaminant showed that at the sterilization dose there is a destruction of the vitamin in aqueous solution. In the solid state the degree of decomposition was 7%. (author)

  19. Mathematical modeling of water radiolysis in the Syrian MNSR reactor

    International Nuclear Information System (INIS)

    Soukieh, M.

    2009-11-01

    Because it is difficult to measure the concentration of the radiolytic species in reactors under operating conduction, they must be estimated by computer simulation techniques. This study discusses the mathematical modeling of water radiolysis modeling of the MNSR nuclear reactor cooling water. The mathematical model comprising of 13 differential equations describe 55 chemical reactions of radiolytic species e - a q H + , OH - , H, H 2 , OH, HO 2 , O 2 , HO - 2 , O - , O - 2 , O - 3 . The mathematical model have been tested and it shows a good agreement of the computed values in this work with the results cited in references [1,18] in case of only γray irradiation of pure water with dose rate of 1.18x10 19 eV/L s. The neutron fluxes and dose rates at the interface of cladding-water for the different fuel rings in the MNSR core are determined using MCNP-4C code. In addition, the time dependent of the radiolytic specie concentrations were estimated for max. and min. dose rates and at temperature of 20 degree centigrade in the MNSR. The radiolytic specie concentrations reach the steady sate after about 200-400 s. The radiolytic specie concentrations order of H 2 , O 2 , H 2 O 2 were about ppb. Also this study shows the possibility of suppressed the water radiolysis reactions by adding hydrogen to the MNSR reactor cooling water. (author)

  20. Water radiolysis in a crack tip under gamma ray irradiation

    International Nuclear Information System (INIS)

    Satoh, Tomonori; Uchida, Shunsuke; Satoh, Yoshiyuki

    2002-01-01

    Under a non-irradiation condition, oxidant, e.g., O 2 and H 2 O 2 , in a crack tip is supplied from the bulk water. But under irradiation conditions, even if the diffusion of radiolytic species is not sufficient, direct radiolysis in the crack tip causes high concentrations of radiolytic species. As a result of measurements and Monte Carlo calculation of gamma ray energy deposition, it has been confirmed that the energy deposition rate in the gap water is larger than that in the bulk water. The energy absorption rate increases as the gap width decreases and reaches 1.3 times that in the bulk water. In order to evaluate crack propagation rate for irradiation assisted stress corrosion cracking (IASCC) of stainless steel, a water radiolysis model in a crevice is proposed. A larger energy deposition rate in the crevice water produces many more radiolytic species, which causes high oxidant concentrations in spite of enhanced recombination of the species at the crevice inner surface. So, for IASCC evaluation, crevice water chemistry plays an important role to determine the crack propagation rate under irradiation. (authors)