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Sample records for cesium ions

  1. Cesium ion uptake by moss (Hypnum cupressiforme)

    International Nuclear Information System (INIS)

    Lower land mosses uptake water and minerals from the atmosphere. They can collect metals polluting the air and radioactive fallout elements so they can be suitable for monitoring of these substances. Cesium ion uptake by Hypnum cupressiforme is studied by a radioactive tracer, 134Cs. The quantity of cesium ion in different celluar locations and the capacity of ion uptake is determined. The total capacity is found to be several times 10-3 mol g-1 and is therefore of the same order of magnitude as the cation exchange capacity of ion exchangers. The kinetics and reversibility of the process is studied as well. (orig.)

  2. Cesium and strontium ion specific exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Yates, S.

    1996-10-01

    This work is one of two parallel projects that are part of an ESP task to develop high-capacity, selective, solid extractants for cesium, strontium, and technetium from nuclear wastes. In this subtask, Pacific Northwest National Laboratory (PNNL) is collaborating with AlliedSignal, Inc. (Des Plaines, Illinois) to develop inorganic ion exchangers that are selective for strontium and cesium from alkaline high-level waste and groundwater streams.

  3. Composition and process for separating cesium ions from an acidic aqueous solution also containing other ions

    Science.gov (United States)

    Dietz, M.L.; Horwitz, E.P.; Bartsch, R.A.; Barrans, R.E. Jr.; Rausch, D.

    1999-03-30

    A crown ether cesium ion extractant is disclosed as is its synthesis. The crown ether cesium ion extractant is useful for the selective purification of cesium ions from aqueous acidic media, and more particularly useful for the isolation of radioactive cesium-137 from nuclear waste streams. Processes for isolating cesium ions from aqueous acidic media using the crown ether cesium extractant are disclosed as are processes for recycling the crown ether cesium extractant and processes for recovering cesium from a crown ether cesium extractant solution. 4 figs.

  4. Cesium separation Using Electrically Switched Ion Exchange

    International Nuclear Information System (INIS)

    Electrically Switched Ion Exchange (ESIX) is a separation technology being developed at Pacific Northwest National Laboratory as an alternative to conventional ion exchange for removing metal ions from wastewater. In ESIX, which combines ion exchange and electro-chemistry, ion uptake and elution can be controlled directly by modulating the potential of an ion exchange film that has been electrochemically deposited onto an electrode. This paper presents the results of experiments on high surface area electrodes and the development of a flow system for cesium ion separation. Bench-scale flow system studies showed no change in capacity or performance of the ESIX films at a flow rate up to 113 BV/h, the maxi-mum flow rate tested, and breakthrough curves supported once-through waste processing. A comparison of results for a stacked 5-electrode cell versus a single-electrode cell showed enhanced breakthrough performance. In the stacked configuration, break-through began at about 120 BV for a feed containing 0.2 ppm cesium at a flow rate of 13 BV/h. A case study for the KE Basin (a spent nuclear fuel storage basin) on the Hanford Site demonstrated that KE Basin wastewater could be processed continuously with minimal waste generation, reduced disposal costs, and lower capital expenditures

  5. Intense non-relativistic cesium ion beam

    International Nuclear Information System (INIS)

    The Heavy Ion Fusion group at Lawrence Berkeley Laboratory has constructed the One Ampere Cesium Injector as a proof of principle source to supply an induction linac with a high charge density and high brightness ion beam. This is studied here. An electron beam probe was developed as the major diagnostic tool for characterizing ion beam space charge. Electron beam probe data inversion is accomplished with the EBEAM code and a parametrically adjusted model radial charge distribution. The longitudinal charge distribution was not derived, although it is possible to do so. The radial charge distribution that is derived reveals an unexpected halo of trapped electrons surrounding the ion beam. A charge fluid theory of the effect of finite electron temperature on the focusing of neutralized ion beams (Nucl. Fus. 21, 529 (1981)) is applied to the problem of the Cesium beam final focus at the end of the injector. It is shown that the theory's predictions and assumptions are consistent with the experimental data, and that it accounts for the observed ion beam radius of approx. 5 cm, and the electron halo, including the determination of an electron Debye length of approx. 10 cm

  6. Electrically controlled cesium ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Lilga, M. [Pacific Northwest Lab., Richland, WA (United States)

    1996-10-01

    Several sites within the DOE complex (Savannah River, Idaho, Oak Ridge and Hanford) have underground storage tanks containing high-level waste resulting from nuclear engineering activities. To facilitate final disposal of the tank waste, it is advantageous to separate and concentrate the radionuclides for final immobilization in a vitrified glass matrix. This task proposes a new approach for radionuclide separation by combining ion exchange (IX) and electrochemistry to provide a selective and economic separation method.

  7. Ion and electron thermoemission of cesium alumosilicates

    International Nuclear Information System (INIS)

    Relationships between and electron thermoemission of cesium aluminosilicate were studied. Measurements were made at 5.10-8-5.10-9 Tor and temperatures up to 1400 deg C. The effect of additions refractory metals Ti, Mo, Cu and Ir was studied. Ion thermoemission in the pulse regime was also studied. Conclusions are drawn that capacity depends upon additions. The temperature dependence of thermoionic emission current has two maxima and is characterized by instability in time. A conclusion is drawn that aluminosilicate thermionic cathodes can be reckoned as cathodes of a film type

  8. Removal of cesium from wastewater: A cesium-specific ion exchange resin

    International Nuclear Information System (INIS)

    Researchers at the Savannah River Laboratory (SRL) have applied for a patent for an ion exchange resin that will remove cesium from water. Radioactive cesium-137 is a fission product of nuclear reactor operations. Cesium may enter the water of spent fuel holding basins through defects in fuel cladding. Control of cesium in these basins is desirable to keep personnel exposure to a minimum. Cesium is also present in the waste from reprocessing of defense nuclear reactor fuel. Research has been underway at SRL for over a decade to improve management of high-level reprocessing waste. The current technology separates the waste into soluble and insoluble components. Radioactive constituents are removed from the soluble component stream and combined with the insoluble components, which are then converted to a glass for long-term storage. Cesium is the most radioactive constituent of the soluble components stream. The SRL resin is a resorcinol-formaldehyde condensation polymer highly specific for cesium and is about 10 times more effective in removal of cesium than other ion exchange resins evaluated for use in processing defense nuclear waste. Tests have been run at SRL using both simulated and actual waste streams

  9. Evaluation of electrochemical ion exchange for cesium elution

    International Nuclear Information System (INIS)

    Electrochemical elution was investigated as an alternative method to acid elution for the desorption of cesium from loaded ion exchange resins. The approach was found to have several potential advantages over existing technologies, in particular, electrochemical elution eliminates the need for addition of chemicals to elute cesium from the ion exchange resin. Also, since, in the electrochemical elution process the eluting solution is not in direct contact with the ion exchange material, very small volumes of the eluting solution can be used in a complete recycle mode in order to minimize the total volume of the cesium elute. In addition, the cesium is eluted as an alkaline solution that does not require neutralization with caustic to meet the tank farm specifications. Other advantages include easy incorporation of the electrochemical elution process into the present cesium recovery schemes

  10. Cesium ion desorption ionization with Fourier transform mass spectrometry

    International Nuclear Information System (INIS)

    Cesium ions (Cs+) are used for the production of the feed ions necessary to obtain Fourier transform mass spectra (FTMS). The molecule chosen for the initial study of this Cs+ desorption ionization (DI-FTMS) was vitamin B-12 because of its nonvolatile, thermally labile character. 21 references

  11. Electrode activation in cesium-free negative ion sources

    International Nuclear Information System (INIS)

    Features of emission electrode activation leading to enhancement of negative ion emission in cesium-free discharges are discussed. In some ion sources with cesium-free discharges, the emission of negative ions has been increased significantly by emission electrode activation using strong heating of the negative biased electrode by discharge plasma. A simple explanation of this enhancement is that it is due to an accumulation on the emission surface of the plasma electrode of impurities with low ionization potential that decreases in surface work function and increases the secondary emission of negative ions similar to ''Cesiation.'' The negative biasing of emission surface is important for accumulation and trapping the impurities on the emission surface. To effectively control the activation process it is important to directly detect the evolution of the work function and the impurity concentration during electrode activation with enhancement of negative ion emission.

  12. Cesium Ion Exchange Using Tank 241-AN-104 Supernate

    International Nuclear Information System (INIS)

    The River Protection Project is to design and build a high level nuclear waste treatment facility. The waste treatment plant is to process millions of gallons of radioactive waste stored in tanks at the Hanford Site. The high level nuclear waste treatment process includes various unit operations, such as ultrafiltration, precipitation, evaporation, ion exchange, and vitrification. Ion exchange is identified as the optimal treatment method for removal of cesium-137 and Tc-99 from the waste. Extensive ion exchange testing was performed using small-scale columns with actual waste samples. The objectives of this study were to: demonstrate SuperLig 644 ion exchange performance and process steps for the removal of cesium from actual AN-104 tank waste; pretreat actual AN-104 tank waste to reduce the concentration of cesium-137 in the waste below LAW vitrification limit; produce and characterize cesium eluate solutions for use in eluate evaporation tests. The experiments consisted of batch contact and small-scale column tests. The batch contact tests measured sorption partition coefficients Kds. The Kds were used to predict the effective resin capacity. The small-scale column tests, which closely mimic plant conditions, generated loading and elution profile data used to determine whether removal targets and design requirements were met

  13. MODELING RESULTS FROM CESIUM ION EXCHANGE PROCESSING WITH SPHERICAL RESINS

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C.; Hang, T.; Aleman, S.

    2011-01-03

    Ion exchange modeling was conducted at the Savannah River National Laboratory to compare the performance of two organic resins in support of Small Column Ion Exchange (SCIX). In-tank ion exchange (IX) columns are being considered for cesium removal at Hanford and the Savannah River Site (SRS). The spherical forms of resorcinol formaldehyde ion exchange resin (sRF) as well as a hypothetical spherical SuperLig{reg_sign} 644 (SL644) are evaluated for decontamination of dissolved saltcake wastes (supernates). Both SuperLig{reg_sign} and resorcinol formaldehyde resin beds can exhibit hydraulic problems in their granular (nonspherical) forms. SRS waste is generally lower in potassium and organic components than Hanford waste. Using VERSE-LC Version 7.8 along with the cesium Freundlich/Langmuir isotherms to simulate the waste decontamination in ion exchange columns, spherical SL644 was found to reduce column cycling by 50% for high-potassium supernates, but sRF performed equally well for the lowest-potassium feeds. Reduced cycling results in reduction of nitric acid (resin elution) and sodium addition (resin regeneration), therefore, significantly reducing life-cycle operational costs. These findings motivate the development of a spherical form of SL644. This work demonstrates the versatility of the ion exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. The value of a resin with increased selectivity for cesium over potassium can be assessed for further development.

  14. Electrically switched cesium ion exchange. FY 1997 annual report

    International Nuclear Information System (INIS)

    This paper describes the Electrically Switched Ion Exchange (ESIX) separation technology being developed as an alternative to ion exchange for removing radionuclides from high-level waste. Progress in FY 1997 for specific applications of ESIX is also outlined. The ESIX technology, which combines ion exchange and electrochemistry, is geared toward producing electroactive films that are highly selective, regenerable, and long lasting. During the process, ion uptake and elution can be controlled directly by modulating the potential of an ion exchange film that has been electrochemically deposited onto a high surface area electrode. This method adds little sodium to the waste stream and minimizes the secondary wastes associated with traditional ion exchange techniques. Development of the ESIX process is well underway for cesium removal using ferrocyanides as the electroactive films. Films having selectivity for perrhenate (a pertechnetate surrogate) over nitrate also have been deposited and tested. Based on the ferrocyanide film capacity, stability, rate of uptake, and selectivity shown during performance testing, it appears possible to retain a consistent rate of removal and elute cesium into the same elution solution over several load/unload cycles. In batch experiments, metal hexacyanoferrate films showed high selectivities for cesium in concentrated sodium solutions. Cesium uptake was unaffected by Na/Cs molar ratios of up to 2 x 104 , and reached equilibrium within 18 hours. During engineering design tests using 60 pores per inch, high surface area nickel electrodes, nickel ferrocyanide films displayed continued durability. losing less than 20% of their capacity after 1500 load/unload cycles. Bench-scale flow system studies showed no change in capacity or performance of the ESIX films at a flow rate up to 13 BV/h, the maximum flow rate tested, and breakthrough curves further supported once-through waste processing. 9 refs., 24 figs

  15. Uptake of cesium ions by human erythrocytes and perfused rat heart: a cesium-133 NMR study

    Energy Technology Data Exchange (ETDEWEB)

    Davis, D.G.; Murphy, E.; London, R.E.

    1988-05-17

    Cesium-133 NMR studies have been carried out on suspended human erythrocytes and on perfused rat hearts in media containing CsCl. The resulting spectra exhibit two sharp resonances, arising from intra-and extracellular Cs/sup +/, separated in chemical shift by 1.0-1.4 ppm. Thus, intra- and extracellular resonances are easily resolved without the addition of paramagnetic shift reagents required to resolve resonance of the other alkali metal ions. Spin-lattice relaxation times in all cases are monoexponential and significantly shorter (3-4 times) for the intracellular component. When corrections are made for the pulse repetition rate, the total intensity of the intracellular and extracellular Cs/sup +/ resonances in erythrocytes is conserve, implying total observability of the intracellular pool. The uptake of Cs/sup +/ by erythrocytes occurs at approximately one-third the reported rate for K/sup +/ and was reduced by a factor of 2 upon addition of ouabain to the sample. These results indicate that /sup 133/Cs NMR is a promising tool for studying the distribution and transport of cesium ions in biological systems and, in some cases such as uptake by cellular Na,K-ATPase, for analysis of K/sup +/ ion metabolism.

  16. Significant enhancement of negative secondary ion yields by cluster ion bombardment combined with cesium flooding.

    Science.gov (United States)

    Philipp, Patrick; Angerer, Tina B; Sämfors, Sanna; Blenkinsopp, Paul; Fletcher, John S; Wirtz, Tom

    2015-10-01

    In secondary ion mass spectrometry (SIMS), the beneficial effect of cesium implantation or flooding on the enhancement of negative secondary ion yields has been investigated in detail for various semiconductor and metal samples. All results have been obtained for monatomic ion bombardment. Recent progress in SIMS is based to a large extent on the development and use of cluster primary ions. In this work we show that the enhancement of negative secondary ions induced by the combination of ion bombardment with simultaneous cesium flooding is valid not only for monatomic ion bombardment but also for cluster primary ions. Experiments carried out using C60+ and Ar4000+ bombardment on silicon show that yields of negative secondary silicon ions can be optimized in the same way as by Ga+ and Cs+ bombardment. Both for monatomic and cluster ion bombardment, the optimization does not depend on the primary ion species. Hence, it can be assumed that the silicon results are also valid for other cluster primary ions and that results obtained for monatomic ion bombardment on other semiconductor and metal samples are also valid for cluster ion bombardment. In SIMS, cluster primary ions are also largely used for the analysis of organic matter. For polycarbonate, our results show that Ar4000+ bombardment combined with cesium flooding enhances secondary ion signals by a factor of 6. This can be attributed to the removal of charging effects and/or reduced fragmentation, but no major influence on ionization processes can be observed. The use of cesium flooding for the imaging of cells was also investigated and a significant enhancement of secondary ion yields was observed. Hence, cesium flooding has also a vast potential for SIMS analyses with cluster ion bombardment. PMID:26378890

  17. Separation of cesium by ion exchange columns

    International Nuclear Information System (INIS)

    Crystalline silico titanate (CST) has been tested as a selective inorganic ion exchanger to separate Cs 137 from the residual fission product s solution of the Mo 99 plant. The tests are described in detail and show decontamination factors higher than 6000 and a good elution yield

  18. Ion-Induced Nucleation of Cesium Vapor

    Czech Academy of Sciences Publication Activity Database

    Uchtmann, H.; Katz, J. L.; Ždímal, Vladimír

    Vol. 2. Budapest, 2004, S103-S104. [European Aerosol Conference EAC 2004. Budapest (HU), 06.09.2004-10.09.2004] Grant ostatní: NATO(XX) SA979351/6993/FP Institutional research plan: CEZ:AV0Z4072921 Keywords : fundamental aerosol physics * ion-induced nucleation Subject RIV: CF - Physical ; Theoretical Chemistry

  19. Cesium ion exchange using actual waste: Column size considerations

    International Nuclear Information System (INIS)

    It is presently planned to remove cesium from Hanford tank waste supernates and sludge wash solutions using ion exchange. To support the development of a cesium ion exchange process, laboratory experiments produced column breakthrough curves using wastes simulants in 200 mL columns. To verify the validity of the simulant tests, column runs with actual supernatants are being planned. The purpose of these actual waste tests is two-fold. First, the tests will verify that use of the simulant accurately reflects the equilibrium and rate behavior of the resin compared to actual wastes. Batch tests and column tests will be used to compare equilibrium behaviors and rate behaviors, respectively. Second, the tests will assist in clarifying the negative interactions between the actual waste and the ion exchange resin, which cannot be effectively tested with simulant. Such interactions include organic fouling of the resin and salt precipitation in the column. These effects may affect the shape of the column breakthrough curve. The reduction in column size also may change the shape of the curve, making the individual effects even more difficult to sort out. To simplify the evaluation, the changes due to column size must be either understood or eliminated. This report describes the determination of the column size for actual waste testing that best minimizes the effect of scale-down. This evaluation will provide a theoretical basis for the dimensions of the column. Experimental testing is still required before the final decision can be made. This evaluation will be confined to the study of CS-100 and R-F resins with NCAW simulant and to a limited extent DSSF waste simulant. Only the cesium loading phase has been considered

  20. Ion exchange performance of commercial crystalline silicotitanates for cesium removal

    International Nuclear Information System (INIS)

    A new class of inorganic ion exchangers called crystalline silicotitanates (CST), invented by researchers at Sandia National Laboratories and Texas A ampersand M University, has been commercialized in a joint Sandia-UOP effort. The original developmental materials exhibited high selectivity for the ion exchange of cesium, strontium, and several other radionuclides from highly alkaline solutions containing molar concentrations of Na+. The materials also showed excellent chemical and radiation stability. Together, the high selectivity and stability of the CSTs made them excellent candidates for treatment of solutions such as the Hanford tank supernates and other DOE radwastes. Sandia National Laboratories and UOP have teamed under a Cooperative Research and Development Agreement (CRADA) to develop CSTs in the powdered form and in an engineered form suitable for column ion exchange use. A continuous-flow, column ion exchange process is expected to be used to remove Cs and other radionuclides from the Hanford supernatant. The powder material invented by the Sandia and Texas A ampersand M team consists of submicron-size particles. It is not designed for column ion exchange but may be used in other applications

  1. Ion exchange performance of commercial crystalline silicotitanates for cesium removal

    Energy Technology Data Exchange (ETDEWEB)

    Braun, R.; Dangieri, T.J.; Fennelly, D.J. [and others

    1996-03-01

    A new class of inorganic ion exchangers called crystalline silicotitanates (CST), invented by researchers at Sandia National Laboratories and Texas A&M University, has been commercialized in a joint Sandia-UOP effort. The original developmental materials exhibited high selectivity for the ion exchange of cesium, strontium, and several other radionuclides from highly alkaline solutions containing molar concentrations of Na{sup +}. The materials also showed excellent chemical and radiation stability. Together, the high selectivity and stability of the CSTs made them excellent candidates for treatment of solutions such as the Hanford tank supernates and other DOE radwastes. Sandia National Laboratories and UOP have teamed under a Cooperative Research and Development Agreement (CRADA) to develop CSTs in the powdered form and in an engineered form suitable for column ion exchange use. A continuous-flow, column ion exchange process is expected to be used to remove Cs and other radionuclides from the Hanford supernatant. The powder material invented by the Sandia and Texas A&M team consists of submicron-size particles. It is not designed for column ion exchange but may be used in other applications.

  2. Vitrification of cesium-contaminated organic ion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Sargent, T.N. Jr. [Clemson Univ., SC (United States)

    1994-08-01

    Vitrification has been declared by the Environmental Protection Agency (USEPA) as the Best Demonstrated Available Technology (BDAT) for the permanent disposal of high-level radioactive waste. Savannah River Site currently uses a sodium tetraphenylborate (NaTPB) precipitation process to remove Cs-137 from a wastewater solution created from the processing of nuclear fuel. This process has several disadvantages such as the formation of a benzene waste stream. It has been proposed to replace the precipitation process with an ion exchange process using a new resorcinol-formaldehyde resin developed by Savannah River Technical Center (SRTC). Preliminary tests, however, showed that problems such as crust formation and a reduced final glass wasteform exist when the resin is placed in the melter environment. The newly developed stirred melter could be capable of overcoming these problems. This research explored the operational feasibility of using the stirred tank melter to vitrify an organic ion exchange resin. Preliminary tests included crucible studies to determine the reducing potential of the resin and the extent of oxygen consuming reactions and oxygen transfer tests to approximate the extent of oxygen transfer into the molten glass using an impeller and a combination of the impeller and an external oxygen transfer system. These preliminary studies were used as a basis for the final test which was using the stirred tank melter to vitrify nonradioactive cesium loaded organic ion exchange resin. Results from this test included a cesium mass balance, a characterization of the semi-volatile organic compounds present in the off gas as products of incomplete combustion (PIC), a qualitative analysis of other volatile metals, and observations relating to the effect the resin had on the final redox state of the glass.

  3. Vitrification of cesium-contaminated organic ion exchange resin

    International Nuclear Information System (INIS)

    Vitrification has been declared by the Environmental Protection Agency (USEPA) as the Best Demonstrated Available Technology (BDAT) for the permanent disposal of high-level radioactive waste. Savannah River Site currently uses a sodium tetraphenylborate (NaTPB) precipitation process to remove Cs-137 from a wastewater solution created from the processing of nuclear fuel. This process has several disadvantages such as the formation of a benzene waste stream. It has been proposed to replace the precipitation process with an ion exchange process using a new resorcinol-formaldehyde resin developed by Savannah River Technical Center (SRTC). Preliminary tests, however, showed that problems such as crust formation and a reduced final glass wasteform exist when the resin is placed in the melter environment. The newly developed stirred melter could be capable of overcoming these problems. This research explored the operational feasibility of using the stirred tank melter to vitrify an organic ion exchange resin. Preliminary tests included crucible studies to determine the reducing potential of the resin and the extent of oxygen consuming reactions and oxygen transfer tests to approximate the extent of oxygen transfer into the molten glass using an impeller and a combination of the impeller and an external oxygen transfer system. These preliminary studies were used as a basis for the final test which was using the stirred tank melter to vitrify nonradioactive cesium loaded organic ion exchange resin. Results from this test included a cesium mass balance, a characterization of the semi-volatile organic compounds present in the off gas as products of incomplete combustion (PIC), a qualitative analysis of other volatile metals, and observations relating to the effect the resin had on the final redox state of the glass

  4. Cesium ion exchange kinetics with PAN-KCoFC composite ion exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jei Kwong; Han, Yoon Ju; Lee, Eil Hee; Jung, Chong Hun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Lee, Byung Chul [Hannam University, Taejon (Korea, Republic of)

    2004-07-01

    PAN based inorganic-organic composite ion exchanger beads are recently reviewed as promising one for removal of radionuclides due to their characterizing advantages, no dissolution in liquid solution and no pressure drop problem in column operation, over the existing inorganic ion exchangers such as zeolites. Also since the PAN acts as an inert binder all radionuclides are bound to inorganic materials. Therefore no radionuclides release occurs even when they are decomposed underground. In this study, ion exchange kinetics for cesium ion was performed using a PAN-KCoFC composite ion exchanger in a batch reactor together with column system.

  5. Cesium ion exchange kinetics with PAN-KCoFC composite ion exchanger

    International Nuclear Information System (INIS)

    PAN based inorganic-organic composite ion exchanger beads are recently reviewed as promising one for removal of radionuclides due to their characterizing advantages, no dissolution in liquid solution and no pressure drop problem in column operation, over the existing inorganic ion exchangers such as zeolites. Also since the PAN acts as an inert binder all radionuclides are bound to inorganic materials. Therefore no radionuclides release occurs even when they are decomposed underground. In this study, ion exchange kinetics for cesium ion was performed using a PAN-KCoFC composite ion exchanger in a batch reactor together with column system

  6. High voltage holding in the negative ion sources with cesium deposition

    Energy Technology Data Exchange (ETDEWEB)

    Belchenko, Yu.; Abdrashitov, G.; Ivanov, A.; Sanin, A.; Sotnikov, O., E-mail: O.Z.Sotnikov@inp.nsk.su [Budker Institute of Nuclear Physics, Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2016-02-15

    High voltage holding of the large surface-plasma negative ion source with cesium deposition was studied. It was found that heating of ion-optical system electrodes to temperature >100 °C facilitates the source conditioning by high voltage pulses in vacuum and by beam shots. The procedure of electrode conditioning and the data on high-voltage holding in the negative ion source with small cesium seed are described. The mechanism of high voltage holding improvement by depletion of cesium coverage is discussed.

  7. Increasing the Space Charge Limit and Other Effects of Cesium Seeding in Hydrogen Negative Ion Sources

    International Nuclear Information System (INIS)

    The role of cesium seeding in increasing the negative ion current in volume sources is described. By a reduction in the local plasma potential the current of extracted electrons is vastly reduced. As a result, cesium increases the fraction of the transverse space charge limit available to the ions by as much as a factor of three. In addition, cesium can increase the total space charge limit by injection of Cs+ into the presheath-a newly recognized phenomenon consistent with experimental measurements and determined from application of a Double-Vlasov model for negative ion extraction

  8. A new ion exchanger for the removal of cesium from aqueous solutions

    International Nuclear Information System (INIS)

    A new exchange potassium copper nickel hexacyanoferrates(II) was prepared. It was characterized by chemical composition and surface area measurements. The removal of cesium from aqueous solution by ion exchange was studied as function of shaking time. pH and concentration of acids, salts and cesium. The data indicates high value of distribution coefficient over a wide range of pH, nitric and hydrochloric acids concentration and in the presence of higher concentration of Na and K ions. A potassium copper nickel hexacyanoferrate(II) column was also tested for elution of cesium using 8 M ammonium nitrate solution. (author)

  9. Pillared montmorillonites: Cesium-selective ion-exchange materials

    Energy Technology Data Exchange (ETDEWEB)

    Sylvester, P.; Clearfield, A.; Diaz, R.J. [Texas A and M Univ., College Station, TX (United States). Dept. of Chemistry

    1999-09-01

    A zirconia-pillared and an alumina-pillared montmorillonite clay were found to exhibit high K{sub d}S for trace levels of cesium (2.5 ppb) in the presence of high concentrations of Ca{sup 2+}, Mg{sup 2+}, and Na{sup +} ions with distribution coefficients (K{sub d}S) for {sup 137}Cs exceeding 1 {times} 10{sup 5} mL/g over a wide range of competing ion concentrations. An excess of K{sup +} ions, however, caused a dramatic reduction in the Cs K{sub d}S for both of the materials. These results were in contrast to the parent montmorillonite which exhibited far lower K{sub d}S for {sup 137}Cs, particularly in the presence of high concentrations of Mg{sup 2+} and Ca{sup 2+}. Batch tests in simulated groundwaters showed that both pillared clays efficiently removed {sup 137}Cs from solution, with the best K{sub d}S being approximately 8.5 {times} 10{sup 5} mL/g in a potassium-free groundwater. The materials performed less well in a groundwater with a high potassium concentration, but still gave K{sub d}S similar to commercially available zeolites. The rate of {sup 137}Cs uptake was found to be rapid with both the alumina- and zirconia-pillared clays extracting >90% of the {sup 137}Cs from a 0.1 M NaNO{sub 3} solution within 5 minutes.

  10. Development of electrochemical ion exchange electrodes for the treatment of wastes containing chromium or cesium ions

    International Nuclear Information System (INIS)

    Nowadays, environmental preservation using technologies that do not attack it, generating non-toxic residues and reduced volumes, has been discussed. Hazardous effluents, containing metals, as chromium, have been poured in the soils and rivers, degrading the water. Not different are the problems originated from some nuclear activities that generate wastes, as in chemical research laboratories. Although those wastes are not poured in the environment, sometimes they are inadequately stored, what can cause serious accidents. With the purpose of solving this problem, there are some techniques to waste treatment, between them there is the electrochemical ion exchange (EIX). EIX is an advanced process that has advantages over traditional ion exchange and the fact of using the electron as the only reagent, reduces the volume of the solution to be treated. This technique consists of development of an electrode, where an ion exchanger is physically incorporated in an electrode structure with a binder. In this study, cationic resin Amberlite CG-50 and zirconium phosphate have been chosen for the separation of chromium and cesium from waste, respectively. They were chosen because they present high chemical stability in oxidizing media and at ionizing radiation. The quantity of charcoal, graphite and binder used in formulation of electrode have been studied either. Before choosing the best electrode, it was verified sorption percentage of 99,3% for chromium and 99,8% for cesium. The greater advantage of this process is the total elution of chromium as much as cesium, without reagents addition, being possible to reuse the electrode without losing its capacity. Beside on the results, a continuous process for the wastes containing Cr and Cs, using a flux electrolytic cell (CELFLUX) of high retention capacity, was presented. The high efficiency of this cell for both retention and elution, leading to an important reduction of waste volume, and, every more, making possible the

  11. Equilibrium data for cesium ion exchange of Hanford CC and NCAW tank waste

    International Nuclear Information System (INIS)

    Hanford alkaline waste storage-tank contents will be processed to remove the soluble salts. A major fraction of these solutions will require cesium recovery to produce a low-level waste (LLW). The technology for decontamination of high-level alkaline waste and sludge wash waters is being developed. At the request of Westinghouse Hanford Company (WHC), the Pacific Northwest Laboratory (PNL) has studied several ion exchange materials for the recovery of cesium from Hanford waste tanks. The WHC program was divided into tow main tasks, (1) to obtain equilibrium data for cesium ion exchange, and (2) to evaluate ion exchange column performance. The subject of this letter report is the measurement of batch distribution coefficients for several ion exchange media for a range of operating conditions for two types of waste; complexant concentrate (CC) and neutralized current acid waste (NCAW)

  12. Synthesis of novel calixcrown derivatives with selective complexation towards cesium ions

    Institute of Scientific and Technical Information of China (English)

    Lu Zhang; Juan Du; Li Hua Yuan; Dong Zhang; Gui Ping Dan; Yuan You Yang; Wen Feng

    2011-01-01

    A series of novel calix [4]arenecrown-6 derivatives with an alkenyl loop of various sizes 5-8 were synthesized via intramolecular ring closing olefin metathesis and characterized by 1H NMR, 13C NMR and ESI-HRMS. Their complexation property towards cesium ion was studied by 'H NMR technique. Two-phase extraction of alkali metal ions using UV-vis spectroscopy revealed remarkably different extractabilities. These results indicate that the complexation capacities towards cesium ions can be tuned and controlled through cooperative regulation of the strain of the loop and conformational change of calixcrown skelton.

  13. Vitrification of spent organic ion exchange resins- 137Cesium volatility during oxidation

    International Nuclear Information System (INIS)

    Organic ion exchange (IX) resins are used to purify coolant water in nuclear power plants. The spent IX resins contain 137Cesium as major long-lived radioisotope. Their vitrification requires complete combustion of organic matter. 137Cesium volatility during their oxidation is most important factor for selection of oxidation procedure. Based on TGA studies, copper and vanadate catalysts were selected respectively for cationic and anionic IX resins to oxidise them at 500-700 degC. Experiments were conducted with 137Cesium and catalyst loaded cationic and anionic resins. About 56 to 60% 137Cesium was released from cationic resins in 3 hours. 137Cesium release from cationic resins could be brought down to 19 to 22% by addition of glass formers. The 137Cesium releases from anionic resins were nearly same for 2 hours heating. In absence of glass formers, the catalyst on anionic resins formed molten mass, which was difficult to remove. Experiment with one litre of 137Cesiuin loaded mixed cationic and anionic resins released 16.8% 137Cesium to off gases and formed a slag having specific gravity of 1.73 due to difficulty in oxidising last traces of carbon. The volume reduction factor achieved was 18.2 as against 68 expected for complete oxidation of IX resins. The higher volume reduction factor can be achieved by using improved oxidation procedure in scaling up studies. (author)

  14. Modeling Ion-Exchange Processing With Spherical Resins For Cesium Removal

    Energy Technology Data Exchange (ETDEWEB)

    Hang, T.; Nash, C. A.; Aleman, S. E.

    2012-09-19

    The spherical Resorcinol-Formaldehyde and hypothetical spherical SuperLig(r) 644 ion-exchange resins are evaluated for cesium removal from radioactive waste solutions. Modeling results show that spherical SuperLig(r) 644 reduces column cycling by 50% for high-potassium solutions. Spherical Resorcinol Formaldehyde performs equally well for the lowest-potassium wastes. Less cycling reduces nitric acid usage during resin elution and sodium addition during resin regeneration, therefore, significantly decreasing life-cycle operational costs. A model assessment of the mechanism behind ''cesium bleed'' is also conducted. When a resin bed is eluted, a relatively small amount of cesium remains within resin particles. Cesium can bleed into otherwise decontaminated product in the next loading cycle. The bleed mechanism is shown to be fully isotherm-controlled vs. mass transfer controlled. Knowledge of residual post-elution cesium level and resin isotherm can be utilized to predict rate of cesium bleed in a mostly non-loaded column. Overall, this work demonstrates the versatility of the ion-exchange modeling to study the effects of resin characteristics on processing cycles, rates, and cold chemical consumption. This evaluation justifies further development of a spherical form of the SL644 resin.

  15. Preparation, structure and application of a new ecomaterials cesium ion-sieve

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new ecomaterials cesium ion-sieve (Cs-IS), which has high selectivity to cesium and excellent acid resistance, is prepared with zirconyl molybdopyrophosphate as its matrix by specific chemical sieve-making means. Cs-IS has large exchange capacity ( 1.83mmol@g-1) and high distribution coefficient (4.09 x 104 mL@ L-1) in the medium of 3 mol@ L- 1 HNO3. In the static exchange with strongly acidic high-level radioactive liquid waste (HLLW) (3 mol@ L-1 HNO3), Cs-IS exhibits high exchange rate for cesium (above 96.53 % ) and large separation factor (greater than 958.41). These indicate the possible use of Cs-IS in cesium-137 selective removal and recovery from highly saline acidic HLLW system.

  16. Effect of electrolytes concentration on recovery of cesium from AMP-PAN by Electrodialysis-Ion Exchange (EDIX)

    International Nuclear Information System (INIS)

    Cesium from the simulated acidic waste solution was separated using Ammonium Molybdophosphate (AMP) - Polyacrylonitrile (PAN) ion exchange resin in column operations. Electrodialysis - Ion exchange (EDIX) has been tried for the recovery of cesium from the AMP-PAN which was saturated with cesium. The electrodialysis setup consists of three compartments; cesium loaded AMP-PAN is placed in the middle compartment and is separated from the anode and cathode compartments by cation exchange membranes. Ammonium sulphate was used as anolyte and HNO3 as catholyte. 0.1N HNO3 was circulated in the middle compartment containing AMP-PAN to keep the resin in acidic form. On application of potential, the ammonium ions from the anode compartment migrate towards cathode through the middle compartment where they exchange with cesium ions on the resin and the exchanged cesium ions migrate towards cathode to get concentrated. Some part of cesium is recovered in the middle compartment due to convection. Cesium recovery from the AMP-PAN in the electrodialysis setup was studied at different anolyte and catholyte concentrations. All the experiments were carried out at constant current density of 40 mA/cm2 for 15h. It was found that more than 50% of cesium recovery was observed for all the experiments studied and recovery percentage increased with increasing the anolyte concentration. It was observed that the electrolytes concentration affects the voltage drop across the cell

  17. Laboratory evaluation of an ion exchange process for removing cesium from Purex acid waste solutions

    International Nuclear Information System (INIS)

    A laboratory investigation was made of an ion exchange process for removing radioactive cesium from acidic Purex waste. Twenty-seven laboratory ion exchanger runs are reported. Parameters investigated include comparison of Zeolon-900, AW-500 and Duolite ARC-359 ion exchangers, pH of feed solutions, composition of sodium scrub solutions, composition of eluting solutions and overflow versus downflow elution. The cause and rate of zeolite degradation was investigated

  18. Assessment of commercially available ion exchange materials for cesium removal from highly alkaline wastes

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, K.P.; Kim, A.Y.; Kurath, D.E.

    1996-04-01

    Approximately 61 million gallons of nuclear waste generated in plutonium production, radionuclide removal campaigns, and research and development activities is stored on the Department of Energy`s Hanford Site, near Richland, Washington. Although the pretreatment process and disposal requirements are still being defined, most pretreatment scenarios include removal of cesium from the aqueous streams. In many cases, after cesium is removed, the dissolved salt cakes and supernates can be disposed of as LLW. Ion exchange has been a leading candidate for this separation. Ion exchange systems have the advantage of simplicity of equipment and operation and provide many theoretical stages in a small space. The organic ion exchange material Duolite{trademark} CS-100 has been selected as the baseline exchanger for conceptual design of the Initial Pretreatment Module (IPM). Use of CS-100 was chosen because it is considered a conservative, technologically feasible approach. During FY 96, final resin down-selection will occur for IPM Title 1 design. Alternate ion exchange materials for cesium exchange will be considered at that time. The purpose of this report is to conduct a search for commercially available ion exchange materials which could potentially replace CS-100. This report will provide where possible a comparison of these resin in their ability to remove low concentrations of cesium from highly alkaline solutions. Materials which show promise can be studied further, while less encouraging resins can be eliminated from consideration.

  19. Assessment of commercially available ion exchange materials for cesium removal from highly alkaline wastes

    International Nuclear Information System (INIS)

    Approximately 61 million gallons of nuclear waste generated in plutonium production, radionuclide removal campaigns, and research and development activities is stored on the Department of Energy's Hanford Site, near Richland, Washington. Although the pretreatment process and disposal requirements are still being defined, most pretreatment scenarios include removal of cesium from the aqueous streams. In many cases, after cesium is removed, the dissolved salt cakes and supernates can be disposed of as LLW. Ion exchange has been a leading candidate for this separation. Ion exchange systems have the advantage of simplicity of equipment and operation and provide many theoretical stages in a small space. The organic ion exchange material Duolite trademark CS-100 has been selected as the baseline exchanger for conceptual design of the Initial Pretreatment Module (IPM). Use of CS-100 was chosen because it is considered a conservative, technologically feasible approach. During FY 96, final resin down-selection will occur for IPM Title 1 design. Alternate ion exchange materials for cesium exchange will be considered at that time. The purpose of this report is to conduct a search for commercially available ion exchange materials which could potentially replace CS-100. This report will provide where possible a comparison of these resin in their ability to remove low concentrations of cesium from highly alkaline solutions. Materials which show promise can be studied further, while less encouraging resins can be eliminated from consideration

  20. Separation of low concentration of cesium ion from wastewater by electrochemically switched ion exchange method: Experimental adsorption kinetics analysis

    International Nuclear Information System (INIS)

    Highlights: ► A continuous cesium separation and regeneration process based on ESIX could be achieved by a diaphragm-isolated reactor. ► The adsorption/desorption rate of Cs+ could be increased by applied potential. ► H3O+ played a dual role of electrolyte and competitor. ► A pseudo-first-order kinetics model could be used to describe the adsorption rate of cesium in the ESIX process. ► The ESIX of cesium consisted of ESIX step and ion diffusion step. - Abstract: A series of experiments were performed to evaluate the continuous separation of cesium based on an electrochemically switched ion exchange (ESIX) process using a diaphragm-isolated reactor with two identical nickel hexacyanoferrate/porous three-dimensional carbon felt (NiHCF/PTCF) electrodes as working electrodes. The effects of applied potential, initial concentrations and pH values of the simulation solutions on the adsorption of cesium ion were investigated. The adsorption rate of cesium ion in the ESIX process was fitted by a pseudo-first-order reaction model. The experiments revealed that the introduction of applied potential on the electrodes greatly enhanced the adsorption/desorption rate of Cs+ and increased the separation efficiency. H3O+ was found to play a dual role of electrolyte and competitor, and the adsorption rate constant showed a curve diversification with an increase in pH value. Also, it was found that the electrochemically switched adsorption process of Cs+ by NiHCF/PTCF electrodes proceeded in two main steps, i.e., an ESIX step with a fast adsorption rate and an ion diffusion step with a slow diffusion rate. Meanwhile, the NiHCF/PTCF film electrode showed adsorption selectivity for Cs+ in preference to Na+.

  1. Enhanced capacity and stability for the separation of cesium in electrically switched ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Tawfic, A.F.; Dickson, S.E.; Kim, Y. [McMaster University, Hamilton, ON (Canada); Mekky, W. [AMEC NSS, Power and Process America, Toronto (Canada)

    2015-03-15

    Electrically switched ion exchange (ESIX) can be used to separate ionic contaminants from industrial wastewater, including that generated by the nuclear industry. The ESIX method involves sequential application of reduction and oxidation potentials to an ion exchange film to induce the respective loading and unloading of cesium. This technology is superior to conventional methods (e.g electrodialysis reversal or reverse osmosis) as it requires very little energy for ionic separation. In previous studies, ESIX films have demonstrated relatively low ion exchange capacities and limited film stabilities over repeated potential applications. In this study, the methodology for the deposition of electro-active films (nickel hexacyanoferrate) on nickel electrodes was modified to improve the ion exchange capacity for cesium removal using ESIX. Cyclic voltammetry was used to investigate the ion exchange capacity and stability. Scanning electron microscopy (SEM) was used to characterize the modified film surfaces. Additionally, the films were examined for the separation of cesium ions. This modified film preparation technique enhanced the ion exchange capacity and improves the film stability compared to previous methods for the deposition of ESIX films. (authors)

  2. Sugar-metal ion interactions: The coordination behavior of cesium ion with lactose, D-arabinose and L-arabinose

    Science.gov (United States)

    Jiang, Ye; Xue, Junhui; Wen, Xiaodong; Zhai, Yanjun; Yang, Limin; Xu, Yizhuang; Zhao, Guozhong; Kou, Kuan; Liu, Kexin; Chen, Jia'er; Wu, Jinguang

    2016-04-01

    The novel cesium chloride-lactose complex (CsCl·C12H22O10 (Cs-Lac), cesium chloride-D-arabinose and L-arabinose complexes (CsCl·C5H10O5, Cs-D-Ara and Cs-L-Ara) have been synthesized and characterized using X-ray diffraction, FTIR, FIR, THz and Raman spectroscopies. Cs+ is 9-coordinated to two chloride ions and seven hydroxyl groups from five lactose molecules in Cs-Lac. In the structures of CsCl-D-arabinose and CsCl-L-arabinose complexes, two kinds of Cs+ ions coexist in the structures. Cs1 is 10-coordinated with two chloride ions and eight hydroxyl groups from five arabinose molecule; Cs2 is 9-coordinated to three chloride ions and six hydroxyl groups from five arabinose molecules. Two coordination modes of arabinose coexist in the structures. α-D-arabinopyranose and α-L-arabinopyranose appear in the structures of Cs-D-Ara and Cs-L-Ara complexes. FTIR and Raman results indicate variations of hydrogen bonds and the conformation of the ligands after complexation. FIR and THz spectra also confirm the formation of Cs-complexes. Crystal structure, FTIR, FIR, THz and Raman spectra provide detailed information on the structure and coordination of hydroxyl groups to metal ions in the cesium chloride-lactose, cesium chloride-D- and L-arabinose complexes.

  3. Comparison of organic and inorganic ion exchange materials for removal of cesium and strontium from tank waste

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-10-01

    This work is part of an ESP task to develop high-capacity, selective, solid extractants for cesium, strontium, and technetium from nuclear wastes. Pacific Northwest National Laboratory (PNNL) staff are investigating novel ion exchangers for use in nuclear waste remediation (groundwater, high-level waste (HLW), and low-level waste (LLW)). Waste components targeted for remediation include cesium, strontium, and technetium.

  4. Small-Column Cesium Ion Exchange Elution Testing of Spherical Resorcinol-Formaldehyde

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Garrett N.; Russell, Renee L.; Peterson, Reid A.

    2011-10-21

    This report summarizes the work performed to evaluate multiple, cesium loading, and elution cycles for small columns containing SRF resin using a simple, high-level waste (HLW) simulant. Cesium ion exchange loading and elution curves were generated for a nominal 5 M Na, 2.4E-05 M Cs, 0.115 M Al loading solution traced with 134Cs followed by elution with variable HNO3 (0.02, 0.07, 0.15, 0.23, and 0.28 M) containing variable CsNO3 (5.0E-09, 5.0E-08, and 5.0E-07 M) and traced with 137Cs. The ion exchange system consisted of a pump, tubing, process solutions, and a single, small ({approx}15.7 mL) bed of SRF resin with a water-jacketed column for temperature-control. The columns were loaded with approximately 250 bed volumes (BVs) of feed solution at 45 C and at 1.5 to 12 BV per hour (0.15 to 1.2 cm/min). The columns were then eluted with 29+ BVs of HNO3 processed at 25 C and at 1.4 BV/h. The two independent tracers allowed analysis of the on-column cesium interaction between the loading and elution solutions. The objective of these tests was to improve the correlation between the spent resin cesium content and cesium leached out of the resin in subsequent loading cycles (cesium leakage) to help establish acid strength and purity requirements.

  5. Small-Scale Ion Exchange Removal of Cesium and Technetium from Hanford Tank 241-AN-103

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, N.M.

    2000-07-27

    The pretreatment process for BNFL, Inc.'s Hanford River Protection Project is to provide decontaminated low activity waste and concentrated eluate streams for vitrification into low activity and high level waste glass, respectively. The pretreatment includes sludge washing, filtration, precipitation, and ion exchange processes to remove entrained solids, cesium, transuranics, technetium, and strontium. The ion exchange removal of cesium (Cs) and technetium (Tc) ions is accomplished by using SuperLig 644, and 639 resins from IBC Advanced Technologies, American Fork, Utah. The resins were shown to selectively remove cesium and technetium (as pertechnetate), from alkaline salt solutions. The efficiency of ion exchange column loading and elution is a complex function involving feed compositions, equilibrium and kinetic behavior of ion exchange resins, diffusion, and the ionic strength and pH of the aqueous solution. A previous experimental program completed at the Savannah River Technology Center demonstrated the conceptualized flow sheet parameters with a similar Hanford tank sample (241-AW-101). Those experiments included determination of Cs and Tc batch distribution coefficients by SuperLig 644 and 639 resins and demonstration of small-scale column breakthrough and elution. The experimental findings were used in support of preliminary design bases and pretreatment flow sheet development by BNFL, Inc.

  6. Experiments and simulations for the dynamics of cesium in negative hydrogen ion sources for ITER N-NBI

    International Nuclear Information System (INIS)

    The injection of fast neutral particles (NBI) into a fusion plasma is an important method for plasma heating and current drive. A source for negative deuterium ions delivering an 1 MeV beam that is accelerated to a specific energy and neutralized by a gas target is required for the ITER-NBI. Cesium seeding is required to extract high negative ion current densities from these sources. The optimization of the cesium homogeneity and control are major objectives to achieve the source requirements imposed by ITER. Within the scope of this thesis, the Monte Carlo based numerical transport simulation CsFlow3D was developed, which is the first computer model that is capable of simulating the flux and the accumulation of cesium on the surfaces of negative-ion sources. Basic studies that support the code development were performed at a dedicated experiment at the University of Augsburg. Input parameters of the ad- and desorption of cesium at ion source relevant conditions were taken from systematic measurements with a quartz micro balance, while the injection rate of the cesium oven at the ion source was determined by surface ionization detection. This experimental setup was used for further investigations of the work function of cesium-coated samples during plasma exposure. (orig.)

  7. Experiments and simulations for the dynamics of cesium in negative hydrogen ion sources for ITER N-NBI

    Energy Technology Data Exchange (ETDEWEB)

    Gutser, Raphael

    2010-07-21

    The injection of fast neutral particles (NBI) into a fusion plasma is an important method for plasma heating and current drive. A source for negative deuterium ions delivering an 1 MeV beam that is accelerated to a specific energy and neutralized by a gas target is required for the ITER-NBI. Cesium seeding is required to extract high negative ion current densities from these sources. The optimization of the cesium homogeneity and control are major objectives to achieve the source requirements imposed by ITER. Within the scope of this thesis, the Monte Carlo based numerical transport simulation CsFlow3D was developed, which is the first computer model that is capable of simulating the flux and the accumulation of cesium on the surfaces of negative-ion sources. Basic studies that support the code development were performed at a dedicated experiment at the University of Augsburg. Input parameters of the ad- and desorption of cesium at ion source relevant conditions were taken from systematic measurements with a quartz micro balance, while the injection rate of the cesium oven at the ion source was determined by surface ionization detection. This experimental setup was used for further investigations of the work function of cesium-coated samples during plasma exposure. (orig.)

  8. Some probe experiments on a high energy cesium ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Hubach, R. A.; Peppin, G. B.

    1963-03-31

    A probe has been developed which is, in effect, a directional Langmuir probe. The directional quality is necessary for use in a beam of high energy ions to eliminate the effects of the streaming ions on the probe operation. This probe has been utilized to measure the back-streaming (albedo) electron component to verify the bottle model of space-charge neutralization. It has also been possible to infer the density of slow ions in the beam created by gas ionization and to infer a value of the cross section for such gas ionization which .agrees with the anticipated value. (auth)

  9. Flame photometric determination of cesium ion after its preconcentration with nanoparticles imprinted with the cesium-dibenzo-24-crown-8 complex

    International Nuclear Information System (INIS)

    We report on the synthesis of cesium ion-imprinted polymer nanoparticles that were prepared by a precipitation polymerization strategy using dibenzo-24-crown-8 ether as a selective crown ether, methacrylic acid as the functional monomer, ethyleneglycol dimethacrylate as the crosslinker, and AIBN as the radical initiator. The prepared sorbents have a diameter of 50-90 nm and display highly selective binding capability for Cs(I) ion, with rapid adsorption and desorption. The maximum adsorption capacity is 50 mg g-1, and the preconcentration factor is around 100 at pH 9.0. Cesium ion was then determined by flame photometry with a detection limit (3σ) of 0.7 ng mL-1 and with a standard deviation of 0.9 %. (author)

  10. Estimation of cesium ion exchange distribution coefficients for concentrated electrolytic solutions when using crystalline silicotitanates

    International Nuclear Information System (INIS)

    Polzer et al.'s method combined with Bromley's method for estimating activity coefficients and a Langmuir isotherm for cesium in a simple simulated waste solution containing 5.1 M NaNO3 and 0.6 M NaOH was used to estimate distribution coefficients for cesium in a complex simulated waste solution characteristic of the radioactive tank wastes at Hanford and other US Department of energy sites. The ion exchange material was a hydrous sodium crystalline silicotitanate, labeled TAM-5, which is being developed by Texas A and M University, Sandia National Laboratories, and UOP Associates. Cesium distribution coefficients collected by Bray et al. on a NCAW simulated waste solution were predicted with deviations of less than 25% for solutions containing 1 M, 3 M, and 5 M Na+ and Na:Cs ratios of 103--108. The deviations were less than 5% for the solutions with 1 M Na+. Cesium distribution coefficients were also predicted and compared with values measured by Egan et al. for TAM-5 and for a storage tank supernate and a newly generated waste solution. Excellent results were obtained for the newly generated waste simulated solution, which did not contain potassium or rubidium.The predictions for the other simulated waste solution were significantly greater than the measured values, because of the presence of large concentrations of potassium or rubidium. The effect of competitive ion exchange between Cs, Rb, and K was not included in the theory. However, the effect of competitive ion exchange between Cs, Rb, and K was not included in the theory. However, the effect of competitive exchange of Cs, Rb, and K appears to be greater for the Oak Ridge simulated waste solution than for the NCAW waste

  11. Process for separating cesium ions from aqueous solutions

    International Nuclear Information System (INIS)

    A precipitation agent is added to the aqueous solution and the resulting precipitate containing Cs+ ions is separated from the solution. By this process, caesium is to be separated selectively compared with other alkaline metal ions with great efficiency from aqueous solutions, particularly aqueous MAW (medium activity waste). This is achieved by using a sodium tetraphenyl borate attracting electrons to the phenyl rings and having substitutes. (orig./PW)

  12. Production of negative D- ions by double charge exchange using cesium

    International Nuclear Information System (INIS)

    The first experimental results on the source of D- negative ions developed at SIG confirm a certain number of essential points: (1) the use of a positive ion source obtained by a resonance electronic cyclotron permits the production of D+ ion beams with a very small gas output, therefore it has a very good gas efficiency; (2) the supersonic cesium target obtained after the release of a high temperature cesium vapor functions perfectly with the desired characteristics; (3) the conversion efficiency measured in D- ions is close to those which were deduced from experimental cross sections; and (4) the mean density of D- ion currents is on the order of 10 mA/cm2 at 1 keV. They could be 15 at 25 mA/cm2 at 300 eV. This presupposes that we modify the extraction optic for the D+ ions to extract 60 at 70 mA/cm2 of D+ at 300 eV with a maximum electric field of 30 DV/cm and a greater perveance of the optic

  13. Highly Selective Removal of Cesium and Strontium Utilizing a New Class of Inorganic Ion Specific Media

    International Nuclear Information System (INIS)

    Radionuclides such as Cesium-137 and Strontium-90 are key drivers of liquid waste classification at light water reactors and within the DOE tank farm complexes. The treatment, storage, and disposal of these wastes represents a major cost for nuclear power plant operators, and comprises one of the most challenging technology-driven projects for the DOE Environmental Management (EM) program. Selective removal of specified isotopes through ion exchange is a common and proven treatment method for liquid waste, yet various aspects of existing technologies leave room for improvement with respect to both cost and effectiveness. We demonstrate a novel class of inorganic ion-exchangers for the selective removal of cesium and strontium, the first of a growing family of patent-pending, potentially elutable, and paramagnetic ion-exchange materials. These highly selective inorganic ion-exchangers display strong chemical, thermal and radiation stability, and can be readily synthesized from low-cost materials, making them a promising alternative to organic ion-exchange resins and crystalline silico-titanate (CST). The introduction of this new family of highly specific ion-exchange agents has potential to both reduce the cost of waste processing, and enable improved waste-classification management in both nuclear power plants (for the separation of Class A from B/C wastes) and DOE tank farms (for the separation of low level waste (LLW) from high level waste (HLW)). (authors)

  14. Production of rare-earth atomic negative ion beams in a cesium-sputter-type negative ion source

    International Nuclear Information System (INIS)

    The desire to study negative ion structure and negative ion-photon interactions has spurred the development of ion sources for use in research and industry. The many different types of negative ion sources available today differ in their characteristics and abilities to produce anions of various species. Thus the importance of choosing the correct type of negative ion source for a particular research or industrial application is clear. In this study, the results of an investigation on the production of beams composed of negatively-charged rare-earth ions from a cylindrical-cathode-geometry, cesium-sputter-type negative ion source are presented. Beams of atomic anions have been observed for most of the first-row rare-earth elements, with typical currents ranging from hundreds of picoamps to several nanoamps

  15. ION EXCHANGE MODELING FOR REMOVAL OF CESIUM FROM HANFORD WASTE USING SUPERLIG 644 RESIN

    International Nuclear Information System (INIS)

    The expected performance of a proposed ion exchange column using SuperLig(regsign) 644 resin for the removal of cesium from Hanford high level radioactive alkaline waste is discussed. This report represents a final report on the ability and knowledge with regard to modeling the Cesium-SuperLig(regsign) 644 resin ion exchange system. Only the loading phase of the cycle process is addressed within this report. Pertinent bench-scale column tests and batch equilibrium experiments are addressed. The methodology employed and sensitivity analyses are also included (i.e., existing methodology employed is referenced to prior developmental efforts while updated methodology is discussed). Pilot-scale testing is not assessed since no pilot-scale testing was available at the time of this report. Column performance predictions are made considering three selected feed compositions under nominal operating conditions. The sensitivity analyses provided help to identify key parameters that aid in resin procurement acceptance criteria. The methodology and application presented within this report reflect the expected behavior of SuperLig(regsign) 644 resin manufactured at the production-scale (i.e, 250 gallon batch size level). The primary objective of this work was, through modeling and verification based on experimental assessments, to predict the cesium removal performance of SuperLig(regsign) 644 resin for application in the RPP pretreatment facility

  16. ION EXCHANGE MODELING FOR REMOVAL OF CESIUM FROM HANFORD WASTE USING SUPERLIG 644 RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, L

    2004-05-01

    The expected performance of a proposed ion exchange column using SuperLig{reg_sign} 644 resin for the removal of cesium from Hanford high level radioactive alkaline waste is discussed. This report represents a final report on the ability and knowledge with regard to modeling the Cesium-SuperLig{reg_sign} 644 resin ion exchange system. Only the loading phase of the cycle process is addressed within this report. Pertinent bench-scale column tests and batch equilibrium experiments are addressed. The methodology employed and sensitivity analyses are also included (i.e., existing methodology employed is referenced to prior developmental efforts while updated methodology is discussed). Pilot-scale testing is not assessed since no pilot-scale testing was available at the time of this report. Column performance predictions are made considering three selected feed compositions under nominal operating conditions. The sensitivity analyses provided help to identify key parameters that aid in resin procurement acceptance criteria. The methodology and application presented within this report reflect the expected behavior of SuperLig{reg_sign} 644 resin manufactured at the production-scale (i.e, 250 gallon batch size level). The primary objective of this work was, through modeling and verification based on experimental assessments, to predict the cesium removal performance of SuperLig{reg_sign} 644 resin for application in the RPP pretreatment facility.

  17. Electrically switched cesium ion exchange. FY 1996 annual report

    International Nuclear Information System (INIS)

    An electrochemical method for metal ion separations, called Electrically Switched Ion Exchange, is described. Direct oxidation and reduction of an electroactive film attached to an electrode surface is used to load and unload the film with alkali metal cations. The electroactive films under investigation are Ni hexacyanoferrates, which are deposited on the surface by applying an anodic potential to a Ni electrode in a solution containing the ferricyanide anion. Reported film preparation procedures were modified to produce films with improved capacity and stability. Electrochemical behavior of the derivatized electrodes were investigated using cyclic voltammetry and chronocoulometry. The films show selectivity for Cs in concentrated sodium solutions. Raman spectroscopy was used to monitor changes in oxidation state of the film and imaging experiments have demonstrated that the redox reactions are spatially homogenous across the film. Requirements for a bench scale unit were identified

  18. Secondary emission of negative ions and electrons resulting from electronic sputtering of cesium salts

    International Nuclear Information System (INIS)

    Secondary ion emission of negative ions and electrons from alkali salts bombarded with high energy (9 MeV) Ar+++ is discussed. Quite different features are observed according to the nature of the salt investigated (halide or oxygenated). In the case of cesium, the electron emission from halides is characterized by intense electron showers (several hundred electrons) with narrow distributions in intensity and orientation. Conversely, for oxygenated salts, these distributions are broader, much less intense (one order of magnitude), and the ion emission exhibits an dissymmetry, which has never been observed for inorganics. This last result is interpreted in terms of radiolysis of the oxygenated salt, a process well documented for gamma-ray irradiation, but not yet reported in secondary ion emission. (author) 17 refs.; 10 figs

  19. Cesium Ion Exchange Program at the Hanford River Protection Project Waste Treatment Plant

    International Nuclear Information System (INIS)

    The Hanford Waste Treatment and Immobilization Plant (WTP) will use cesium ion exchange to remove Cs-137 from Low Activity Waste (LAW) down to a maximum activity of 0.3 Ci/m3 in the Immobilized LAW (ILAW) product. The WTP Project baseline for cesium ion exchange is the elutable SuperLig(R) 644 (SL-644) resin (registered trademark of IBC Advanced Technologies, Inc., American Fork, UT) or a U. S. Department of Energy (DOE) approved equivalent. SL-644 is solely available through IBC Advanced Technologies. The WTP Project is conducting a three-stage process for selecting and qualifying an alternative ion exchange resin. Resorcinol formaldehyde (RF) is being pursued as a potential alternative to SL-644, to provide a backup resin supply. Resin cost relative to SL-644 is a primary driver. Phase I of the testing plan examined the viability of RF resin and recommended that a spherical form of RF resin be examined further. Phases II and III, now underway, include batch testing to determine the isotherm of this resin, kinetics to address the impacts of bead diameter and high sodium feed levels on processing Hanford waste with the resin, and multicycle column testing to determine how temperature and chemical cycling affects waste processing. Phases II and III also examine resin performance against simulated WTP feeds, radiolytic and thermal stability, and scale-up to pilot scale performance. We will discuss early results obtained from Phase II testing here

  20. Mass analysis of cesium ion induced fragmentation of C/sub 60/

    International Nuclear Information System (INIS)

    Results of Cs ion induced C/sub 60/ fragmentation in source of negative ions by cesium sputtering (SNICS) from 5 MeV Tandem accelerator are presented. The mass analysis was performed from bending magnet. Mass spectra of C/sub 60/ fragments are compared with that of graphite under similar conditions. Yield of carbon clusters for both cases is plotted for Cs ion energy range of 2-5 keV. It is observed that heavier clusters appear in the case of C/sub 60/. Intensity of C/sub 2/ is much higher in comparison with other clusters for both C/sub 60/ and graphite due to difference in their bond energies. Prominence of C/sub 2/ yield confirms formation mechanism of C/sub 60/ by addition of C/sub 2/ route. (author)

  1. Ion exchange removal of cesium from simulated and actual supernate from Hanford tanks 241-SY-101 and 241-SY-103

    International Nuclear Information System (INIS)

    Pacific Northwest Laboratory (PNL), in conjunction with the Process Chemistry and Statistics Section of Westinghouse Hanford Company (WHC), conducted this study as part of the Supernatant Treatment Development Task for the Initial Pretreatment Module (IPM) Applied Engineering Project. The study assesses the performance of the CS-100 ion exchange material for removing cesium from simulated and actual alkaline supernate from Hanford tanks 241-SY-101 and 241-SY-103. The objective of these experiments is to compare the cesium ion exchange loading and elution profiles of actual and simulated wastes. Specific experimental objectives include (1) demonstration of decontamination factors (DF) for cesium removal, 92) verification of simulant performance, (3) investigation of waste/exchanger chemistry, and (4) determination of the radionuclide content of the regenerated CS-100 resin prior to disposal

  2. The Effect of Pressure and Organic Constituents on the Cesium Ion Exchange Performance of IONSIV IE-911

    International Nuclear Information System (INIS)

    This study examined cesium (137Cs) ion exchange of crystalline silicotitanate (CST) in simulated waste solution. In particular, the study focused on the effect of CST pretreatment on the kinetics and extent of cesium adsorption. The test used IONSIV IE-911 (UOP LLC, Molecular Sieves Division, Des Plaines, IL), the engineered form of CST. Pretreatment steps examined include: soaking CST in 2M NaOH solution for three days, exposing CST to 50% relative humidity for one week, flowing organic-containing (saturated) salt solution through a CST packed bed (at 5 cm/min. superficial velocity), or drying CST in air at 100 C for three days. Some tests occurred under 50 and 25 psig of argon. The following conclusions summarize the results. Pretreatment of IE-911 in organic-containing (e.g., tri-n-butyl phosphate, dibutylphosphate, butanol, paraffin and Dow Corning H-10 defoamer) simulated waste or simulated waste yielded a 83% slower rate of cesium adsorption and 56% lower cesium capacity after one week. Pretreatment of IE-911 in 2M caustic solution for 48 hours yielded a slower approach to equilibrium cesium distribution in batch contact tests--7.7 mL/(g*h) during the first 48 hours and 2.4 ml/(g*h) thereafter. Carboxylates and adsorbed carbonates inside the pores likely affect the cesium transport by either increasing the path-length or reducing mass transfer rate. Heating IE-911 as received from the vendor at 100 C for 24 hours significantly degraded its cesium removal performance by a 40.7% reduction in capacity and 43% reduction in sorption rate over one week of testing. Testing determined nearly identical distribution coefficients Kd between lot numbersign 9990-9681-0004 and 9990-9881-0005 (i.e., difference of only 5.6%). Tests measuring water insertion rates into IE-911 show that hydration of the IE-911 does not appear to limit the rate of cesium sorption. Increasing the atmospheric pressure from 0 to 50 psig had no effect on cesium sorption. Note that lower apparent

  3. Preliminiary flowsheet: Ion exchange process for the separation of cesium from Hanford tank waste using Duolite trademark CS-100 resin

    International Nuclear Information System (INIS)

    This preliminary flowsheet document describes an ion exchange process which uses Duolite trademark CS-100 resin to remove cesium from Hanford Tank waste. The flowsheet describes one possible equipment configuration, and contains mass balances based on that configuration with feeds of Neutralized Current Acid Waste, and Double Shell Slurry Feed. Process alternatives, unresolved issues, and development needs are discussed which relate to the process

  4. Removal of cesium ions from contaminated seawater in closed area using adsorptive fiber

    International Nuclear Information System (INIS)

    Insoluble cobalt ferrocyanide (Co-FC) microparticles were impregnated onto a polymer chain grafted onto the surface of a 6-nylon fiber by means of radiation-induced graft polymerization and subsequent precipitation. The resultant Co-FC-impregnated fiber was immersed in either nonradioactive or radioactive cesium (Cs) solution in seawater in an initial Cs concentration range from 60 to 5.0 x 10-4 g-Cs/m3. The adsorption isotherm correlated well with a langmuir-type equation. In addition, the mass-transfer capacity coefficient was determined by fitting the experimental data of the rate of Cs adsorption onto the Co-FC-impregnated fiber to theoretical adsorption curves based on the Cs concentration difference between the bulk and the interface in seawater as a driving force of the overall adsorption rate. Decontamination factors (DFs) as functions of fiber weight and the contact time required for the removal of cesium ions from the contaminated seawater in a closed area were estimated using the above-mentioned values. (author)

  5. Long-pulse operation of a cesium-seeded high-current large negative ion source

    International Nuclear Information System (INIS)

    A high-power large negative ion source has been operated for a long pulse duration. A three-grid single-stage accelerator is used, where the extraction grid is shaped so that the secondary electrons generated on the extraction grid would be prevented from leaking into the acceleration gap. A stable long-pulse arc discharge with an arc power of 100 kW has been obtained over 15 s by balancing an individual arc current flowing through each filament. The cesium-seeded operation is not influenced by a temperature rise of over 100degC of the plasma grid during the long-pulse arc discharge. As a result, the negative ion beam power of 330 kW (91 keV-3.6 A) was produced stably for 10 s from an area of 25 cm x 26 cm, where the current density was 21 mA/cm2 and the negative ion power density was 1.9 kW/cm2. The neutralization efficiency of accelerated negative ions has been measured including the residual positive and negative ion ratios by the water calorimetry of the beam dumps. The result agrees well with the calculation result. (author)

  6. Innovative Highly Selective Removal of Cesium and Strontium Utilizing a Newly Developed Class of Inorganic Ion Specific Media - 16221

    International Nuclear Information System (INIS)

    Highly selective removal of Cesium and Strontium is critical for waste treatment and environmental remediation. Cesium-137 is a beta-gamma emitter and Strontium-90 is a beta emitter with respective half-lives of 30 and 29 years. Both elements are present at many nuclear sites. Cesium and Strontium can be found in wastewaters at Washington State's Hanford Site, as well as in waste streams of many Magnox reactor sites. Cesium and Strontium are found in the Reactor Coolant System of light water reactors at nuclear power plants. Both elements are also found in spent nuclear fuel and in high-level waste (HLW) at DOE sites. Cesium and Strontium are further major contributors to the activity and the heat load. Therefore, technologies to extract Cesium and Strontium are critical for environmental remediation waste treatment and dose minimization. Radionuclides such as Cesium-137 and Strontium-90 are key drivers of liquid waste classification at light water reactors and within the DOE tank farm complexes. The treatment, storage, and disposal of these wastes represents a major cost for nuclear power plant operators, and comprises one of the most challenging technology-driven projects for the DOE Environmental Management (EM) program. Extraction technologies to remove Cesium and Strontium have been an active field of research. Four notable extraction technologies have been developed so far for HLW: solvent extraction, prussian blue, crystalline silico-titanate (CST) and organic ion-exchangers (e.g., resorcinol formaldehyde and SuperLig). The use of one technology over another depends on the specific application. For example, the waste treatment plant (WTP) at Hanford is planning on using a highly-selective organic ion-exchange resin to remove Cesium and Strontium. Such organic ion-exchangers use molecular recognition to selectively bind to Cesium and Strontium. However, these organic ion-exchangers are synthesized using multi-step organic synthesis. The associated cost to

  7. Effect of Temperature on the Removal of Cesium and Strontium Ions from Aqueous Solutions Using Zeolite A

    International Nuclear Information System (INIS)

    Ion exchange experiments between synthetic zeolite A and aqueous solutions of cesium and strontium ions were conducted at constant total ion concentrations of 0.1 N and at different temperatures in the range from 25 to 60 degree C. Thermodynamic equilibrium constants, calculated from the corresponding Kielland's plots, were used for the calculation of . δG degree δH degree and δS degree. The obtained data indicated that zeolite A exhibits higher affinity for Cs+ and Sr+2 ions from solution than host Na+ ions

  8. IN VITRO MASS-SCREENING OF LACTIC ACID BACTERIA AS POTENTIAL BIOSORBENTS OF CESIUM AND STRONTIUM IONS

    OpenAIRE

    Hideki Kinoshita; Yuka Sato1; Fumika Ohtake; Mitsuharu Ishida; Toshikazu Komoda; Haruki Kitazawa; Tadao Saito; Kazuhiko Kimura

    2015-01-01

    Many radionuclides were scattered by the explosion at the Fukushima Daiichi Nuclear Power Station. We examined whether lactic acid bacteria (LAB) can sorb cesium ions (Cs+) and strontium ions (Sr2+) for radioprotection. Many strains showed biosorption to Cs+ and Sr2+ using an in vitro mass-screening although each strain showed different sorption. We selected MYU 111, MYU 758, and MYU 759 strains that showed especially high biosorption to Cs+ and/or Sr2+. MYU 111 was identified as Lactobacillu...

  9. Ion Exchange Modeling Of Cesium Removal From Hanford Waste Using Spherical Resorcinol-Formaldehyde Resin

    International Nuclear Information System (INIS)

    This report discusses the expected performance of spherical Resorcinol-Formaldehyde (RF) ion exchange resin for the removal of cesium from alkaline Hanford radioactive waste. Predictions of full scale column performance in a carousel mode are made for the Hot Commissioning, Envelope B, and Subsequent Operations waste compositions under nominal operating conditions and for perturbations from the nominal. Only the loading phase of the process cycle is addressed in this report. Pertinent bench-scale column tests, kinetic experiments, and batch equilibrium experiments are used to estimate model parameters and to benchmark the ion-exchange model. The methodology and application presented in this report reflect the expected behavior of spherical RF resin manufactured at the intermediate-scale (i.e., approximately 100 gallon batch size; batch 5E-370/641). It is generally believed that scale-up to production-scale in resin manufacturing will result in similarly behaving resin batches whose chemical selectivity is unaffected while total capacity per gram of resin may vary some. As such, the full-scale facility predictions provided within this report should provide reasonable estimates of production-scale column performance.

  10. Kinetic studies on the removal of cesium and strontium ions from aqueous solutions using prepared zeolite-A

    International Nuclear Information System (INIS)

    Preparation and characterization of zeolite-A exchanger were carried out for kinetic studies on the removal of cesium and strontium ions from aqueous solutions. Ion exchange experiments were constant ion-concentration and different temperatures in the range from 25 c degree to 60± c degree. Analysis of the respective rate data in accordance with Hellferich model was performed for the calculation of effective diffusion coefficient (Di), activation energy (Ea) and entropy changes (ΔS) of the exchange process of both ions. A simplified first-order kinetic model was achieved to interpret the kinetic data and the effect of temperature on the overall rate constant (K) of adsorption for both ions was studied. The obtained data indicated that prepared zeolite-A exhibited higher affinity for Cs+ ions from their aqueous solutions than the host Na+ ion. The amount adsorbed of cesium ions (mg/g) is much lower than that of zeolite-A. The amount adsorbed of both studied increases by increasing temperature

  11. Preliminary Ion Exchange Modeling for Removal of Cesium from Hanford Waste Using SuperLig 644 Resin

    International Nuclear Information System (INIS)

    A proposed facility is being designed for the immobilization of Hanford high-level radioactive waste. One unit process in the facility is designed to remove radioactive cesium by ion-exchange from the strongly alkaline aqueous phase. A resin specifically designed with high selectivity of cesium under alkaline conditions is being investigated. The resin also is elutable under more acidic conditions. The proposed design of the facility consists of two sets of two packed columns placed in series (i.e., a lead column followed by a lag (guard) column configuration). During operation, upon reaching a specified cesium concentration criterion at the exit of the lag column, operation is switched to the second set of lead and lag columns. The cesium-loaded lead column is processed (i.e., washed and eluted) and switched to the lag position. the previous lag column is then placed in the lead position (without eluting) and the system is ready for use in the next cycle. For a well designed process, the loading and elution processes result in significant volume reductions in aqueous high-level waste

  12. Preliminary Ion Exchange Modeling for Removal of Cesium from Hanford Waste Using SuperLig 644 Resin

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, L.L.

    2000-08-23

    A proposed facility is being designed for the immobilization of Hanford high-level radioactive waste. One unit process in the facility is designed to remove radioactive cesium by ion-exchange from the strongly alkaline aqueous phase. A resin specifically designed with high selectivity of cesium under alkaline conditions is being investigated. The resin also is elutable under more acidic conditions. The proposed design of the facility consists of two sets of two packed columns placed in series (i.e., a lead column followed by a lag (guard) column configuration). During operation, upon reaching a specified cesium concentration criterion at the exit of the lag column, operation is switched to the second set of lead and lag columns. The cesium-loaded lead column is processed (i.e., washed and eluted) and switched to the lag position. the previous lag column is then placed in the lead position (without eluting) and the system is ready for use in the next cycle. For a well designed process, the loading and elution processes result in significant volume reductions in aqueous high-level waste.

  13. Crystalline silicotitanates--new ion exchanger for selective removal of cesium and strontium from radwastes

    International Nuclear Information System (INIS)

    A new class of inorganic ion exchange material called crystalline silicotitanates (CST) has been developed for radioactive waste treatment in a collaborative effort between Sandia National Laboratories and Texas A ampersand M University. The Sandia National Laboratories Laboratory Directed Research and Development program provided the initial funding for this effort and this report summarizes the rapid progress that was achieved. A wide range of compositions were synthesized, evaluated for cesium (Cs) removal efficiency, and a composition called TAM-5 was developed that exhibits high selectivity and affinity for Cs and strontium (Sr). Tests show it can remove parts per million concentrations of Cs+ from highly alkaline, high-sodium, simulated radioactive waste solutions modeled after those at Hanford, Oak Ridge, and Savannah River. In experiments with solutions that simulate highly alkaline Hanford defense wastes, the crystalline silicotitanates exhibit distribution coefficients for Cs+ of greater than 2,000 ml/g, and distribution coefficients greater than 10,000 ml/g for solutions adjusted to a pH between 1 and 10. In addition, the CSTs were found to exhibit distribution coefficients for Sr+ greater than 100,000 ml/g and for plutonium of 2,000 ml/g from simulated Hanford waste. The CST crystal structure was determined and positions of individual atoms identified using x-ray and neutron diffraction. The structural information has permitted identification of the ion exchange sites and provided insights into the strong effect of pH on Cs ion exchange. Information on the synthesis, composition, and structure of CST is considered proprietary and is not discussed in this report

  14. Separation of cesium from acid ILW-Purex solutions by sorption on inorganic ion exchangers

    International Nuclear Information System (INIS)

    The separation of cesium by use of the inorganic ion exchanger ammonium molybdatophosphate from nitric acid solutions of intermediate level waste (ILW) from reprocessing of spent fuel elements according to the PUREX PROCESS has been demonstrated. Other inorganic exchange materials have shown high sorption values only for certain pH ranges: ammonium hexacyano cobaltous ferrate (pH 12, 35 g Cs/kg), potassium hexacyano nickel ferrate (pH 10, 30 g Cs/kg), zirconium phosphate (pH 7, 100 g Cs/kg), titanium phosphate (pH 7, 15 g Cs/kg), antimony pentoxide (pH 2, 30 g Cs/kg) and titanium oxide (pH 7, 1 g Cs/kg). Except for high salt loading of 3.6 M NaNO3, a significant loss of capacities usually occurs; this does not allow the use of these exchangers. However, ammonium molybdatophosphate shows excellent performance with high salt loadings and in a broad pH-range from pH 9 to conc. HNO3 with a breakthrough-capacity of 60 g Cs/kg. (orig.)

  15. Enrichment and isolation of Flavobacterium strains with tolerance to high concentrations of cesium ion.

    Science.gov (United States)

    Kato, Souichiro; Goya, Eri; Tanaka, Michiko; Kitagawa, Wataru; Kikuchi, Yoshitomo; Asano, Kozo; Kamagata, Yoichi

    2016-01-01

    Interest in the interaction of microorganisms with cesium ions (Cs(+)) has arisen, especially in terms of their potent ability for radiocesium bioaccumulation and their important roles in biogeochemical cycling. Although high concentrations of Cs(+) display toxic effects on microorganisms, there have been only limited reports for Cs(+)-tolerant microorganisms. Here we report enrichment and isolation of Cs(+)-tolerant microorganisms from soil microbiota. Microbial community analysis revealed that bacteria within the phylum Bacteroidetes, especially Flavobacterium spp., dominated in enrichment cultures in the medium supplemented with 50 or 200 mM Cs(+), while Gammaproteobacteria was dominant in the control enrichment cultures (in the presence of 50 and 200 mM K(+) instead of Cs(+)). The dominant Flavobacterium sp. was successfully isolated from the enrichment culture and was closely related to Flavobacterium chungbukense with 99.5% identity. Growth experiments clearly demonstrated that the isolate has significantly higher tolerance to Cs(+) compared to its close relatives, suggesting the Cs(+)-tolerance is a specific trait of this strain, but not a universal trait in the genus Flavobacterium. Measurement of intracellular K(+) and Cs(+) concentrations of the Cs(+)-tolerant isolate and its close relatives suggested that the ability to maintain low intracellular Cs(+) concentration confers the tolerance against high concentrations of external Cs(+). PMID:26883718

  16. Development of composite ion exchanger for separation of cesium from high level liquid waste

    International Nuclear Information System (INIS)

    137Cs (t1/2 = 30 years) is one of the major radioisotope present in high level liquid waste (HLLW) generated during the reprocessing of nuclear fuel. Separation of 137Cs from HLLW results in reduction of personal radiation exposure during the conditioning, transportation, storage and disposal. In addition, 137Cs has enormous application as a radiation source in food preservation, sterilization of medical products, brachytherapy, blood irradiation, hygienization of sewage sludge etc. Ammonium molybdophosphate (AMP), an inorganic ion exchanger, has high selectivity and high exchange capacity for Cs. It exits as microcrystalline powder which is not amenable for column operation. ALIX is a composite material in which AMP is physically blended with inert polymeric substrate to improve its column property, exchange kinetics and increase its mechanical strength. The observed excellent properties of the composite are attributed to its engineered structure which is formed during its production. SEM analysis of ALIX shows that AMP crystals embedded in the cavities are not covered by the polymer which greatly enhances its availability for cesium exchange. The highly porous structure of the composite having 49% void volume facilitates faster kinetics of exchange of Cs from the aqueous phase and increased rate of reaction with alkali required during its dissolution

  17. possibilities of isotope separation of radioactive cesium by ion cyclotron resonance

    International Nuclear Information System (INIS)

    The transmutation of radioactive wastes is of high interest in order to reduce as much as possible the difficulties induced by their storage. In the case of radioactive cesium waste, cesium 137 which presents a short life time (30 years) is difficult to handle due to its high thermal load and and radiation level; cesium 135 is a long life time isotope with high mobility in storage glasses. As the processes of transmutation are different for cesium 135 and cesium 137 and as the neutron consumption is very high, it would be necessary to proceed to a preliminary isotope separation and it would not be worth to transmute the stable 133 isotope of cesium. Peculiar problems linked with cesium physico-chemical properties such as ionisation rat, vapour pressure, cooling of the components of the separation elements, especially the collector part, are discussed. It is shown that a high density plasma (1012 cm -3), with low ionic temperature (1 eV), good for isotope separation, can be achieved easily. It must be noticed that the cooling with water has to be avoided due to chemical reactions. After having defined the unitary separative element, different enrichment strategies and arrangements of the separative elements are proposed. An economic estimation with our code RICAN is given. (author)

  18. Preliminary flowsheet: Ion exchange for separation of cesium from Hanford tank waste using resorcinol-formaldehyde resin

    International Nuclear Information System (INIS)

    This preliminary flowsheet document describes an ion exchange process which uses resorcinol-formaldehyde (R-F) resin to remove cesium from Hanford tank waste. The flowsheet describes one possible equipment configuration, and contains mass balances based on that configuration with feeds of Neutralized Current Acid Waste, and Double Shell Slurry Feed. The flowsheet also discusses process alternatives, unresolved issues, and development needs associated with the ion exchange process. It is expected that this flowsheet will evolve as open issues are resolved and progress is made on development needs. This is part of the Tank Waste Remediation Program at Hanford. 26 refs, 6 figs, 25 tabs

  19. Steady State Sputtering Yields and Surface Compositions of Depleted Uranium and Uranium Carbide bombarded by 30 keV Gallium or 16 keV Cesium Ions

    International Nuclear Information System (INIS)

    Depleted uranium that included carbide inclusions was sputtered with 30keV gallium ions or 16kev cesium ions to depths much greater than the ions’ range, i.e. using steady state sputtering. The recession of both the uranium’s and uranium carbide’s surfaces and the ion corresponding fluences were used to determine the steady state target sputtering yields of both uranium and uranium carbide, i.e. 6.3 atoms of uranium and 2.4 units of uranium carbide eroded per gallium ion, and 9.9 uranium atoms and 3.65 units of uranium carbide eroded by cesium ions. The steady state surface composition resulting from the simultaneous gallium or cesium implantation and sputter-erosion of uranium and uranium carbide were calculated to be U86Ga14, (UC)70Ga30 and U81Cs9, (UC)79Cs21, respectively.

  20. Steady State Sputtering Yields and Surface Compositions of Depleted Uranium and Uranium Carbide bombarded by 30 keV Gallium or 16 keV Cesium Ions.

    Energy Technology Data Exchange (ETDEWEB)

    Siekhaus, W. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Teslich, N. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Weber, P. K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-10-23

    Depleted uranium that included carbide inclusions was sputtered with 30-keV gallium ions or 16-kev cesium ions to depths much greater than the ions’ range, i.e. using steady-state sputtering. The recession of both the uranium’s and uranium carbide’s surfaces and the ion corresponding fluences were used to determine the steady-state target sputtering yields of both uranium and uranium carbide, i.e. 6.3 atoms of uranium and 2.4 units of uranium carbide eroded per gallium ion, and 9.9 uranium atoms and 3.65 units of uranium carbide eroded by cesium ions. The steady state surface composition resulting from the simultaneous gallium or cesium implantation and sputter-erosion of uranium and uranium carbide were calculated to be U₈₆Ga₁₄, (UC)₇₀Ga₃₀ and U₈₁Cs₉, (UC)₇₉Cs₂₁, respectively.

  1. New separation techniques of cesium by redox type ion exchange materials

    International Nuclear Information System (INIS)

    RIECS method, new cesium separation method, was developed in which a porous strong base anionic exchanger with copper ferrocyanide (CuFC) and inhibitor were used. Cesium could be separated from the high concentration nitric solution. By developing new impregnation method, large amount of CuFC was impregnated into the micropolar porous resin and silica gel pores. KFC adhered to outside of pores was recovered. Good complex with CuFC was prepared by use of copper chloride in ethyl alcohol solution. The adsorption ratio of cesium increased radically to 80% level in the very small range of hydrazine concentration 1.7 to 2.4x10-4M. The adsorption-desorption ratio of cesium did not decrease by repeating it seven times. The glassificated materials decreased large amount of γ-ray unless increase of volume could be produced by built RIECS method in the high level waste processing system. (S.Y.)

  2. Development of a carousel ion-exchange process for removal of cesium-137 from alkaline nuclear waste

    International Nuclear Information System (INIS)

    A systematic model-based approach is used for development of an efficient carousel ion-exchange process for the selective removal of radioactive 137Cs+ from alkaline nuclear waste solutions. Equilibrium data for two resorcinol-formaledhyde (R-F) cation-exchange resins are correlated by an empirical equation of the Freundlich-Langmuir type over cesium/sodium concentration ratios of 10-9 to 10-2 and sodium concentrations of 1 to 6 N. The standard deviations are 3.5 and 6.6%, respectively. The data cannot be accurately described by mass action equations. A detailed rate model, developed in this study for the periodic countercurrent multicolumn operation of carousel systems, is used with the equilibrium correlations to simulate cesium breakthrough curves from R-F resin columns. Results show that accuracy of the predicted breakthrough curves are directly related to the accuracy of the isotherm data and correlations. Cesium breakthrough position is generally predicted to within 5% or less for 10 of 13 runs over linear superficial velocities of 0.16 to 8.8 cm/min, column lengths of 3.14 to 118.5 cm, and particle radii of 145 to 200 microm. One run shows later breakthrough than predicted as a result of a low potassium concentration in the feed. Two other runs show early breakthroughs as a result of channeling in poorly packed columns of a carousel system. Despite the channeling, strong thermodynamic self-sharpening effects helped establish constant pattern waves in the downstream columns. A case study for a pilot-scale carousel unit shows that 100% utilization of cesium capacity and maximum throughput can be achieved while containing the mass transfer zone within the downstream columns. Since intraparticle diffusion controls spreading of the breakthrough curves, reducing the particle radius from 200 to 145 microm increases throughput by 40%

  3. 3-(Dicyanomethylidene)indan-1-one-Functionalized Calix[4]arene-Calix[4]pyrrole Hybrid: An Ion-Pair Sensor for Cesium Salts.

    Science.gov (United States)

    Yeon, Yerim; Leem, Soojung; Wagen, Corin; Lynch, Vincent M; Kim, Sung Kuk; Sessler, Jonathan L

    2016-09-01

    A chromogenic calix[4]arene-calix[4]pyrrole hybrid ion pair receptor bearing an indane substituent at a β-pyrrolic position has been prepared. On the basis of solution-phase UV-vis spectroscopic analysis and (1)H NMR spectroscopic studies carried out in 10% methanol in chloroform, receptor 1 is able to bind only cesium ion pairs (e.g., CsF, CsCl, and CsNO3) but not the constituent cesium cation (as its perchlorate salt) or the F(-), Cl(-), or NO3(-) anions (as the tetrabutylammonium salts). It thus displays rudimentary AND logic gate behavior. Receptor 1 shows a colorimetric response to cesium ion pairs under conditions of solid-liquid (nitrobenzene) and liquid-liquid (D2O-nitrobenzene-d5) extraction. PMID:27533478

  4. Elucidating the structures and cooperative binding mechanism of cesium salts to the multitopic ion-pair receptor through density functional theory calculations.

    Science.gov (United States)

    Sadhu, Biswajit; Sundararajan, Mahesh; Velmurugan, Gunasekaran; Venuvanalingam, Ponnambalam

    2015-09-21

    Designing new and innovative receptors for the selective binding of radionuclides is central to nuclear waste management processes. Recently, a new multi-topic ion-pair receptor was reported which binds a variety of cesium salts. Due to the large size of the receptor, quantum chemical calculations on the full ion-pair receptors are restricted, thus the binding mechanisms are not well understood at the molecular level. We have assessed the binding strengths of various cesium salts to the recently synthesized multi-topic ion-pair receptor molecule using density functional theory based calculations. Our calculations predict that the binding of cesium salts to the receptor predominantly occurs via the cooperative binding mechanism. Cesium and the anion synergistically assist each other to bind favorably inside the receptor. Energy decomposition analysis on the ion-pair complexes shows that the Cs salts are bound to the receptor mainly through electrostatic interactions with small contribution from covalent interactions for large ionic radius anions. Further, QTAIM analysis characterizes the importance of different inter-molecular interactions between the ions and the receptor inside the ion-pair complexes. The role of the crystallographic solvent molecule contributes significantly by ~10 kcal mol(-1) to the overall binding affinities which is quite significant. Further, unlike the recent molecular mechanics (MM) calculations, our calculated binding affinity trends for various Cs ion-pair complexes (CsF, CsCl and CsNO3) are now in excellent agreement with the experimental binding affinity trends. PMID:26227949

  5. Comparison of inorganic ion exchange materials for removing cesium, strontium, and transuranic elements from K-basin water

    International Nuclear Information System (INIS)

    The work presented in this report was conducted by the Pacific Northwest National Laboratory (PNNL) under the Efficient Separations and Crosscutting Program (ESP), Office of Science and Technology, U.S. Department of Energy (DOE). The objective of this work was to investigate radionuclide uptake by several newly produced ion exchange materials under actual waste conditions, and to compare the performance of those materials with that of commercially available ion exchangers. The equilibrium uptake data presented in this report are useful for identifying potential materials that are capable of removing cesium and strontium from 105-KE Basin water. The data show the relative selectivities of the ion exchange materials under similar operating conditions. Additional flow studies are needed to predict material capacities and to develop complete ion exchange process flow sheets. The materials investigated in this study include commercially available ion exchangers such as IONSIV reg-sign IE-911 (manufactured by UOP), clinoptilolite (a naturally occurring zeolite), and materials produced on an experimental basis by AlliedSignal (biotites and nonatitanates), 3M (hexacyanoferrates), Selion Technologies, Inc. (hexacyanoferrates and titanates), and Texas A ampersand M University (pharmacosiderites, biotites, and nonatitanates). In all, the performance of 14 ion exchange materials was evaluated at two solution-to-exchanger mass ratios (i.e., 104 and 105) using actual 105-KE Basin water. Evaluation consisted of determining cesium and strontium batch distribution coefficients, loading, and decontamination factors. Actual 105-KE Basin water was obtained from a sample collected during the sludge dissolution work conducted by PNNL in FY 1996. This sample was taken from the bottom of the basin and contained significantly higher concentrations of the radioactive constituents than do samples taken from the top of the basin

  6. Comparison of inorganic ion exchange materials for removing cesium, strontium, and transuranic elements from K-basin water

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.N.; Bontha, J.R.; Carson, K.J.; Elovich, R.J.; DesChane, J.R.

    1997-10-01

    The work presented in this report was conducted by the Pacific Northwest National Laboratory (PNNL) under the Efficient Separations and Crosscutting Program (ESP), Office of Science and Technology, U.S. Department of Energy (DOE). The objective of this work was to investigate radionuclide uptake by several newly produced ion exchange materials under actual waste conditions, and to compare the performance of those materials with that of commercially available ion exchangers. The equilibrium uptake data presented in this report are useful for identifying potential materials that are capable of removing cesium and strontium from 105-KE Basin water. The data show the relative selectivities of the ion exchange materials under similar operating conditions. Additional flow studies are needed to predict material capacities and to develop complete ion exchange process flow sheets. The materials investigated in this study include commercially available ion exchangers such as IONSIV{reg_sign} IE-911 (manufactured by UOP), clinoptilolite (a naturally occurring zeolite), and materials produced on an experimental basis by AlliedSignal (biotites and nonatitanates), 3M (hexacyanoferrates), Selion Technologies, Inc. (hexacyanoferrates and titanates), and Texas A&M University (pharmacosiderites, biotites, and nonatitanates). In all, the performance of 14 ion exchange materials was evaluated at two solution-to-exchanger mass ratios (i.e., 10{sup 4} and 10{sup 5}) using actual 105-KE Basin water. Evaluation consisted of determining cesium and strontium batch distribution coefficients, loading, and decontamination factors. Actual 105-KE Basin water was obtained from a sample collected during the sludge dissolution work conducted by PNNL in FY 1996. This sample was taken from the bottom of the basin and contained significantly higher concentrations of the radioactive constituents than do samples taken from the top of the basin.

  7. Application of inorganic adsorbents and ion exchange resins for decontamination of solutions from cesium and strontium radionuclides

    International Nuclear Information System (INIS)

    Adsorption characteristics of different types of organic ion exchange resins and inorganic adsorbents have been investigated with respect to cesium and strontium ions. Studies have been performed through the determination of distribution coefficients of 137Cs and 85Sr tracers on those ion exchangers in sodium and calcium-containing solutions. Among the ion exchangers under investigation the ferrocyanide-based adsorbents appeared to reveal the highest selectivity with respect to Cs (Kd = (2--9) x 104 cm3/g in 1 mole/l NaNO3 solution), the selectivity of the others being 1--2 orders of magnitude less. The highest selectivity with respect to Sr has been observed with synthetic zeolites (Kd = 103--104) and hydrated manganese dioxide-based adsorbents (Kd = 1.0 x 103--3.8 x 104). The influence of calcium ions on the adsorption of strontium is mentioned to be much stronger than that of sodium ions. As the result of the studies, the ion exchangers suitable for decontaminating industrial reservoir water from 137Cs and 90Sr have been identified. Precipitation of calcium and magnesium ions, e.g. in carbonates, from feed water prior to Sr adsorption is shown to be required to gain the efficient removal of Sr. Resultant data on industrial reservoir water decontamination in the course of pilot plant tests are given and discussed

  8. A new ion selective electrode for cesium (I) based on calix[4]arene-crown-6 compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ramanjaneyulu, P.S. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400094 (India); Kumar, Abha Naveen [Bio-Organic Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400094 (India); Sayi, Y.S. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400094 (India); Ramakumar, K.L., E-mail: klram@barc.gov.in [Radiochemistry and Isotope Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400094 (India); Nayak, S.K.; Chattopadhyay, S. [Bio-Organic Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400094 (India)

    2012-02-29

    Highlights: Black-Right-Pointing-Pointer First report on Cs(I)-ISE employing 25,27-bis(1-octyloxy)calix[4]arene-crown-6. Black-Right-Pointing-Pointer Higher sensitivity and selectivity achieved by minimizing trans-membrane fluxes. Black-Right-Pointing-Pointer 10 months life time is longest reported so far for membrane based Cs-ISE. Black-Right-Pointing-Pointer Cesium is chemically toxic displaces potassium from muscles and red blood cells. Black-Right-Pointing-Pointer Its monitoring in environment is essential. - Abstract: A polyvinylchloride (PVC) based liquid membrane ion selective electrode (ISE) for cesium has been developed. 25,27-Dihydroxycalix[4]arene-crown-6 (L1), 5,11,17,23-tetra-tert-butyl-25,27-dimethoxycalix[4]arene-crown-6 (L2) and 25,27-bis(1-octyloxy)calix[4]arene-crown-6 (L3) were investigated for their use as ionophores. The cation exchange resin DOWEX-50W was used to maintain low activity Cs{sup +} in inner filling solution to improve the performance. The best response for cesium was observed with L3 along with optimized membrane constituents and composition. Excellent Nernstian response (56.6 mV/decade of Cs(I)) over the concentration range 10{sup -7} to 10{sup -2} M of Cs(I) was obtained with a fast response time of less than 10 s. Detection limit for Cs(I) using the present ISE is 8.48 Multiplication-Sign 10{sup -8} M Cs(I). Separate solution method (SSM) was applied to ascertain the selectivity for Cs(I) over alkali, alkaline earth and transition metal ions. The response of ISE for Cs(I) was fairly constant over the pH range of 4-11. The lifetime of the electrode is 10 months which is the highest life for any membrane based Cs-ISE so far developed. The concentration of cesium ion in two simulated high level active waste streams was determined and results agreed well with those obtained independently employing AAS.

  9. Multiple Ion Exchange Column Runs for Cesium and Technetium Removal from AW-101 Waste Sample

    International Nuclear Information System (INIS)

    The River Protection Project -Waste Treatment Plant (RPP--WTP) will be performing cesium removal from Hanford tank waste supernatants using SuperLig 644 resin. These elutable resins will be used multiple times to process large volumes of radioactive waste samples and will be subjected to chemical and radiation degradation during use at the waste treatment plant (WTP). The RPP--WTP process design assumes that resin batches can be used a minimum of 10 cycles before the resin must be replaced due to degradation. The effects of radiation and chemical degradation on SuperLig 644 and 639 resins were separately studied in the past under static conditions, i.e., in contact with air, water, and simulated waste solutions. To determine the chemical degradation effects under dynamic or column conditions, Battelle, Pacific Northwest National Laboratory (PNNL), and IBC Advanced Technologies conducted multiple load/elute/regenerate cycles with simulated Hanford waste samples. Savannah River Technology Center (SRTC) was contracted to demonstrate the performance of SuperLig 644 and 639 resins to treat repetitively radioactive waste solutions. Six cycles of loading, elution, and regeneration were performed to remove cesium from a Hanford waste sample. Five load/elute/regenerate cycles were carried out to remove technetium from cesium-depleted effluent solutions. The multiple load/elute/regenerate cycles demonstrated that cesium and technetium can be effectively removed from a sample using SuperLig 644 and 639 resins. The percent cesium removal was greater than 99.99 per cent for each of the six cycles

  10. Performance evaluation of 24 ion exchange materials for removing cesium and strontium from actual and simulated N-Reactor storage basin water

    International Nuclear Information System (INIS)

    This report describes the evaluation of 24 organic and inorganic ion exchange materials for removing cesium and strontium from actual and simulated waters from the 100 Area 105 N-Reactor fuel storage basin. The data described in this report can be applied for developing and evaluating ion exchange pre-treatment process flowsheets. Cesium and strontium batch distribution ratios (Kd's), decontamination factors (DF), and material loadings (mmol g-1) are compared as a function of ion exchange material and initial cesium concentration. The actual and simulated N-Basin waters contain relatively low levels of aluminum, barium, calcium, potassium, and magnesium (ranging from 8.33E-04 to 6.40E-05 M), with slightly higher levels of boron (6.63E-03 M) and sodium (1.62E-03 M). The 137Cs level is 1.74E-06 Ci L-1 which corresponds to approximately 4.87E-10 M Cs. The initial Na/Cs ratio was 3.33E+06. The concentration of total strontium is 4.45E-06 M, while the 90Sr radioactive component was measured to be 6.13E-06 Ci L-1. Simulant tests were conducted by contacting 0.067 g or each ion exchange material with approximately 100 mL of either the actual or simulated N-Basin water. The simulants contained variable initial cesium concentrations ranging from 1.00E-04 to 2.57E- 10 M Cs while all other components were held constant. For all materials, the average cesium Kd was independent of cesium concentration below approximately 1.0E-06 M. Above this level, the average cesium Kd values decreased significantly. Cesium Kd values exceeding 1.0E+07 mL g-1 were measured in the simulated N-Basin water. However, when measured in the actual N-Basin water the values were several orders of magnitude lower, with a maximum of 1.24E+05 mL g-1 observed

  11. Performance evaluation of 24 ion exchange materials for removing cesium and strontium from actual and simulated N-Reactor storage basin water

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.N.; Carson, K.J.; DesChane, J.R.; Elovich, R.J.

    1997-09-01

    This report describes the evaluation of 24 organic and inorganic ion exchange materials for removing cesium and strontium from actual and simulated waters from the 100 Area 105 N-Reactor fuel storage basin. The data described in this report can be applied for developing and evaluating ion exchange pre-treatment process flowsheets. Cesium and strontium batch distribution ratios (K{sub d}`s), decontamination factors (DF), and material loadings (mmol g{sup -1}) are compared as a function of ion exchange material and initial cesium concentration. The actual and simulated N-Basin waters contain relatively low levels of aluminum, barium, calcium, potassium, and magnesium (ranging from 8.33E-04 to 6.40E-05 M), with slightly higher levels of boron (6.63E-03 M) and sodium (1.62E-03 M). The {sup 137}Cs level is 1.74E-06 Ci L-{sup 1} which corresponds to approximately 4.87E-10 M Cs. The initial Na/Cs ratio was 3.33E+06. The concentration of total strontium is 4.45E-06 M, while the {sup 90}Sr radioactive component was measured to be 6.13E-06 Ci L{sup -1}. Simulant tests were conducted by contacting 0.067 g or each ion exchange material with approximately 100 mL of either the actual or simulated N-Basin water. The simulants contained variable initial cesium concentrations ranging from 1.00E-04 to 2.57E- 10 M Cs while all other components were held constant. For all materials, the average cesium K{sub d} was independent of cesium concentration below approximately 1.0E-06 M. Above this level, the average cesium K{sub d} values decreased significantly. Cesium K{sub d} values exceeding 1.0E+07 mL g{sup -1} were measured in the simulated N-Basin water. However, when measured in the actual N-Basin water the values were several orders of magnitude lower, with a maximum of 1.24E+05 mL g{sup -1} observed.

  12. Development of heat conduction type cesium injection device for negative-ion source for JT-60U

    International Nuclear Information System (INIS)

    In the negative-ion source for JT-60U, cesium (Cs) vapor is introduced into an arc chamber to enhance negative-ion production rate. Conventional Cs injection devices were often broken by high voltage noises occurred during the ion beam acceleration. To make higher noise-resistant, the development of a newly heat conduction type Cs injection device and improvement of heater power supply to prevent heater break-down, were required. To repair easily the Cs injection device after the heater was break-down, a new structure of an inlet tube was proposed to be settled no heater located in the vacuum area and to be heated up a given temperature through thermal conduction from the heated part of the tube located the atmospheric pressure area. Thermal characteristics, such as temperature rise time, heat losses and temperature distributions of the tube were calculated for some types of the tube. Based on these calculations, a new device of the heat conduction type inlet tube was designed and manufactured. The verification tests of the device showed that the experimental results were agreed well with the calculated ones. After the test, the new Cs inlet device was set onto the negative-ion source for JT-60U. The heater power supply was also modified to be cut off during beam acceleration which makes high voltage noises. As a result of these improvements, the heating system for the Cs injection devices is now working well without break-down of heaters. (author)

  13. Treatment of low-level radioactive cesium-137 and technetium-99 liquid wastes by inorganic ion-exchangers

    International Nuclear Information System (INIS)

    This study has been directed towards the testing and evaluation of selected inorganic ion-exchangers that are inexpensive and suitable for the conditioning and disposal of radioactive wastes. The experiments were based on sorption characteristics of inorganic ion-exchange materials and their ability to retain radionuclides. The sorption efficiency of cesium-137 and technetium-99 on exchangers was tested under various conditions including the effect of pH, equilibrium time, temperature and concentration for bentonite, kaolinite, sand and sandy soil, which are classified as natural inorganic exchangers. Titanium dioxide, zeolite, antimony pentioxide and hydrated antimony pentoxide (HAP) were used as synthetic inorganic exchangers. This report also includes a basic study of the cementation process along with the measurement of several important waste from properties such as physical stability, compressive strength and leachability. The percentage sorption efficiency of cesium-137 was found to be 99, 98, 88, 87, 86 and 85 respectively for zeolite, kaolinite, antimony pentoxide, sandy soil, sand and HAP, at 25-500C, pH range 3-9 and 10-20 minutes contact time. The sorption of technetium-99 on antimony pentoxide was 80-90, at 250 C, pH range 1-9 and 5 days contact time. The physical stability tests indicated that all specimens had good homogeneity. Percentages of weight-loss after 28 day cure times at ambient room temperature were in the range of 7-15, 2-6, 6-9, 3-10 and 4-5 for bentonite, kaolinite, zeolite, titanium dioxide and sand respectively. The compressive strength of conditioned waste form consisting of various simulated waste compositions are reported. For the purpose of this study, an arbitrary compressive strength value of 150 kgm/cm2 was established. The proper percentage composition of cemented wastes were 19, 24, 25, 45 and 54 for bentonite, kaolinite, zeolite, titanium dioxide and sand respectively. The leachability for kaolinite cemented waste containing

  14. Synthesis and characterization of cesium molybdo vanado phosphate immobilized on platelet SBA-15: An efficient inorganic composite ion-exchanger for gadolinium ion sorption

    Energy Technology Data Exchange (ETDEWEB)

    Aghayan, H., E-mail: hasanaghayan@yahoo.com [Department of Chemistry, Tarbiat Modares University, P.O. Box. 14155-4383, Tehran (Iran, Islamic Republic of); Khanchi, A.R., E-mail: akhanchi@aeoi.org.ir [Nuclear Science and Technology Institute, P.O. Box. 11365-8486, Tehran (Iran, Islamic Republic of); Mahjoub, A.R. [Department of Chemistry, Tarbiat Modares University, P.O. Box. 14155-4383, Tehran (Iran, Islamic Republic of)

    2013-06-01

    A series of cesium molybdo vanado phosphate (CsMVP) supported on platelet SBA-15 (SBA-15–%xCsMVP, x = 20, 30, 40 and 50 wt.%) was synthesized to develop an efficient inorganic composite ion-exchanger for gadolinium ion removal from aqueous solution. The preparation has been carried out using two-step aqueous impregnation methods. The obtained products were characterized by inductively coupled plasma (ICP), XRD, N{sub 2} adsorption–desorption isotherms, scanning electron microscopy (SEM) and FT-IR. In order to examine adsorption behavior of this compound on gadolinium removal, the effect of heteropoly metalate loading, pH, contact time, concentration of metal ion and temperature were investigated under batch system conditions. The SBA-15–30%CsMVP showed maximum adsorption capacity toward gadolinium removal. The results suggested that this methodology provides the general synthesis of supported heteropolymetalate with large surface areas, and ordered nano porous structures that can be used as inorganic composite ion-exchanger for efficient removal of gadolinium ions from aqueous solution.

  15. Comparison or organic and inorganic ion exchange materials for removal of cesium and strontium from Hanford waste

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.N.; Carson, K.J.; DesChane, J.R.; Elovich, R.J. [Pacific Northwest National Lab., Richland, WA (United States)

    1997-10-01

    This work is part of an ESP-CP task to develop and evaluate high-capacity, selective, solid extractants for the uptake of cesium, strontium, and technetium (Cs, Sr, and Tc) from nuclear wastes. Pacific Northwest National Laboratory (PNNL) staff, in collaboration with researchers from industry, academia, and national laboratories are investigating these and other novel and commercial ion exchangers for use in nuclear waste remediation of groundwater, HLW, and LLW. Since FY 1995, experimental work at PNNL has focused on small-scale batch distribution (K{sub d}) testing of numerous solid sorbents with actual and simulated Hanford wastes, chemical and radiolytic stability of various organic ion exchanger resins, bench-scale column ion exchange testing in actual and simulated Complexant Concentrate (CC) and Neutralized Current Acid Waste (NCAW), and Tc and Sr removal from groundwater and LLW. In addition, PNNL has continued to support various site demonstrations at the Idaho National Engineering Laboratory, Savannah River Site, West Valley Nuclear Services, Hanford N-Springs, and Hanford N-Basin using technologies developed by their industrial partners. This summary will focus on batch distribution results from the actual waste tests. The data collected in these development and testing tasks provide a rational basis for the selection and direct comparison of various ion exchange materials in simulated and actual HLW, LLW, and groundwater. In addition, prediction of large-scale column loading performance for the materials tested is possible using smaller volumes of actual waste solution. The method maximizes information while minimizing experimental expense, time, and laboratory and process wastes.

  16. Selective removal of cesium(I), strontium(II), barium(II) and lead(II) with ionizable lariat ethers in ion flotation process

    International Nuclear Information System (INIS)

    The work deals an application of ion flotation for selective removal of ion cesium(I), strontium(II), barium(II) and lead(II) from: (a) dilute and slightly acidic (pH=4 - 6) aqueous solutions of those ions at concentration -5 M; (b) radioactive sewages and waste solutions. The collective removal and separation of Cs(I), Sr(II), Ba(II), Pb(II) with macrocycle compounds, e.g. ionizable lariat ethers and non-ionizable foaming agent is shown

  17. Hybrid Organic/Inorganic Materials Depth Profiling Using Low Energy Cesium Ions

    Science.gov (United States)

    Noël, Céline; Houssiau, Laurent

    2016-02-01

    The structures developed in organic electronics, such as organic light emitting diodes (OLEDs) or organic photovoltaics (OPVs) devices always involve hybrid interfaces, joining metal or oxide layers with organic layers. No satisfactory method to probe these hybrid interfaces physical chemistry currently exists. One promising way to analyze such interfaces is to use in situ ion beam etching, but this requires ion beams able to depth profile both inorganic and organic layers. Mono- or diatomic ion beams commonly used to depth profile inorganic materials usually perform badly on organics, while cluster ion beams perform excellently on organics but yield poor results when organics and inorganics are mixed. Conversely, low energy Cs+ beams (quality. This first successful hybrid depth profiling report opens new possibilities for the study of OLEDs, organic solar cells, or other hybrid devices.

  18. Hybrid Organic/Inorganic Materials Depth Profiling Using Low Energy Cesium Ions

    Science.gov (United States)

    Noël, Céline; Houssiau, Laurent

    2016-05-01

    The structures developed in organic electronics, such as organic light emitting diodes (OLEDs) or organic photovoltaics (OPVs) devices always involve hybrid interfaces, joining metal or oxide layers with organic layers. No satisfactory method to probe these hybrid interfaces physical chemistry currently exists. One promising way to analyze such interfaces is to use in situ ion beam etching, but this requires ion beams able to depth profile both inorganic and organic layers. Mono- or diatomic ion beams commonly used to depth profile inorganic materials usually perform badly on organics, while cluster ion beams perform excellently on organics but yield poor results when organics and inorganics are mixed. Conversely, low energy Cs+ beams (quality. This first successful hybrid depth profiling report opens new possibilities for the study of OLEDs, organic solar cells, or other hybrid devices.

  19. Selective Removal Of Strontium And Cesium From Simulated Waste Solution With Titanate Ion-Exchangers In A Filter Cartridge Configurations-12092

    International Nuclear Information System (INIS)

    Experimental results for the selective removal of strontium and cesium from simulated waste solutions with monosodium titanate and crystalline silicotitanate laden filter cartridges are presented. In these proof-of-principle tests, effective uptake of both strontium-85 and cesium-137 were observed using ion-exchangers in this filter cartridge configuration. At low salt simulant conditions, the instantaneous decontamination factor for strontium-85 with monosodium titanate impregnated filter membrane cartridges measured 26, representing 96% strontium-85 removal efficiency. On the other hand, the strontium-85 instantaneous decontamination factor with co-sintered active monosodium titanate cartridges measured 40 or 98% Sr-85 removal efficiency. Strontium-85 removal with the monosodium titanate impregnated membrane cartridges and crystalline silicotitanate impregnated membrane cartridges, placed in series arrangement, produced an instantaneous decontamination factor of 41 compared to an instantaneous decontamination factor of 368 for strontium-85 with co-sintered active monosodium titanate cartridges and co-sintered active crystalline silicotitanate cartridges placed in series. Overall, polyethylene co-sintered active titanates cartridges performed as well as titanate impregnated filter membrane cartridges in the uptake of strontium. At low ionic strength conditions, there was a significant uptake of cesium-137 with co-sintered crystalline silicotitanate cartridges. Tests results with crystalline silicotitanate impregnated membrane cartridges for cesium-137 decontamination are currently being re-evaluated. Based on these preliminary findings we conclude that incorporating monosodium titanate and crystalline silicotitanate sorbents into membranes represent a promising method for the semicontinuous removal of radioisotopes of strontium and cesium from nuclear waste solutions.

  20. SELECTIVE REMOVAL OF STRONTIUM AND CESIUM FROM SIMULATED WASTE SOLUTION WITH TITANATE ION-EXCHANGERS IN A FILTER CARTRIDGE CONFIGURATIONS-12092

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L.; Martin, K.; Hobbs, D.

    2012-01-03

    Experimental results for the selective removal of strontium and cesium from simulated waste solutions with monosodium titanate and crystalline silicotitanate laden filter cartridges are presented. In these proof-of-principle tests, effective uptake of both strontium-85 and cesium-137 were observed using ion-exchangers in this filter cartridge configuration. At low salt simulant conditions, the instantaneous decontamination factor for strontium-85 with monosodium titanate impregnated filter membrane cartridges measured 26, representing 96% strontium-85 removal efficiency. On the other hand, the strontium-85 instantaneous decontamination factor with co-sintered active monosodium titanate cartridges measured 40 or 98% Sr-85 removal efficiency. Strontium-85 removal with the monosodium titanate impregnated membrane cartridges and crystalline silicotitanate impregnated membrane cartridges, placed in series arrangement, produced an instantaneous decontamination factor of 41 compared to an instantaneous decontamination factor of 368 for strontium-85 with co-sintered active monosodium titanate cartridges and co-sintered active crystalline silicotitanate cartridges placed in series. Overall, polyethylene co-sintered active titanates cartridges performed as well as titanate impregnated filter membrane cartridges in the uptake of strontium. At low ionic strength conditions, there was a significant uptake of cesium-137 with co-sintered crystalline silicotitanate cartridges. Tests results with crystalline silicotitanate impregnated membrane cartridges for cesium-137 decontamination are currently being re-evaluated. Based on these preliminary findings we conclude that incorporating monosodium titanate and crystalline silicotitanate sorbents into membranes represent a promising method for the semicontinuous removal of radioisotopes of strontium and cesium from nuclear waste solutions.

  1. Chemical and radiation stability of SuperLig reg-sign 644, resorcinol-formaldehyde, and CS-100 cesium ion exchange materials

    International Nuclear Information System (INIS)

    At the request of the Initial Pretreatment Module Project within Westinghouse Hanford Company, Pacific Northwest Laboratory (PNL) conducted this study for the Efficient Separations and Processing Crosscutting Program (ESP) under the task ''Develop and Test Sorbents.'' The purpose of the study was to assess and compare the chemical and radiolytic stability of several cesium-selective ion exchange materials in simulated alkaline Hanford tank waste matrices. Pretreatment of nuclear process wastes to remove of cesium and other radionuclides by ion exchange was proposed previously as one method of minimizing the amount of high-level radioactive waste at Hanford. In this study, PNL evaluated three cesium-selective materials SuperLig reg-sign 644, resorcinol-formaldehyde (R-F), and CS-100 for chemical and radiation stability in 1 M NaOH and a simulated neutralized current acid waste (NCAW). The objective of the study is to investigate the stability of the newly produced SuperLig reg-sign 644 under a variety of conditions in an attempt to simulate and predict the degradation process. The following specific conclusions and recommendations resulted from the study

  2. Conceptual study of in-tank cesium removal using an inorganic ion exchange material

    International Nuclear Information System (INIS)

    Presently, the Hanford Site contains approximately 230,000 m3 of mixed waste stored in 177 underground tanks. Approximately 55,000 m3 of this waste is sludge, 90,000 m3 is salt cake, and 80,000 m3 is supernate. Although the pretreatment and final disposal requirements for the waste have not been entirely defined, it is likely that some supernatant pretreatment will be required to remove 137Cs and possibly 90Sr and the transuranic components. The objective of this study was to estimate the number of HLW glass canisters resulting from the use of inorganic ion exchanger materials as in-tank pretreatment technology. The variables in the study were: number of contacts between waste and ion exchange material; ion exchange material; and decontamination requirement. This conceptual study investigates a generic in-tank Cs removal flowsheet using crystalline silico-titanates and IE-96 zeolites, and the impact of each ion exchanger on the number of glass canisters produced. In determining glass formulation, data based on current reference technology was used. Sample calculations from the worksheets and summaries of final calculated results are included at the end of this report

  3. Application of a composite sorbent based om natural and synthetic zeolites for cesium ion elimination from water solutions

    International Nuclear Information System (INIS)

    The study has been carried out to determine the effect of variations in the content of natural and synthetic zeolites, being the components of the composite sorbent, on the cesium sorption from the water solution

  4. Recovery of cesium ion from the aqueous solution by the electric occlusion using a porous aluminum electrode

    International Nuclear Information System (INIS)

    Using stable isotopic cesium with the concentration that simulated the pollution level around the Fukushima Daiichi Nuclear Power Station, the authors examined the occlusion capacity of a porous aluminum electrode based on a beaker-level experiment. A tested aluminum sample was made of metallic aluminum particles having an average particle diameter of 0.2 mm and a porosity of 50%. A cesium standard solution had 4 ppm of cesium chloride concentration, equivalent to 12.86 GBq/L when converted to radioactive cesium. A platinum anode and a porous aluminum cathode were used in the experiment. With occlusion time and applied voltage increased, cesium concentration decreased, reaching the concentration of trace with the applied voltage of 100 V for 90 min for occlusion, and nearly 0 ppm after 120 min. The occlusion capacity of the porous aluminum electrode was unabated even after 20 times of repetitions, exhibiting a high durability. The elution amount of the occluded cesium was 2.1% through washing, and 0.16% after reverse voltage added, which proved the effectiveness of the porous aluminum electrode. A similar effect was confirmed even in strontium. (A.O.)

  5. Analysis of radioactive cesium

    International Nuclear Information System (INIS)

    The procedure of analysis of cesium-137 in environmental samples is described. The standard measurement of cesium-137 is made by using a standard solution and a low background G-M counter system. Precipitation and dust are collected on a stainless steel pan. The collected samples are treated by evaporation and extraction or ion exchange and adsorption method. The sample is then quantitatively analyzed. The measurement of cesium-137 is made according to the standard of measurement. Samples collected from inland water and sea water are also treated by evaporation or ion exchange method. The measurements of cesium-137 are also made. This manual describes how to collect soil samples. The collected soil is dried and treated to make samples for activity measurement. Activity measurement is made according to the standard of measurement, then the data are analyzed. Samples are also collected from sediment of sea bottom or river bottom, agricultural products, milk, marine organisms, and daily foods. This manual describes on the methods to collect samples and the treatment to make samples for measurement. (Kato, T.)

  6. Cesium ion bombardment of metal surfaces: Final report for period January 1984 to May 1986

    International Nuclear Information System (INIS)

    The steady state Cs coverage due to Cs+ bombardment of polycrystalline Mo and W has been studied for the incident energy range below 500 eV. When a sample is exposed to a Cs+ ion beam, the work function decreases until steady state is reached with a total dose of less than ≅1*1016 ions/cm2, for both W and Mo. A steady state minimum work function surface is produced at an incident energy of ≅100 eV for Mo and at an incident energy of ≅45 eV for W. At a given bombarding energy the Cs coverage of W is uniformly less than that of Mo. H coadsorption does not have a large effect on the steady state work function. A theory describing the steady state coverage has been developed and is used to make predictions for other materials. 94 refs., 37 figs

  7. Electrochemical cesium sorption under coexisting other ions using nanoparticle film of copper hexacyanoferrate

    International Nuclear Information System (INIS)

    Copper hexacyanoferrate (CuHCF) is known as a good adsorbent for Cs. We developed water-dispersible CuHCF ink by nanoparticulation and surface treatment, and fabricated the thin film of CuHCF on metal electrodes. Cs adsorption/desorption can be controlled electrochemically using this thin film CuHCF electrode, repetitively. Cs sorption capability under coexisting other ions were examined for alkali metals, alkali earth metals, transition metals, etc, and determined to be few affected. (author)

  8. Literature Review of Spherical Resorcinol-Formaldehyde for Cesium Ion Exchange

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Garrett N.

    2014-09-30

    The current report summarizes work performed throughout the scientific community and DOE complex as reported in the open literature and DOE-sponsored reports to evaluate the Cs+ ion exchange (CIX) characteristics of SRF resin. King (2007) completed a similar literature review in support of material selection for the Small Column Ion Exchange (SCIX) project. Josephson et al. (2010) and Sams et al. (2009) provided a similar brief review of SRF CIX for the near-tank Cs+ removal (NTCR) project. Thorson (2008a) documented the basis for recommending SRF over SuperLigTM 644 as the primary CIX resin in the WTP. The current review expands on previous work, summarizes additional work completed to date, and provides a broad view of the literature without focusing on a specific column system. Although the focus of the current review is the SRF resin, many cited references include multiple materials such as the non-spherical GGRF and SuperLigTM 644 organic resins and crystalline silicotitanate (CST) IONSIVTM IE-911, a non-elutable inorganic material. This report summarizes relevant information provided in the literature.

  9. Immobilization of inorganic ion-exchanger into bio-polymer foams: application to cesium sorption

    International Nuclear Information System (INIS)

    Nickel-potassium ferrocyanide (along with other ferrocyanide sub-products, as shown by mineralization, SEM-EDX analyses) has been immobilized in highly porous discs of chitin for the sorption of Cs(I) from near neutral solutions. The immobilization process allows synthesizing stable materials that can bind up to 80 mg Cs g-1 (i.e., 240 mg Cs g-1 ion-exchanger). The pseudo-second order rate equation fits well kinetic profiles: the rate coefficient increases with the flow rate of recirculation (to force the access to potentially non-interconnected pores), as an evidence of the control of uptake kinetics by diffusion properties. Preliminary tests performed on 137Cs spiked solutions confirm the efficiency of the material for the treatment of effluents bearing radionuclides. (authors)

  10. Selective Removal Of Strontium And Cesium From Simulated Waste Solution With Titanate Ion Exchangers In A Filter Cartridge Configuration

    International Nuclear Information System (INIS)

    This report describes experimental results for the selective removal of strontium and cesium from simulated waste solutions using monosodium titanate (MST) and crystalline silicotitanate (CST)-laden filter cartridges. Four types of ion exchange cartridge media (CST and MST designed by both 3M and POROX(regsign)) were evaluated. In these proof-of-principle tests effective uptake of both Sr-85 and Cs-137 was observed. However, the experiments were not performed long enough to determine the saturation levels or breakthrough curve for each filter cartridge. POREX(regsign) MST cartridges, which by design were based on co-sintering of the active titanates with polyethylene particles, seem to perform as well as the 3M-designed MST cartridges (impregnated filter membrane design) in the uptake of strontium. At low salt simulant conditions (0.29 M Na+), the instantaneous decontamination factor (DF) for Sr-85 with the 3M-design MST cartridge measured 26, representing the removal of 96% of the Sr-85. On the other hand, the Sr-85 instantaneous DF with the POREX(regsign) design MST cartridge measured 40 or 98% removal of the Sr-85. Strontium removal with the 3M-design MST and CST cartridges placed in series filter arrangement produced an instantaneous decontamination factor of 41 or 97.6% removal compared to an instantaneous decontamination factor of 368 or 99.7% removal of the strontium with the POREX(regsign) MST and CST cartridge design placed in series. At high salt simulant conditions (5.6 M Na+), strontium removal with 3M-designed MST cartridge only and with 3M-designed MST and CST cartridges operated in a series configuration were identical. The instantaneous decontamination factor and the strontium removal efficiency, under the above configuration, averaged 8.6 and 88%, respectively. There were no POREX(regsign) cartridge experiments using the higher ionic strength simulant solution. At low salt simulant conditions, the uptake of Cs-137 with POREX(regsign) CST cartridge

  11. SELECTIVE REMOVAL OF STRONTIUM AND CESIUM FROM SIMULATED WASTE SOLUTION WITH TITANATE ION EXCHANGERS IN A FILTER CARTRIDGE CONFIGURATION

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L.; Martin, K.; Hobbs, D.

    2011-05-26

    This report describes experimental results for the selective removal of strontium and cesium from simulated waste solutions using monosodium titanate (MST) and crystalline silicotitanate (CST)-laden filter cartridges. Four types of ion exchange cartridge media (CST and MST designed by both 3M and POROX{reg_sign}) were evaluated. In these proof-of-principle tests effective uptake of both Sr-85 and Cs-137 was observed. However, the experiments were not performed long enough to determine the saturation levels or breakthrough curve for each filter cartridge. POREX{reg_sign} MST cartridges, which by design were based on co-sintering of the active titanates with polyethylene particles, seem to perform as well as the 3M-designed MST cartridges (impregnated filter membrane design) in the uptake of strontium. At low salt simulant conditions (0.29 M Na{sup +}), the instantaneous decontamination factor (D{sub F}) for Sr-85 with the 3M-design MST cartridge measured 26, representing the removal of 96% of the Sr-85. On the other hand, the Sr-85 instantaneous D{sub F} with the POREX{reg_sign} design MST cartridge measured 40 or 98% removal of the Sr-85. Strontium removal with the 3M-design MST and CST cartridges placed in series filter arrangement produced an instantaneous decontamination factor of 41 or 97.6% removal compared to an instantaneous decontamination factor of 368 or 99.7% removal of the strontium with the POREX{reg_sign} MST and CST cartridge design placed in series. At high salt simulant conditions (5.6 M Na{sup +}), strontium removal with 3M-designed MST cartridge only and with 3M-designed MST and CST cartridges operated in a series configuration were identical. The instantaneous decontamination factor and the strontium removal efficiency, under the above configuration, averaged 8.6 and 88%, respectively. There were no POREX{reg_sign} cartridge experiments using the higher ionic strength simulant solution. At low salt simulant conditions, the uptake of Cs-137 with

  12. Novel matching lens and spherical ionizer for a cesium sputter ion source

    International Nuclear Information System (INIS)

    The beam optics of a multi-sample sputter ion source, based on the NEC MCSNICS, has been modified to accommodate cathode voltages higher than 5 kV and dispenses with the nominal extractor. The cathode voltage in Cs sputter sources plays the role of the classical extractor accomplishing the acceleration of beam particles from eV to keV energy, minimizing space charge effects and interactions between the beam and residual gas. The higher the cathode voltage, the smaller are these contributions to the emittance growth. The higher cathode voltage also raises the Child's law limit on the Cs current resulting in substantially increased output. The incidental focusing role of the extractor is reallocated to a deceleration Einzel lens and the velocity change needed to match to the pre-acceleration tube goes to a new electrode at the tube entrance. All electrodes are large enough to ensure that the beam fills less than 30% of the aperture to minimize aberrations. The improvements are applicable to sputter sources generally. (author)

  13. Novel matching lens and spherical ionizer for a cesium sputter ion source

    Indian Academy of Sciences (India)

    D C Weisser; N R Lobanov; P A Hausladen; L K Fifield; H J Wallace; S G Tims; E G Apushkinsky

    2002-12-01

    The beam optics of a multi-sample sputter ion source, based on the NEC MCSNICS, has been modified to accommodate cathode voltages higher than 5 kV and dispenses with the nominal extractor. The cathode voltage in Cs sputter sources plays the role of the classical extractor accomplishing the acceleration of beam particles from eV to keV energy, minimizing space charge effects and interactions between the beam and residual gas. The higher the cathode voltage, the smaller are these contributions to the emittance growth. The higher cathode voltage also raises the Child’s law limit on the Cs current resulting in substantially increased output. The incidental focusing role of the extractor is reallocated to a deceleration Einzel lens and the velocity change needed to match to the pre-acceleration tube goes to a new electrode at the tube entrance. All electrodes are large enough to ensure that the beam fills less than 30% of the aperture to minimize aberrations. The improvements are applicable to sputter sources generally.

  14. Novel matching lens and spherical ionizer for a cesium sputter ion source

    Science.gov (United States)

    Weisser, D. C.; Lobanov, N. R.; Hausladen, P. A.; Fifield, L. K.; Wallace, H. J.; Tims, S. G.; Apushkinsky, E. G.

    2002-12-01

    The beam optics of a multi-sample sputter ion source, based on the NEC MCSNICS, has been modified to accommodate cathode voltages higher than 5 kV and dispenses with the nominal extractor. The cathode voltage in Cs sputter sources plays the role of the classical extractor accomplishing the acceleration of beam particles from eV to keV energy, minimizing space charge effects and interactions between the beam and residual gas. The higher the cathode voltage, the smaller are these contributions to the emittance growth. The higher cathode voltage also raises the Child's law limit on the Cs current resulting in substantially increased output. The incidental focusing role of the extractor is reallocated to a deceleration Einzel lens and the velocity change needed to match to the pre-acceleration tube goes to a new electrode at the tube entrance. All electrodes are large enough to ensure that the beam fills less than 30% of the aperture to minimize aberrations. The improvements are applicable to sputter sources generally.

  15. Ion selective electrode for cesium based on 5-(4'-nitrophenylazo)25,27-bis(2-propyloxy)26,28-dihydroxycalix[4]arene

    Energy Technology Data Exchange (ETDEWEB)

    Ramanjaneyulu, P.S. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085 (India); Singh, Parminder [Department of Chemistry, Indian Institute of Technology, New Delhi 110016 (India); Sayi, Y.S. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085 (India); Chawla, H.M. [Department of Chemistry, Indian Institute of Technology, New Delhi 110016 (India); Ramakumar, K.L., E-mail: klram@barc.gov.in [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai, Maharashtra 400085 (India)

    2010-03-15

    A polyvinylchloride (PVC) based liquid membrane ion selective electrode (ISE) for cesium was fabricated with 5-(4'-nitrophenylazo)25,27-bis(2-propyloxy)26,28-dihydroxycalix[4]arene as ionophore. Different membrane constituents were investigated to realise optimum performance of the ISE developed. Of the four plasticizers and two ion additives studied, the best response was observed with membrane having 2-nitro phenyl octyl ether (oNPOE) as plasticizer and potassium tetrakis (perchloro phenyl) borate (KTpClPB) as ion additive. Linear response over concentration range of 10{sup -5}-10{sup -1} M CsCl was obtained. The Nernstian slope of the response was 56 mV per decade for Cs with a response time less than 20 s. Matched potential method has been applied to find out the selectivity for Cs over several ions like Rb{sup +}, K{sup +}, Na{sup +}, NH{sub 4}{sup +}, Sr{sup 2+}, Ba{sup 2+}, Ca{sup 2+}, Mg{sup 2+}, Cu{sup 2+}, Pb{sup 2+}, Zn{sup 2+}, Ni{sup 2+} and Ce{sup 3+}. The response of ISE for Cs{sup +} was fairly constant over the pH range of 3-11. The lifetime of the electrode is 9 months which is the longest life for any membrane-based Cs-ISE so far developed. The concentration of cesium in two simulated high level active waste streams was determined and results agreed well with those obtained independently employing atomic absorption spectrometry.

  16. Anion Partitioning and Ion-Pairing Behavior of Anions in the Extraction of Cesium Salts by 4,5'-bix(tert-octylbenzo)dibenzo-24-crown-8 in 1,2-Dichloroethane

    International Nuclear Information System (INIS)

    A systematic study of anion partitioning and ion-pairing was performed for an extraction of individual cesium salts into 1,2-dichloroethane (1,2-DCE) using 4,5(doubleprime)-bis(tert-octylbenzo)dibenzo-24-crown-8 as the cesium receptor. Equilibrium constants corresponding to the extraction of ion pairs and dissociated ions, formation of the 1:1 cesium/crown complex (confirmed by electrospray mass spectrometry), and dissociation of the ion pairs in water-saturated 1,2-DCE at 25 C were obtained from equilibrium modeling using the SXLSQI program. The standard Gibbs energy of partitioning between water and water-saturated 1,2-DCE was determined for picrate, permanganate, trifluoromethanesulfonate, methanesulfonate, trifluoroacetate, and acetate anions. The dissociation of the organic-phase complex ion pair [Cs(4,4(doubleprime)-bis(tert-octylbenzo)dibenzo-24-crown-8)]+NO3 observed in the extraction experiments was shown to be consistent with the dissociation constant determined independently by conductance measurements. As attributed to the large effective radius of the complex cation, the evident anion discrimination due to ion-pairing in the 1,2-DCE phase, was relatively small, by comparison only a tenth of the discrimination exhibited by the anion partitioning. Only chloride and picrate exhibit evidence for significantly greater-than-expected ion-pairing tendency. These results provide insight into the inclusion properties of the clefts formed by opposing arene rings of the crown ether upon encapsulation of the Cs+ ion, whose weak anion recognition likely reflects the preferential inclusion of 1,2-DCE molecules in the clefts. Observed anion extraction selectivity in this system, which may be ascribed predominantly to solvent-induced Hofmeister bias selectivity toward large charge-diffuse anions, was nearly the same whether cesium salts were extracted as dissociated ions or ion pairs

  17. A mass spectrometric system for analyzing thermal desorption spectra of ion-implanted argon and cesium in tungsten. Ph.D. Thesis

    Science.gov (United States)

    Wood, G. M., Jr.

    1974-01-01

    A mass spectrometric system for determining the characteristics of materials used in instrumental development and aerospace applications was developed. The desorption spectra of cesium that was ion-implanted into polycrystalline tungsten and the effects on the spectra of bombardment of the tungsten by low energy (70 eV) electrons were investigated. Work function changes were measured by the retarding potential diode method. Flash desorption characteristics were observed and gas-reaction mechanisms of the surface of heated metal filaments were studied. Desorption spectra were measured by linearly increasing the sample temperature at a selected rate, the temperature cycling being generated from a ramp-driven dc power supply, with the mass spectrometer tuned to a mass number of interest. Results of the study indicate an anomolous desorption mechanism following an electron bombardment of the sample surface. The enhanced spectra are a function of the post-bombardment time and energy and are suggestive of an increased concentration of cesium atoms, up to 10 or more angstroms below the surface.

  18. Studies on cesium uptake by phenolic resins

    International Nuclear Information System (INIS)

    The selective removal of cesium by phenolic ion-exchange resins from highly salted alkaline radioactive solutions was studied. The resins were synthesized by alkaline polycondensation of phenol, resorcinol, catechol, and resorcinol-catechol mixture with formaldehyde and characterized for their moisture regain, ion-exchange (H+ → Na+) capacity, and distribution coefficient (KD) for cesium. The effects of open and sealed curing of the polymers on their properties were studied. The effect of Na+, NaOH, and Cs+ concentration on the uptake of cesium by resorcinol-formaldehyde resin was investigated, in particular. The chemical, thermal, and radiation stabilities of the polymers were also studied

  19. Cesium-137

    International Nuclear Information System (INIS)

    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 Cesium-137

  20. SELECTIVE REMOVAL OF STRONTIUM AND CESIUM FROM SIMULATED WASTE SOLUTION WITH TITANATE ION-EXCHANGERS IN A FILTER CARTRIDGE CONFIGURATIONS-12092

    Energy Technology Data Exchange (ETDEWEB)

    Oji, L.; Martin, K.; Hobbs, D.

    2011-11-10

    Experimental results for the selective removal of strontium and cesium from simulated waste solutions with monosodium titanate (MST) and crystalline silicotitanate (CST) laden filter cartridges are presented. In these proof-of-principle tests, effective uptake of both Sr-85 and Cs-137 were observed using ion-exchangers in this filter cartridge configuration. At low salt simulant conditions, the instantaneous decontamination factor (D{sub F}) for Sr-85 with MST impregnated filter membrane cartridges measured 26, representing 96% Sr-85 removal efficiency. On the other hand, the Sr-85 instantaneous D{sub F} with co-sintered active MST cartridges measured 40 or 98% Sr-85 removal efficiency. Strontium-85 removal with the MST impregnated membrane cartridges and CST impregnated membrane cartridges, placed in series arrangement, produced an instantaneous decontamination factor of 41 compared to an instantaneous decontamination factor of 368 for strontium-85 with co-sintered active MST cartridges and co-sintered active CST cartridges placed in series. Overall, polyethylene co-sintered active titanates cartridges performed as well as titanate impregnated filter membrane cartridges in the uptake of strontium. At low ionic strength conditions, there was a significant uptake of Cs-137 with co-sintered CST cartridges. Tests results with CST impregnated membrane cartridges for Cs-137 decontamination are currently being re-evaluated. Based on these preliminary findings we conclude that incorporating MST and CST sorbents into membranes represent a promising method for the semi-continuous removal of radioisotopes of strontium and cesium from nuclear waste solutions.

  1. Comparison of organic and inorganic ion exchangers for removal of cesium and strontium from simulated and actual Hanford 241-AW-101 DSSF tank waste

    International Nuclear Information System (INIS)

    A number of organic and inorganic exchangers are being developed and evaluated for cesium removal from Hanford tank wastes. The exchangers of interest that are investigated in this work include powdered (IONSIV reg-sign IE-910; referred to as IE-910) and engineered (IONSIV reg-sign IE-911; referred to as IE-911) forms of the crystalline silico-titanate (CST) inorganic sorbent developed by Sandia National Laboratories (SNL)/Texas A and M and prepared by UOP; a phenol-formaldehyde (CS-100) resin developed by Rohm and Haas; a resorcinol-formaldehyde (R-F) polymer developed at the Westinghouse Savannah River Company (WSRC) and produced by Boulder Scientific; an inorganic zeolite exchanger produced by UOP (IONSIV reg-sign TIE-96; referred to as TIE-96); an inorganic sodium titanate produced by Allied Signal/Texas A and M (NaTi); and a macrocyclic organic resin developed and produced by IBC Advanced Technologies (SuperLig reg-sign 644; referred to as SL-644). Several of these materials are still under development and may not be in the optimal form. The work described in this report involves the direct comparison of the ion exchange materials for the pretreatment of actual and simulated Hanford tank waste. Data on the performance of all of the exchangers with simulated and actual double shell slurry feed (DSSF) is included. The DSSF waste is a mixture of the supernate from tanks 101-AW (70%), 106-AP (20%) and 102-AP (10%). The comparative parameters include radionuclide removal efficiency under a variety of conditions and material properties (e.g., bed density and percent removable water). Cesium and strontium distribution (Kd), lambda (λ = Kd x ρb), and decontamination factors (DF) are compared as a function of exchanger contact duration, solution composition (Na and Cs concentration), exchanger/waste phase ratio, and multiple sequential contacts

  2. Application of Liquid Solid Semi-moving Bed to Fractionation of Cesium Ion in Wastewater%液固半移动床分离废水中铯离子的应用

    Institute of Scientific and Technical Information of China (English)

    徐聪; 冯孝贯; 景山

    2007-01-01

    A liquid solid semi-moving bed with non-mechanical particle transport system is proposed and used for fractionation of cesium ion in wastewater. The particle transport system, which consists of a suction chamber, a mixing chamber, a nozzle and a riser tube, is designed to be controlled completely by hydraulic force. Experiments show that continuous feeding and discharging of resin can be realized by the transport system. The removal of cesium ion from wastewater is realized. The concentration of cesium ion in effluent liquid remains below 0.1g·L-1 (the initial concentration is 5.3g·L-1) during the 73 hours'experiment. The average exchange capacity of resin discharged from the bed is 0.57mmol·(g dry resin) -1, which is close to the saturated capacity of 0.65mmol·g-1. And it is also proved that the non-homogeneity of particle vertical velocity along the radial direction can seriously influence the ion-exchange process.

  3. Response of silicon multistrip detectors and a cesium iodide scintillator to a calcium ion beam of 0.5 GeV/u

    International Nuclear Information System (INIS)

    We have constructed and operated charge preamplifiers for silicon strip detectors with a dynamic range extending from fractions of minimum ionising particle (MIP) up to 16 124 MIPs. These silicon detectors combined with time-of-flight counters and cesium iodide scintillator form a segment of the VENUS detector that has been exposed to a calcium beam of 0.5 GeV/u at the GSI accelerator. The aim of the instrument is the identification of all nuclides of the periodic table of the elements. Measurements of electronic noise, cross-talk among channels and energy deposit resolutions in various experimental conditions for silicon detectors are given. The measured light output of the CsI(Tl) crystal induced by calcium is compared with that extrapolated from lower-energy data of various nuclide species determined in other experiments. The charge resolution for calcium ions, determined by the dE/dx detectors and TOF counters of time resolution of 55±7 ps, amounts to 0.42 charge units (rms). Improvements in ion discrimination with respect to the present detector configuration are considered. (orig.)

  4. Response of silicon multistrip detectors and a cesium iodide scintillator to a calcium ion beam of 0.5 GeV/u

    Energy Technology Data Exchange (ETDEWEB)

    Codino, A.; Miozza, M.; Brunetti, M.T.; Checcucci, B.; Federico, C.; Grimani, C.; Lanfranchi, M.; Macchiaiolo, T.; Menichelli, M.; Maffei, P.; Vocca, H. [Istituto Nazionale di Fisica Nucleare, Perugia (Italy); Plouin, F. [Laboratoire National de Saturne, 91191 Gif-sur-Yvette Cedex (France)

    1997-10-21

    We have constructed and operated charge preamplifiers for silicon strip detectors with a dynamic range extending from fractions of minimum ionising particle (MIP) up to 16 124 MIPs. These silicon detectors combined with time-of-flight counters and cesium iodide scintillator form a segment of the VENUS detector that has been exposed to a calcium beam of 0.5 GeV/u at the GSI accelerator. The aim of the instrument is the identification of all nuclides of the periodic table of the elements. Measurements of electronic noise, cross-talk among channels and energy deposit resolutions in various experimental conditions for silicon detectors are given. The measured light output of the CsI(Tl) crystal induced by calcium is compared with that extrapolated from lower-energy data of various nuclide species determined in other experiments. The charge resolution for calcium ions, determined by the dE/dx detectors and TOF counters of time resolution of 55{+-}7 ps, amounts to 0.42 charge units (rms). Improvements in ion discrimination with respect to the present detector configuration are considered. (orig.). 12 refs.

  5. Removal efficiency of radioactive cesium and iodine ions by a flow-type apparatus designed for electrochemically reduced water production.

    Directory of Open Access Journals (Sweden)

    Takeki Hamasaki

    Full Text Available The Fukushima Daiichi Nuclear Power Plant accident on March 11, 2011 attracted people's attention, with anxiety over possible radiation hazards. Immediate and long-term concerns are around protection from external and internal exposure by the liberated radionuclides. In particular, residents living in the affected regions are most concerned about ingesting contaminated foodstuffs, including drinking water. Efficient removal of radionuclides from rainwater and drinking water has been reported using several pot-type filtration devices. A currently used flow-type test apparatus is expected to simultaneously provide radionuclide elimination prior to ingestion and protection from internal exposure by accidental ingestion of radionuclides through the use of a micro-carbon carboxymethyl cartridge unit and an electrochemically reduced water production unit, respectively. However, the removability of radionuclides from contaminated tap water has not been tested to date. Thus, the current research was undertaken to assess the capability of the apparatus to remove radionuclides from artificially contaminated tap water. The results presented here demonstrate that the apparatus can reduce radioactivity levels to below the detection limit in applied tap water containing either 300 Bq/kg of 137Cs or 150 Bq/kg of 125I. The apparatus had a removal efficiency of over 90% for all concentration ranges of radio-cesium and -iodine tested. The results showing efficient radionuclide removability, together with previous studies on molecular hydrogen and platinum nanoparticles as reactive oxygen species scavengers, strongly suggest that the test apparatus has the potential to offer maximum safety against radionuclide-contaminated foodstuffs, including drinking water.

  6. Two-Step Method for Preparation of NaA-X Zeolite Blend from Fly Ash for Removal of Cesium ions

    International Nuclear Information System (INIS)

    Pure zeolites can be synthesized from silica extracts obtained from fly ash by alkaline leaching. The extraction potential of industrial by-product fly ash was investigated under repeated fusion process conditions. The amount of extracted silica was 131.43 g/kg ash while the amount extracted alumina was limited to 41.72 g/kg ash. The results of zeolite synthesis from the Si-bearing extracts demonstrated that pure zeolites with high cation exchange capacity (4.624 m eq/g) can be produced. The sorption potential of synthesized A-X zeolite blend for the removal of cesium ions has been investigated. The influences of ph, contact time and temperature have been reported. Thermodynamic parameters such as changes in Gibbs free energy (δG degree), enthalpy (δH degree) and entropy (δS degree) were calculated. A comparison of kinetic models applied to the sorption data was evaluated for pseudo-first order, pseudo-second order and homogeneous particle diffusion models. The results showed that both the pseudo-second order and the homogeneous particle diffusion models were found to best correlate the experimental rate data

  7. Biosorption behavior and mechanism of cesium-137 on Rhodosporidium fluviale strain UA2 isolated from cesium solution

    International Nuclear Information System (INIS)

    In order to identify a more efficient biosorbent for 137Cs, we have investigated the biosorption behavior and mechanism of 137Cs on Rhodosporidium fluviale (R. fluviale) strain UA2, one of the dominant species of a fungal group isolated from a stable cesium solution. We observed that the biosorption of 137Cs on R. fluviale strain UA2 was a fast and pH-dependent process in the solution composed of R. fluviale strain UA2 (5 g/L) and cesium (1 mg/L). While a Langmuir isotherm equation indicated that the biosorption of 137Cs was a monolayer adsorption, the biosorption behavior implied that R. fluviale strain UA2 adsorbed cesium ions by electrostatic attraction. The TEM analysis revealed that cesium ions were absorbed into the cytoplasm of R. fluviale strain UA2 across the cell membrane, not merely fixed on the cell surface, which implied that a mechanism of metal uptake contributed largely to the cesium biosorption process. Moreover, PIXE and EPBS analyses showed that ion-exchange was another biosorption mechanism for the cell biosorption of 137Cs, in which the decreased potassium ions were replaced by cesium ions. All the above results implied that the biosorption of 137Cs on R. fluviale strain UA2 involved a two-step process. The first step is passive biosorption that cesium ions are adsorbed to cells surface by electrostatic attraction; after that, the second step is active biosorption that cesium ions penetrate the cell membrane and accumulate in the cytoplasm. - Highlights: • Microorganisms isolated from a cesium solution are considered as a biosorbent to remove cesium ions. • The biosorption equilibrium is fitted well to a Langmuir model with a correlation coefficient of 0.9997. • First attempt to explore biosorption mechanisms using PIXE and EPBS. • Living and dead microorganisms have different biosorption mechanisms. • The biosorption of 137Cs involved a two-step process: passive and active

  8. Cesium pre-implantation of embedded biological sections

    International Nuclear Information System (INIS)

    An ion implantation system which allows the implantation of a large surface of a specimen has been used to obtain an homogeneous enrichment with cesium of embedded biological tissues sections. In such a specimen, containing already oxygen at a high concentration, the addition of cesium allows both positive and negative secondary ions to be studied with the highest sensitivity, using the same primary ion source.

  9. An experimental study of charge exchange process in the energy range 1-30 keV during the passage of alkali metal ions and atoms through cesium and potassium vapour

    International Nuclear Information System (INIS)

    An experimental study is presented of the charge exchange processes in the energy range of about 1-30 keV during the passage of positive alkali ions and alkali atoms through potassium and cesium vapour. The experimental set-up designed for this experiment includes a thermionic source for positive alkali ions with an acceleration stage, a first charge exchange cell to produce fast alkali atoms, a second charge exchange cell with a surface ionisation detector to determine the alkali metal vapor target thickness and a detection system with electrostatic bending of the charged secondary species. The maximum negative ion yield has been determined for the collision systems Li+ + K, Na+ + K, K+ + K, and Rb+ + K, and for another eleven systems the charge transfer cross-sections have been measured too. (orig./GG)

  10. Cesium chemistry in irradiated fuel; cesium uranates

    International Nuclear Information System (INIS)

    The physico-chemical behaviour of fission products in nuclear fuel during and after irradiation has been studied extensively during the past decades. In spite of the large amount of chemical, crystallographic and thermodynamic data available, the knowledge on the very complicated UO2-fission product system is still far from complete. The paper discusses the multi variant character of uranium in cesium uranates, which has been assessed by a systematic X-ray Photoelectron Spectroscopy (XPS) study of a series of cesium uranates

  11. Crystalline silicotitanates for cesium/strontium removal

    Energy Technology Data Exchange (ETDEWEB)

    Brown, N.; Miller, J.; Sherman, J.

    1996-10-01

    A new class of inorganic ion exchangers called crystalline silicotitanates (CST) has been developed that exhibits very high selectivity for cesium and strontium in the highly alkaline radioactive wastes at the Hanford Site and other DOE sites. Tests have also shown that CSTs have high selectivity for cesium in acidic and neutral solutions. The ESP is supporting an effort at Sandia National Laboratories and Texas A & M University to further develop and characterize the important chemical and physical properties that will determine the applicability of CST to radioactive waste treatment at Hanford and other DOE facilities.

  12. Sorption of cesium and strontium by arid region desert soil

    International Nuclear Information System (INIS)

    Adsorption and ion exchange in soil systems are the principal mechanisms that retard the migration of nuclear waste to the biosphere. Cesium and strontium are two elements with radioactive isotopes (Cs137 and Sr90) that are commonly disposed of as nuclear waste. The sorption and ion exchange properties of nonradioactive cesium and strontium were studied in this investigation. The soil used in this study was collected at an experimental infiltration site on Frenchman Flat, a closed drainage basin on the Nevada Test Site. This soil is mostly nonsaline-alkali sandy loam and loamy sand with a cation exchange capacity ranging from 13 to 30 me/100g. The clay fraction of the soil contains illite, montmorillonite, and clinoptilolite. Ion exchange studies have shown that this soil sorbs cesium preferentially relative to strontium, and that charge for charge, the exchange-phase cations released from exchange sites exceed the cesium and strontium sorbed by the soil. 38 references, 22 figures

  13. Adsorption of cesium on cement mortar from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Volchek, Konstantin, E-mail: konstantin.volchek@ec.gc.ca [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, Canada K1A 0H3 (Canada); Miah, Muhammed Yusuf [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, Canada K1A 0H3 (Canada); Department of Applied Chemistry and Chemical Technology, Noakhali Science and Technology University (Bangladesh); Kuang, Wenxing; DeMaleki, Zack [Emergencies Science and Technology Section, Environment Canada, 335 River Road, Ottawa, Ontario, Canada K1A 0H3 (Canada); Tezel, F. Handan [Department of Chemical and Biological Engineering, University of Ottawa, 161 Louis-Pasteur, Ottawa, Ontario, Canada K1N 6N5 (Canada)

    2011-10-30

    Highlights: {yields} The adsorption of cesium on cement mortar was investigated in a range of temperatures and cesium concentrations. {yields} The pseudo-second order kinetic model produced a good fit with the experimental kinetic data. {yields} Equilibrium test results correlated well with the Freundlich isotherm adsorption model. {yields} The interaction between cesium ions and cement mortar was dominated by chemical adsorption. - Abstract: The adsorption of cesium on cement mortar from aqueous solutions was studied in series of bench-scale tests. The effects of cesium concentration, temperature and contact time on process kinetics and equilibrium were evaluated. Experiments were carried out in a range of initial cesium concentrations from 0.0103 to 10.88 mg L{sup -1} and temperatures from 278 to 313 K using coupons of cement mortar immersed in the solutions. Non-radioactive cesium chloride was used as a surrogate of the radioactive {sup 137}Cs. Solution samples were taken after set periods of time and analyzed by inductively coupled plasma mass spectroscopy. Depending on the initial cesium concentration, its equilibrium concentration in solution ranged from 0.0069 to 8.837 mg L{sup -1} while the respective surface concentration on coupons varied from 0.0395 to 22.34 {mu}g cm{sup -2}. Equilibrium test results correlated well with the Freundlich isotherm model for the entire test duration. Test results revealed that an increase in temperature resulted in an increase in adsorption rate and a decrease in equilibrium cesium surface concentration. Among several kinetic models considered, the pseudo-second order reaction model was found to be the best to describe the kinetic test results in the studied range of concentrations. The adsorption activation energy determined from Arrhenius equation was found to be approximately 55.9 kJ mol{sup -1} suggesting that chemisorption was the prevalent mechanism of interaction between cesium ions and cement mortar.

  14. Decorporation of cesium-137

    International Nuclear Information System (INIS)

    Cesium radio-isotopes, especially cesium-137 (137Cs) are among the radionuclides of main importance produced by a fission reaction in reactor or a nuclear weapon explosion. In the environment, 137Cs is a major contaminant which can cause severe β, γirradiations and contaminations. 137Cs is distributed widely and relatively uniformly throughout the body with the highest concentration in skeletal muscles. A treatment becomes difficult afterwards. The purposes of this report are Firstly to compare the Prussian blue verses cobalt and potassium ferrocyanide (D.I. blue) efficiency for the 137Cs decorporation and secondly to assess a chronological treatment with D.I. blue. (author)

  15. Poly(vinyl alcohol) and alginate cross-linked matrix with immobilized Prussian blue and ion exchange resin for cesium removal from waters.

    Science.gov (United States)

    Lai, Yu-Chen; Chang, Yin-Ru; Chen, Man-Li; Lo, Yu-Kuo; Lai, Juin-Yih; Lee, Duu-Jong

    2016-08-01

    Cesium (Cs) removal from contaminated water bodies is an emerging issue after the disaster at the Fukushima Daiichi Nuclear Power Plant. The Prussian blue (PB) is an effective Cs adsorbent but will release hexacyanoferrate fragments from the adsorbent matrix during adsorption. Alginate is an affordable biopolymer for PB particles immobilization. This study synthesized poly(vinyl alcohol) (PVA) and alginate cross-linked matrix for immobilization of PB nano-sized particles and a surface-modified styrene-ethyl styrene divinyl benzene resin and tested their swelling stability and Cs adsorption performance in fresh water and in seawater. The PVA-alginate granules have high structural stability in both fresh water and seawater, with the Cs adsorption capability higher for the former than the latter. The adopted resin effectively remove released PB fragments from the tested granules. The transport and reaction parameters for the granules and for the sand filter bed were estimated. PMID:27132227

  16. Sorption of cesium on Olkiluoto mica gneiss, granodiorite and granite

    International Nuclear Information System (INIS)

    Cesium was selected as a model to study the sorption in bedrock occurring by ion exchange mechanism. The aim of the study was to supplement the existing data on sorption occurring by ion exchange mechanism in bedrock of the candidate sites for spent fuel disposal at Olkiluoto. The sorption of cesium was studied on crushed mica gneiss, tonalite (granodiorite) and granite in artificial groundwaters. Fresh water was represented by Allard water, pH 8 and pH 7, and saline water by Ol-So water, pH 7 and pH 9. In addition, a Na-Ca-Cl brine water and its 1:10 dilution were used as simulants. Cesium concentrations were between 10-8 and 10-3 mol/l. The distribution coefficients of the sorption, Rd and Ra values were determined by batch method. Isotherms were partly non-linear with slopes 0.7 - 1.0 depending on rock and water. At the end of the sorption experiment, the water was analysed for cations exchanged for cesium. The sorption of cesium was also studied as a function of ionic strength. The ionic strength increased in the order Allard < 0l-Br 1:10 < 0l-So < 0l-Br. The sorption of cesium was lower at higher ionic strength and higher Cs concentration. The mineral composition of rocks was determined by thin section analysis, and the sorption distribution ratios on thin sections in the different waters were determined by batch technique. The minerals, that sorbed most cesium were determined by autoradiography. These were biotite, muscovite and chlorite. Cordierite in mica gneiss also sorbed cesium very effectively. (orig.)

  17. Sorption of cesium on Olkiluoto mica gneiss, granodiorite and granite

    Energy Technology Data Exchange (ETDEWEB)

    Huitti, T.; Hakanen, M. [Univ. of Helsinki (Finland). Lab. of Radiochemistry; Lindberg, A. [Geological Survey of Finland, Espoo (Finland)

    1998-09-01

    Cesium was selected as a model to study the sorption in bedrock occurring by ion exchange mechanism. The aim of the study was to supplement the existing data on sorption occurring by ion exchange mechanism in bedrock of the candidate sites for spent fuel disposal at Olkiluoto. The sorption of cesium was studied on crushed mica gneiss, tonalite (granodiorite) and granite in artificial groundwaters. Fresh water was represented by Allard water, pH 8 and pH 7, and saline water by Ol-So water, pH 7 and pH 9. In addition, a Na-Ca-Cl brine water and its 1:10 dilution were used as simulants. Cesium concentrations were between 10{sup -8} and 10{sup -3} mol/l. The distribution coefficients of the sorption, R{sub d} and R{sub a} values were determined by batch method. Isotherms were partly non-linear with slopes 0.7 - 1.0 depending on rock and water. At the end of the sorption experiment, the water was analysed for cations exchanged for cesium. The sorption of cesium was also studied as a function of ionic strength. The ionic strength increased in the order Allard < 0l-Br 1:10 < 0l-So < 0l-Br. The sorption of cesium was lower at higher ionic strength and higher Cs concentration. The mineral composition of rocks was determined by thin section analysis, and the sorption distribution ratios on thin sections in the different waters were determined by batch technique. The minerals, that sorbed most cesium were determined by autoradiography. These were biotite, muscovite and chlorite. Cordierite in mica gneiss also sorbed cesium very effectively. (orig.) 12 refs.

  18. Thermoemission and adsorption properties of diborides of transition metals of IV-V groups in cesium vapours

    International Nuclear Information System (INIS)

    Emission and adsorption properties of titanium, zirconium, hafnium, vanadium diborides were studied in vacuum and cesium vapours. Some regularities were established in changes of thermoemission properties in transition from one boride to another. Under pressures p0K interaction of these diborides with cesium plasma is of adsorption character. Evaluation of absorption properties for the diborides in cesium vapours showed for oprimal surface coating with cesium the adsorption energy for cesium ions is qsub(a)=(1.1/1.3) eV and work function is phi sub(min)=(1.25/1.45) eV

  19. Equilibrium and kinetic studies of the sorption of cesium by potassium nickel hexacyanoferrate complex

    International Nuclear Information System (INIS)

    Sorption of cesium from nitric acid medium by potassium nickel hexacyanoferrate, KNiFC, was investigated using the batch technique. The effect of hydrogen ion concentration on the distribution coefficient of cesium has been studied in the pH range 1-5.5. The effect of particle size, the temperature on the sorption equilibrium and rate of uptake of cesium were investigated. The temperature effect on both sorption equilibrium and rate of uptake was found to be limited. The kinetic study shows that the sorption is controlled by particle diffusion mechanism. The diffusivity of cesium ions into different particle sizes of KNiFC, the activation energy, and the entropy change of the sorption process were calculated. The effect of the presence of cobalt ions on the equilibrium and the rate of uptake of cesium is presented. (author)

  20. Preparation of Modified Kaolin Filler with Cesium and Its Application in Security Paper

    OpenAIRE

    Houssni El-Saied; Samya El-Sherbiny; Omnia Ali; Wafaa El-Saied; Said Rohyem

    2013-01-01

    In this study, cesium was added intentionally during paper manufacture for protecting the papers against forgery and counterfeiting by sorbing cesium ions (Cs+) on kaolin, used as special filler in papermaking. The sorption of cesium from aqueous solution by kaolin was studied as a function of pH, shaking time, cesium initial concentration, and mass of kaolin using batch technique. The results showed that a solution containing 10 mg/L Cs+ and 250 mg of kaolin at pH 6 can be used to modify the...

  1. Laboratory plant for the separation of cesium from waste solutions of the PUREX process

    International Nuclear Information System (INIS)

    A laboratory plant for the separation of cesium from a fission product waste solution of the fuel reprocessing is described. The plant consists of two stages. In the first stage cesium is adsorbed on ammonium molybdatophosphate (AMP). Then the adsorbent is dissolved. From the solution cesium is adsorbed on a cationic ion exchanger in the second stage. Then AMP can be reproduced from this solution. For the elution of cesium in the second stage a NH4NO3 solution (3 m) is used. Flow sheet, construction and the control device of the plant are described and the results of tests with a model solution are given. (author)

  2. Studies on the Separation of Cesium From Fission Products

    Institute of Scientific and Technical Information of China (English)

    QIANLi-juan; ZHANGSheng-dong; GUOJing-ru; CUIAn-zhi; YANGLei; WUWang-suo

    2003-01-01

    135Cs is a long-life fission product. When measuring its thermal cross section, we must separate radiochemical purity cesium from fission products. Except for decontaminating radio- nuclides, others which can be activated must be avoided to come into solution. So ion exchanger is used. Inorganic ion exchangers have received increased attention because of their high resistance to radiation and their very efficient separation of alkali metal ions.

  3. Cesium reservoir and interconnective components

    International Nuclear Information System (INIS)

    The program objective is to demonstrate the technology readiness of a TFE (thermionic fuel element) suitable for use as the basic element in a thermionic reactor with electric power output in the 0.5 to 5.0 MW range. A thermionic converter must be supplied with cesium vapor for two reasons. Cesium atoms adsorbed on the surface of the emitter cause a reduction of the emitter work function to permit high current densities without excessive heating of the emitter. The second purpose of the cesium vapor is to provide space-charge neutralization in the emitter-collector gap so that the high current densities may flow across the gap unattenuated. The function of the cesium reservoir is to provide a source of cesium atoms, and to provide a reserve in the event that cesium is lost from the plasma by any mechanism. This can be done with a liquid cesium metal reservoir in which case it is heated to the desired temperature with auxiliary heaters. In a TFE, however, it is desirable to have the reservoir passively heated by the nuclear fuel. In this case, the reservoir must operate at a temperature intermediate between the emitter and the collector, ruling out the use of liquid reservoirs. Integral reservoirs contained within the TFE will produce cesium vapor pressures in the desired range at typical electrode temperatures. The reservoir material that appears to be the best able to meet requirements is graphite. Cesium intercalates easily into graphite, and the cesium pressure is insensitive to loading for a given intercalation stage. The goals of the cesium reservoir test program were to verify the performance of Cs-graphite reservoirs in the temperature-pressure range of interest to TFE operation, and to test the operation of these reservoirs after exposure to a fast neutron fluence corresponding to seven year mission lifetime. In addition, other materials were evaluated for possible use in the integral reservoir

  4. Cesium-137 in biosphere

    International Nuclear Information System (INIS)

    The behaviour of cesium-137 in environment is reviewed. Problems on 137Cs migration in environment, on metabolism andbiological effects are considered. Data on nuclide accumulation in various plants, ways of their entering the man's organism are presented. It is marked that the rate of 137Cs metabolism in the man's organism depends considerably on age, sex, temperature of environment, conditions for activity, water and mineral metabolism and some other factors. It is shown that the annual effective equivalent dose per capita will increase to 2000 yr. up to 1 μSv, that constitutes 0.05% of the average value of irradiation by a natural source

  5. Mobility of cesium through the Callovo-Oxfordian claystones under partially saturated conditions

    International Nuclear Information System (INIS)

    The diffusion of cesium was studied in an unsaturated core of Callovo-Oxfordian claystone, which is a potential host rock for retrievable disposal of high-level radioactive wastes. In-diffusion laboratory experiments were performed on rock samples with water saturation degrees ranging from 81% to 100%. The analysis of both cesium concentration monitoring in the source reservoir and postmortem cesium rock concentration profile of the samples was carried out using a chemical-transport code where the sorption of cesium was described by a multi-site ion-exchange model. The results showed that cesium exhibited a clear trend related to the saturation degree of the sample. The more dehydrated the rock sample, the slower the decrease of cesium concentration, and the thinner the penetration depth of cesium was. The effective diffusion coefficient (De) for cesium decreased from 18.5 *10-11 m2 s-1 at full-saturation to 0.3 * 10-11 m2 s-1 for the more dehydrated sample. This decrease is almost 1 order of magnitude higher than that for tritiated water (HTO), although a similar behavior could have been expected, since cesium is known to diffuse in the same parts of the pore space as HTO in fully saturated claystones. (authors)

  6. Monitoring of radionuclides in the environment. Part. 4. Factors influencing depth profiles of radioactive cesium in soils

    International Nuclear Information System (INIS)

    In order to evaluate the vertical migration behavior of radioactive cesium, which contaminated by the Fukushima Dai-ichi NPP accident, the distribution of radioactive cesium in different type of soils, e.g., bare ground, grass land, conifer forest floor were measured on October 2011, 2012, 2013, in Abiko, Chiba, Japan. Even three years after the deposition, most of radioactive cesium were deposited in the depths of within 5 cm at anywhere in this area. Depth profiles of radioactive cesium in soil was significantly correlated with organic matter content in soils (r=0.82; p<0.0001), whereas the factors such as potassium ion and ammonium ion in soil, stable cesium content, and clay mineral content were not correlated clearly. This indicates that the vertical migration rate of radioactive cesium is very slow and it would be influenced by organic matter in soil, not just clay. (author)

  7. Plasma etching of cesium iodide

    International Nuclear Information System (INIS)

    Thick films of cesium iodide (CsI) are often used to convert x-ray images into visible light. Spreading of the visible light within CsI, however, reduces the resolution of the resulting image. Anisotropic etching of the CsI film into an array of micropixels can improve the image resolution by confining light within each pixel. The etching process uses a high-density inductively coupled plasma to pattern CsI samples held by a heated, rf-biased chuck. Fluorine-containing gases such as CF4 are found to enhance the etch rate by an order of magnitude compared to Ar+ sputtering alone. Without inert-gas ion bombardment, however, the CF4 etch becomes self-limited within a few microns of depth due to the blanket deposition of a passivation layer. Using CF4+Ar continuously removes this layer from the lateral surfaces, but the formation of a thick passivation layer on the unbombarded sidewalls of etched features is observed by scanning electron microscopy. At a substrate temperature of 220 deg. C, the minimum ion-bombardment energy for etching is Ei∼50 eV, and the rate depends on Ei1/2 above 65 eV. In dilute mixtures of CF4 and Ar, the etch rate is proportional to the gas-phase density of atomic fluorine. Above 50% CF4, however, the rate decreases, indicating the onset of net surface polymer deposition. These observations suggest that anisotropy is obtained through the ion-enhanced inhibitor etching mechanism. Etching exhibits an Arrhenius-type behavior in which the etch rate increases from ∼40 nm/min at 40 deg. C to 380 nm/min at 330 deg. C. The temperature dependence corresponds to an activation energy of 0.13±0.01 eV. This activation energy is consistent with the electronic sputtering mechanism for alkali halides

  8. Cesium leaching from {gamma}-irradiated CsA and CsX zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Enrique [Universidad Autonoma Metropolitana, Iztapalapa, A. P. 55-532, Av. San Rafael Atlixco No. 186 Col. Vicentina, 09340 Mexico, D.F. (Mexico)], E-mail: lima@xanum.uam.mx; Ibarra, Ilich A.; Lara, Victor [Universidad Autonoma Metropolitana, Iztapalapa, A. P. 55-532, Av. San Rafael Atlixco No. 186 Col. Vicentina, 09340 Mexico, D.F. (Mexico); Bosch, Pedro [Instituto de Investigaciones en Materiales, A. P. 70-360, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, 04510 Mexico, D.F. (Mexico); Bulbulian, Silvia [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Col. Escandon, Delegacion Miguel Hidalgo, 11801 Mexico, D.F. (Mexico)

    2008-12-30

    The present study discusses the effect of {gamma}-irradiation on Cs{sup +}-exchanged X and A zeolites. The incorporation of Cs{sup +} ions into A and X zeolites was performed using three different cesium salts (chloride, nitrate or acetate). Cs{sup +} ions immobilized into the vitrified zeolites by thermal treatment are located in different sites of the zeolite networks. It is found that {gamma}-irradiation favors cesium retention depending on the cesium precursor salt used in the cationic exchange step.

  9. Ionizing mechanisms in a cesium plasma irradiated with a ruby laser

    Science.gov (United States)

    Shimada, K.; Robinson, L. B.

    1975-01-01

    A cesium filled diode--laser plasmadynamic converter was built to investigate the feasibility of converting laser energy to electrical energy at large power levels. Experiments were performed with a pulsed ruby laser to determine the quantity of electrons and cesium ions generated per pulse of laser beam and to determine the output voltage. A current density as high as 200 amp/sq cm from a spot of approximately 1 sq mm area and an open circuit voltage as high as 1.5 volts were recorded. A qualitative theory was developed to explain these results. In the operation of the device, the laser beam evaporates some of the cesium and ionizes the cesium gas. A dense cesium plasma is formed to absorb further the laser energy. Results suggest that the simultaneous absorption of two ruby laser photons by the cesium atoms plays an important role in the initial ionization of cesium. Inverse bremsstrahlung absorption appears to be the dominant mechanism in subsequent processes. Recombinations of electrons and cesium ions appear to compete favorably with the simultaneous absorption of two photons.

  10. Characterization of quantum efficiency and robustness of cesium-based photocathodes

    Science.gov (United States)

    Montgomery, Eric J.

    High quantum efficiency, robust photocathodes produce picosecond-pulsed, high-current electron beams for photoinjection applications like free electron lasers. In photoinjectors, a pulsed drive laser incident on the photocathode causes photoemission of short, dense bunches of electrons, which are then accelerated into a relativistic, high quality beam. Future free electron lasers demand reliable photocathodes with long-lived quantum efficiency at suitable drive laser wavelengths to maintain high current density. But faced with contamination, heating, and ion back-bombardment, the highest efficiency photocathodes find their delicate cesium-based coatings inexorably lost. In answer, the work herein presents careful, focused studies on cesium-based photocathodes, particularly motivated by the cesium dispenser photocathode. This is a novel device comprised of an efficiently photoemissive, cesium-based coating deposited onto a porous sintered tungsten substrate, beneath which is a reservoir of elemental cesium. Under controlled heating cesium diffuses from the reservoir through the porous substrate and across the surface to replace cesium lost to harsh conditions---recently shown to significantly extend the lifetime of cesium-coated metal cathodes. This work first reports experiments on coated metals to validate and refine an advanced theory of photoemission already finding application in beam simulation codes. Second, it describes a new theory of photoemission from much higher quantum efficiency cesium-based semiconductors and verifies its predictions with independent experiment. Third, it investigates causes of cesium loss from both coated metal and semiconductor photocathodes and reports remarkable rejuvenation of full quantum efficiency for contaminated cesium-coated surfaces, affirming the dispenser prescription of cesium resupply. And fourth, it details continued advances in cesium dispenser design with much-improved operating characteristics: lower temperature

  11. Sorption of cesium in intact rock

    Energy Technology Data Exchange (ETDEWEB)

    Puukko, E. [Univ. of Helsinki, Dept. of Chemistry (Finland)

    2014-04-15

    The mass distribution coefficient K{sub d} is used in performance assessment (PA) to describe sorption of a radionuclide on rock. The R{sub d} is determined using crushed rock which causes uncertainty in converting the R{sub d} values to K{sub d} values for intact rock. This work describes a method to determine the equilibrium of sorption on intact rock. The rock types of the planned Olkiluoto waste disposal site were T-series mica gneiss (T-MGN), T-series tonalite granodiorite granite gneiss (T-TGG), P-series tonalite granodiorite granite gneiss (P-TGG) and pegmatitic granite (PGR). These rocks contain different amount of biotite which is the main sorbing mineral. The sorption of cesium on intact rock slices was studied by applying an electrical field to speed up migration of cesium into the rock. Cesium is in the solution as a noncomplex cation Cs{sup +} and it is sorbed by ion exchange. The tracer used in the experiments was {sup 134}Cs. The experimental sorption on the intact rock is compared with values calculated using the in house cation exchange sorption model (HYRL model) in PHREEQC program. The observed sorption on T-MGN and T-TGG rocks was close to the calculated values. Two PGR samples were from a depth of 70 m and three samples were from a depth of 150 m. Cesium sorbed more than predicted on the two 70 m PGR samples. The sorption of Cs on the three 150 m PGR samples was small which was consistent with the calculations. The pegmatitic granite PGR has the smallest content of biotite of the four rock types. In the case of P-TGG rock the observed values of sorption were only half of the calculated values. Two kind of slices were cut from P-TGG drill core. The slices were against and to the direction of the foliation of the biotite rims. The sorption of cesium on P-TGG rock was same in both cases. The results indicated that there was no effect of the directions of the electric field and the foliation of biotite in the P-TGG rock. (orig.)

  12. Time-resolved soft-x-ray spectroscopy of a magnetic octupole transition in nickel-like xenon, cesium, and barium ions

    Energy Technology Data Exchange (ETDEWEB)

    Trabert, E; Beiersdorfer, P; Brown, G V; Boyce, K; Kelley, R L; Kilbourne, C A; Porter, F S; Szymkowiak, A

    2005-11-11

    A microcalorimeter with event mode capability for time-resolved soft-x-ray spectroscopy, and a high-resolution flat-field EUV spectrometer have been employed at the Livermore EBIT-I electron beam ion trap for observations and wavelength measurements of M1, E2, and M3 decays of long-lived levels in the Ni-like ions Xe{sup 26+}, Cs{sup 27+}, and Ba{sup 28+}. Of particular interest is the lowest excited level, 3d{sup 9}4s {sup 3}D{sub 3}, which can only decay via a magnetic octupole (M3) transition. For this level in Xe an excitation energy of (590.40 {+-} 0.03eV) and a level lifetime of (11.5 {+-} 0.5 ms) have been determined.

  13. Rational Design of Cesium-Selective Ionophores and Chemosensors: Dihydrocalix[4]arene Crown-6 Ethers

    Energy Technology Data Exchange (ETDEWEB)

    Sachleben, Richard A.; Bryan, Jeffrey C.; Brown, Gilbert M.; Engle, Nancy L.; Haverlock, Tamara J.; Hay, Benjamin P.; Urvoas, Agathe; Moyer, Bruce A.

    2003-12-15

    Molecular mechanics calculations performed on calix[4]arene crown-6 ethers predict that the 1,3-dihydro derivatives will exhibit greater complementarity for potassium and cesium ions than the parent 1,3-dialkoxy calix crowns. The X-ray crystal structures of 1,3-alt bis-octyloxycalix[4]arene benzocrown-6 ether, dihydrocalix[4]arene benzocrown-6 ether, and the cesium nitrate complex of dihydrocalix[4]arene benzocrown-6 ether were determined. The cesium complex structure corresponds closely to the structure predicted by molecular mechanics. The dihydrocalix[4]arene crown-6 ethers exhibit enhanced cesium selectivity in the extraction of alkali metal salts and provide a platform for a highly sensitive and selective cesium chemosensor.

  14. Effect of diverse ions, column temperature and flow rate on the dynamic exchange-properties of cesium in various types of zeolites

    International Nuclear Information System (INIS)

    The effect of various diverse ions in solution, column temperature and flow rate on the dynamic exchange-properties of Cs have been studied with various types of zeolites, i.e., synthetic mordenite, natural mordenite and clinoptilolite. The concentration of nitric acid considerably affects on the break-through properties of Cs; break-through capacity (B. T. Cap), total capacity (T. Cap) and column utilization (U) decrease with increasing acid concentration. The break-throgh data in the pH range (pH >= 1) are as follows; above 50 (meq./100 g zeolite) for B. T. Cap, 110 (meq./100 g zeolite) for T. Cap and 45 (%) for U, respectively. On the other hand, the concentration of formic acid (<= 2 M) and sodium ion (<= 0.1 M) give no critical change on the break-through properties, and T. Cap was found to be nearly constant. Break-through capacity and exchange rate increase with an increase in column temperature, while T. Cap remains constant. Thus, a similar profile was found in the curves of these properties as a function of temperature. Their inflection point gives the value of C/Co asymptotically equals 0.63. The decrease in flow rate (S. V) appears to give an increase in both B. T. Cap and U. (author)

  15. Chemical and radiation stability of a proprietary cesium ion exchange material manufactured from WWL membrane and SuperLig{reg_sign} 644

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.N.; Carson, K.J.; DesChane, J.R.; Elovich, R.J.; Berry, P.K.

    1996-09-01

    Pretreatment of nuclear process wastes for ion exchange removal of Cs and other radionuclides is one way to minimize amount of high-level radioactive waste at Hanford. This study evaluated Cs-selective SuperLig{reg_sign}644 (IBC Advanced Technologies, American Fork UT) entrapped in a proprietary WWL web membrane (3M) for chemical/radiation stability in simulated caustic neutralized current acid waste (NCAW), 0.5M HNO{sub 3}, water, and air. After exposure up to 2.0E+09 rad, the material was evaluated for Cs uptake in 5M sodium NCAW simulants with varying Cs contents. Radiolytic stability appears to be sufficient for ion exchange pretreatment of radioactive Cs: essentially no decrease in Cs selectivity or loading (Kd) was observed during {sup 60}Cs gamma irradiation in water or 0.5M HNO{sub 3} up to 1.0E+09 rad. Cs Kd decreased by a factor of 2 after 2.0E+09 rad exposure. Cs Kd did not change during irradiation in 5M NCAW or ambient air up to 1.0E+08 rad, but decreased by more than an order of magnitude between 1.0E+08 and 2.0E+09 rad (not typical of process conditions). Chemical stability under caustic conditions is lower than in air or under neutral/acidic conditions. Results indicate that this material is less stable in caustic solution irrespective of radiation exposure. Samples of the membrane retained their physical form throughout the entire experiment and were only slightly brittle after exposure to 2.0E+09 rad. (The material evaluated was a finely ground (400 mesh) particulate engineered to form a polymeric fiber (WWL), not the macroscopic form of SuperLig{reg_sign} 644 resin (20 to 50 mesh).)

  16. Chemical and radiation stability of a proprietary cesium ion exchange material manufactured from WWL membrane and SuperLig reg-sign 644

    International Nuclear Information System (INIS)

    Pretreatment of nuclear process wastes for ion exchange removal of Cs and other radionuclides is one way to minimize amount of high-level radioactive waste at Hanford. This study evaluated Cs-selective SuperLig reg-sign 644 (IBC Advanced Technologies, American Fork UT) entrapped in a proprietary WWL web membrane (3M) for chemical/radiation stability in simulated caustic neutralized current acid waste (NCAW), 0.5M HNO3, water, and air. After exposure up to 2.0E+09 rad, the material was evaluated for Cs uptake in 5M sodium NCAW simulants with varying Cs contents. Radiolytic stability appears to be sufficient for ion exchange pretreatment of radioactive Cs: essentially no decrease in Cs selectivity or loading (Kd) was observed during 60Cs gamma irradiation in water or 0.5M HNO3 up to 1.0E+09 rad. Cs Kd decreased by a factor of 2 after 2.0E+09 rad exposure. Cs Kd did not change during irradiation in 5M NCAW or ambient air up to 1.0E+08 rad, but decreased by more than an order of magnitude between 1.0E+08 and 2.0E+09 rad (not typical of process conditions). Chemical stability under caustic conditions is lower than in air or under neutral/acidic conditions. Results indicate that this material is less stable in caustic solution irrespective of radiation exposure. Samples of the membrane retained their physical form throughout the entire experiment and were only slightly brittle after exposure to 2.0E+09 rad. (The material evaluated was a finely ground (400 mesh) particulate engineered to form a polymeric fiber (WWL), not the macroscopic form of SuperLig reg-sign 644 resin (20 to 50 mesh).)

  17. Evaluation and comparison of SuperLig{reg_sign} 644, resorcinol-formaldehyde and CS-100 ion exchange materials for the removal of cesium from simulated alkaline supernate

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.N.; Bray, L.A.; Eloviche, R.J. [Pacific Northwest Lab., Richland, WA (United States); Bruening, R.L.; Decker, R.M. [IBC Advanced Technologies, Inc., Provo, UT (United States); Kafka, T.M.; White, L.R. [3M Co., St. Paul, MN (United States)

    1995-03-01

    PNL evaluated three polymeric materials for Cs removal efficiency from a simulated Hanford Neutralized Current Acid Waste (NCAW) supernatant liquid using 200 mL ion exchange columns. Cs loadings (mmole Cs/g resin) were 0.20, 0.18, and 0.039 for Super Lig 644, R-F, and CS-100 (0.045, 0.070, 0.011 mmole Cs/mL resin). Elution of each resin material with 0.5 M HNO{sub 3} required 3.5, 7.0, and 3.2 cv to reach 0.1 C/C{sub 0} for the respective materials, resulting in volume compressions of 27, 20, and 6.9. Peak Cs concentrations during elution was 185, 38.5, and 27.8 C/C{sub 0}. SuperLig 644 had the highest Cs loading per gram in NCAW and the greatest volume compression on aci elution. Because of high density and poor elution, R-F had the highest Cs loading per unit volume and lower volume compression. CS-100, the baseline material for Cs removal at Hanford, was inferior to both SuperLig 644 and R-F in terms of Cs loading and selectivity over sodium.

  18. Distribution of cesium 137 between different sorption sites of soils contaminated by Chernobyl catastrophe products

    International Nuclear Information System (INIS)

    The results of investigation of distribution of cesium 137 ions between different sorption sites of soils contaminated by Chernobyl catastrophe products are received. Using NH42 and Sr2+ as ousted cations the portion of radionuclide adsorbed by specific (FES) and regular (RES) exchangeable sites have been determined. The distribution of cesium 137 ions and its exchangeable form between soils and liquid phases of water saturated soils have been established. The distribution coefficients have been evaluated. The behavior of cesium 137 in a system 'soil - solution' with different contribution of FES and RES sites into radionuclide adsorption were considered. Effect of solution acidity and cation concentration compete for exchangeable adsorption have been analyzed. Higher cesium 137 mobility during its transfer from solid phase into solution in soils, where content of specific adsorption sites is limited, was revealed

  19. Cesium Concentration in MCU Solvent

    International Nuclear Information System (INIS)

    During Modular Caustic-Side Solvent Extraction (CSSX) Unit (MCU) operations, Cs-137 concentrations in product streams will vary depending on the location in the process and on the recent process conditions. Calculations of cesium concentrations under a variety of operating conditions reveal the following: (1) Under nominal operations with salt solution feed containing 1.1 Ci Cs-137 per gallon, the maximum Cs-137 concentration in the process will occur in the strip effluent (SE) and equal 15-16.5 Ci/gal. (2) Under these conditions, the majority of the solvent will contain 0.005 to 0.01 Ci/gal, with a limited portion of the solvent in the contactor stages containing ∼4 Ci/gal. (3) When operating conditions yield product near 0.1 Ci Cs-137/gal in the decontaminated salt solution (DSS), the SE cesium concentration will be the same or lower than in nominal operations, but majority of the stripped solvent will increase to ∼2-3 Ci/gal. (4) Deviations in strip and waste stream flow rates cause the largest variations in cesium content: (a) If strip flow rates deviate by -30% of nominal, the SE will contain ∼23 Ci/gal, although the cesium content of the solvent will increase to only 0.03 Ci/gal; (b) If strip flow rate deviates by -77% (i.e., 23% of nominal), the SE will contain 54 Ci/gal and solvent will contain 1.65 Ci/gal. At this point, the product DSS will just reach the limit of 0.1 Ci/gal, causing the DSS gamma monitors to alarm; and (c) Moderate (+10 to +30%) deviations in waste flow rate cause approximately proportional increases in the SE and solvent cesium concentrations. Recovery from a process failure due to poor cesium stripping can achieve any low cesium concentration required. Passing the solvent back through the contactors while recycling DSS product will produce a ∼70% reduction during one pass through the contactors (assuming the stripping D value is no worse than 0.36). If the solvent is returned to the solvent hold tank (containing additional

  20. Efficient cesiation in RF driven surface plasma negative ion source

    Science.gov (United States)

    Belchenko, Yu.; Ivanov, A.; Konstantinov, S.; Sanin, A.; Sotnikov, O.

    2016-02-01

    Experiments on hydrogen negative ions production in the large radio-frequency negative ion source with cesium seed are described. The system of directed cesium deposition to the plasma grid periphery was used. The small cesium seed (˜0.5 G) provides an enhanced H- production during a 2 month long experimental cycle. The gradual increase of negative ion yield during the long-term source runs was observed after cesium addition to the source. The degraded H- production was recorded after air filling to the source or after the cesium washing away from the driver and plasma chamber walls. The following source conditioning by beam shots produces the gradual recovery of H- yield to the high value. The effect of H- yield recovery after cesium coverage passivation by air fill was studied. The concept of cesium coverage replenishment and of H- yield recovery due to sputtering of cesium from the deteriorated layers is discussed.

  1. Cesium exchange reaction on natural and modified clinoptilolite zeolites

    International Nuclear Information System (INIS)

    Cesium cation exchange reaction with K, Na, Ca and Mg ions on natural and modified clinoptilolite has been studied. Batch cation-exchange experiments were performed by placing 0.5 g of clinoptilolite into 10 ml or 20 ml of 1 x 10-3M CsCl solution for differing times. Two type deposits of clinoptilolite zeolites from, Nizny Hrabovec (NH), Slovakia and Metaxades (MX), Greece were used for ion-exchange study. The distribution coefficient (Kd) and sorption capacity (Γ) were evaluated. For the determination of K, Na, Ca and Mg isotachophoresis method, the most common cations in exchange reaction was used. Cesium sorption was studied using 137Cs tracer and measured by γ-spectrometry. (author)

  2. Cesium in the nutrient cycle

    International Nuclear Information System (INIS)

    Most radioactive cesium in forests is deposited in soil, from which it passes into berries and mushrooms, and further to game. The cesium contents of Finnish berries and mushrooms vary depending on the intensity of Chernobyl fallout. Northern Haeme, Pirkanmaa and parts of central Finland received the most fallout. Weather conditions and the environmental factors, and other circumstances during the growth period, also affect the contents. However, consumption of wild berries, mushrooms and game need not be restricted because of radioactivity anywhere in Finland

  3. Cesium contamination of heather honey

    International Nuclear Information System (INIS)

    In heather honey from Lueneburger Heide, FRG, relatively high values of cesium activity were found (up to about 650 Bq/kg). Activity values for heather honey, Calluna vulgaris plants and soil were measured. It is assumed that the origin of this activity is the direct Chernobyl fallout. There may also be a high transfer of cesium from the soil to the Calluna vulgaris plant, but in order to determine the transfer factor, fresh plants are needed, which have grown later than in spring 1986. (author) 21 refs.; 2 figs.; 2 tabs

  4. Preparation and use of polymeric materials containing hydrophobic anions and plasticizers for separation of cesium and strontium

    International Nuclear Information System (INIS)

    Preparation and use is described for polymeric materials containing hydrophobic anions and plasticizers for extraction of cesium and strontium. The use of polymeric materials containing plasticizers which are solvents for hydrophobic anions such as derivatives of cobalt dicarbollide or tetraphenylborate which are capable of extracting cesium and strontium ions from aqueous solutions in contact with the polymeric materials, is described. The polymeric material may also include a synergistic agent for a given ion like polyethylene glycol or a crown ether, for removal of radioactive isotopes of cesium and strontium from solutions of diverse composition and, in particular, for solutions containing large excess of sodium nitrate

  5. Hot demonstration of proposed commercial cesium removal technology

    International Nuclear Information System (INIS)

    This report describes the work done in support of the development of technology for the continuous removal and concentration of radioactive cesium in supernatant from Melton Valley Storage Tanks (MVSTs) at the ORNL site. The primary objective was to test candidate absorbers and ion exchangers under continuous-flow conditions using actual supernatant from the MVSTs. An experimental system contained in a hot-cell facility was constructed to test the materials in columns or modules using the same batch of supernatant to allow comparison on an equal basis. Resorcinol/formaldehyde (RF) resin was evaluated at three flow rates with 50% breakthrough ranges of 35 to 50 column volumes (CV) and also through a series of five loading/elution/regeneration cycles. The results reported here include the cesium loading breakthrough curves, elution curves (when applicable), and operational problems and observations for each material. The comparative evaluations should provide critical data for the selection of the sorbent for the ORNL Cesium Removal Demonstration project. These results will be used to help determine the design parameters for demonstration-scale systems. Such parameters include rates of cesium removal, quantity of resin or sorbent to be used, and elution and regeneration requirements, if applicable

  6. Cesium transport data for HTGR systems

    International Nuclear Information System (INIS)

    Cesium transport data on the release of cesium from HTGR fuel elements are reviewed and discussed. The data available through 1976 are treated. Equations, parameters, and associated variances describing the data are presented. The equations and parameters are in forms suitable for use in computer codes used to calculate the release of metallic fission products from HTGR fuel elements into the primary circuit. The data cover the following processes: (1) diffusion of cesium in fuel kernels and pyrocarbon, (2) sorption of cesium on fuel rod matrix material and on graphite, and (3) migration of cesium in graphite. The data are being confirmed and extended through work in progress

  7. Example of cesium sorption database in natural minerals

    International Nuclear Information System (INIS)

    In the database of the National Institute for Materials Science (MatNavi), the adsorption data of cesium, strontium, and iodine have been published. Among these data, the authors picked up the data of cesium adsorption against natural ores, which were measured and compiled by the authors, graphically expressed them for clarifying the overall trends, and described each mineral’s adsorption characteristics and future challenges. The partition coefficients for the following minerals are compiled: bentonite, acid clay, montmorillonite, beidellite, vermiculite, illite, mordenite, zeolite, etc. Many of the recorded data in MatNavi are the data obtained in the systems without existence of a large amount of competing ions. On the other hand, in the accumulated water at the Fukushima Daiichi Nuclear Power Station, competing ions due to seawater are contained. In the immersion liquid of incineration fly ash and the immersion liquid of plants/vegetation, too, competing ions are considered to be contained. Accumulation of adsorption data under different solution conditions are considered important. In addition, the concentrations of radioactive cesium in decontamination target are lower values by 5-7 orders, compared with the lower limit of 0.01 ppm in the existing data. In face of experiments, the influence of adsorption to containers and filters cannot be neglected. (A.O.)

  8. Review and assessment of technologies for the separation of cesium from acidic media

    International Nuclear Information System (INIS)

    A preliminary literature survey has been conducted to identify and evaluate methods for the separation of cesium from acidic waste. The most promising solvent extraction, precipitation, and ion exchange methods, along with some of the attributes for each method, are listed. The main criteria used in evaluating the separation methods were as follows: (1) good potential for cesium separation must be demonstrated (i.e., cesium decontamination factors on the order of 50 to 100). (2) Good selectivity for cesium over bulk components must be demonstrated. (3) The method must show promise for evolving into a practical and fairly simple process. (4) The process should be safe to operate. (5) The method must be robust (i.e., capable of separating cesium from various acidic waste types). (6) Secondary waste generation must be minimized. (7) The method must show resistance to radiation damage. The most promising separation methods did not necessarily satisfy all of the above criteria, thus key areas requiring further development are suggested for each method. The report discusses in detail these and other areas requiring further development, as well as alternative solvent extraction, precipitation, ion exchange, and open-quote other close-quote technologies that, based on current information, show less promise for the separation of cesium from acidic wastes because of significant process limitations. When appropriate, the report recommends areas of future development

  9. Separation of radio cesium from acid-Purex solutions by sorption on granulated AMP

    International Nuclear Information System (INIS)

    An organic polymer, poly vinylbutyral was used for the preparation of the composite exchanger containing ammonium molybdo phosphate (AMP) as the active component. The resultant granulated product (AMP-GR) has excellent column properties and stands high flow rates without generating fines. The method of preparation of the granulated sorbent, the batch and breakthrough capacities of the granules for cesium ions, their hydraulic properties and the results of column tests for cesium separation from acidic cesium solutions and simulated high level wastes (HLW) solutions is described. The process can be adapted to remove cesium from HLW solutions and could thus be incorporated in a waste management scheme. (author). 16 refs., 3 figs., 3 tabs

  10. Fission of Multiply Charged Cesium and Potassium Clusters in Helium Droplets - Approaching the Rayleigh Limit

    CERN Document Server

    Renzler, Michael; Daxner, Matthias; Kranabetter, Lorenz; Kuhn, Martin; Scheier, Paul; Echt, Olof

    2016-01-01

    Electron ionization of helium droplets doped with cesium or potassium results in doubly and, for cesium, triply charged cluster ions. The smallest observable doubly charged clusters are $Cs_{9}^{2+}$ and $K_{11}^{2+}$; they are a factor two smaller than reported previously. The size of potassium dications approaches the Rayleigh limit nRay for which the fission barrier is calculated to vanish, i.e. their fissilities are close to 1. Cesium dications are even smaller than nRay, implying that their fissilities have been significantly overestimated. Triply charged cesium clusters as small as $Cs_{19}^{3+}$ are observed; they are a factor 2.6 smaller than previously reported. Mechanisms that may be responsible for enhanced formation of clusters with high fissilities are discussed.

  11. Cold cesium molecules produced directly in a magneto-optical trap

    Institute of Scientific and Technical Information of China (English)

    Zhang Hong-Shan; Ji Zhong-Hua; Yuan Jin-Peng; Zhao Yan-Ting; Ma Jie; Wang Li-Rong; Xiao Lian-Tuan; Jia Suo-Tang

    2011-01-01

    We report on the observation of ultracold ground electric-state cesium molecules produced directly in a magnetooptical trap with a good signal-to-noise ratio.These molecules arise from the photoassociation of magneto-optical trap lasers and they are detected by resonantly enhanced multiphoton ionization technology.The production rate of ultracold cesium molecules is up to 4× 104 s-1.We measure the characteristic time of the ground electric-state cesium molecules generated in the experiment and investigate the Cs2+ molecular ion intensity as a function of the trapping laser intensity and the ionization pulse laser energy.We conclude that the production of cold cesium molecules may be enhanced by using appropriate experimental parameters,which is useful for future experiments involving the production and trapping of ultracold ground electric-state molecules.

  12. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium.

    Science.gov (United States)

    Hu, Baiyang; Fugetsu, Bunshi; Yu, Hongwen; Abe, Yoshiteru

    2012-05-30

    We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent. PMID:22464752

  13. Co-precipitation and solubility studies of cesium, potassium and sodium tetraphenylborate

    International Nuclear Information System (INIS)

    This report contains the results from a study requested by High Level Waste Division on the co-precipitation and solubility of cesium, potassium, and sodium tetraphenylborate. Co-precipitation of cesium (Cs), potassium (K), and sodium (Na) tetraphenylborate (TPB) helps determine the efficiency of reagent usage in the Small Tank Precipitation Process. This process uses NaTPB to remove cesium from waste by means of precipitation. Previous studies by McCabe suggested that if the sodium ion concentration [Na+] increased the rate at which cesium tetraphenylborate (KTPB) in the presence of high [Na+] (∼5M) appears to produce a mixed solid phase composed of NaTPB and KTPB together in the crystal lattice

  14. Preparation and characterization of cesium-137 aluminosilicate pellets for radioactive source applications

    International Nuclear Information System (INIS)

    Twenty-seven fully loaded 137Cs aluminosilicate pellets were fabricated in a hot cell by the vacuum hot pressing of a cesium carbonate/montmorillonite clay mixture at 15000C and 570 psig. Four pellets were selected for characterization studies which included calorimetric measurements, metallography, scanning electron microscope and electron backscattering (SEM-BSE), electron microprobe, x-ray diffraction, and cesium ion leachability measurements. Each test pellet contained 437 to 450 curies of 137Cs as determined by calorimetric measurements. Metallographic examinations revealed a two-phase system: a primary, granular, gray matrix phase containing large and small pores and small pore agglomerations, and a secondary fused phase interspersed throughout the gray matrix. SEM-BSE analyses showed that cesium and silicon were uniformly distributed throughout both phases of the pellet. This indicated that the cesium-silicon-clay reaction went to completion. Aluminum homogeneity was unconfirmed due to the high background noise associated with the inherent radioactivity of the test specimens. X-ray diffraction analyses of both radioactive and non-radioactive aluminosilicate pellets confirmed the crystal lattice structure to be pollucite. Cesium ion quasistatic leachability measurements determined the leach rates of fully loaded 137Cs sectioned pollucite pellets to date to be 4.61 to 34.4 x 10-10 kg m-2s-1, while static leach tests performed on unsectioned fully loaded pellets showed the leach rates of the cesium ion to date to be 2.25 to 3.41 x 10-12 kg m-2s-1. The cesium ion diffusion coefficients through the pollucite pellet were calculated using Fick's first and second laws of diffusion. The diffusion coefficients calculated for three tracer level 137Cs aluminosilicate pellets were 1.29 x 10-16m2s-1, 6.88 x 10-17m2s-1, and 1.35 x 10-17m2s-1, respectively

  15. Decorporation of cesium-137; Decorporation du cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Le Fleche, Ph.; Destombe, C.; Grasseau, A.; Mathieu, J.; Chancerelle, Y.; Mestries, J.C. [GMR, Direction des Recherches, Etudes et Techniques, 94 - Arcueil (France)

    1997-12-31

    Cesium radio-isotopes, especially cesium-137 ({sup 137}Cs) are among the radionuclides of main importance produced by a fission reaction in reactor or a nuclear weapon explosion. In the environment, {sup 137}Cs is a major contaminant which can cause severe {beta}, {gamma}irradiations and contaminations. {sup 137}Cs is distributed widely and relatively uniformly throughout the body with the highest concentration in skeletal muscles. A treatment becomes difficult afterwards. The purposes of this report are Firstly to compare the Prussian blue verses cobalt and potassium ferrocyanide (D.I. blue) efficiency for the {sup 137}Cs decorporation and secondly to assess a chronological treatment with D.I. blue. (author)

  16. First-principles study of cesium adsorption to weathered micaceous clay minerals

    Science.gov (United States)

    Okumura, Masahiko; Nakamura, Hiroki; Machida, Masahiko

    2014-05-01

    A large amount of radioactive nuclides was produced into environment due to the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident. Residents near FDNPP were suffering from radioactive cesium and then evacuated, because which has long half-life and is retained by surface soil for long time. The Japanese government has been decontaminating the cesium by removing the surface soil in order to return them to their home. This decontamination method is very effective, but which produces huge amount of waste soil. This becomes another big problem in Fukushima, because it is not easy to find large storage sites. Then effective and economical methods to reduce the volume of the waste soil are needed. However, it has not been invented yet. One of the reasons is lack of knowledge about microscopic process of adsorption/desorption of cesium to/from soil. It is known that weathered micaceous clay minerals play crucial role on adsorption and retention of cesium. They are expected to have special sorption sites, called frayed edge sites (FESs), which adsorb cesium selectively and irreversibly. Properties of FES have been intensely investigated by experiments. But microscopic details of the adsorption process on FES are still unclear. Because direct observation of the process with current experimental techniques is quite difficult. We investigated the adsorption of cesium to FES in muscovite, which is a typical micaceous clay mineral, via first-principles calculations (density functional theory). We made a minimal model of FES and evaluate the energy difference before and after cesium adsorption to FES. This is the first numerical modeling of FES. It was shown that FES does adsorb cesium if the weathering of muscovite has been weathered. In addition, we revealed the mechanism of cesium adsorption to FES, which is competition between ion radius of cesium and the degree of weathering. I plan to discuss volume reduction of the waste soil based on our result. Reference M. Okumura

  17. On specific features of thermoemission of cesium-implanted molybdenum monocrystals

    International Nuclear Information System (INIS)

    The influence of keeping in an electric field of the anode on the emission current of cesium ion doped molybdenum single crystal has been observed. An X-ray diffractometer has been used to show the formation of a new phase in the near-surface region of crystals after doping that is not identified with none of the known molybdenum compounds. The observed specific features of the thermoemission are attributed to a change of the work function of the crystal surface as a result of cesium ions migration in the lattice of the formed ternary chemical compound

  18. Separation of cesium from rad waste solutions with hexacyanoferrate(II) resins of copper and cobalt

    International Nuclear Information System (INIS)

    The separation of radiocesium from low and intermediate level waste solutions by ion exchange with potassium cobalt hexacyanoferrate(II) and potassium copper-cobalt hexacyanoferrate(II) loaded resins was studied. The distribution coefficient(Kd) of cesium as a function of sodium ion concentration was determined. High batch capacity of these resins with regards to cesium make them ideal sorbents that can be used in once through mode in the treatment of rad waste solutions. (author). 3 refs., 1 fig., 1 tab

  19. Contributions to the study of positive ion kinetics in gases

    International Nuclear Information System (INIS)

    Extensive studies on cesium ion kinetics in cesium and cesium-noble gas mixtures were performed. The obtained data are correlated with the measured parameters of the thermionic diodes. The mobility of atomic and molecular cesium ions at low electric fields, including zero electric field, in cesium and cesium krypton mixtures were measured using the time of flight method and a special thermionic ion detector. The atomic ion conversion into molecular ions is theoretically considered in the diffusion equation of the charged particles and the obtained analytical relation is in good agreement with the experimental cesium measured data. The reaction rate of the ion conversion in cesium is considered from these measurements. Measurements on the diffused plasma through the anode (provided with holes) of the cesium thermionic diode supply data on the anode sheath, the ratio of electronic and ionic current, electron temperature and the nature of the cesium ions (atomic or molecular) for various modes of the low voltage arc discharge. The obtained data have been used for the optimization of the thermionic diode parameters, as well as for the development of a new type of device for the detection of impurities in the air. (author)

  20. Migration behavior of cesium in compacted sodium montmorillonite

    International Nuclear Information System (INIS)

    For safety assessments of geological disposal of high-level radioactive wastes, it is important to study the migration behavior of radioactive nuclides in compacted bentonite. In the present study, the apparent diffusion coefficients and activation energies of the diffusion were determined for cesium ions in compacted montmorillonite, a major clay mineral in bentonite. The activation energies obtained in the present study were 32.9 to 52.9 kJ mol-1, clearly higher than for the diffusion of cesium ions in free water, 16.2 kJ mol-1. The activation energies for Na-montmorillonite specimens with dry densities of 1.0, 1.2, and 1.4 x 103 kg m-3 were similar at approximately 34 kJ mol-1. When the dry density of the Na-montmorillonite specimens increases, the activation energy also increases, to reach 52.9 kJ mol-1 at 1.8 x 103 kg m-3. These findings suggest that the cesium in the compacted Na-montmorillonite diffuses with a different process from that in free water. Basal spacings were determined by the X-ray diffraction method for water-saturated, compacted Na-montmorillonite specimens. Three-water layer hydrate in the interlamellar space was observed for the Na-montmorillonite with dry densities of 1.0, 1.2, and 1.4 x 103 kg m-3, where the activation energies for the diffusion were nearly constant. Only the two-water layer hydrate was found in the Na-montmorillonite with dry densities of 1.6 and 1.8 x 103 kg m-3, in which the activation energy increases with the dry density. It is possible that the basal spacing could affect the migration behavior of cesium in compacted Na-montmorillonite. (author)

  1. Extraction of radioactive cesium from tea leaves

    International Nuclear Information System (INIS)

    Radioactive contamination of foodstuffs attributed to the Fukushima Daiichi nuclear disaster has become a social problem. This study investigated the extraction of radioactive cesium from the contaminated leaves to the tea. The green tea was brewed twice reusing the same leaves to study the difference in extraction of cesium between the first and second brew. Moreover, the extraction of cesium was studied in correlation to brewing time. The concentration of radioactive cesium was determined with gamma spectrometry, and the concentration of caffeine was determined with absorption spectrometry. About 40% of cesium was extracted from leaves in the first brew, and about 80% was extracted in the second brew. The extraction of cesium increased over time, and it reached about 80% after 10 minutes brew. The ratio of radioactive cesium to caffeine decreased linearly over time. This study revealed that the extraction of cesium was higher for the second brew, and a rapid increase in extraction was seen as the tea was brewed for 6 minutes and more. Therefore, the first brew of green tea, which was brewed within 5 minutes, contained the least extraction of radioactive cesium from the contaminated leaves. (author)

  2. Cesium absorption from acidic solutions using ammonium molybdophosphate on a polyacrylonitrile support (AMP-PAN)

    International Nuclear Information System (INIS)

    Recent efforts at the Idaho Chemical Processing Plant (ICPP) have included evaluation of cesium removal technologies as applied to ICPP acidic radioactive waste streams. Ammonium molybdophosphate (AMP) immobilized on a polyacrylonitrile support (AMP-PAN) has been studied as an ion exchange agent for cesium removal from acidic waste solutions. Capacities, distribution coefficients, elutability, and kinetics of cesium-extraction have been evaluated. Exchange breakthrough curves using small columns have been determined from 1M HNO3 and simulated waste solutions. The theoretical capacity of AMP is 213 g Cs/kg AMP. The average experimental capacity in batch contacts with various acidic solutions was 150 g Cs/kg AMP. The measured cesium distribution coefficients from actual waste solutions were 3287 mL/g for dissolved zirconia calcines, and 2679 mL/g for sodium-bearing waste. The cesium in the dissolved alumina calcines was analyzed for; however, the concentration was below analytical detectable limits resulting in inconclusive results. The reaction kinetics are very rapid (2-10 minutes). Cesium absorption appears to be independent of acid concentration over the range tested (0.1 M to 5 M HNO3)

  3. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium

    International Nuclear Information System (INIS)

    Highlights: ► Prussian blue was sealed in cavities of diatomite using carbon nanotubes. ► The caged Prussian blue after being permanently immobilized in polyurethane spongy showed a 167 mg/g capability for absorbing cesium. ► Cesium elimination was accomplished by simply adding the Prussian-blue based spongiform adsorbent to radioactive water. - Abstract: We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent.

  4. Prussian blue caged in spongiform adsorbents using diatomite and carbon nanotubes for elimination of cesium

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Baiyang [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Fugetsu, Bunshi, E-mail: hu@ees.hokudai.ac.jp [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Yu, Hongwen [Graduate School of Environmental Science, Hokkaido University, Sapporo 060-0810 (Japan); Abe, Yoshiteru [Kyoei Engineering Corporation, Niigata 959-1961 (Japan)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer Prussian blue was sealed in cavities of diatomite using carbon nanotubes. Black-Right-Pointing-Pointer The caged Prussian blue after being permanently immobilized in polyurethane spongy showed a 167 mg/g capability for absorbing cesium. Black-Right-Pointing-Pointer Cesium elimination was accomplished by simply adding the Prussian-blue based spongiform adsorbent to radioactive water. - Abstract: We developed a spongiform adsorbent that contains Prussian blue, which showed a high capacity for eliminating cesium. An in situ synthesizing approach was used to synthesize Prussian blue inside diatomite cavities. Highly dispersed carbon nanotubes (CNTs) were used to form CNT networks that coated the diatomite to seal in the Prussian blue particles. These ternary (CNT/diatomite/Prussian-blue) composites were mixed with polyurethane (PU) prepolymers to produce a quaternary (PU/CNT/diatomite/Prussian-blue), spongiform adsorbent with an in situ foaming procedure. Prussian blue was permanently immobilized in the cell walls of the spongiform matrix and preferentially adsorbed cesium with a theoretical capacity of 167 mg/g cesium. Cesium was absorbed primarily by an ion-exchange mechanism, and the absorption was accomplished by self-uptake of radioactive water by the quaternary spongiform adsorbent.

  5. Activity of cesium-134 and cesium-137 in game and mushrooms in Poland

    International Nuclear Information System (INIS)

    The activity of cesium-134 and cesium-137 was measured in mushrooms and game in 1986-1991. The samples were collected all over Poland and most of the measurements were carried out for export purposes. The results indicate that the activity ratio of cesium-137 to cesium-134 in some samples is not comparable to that with fallout after the Chernobyl accident. The analysis of some samples of mushrooms from 1985 showed that the activity of cesium-137 was higher compared to any other foodstuff. The level of contamination varied greatly throughout Poland

  6. Selective chemical binding enhances cesium tolerance in plants through inhibition of cesium uptake

    Science.gov (United States)

    Adams, Eri; Chaban, Vitaly; Khandelia, Himanshu; Shin, Ryoung

    2015-03-01

    High concentrations of cesium (Cs+) inhibit plant growth but the detailed mechanisms of Cs+ uptake, transport and response in plants are not well known. In order to identify small molecules with a capacity to enhance plant tolerance to Cs+, chemical library screening was performed using Arabidopsis. Of 10,000 chemicals tested, five compounds were confirmed as Cs+ tolerance enhancers. Further investigation and quantum mechanical modelling revealed that one of these compounds reduced Cs+ concentrations in plants and that the imidazole moiety of this compound bound specifically to Cs+. Analysis of the analogous compounds indicated that the structure of the identified compound is important for the effect to be conferred. Taken together, Cs+ tolerance enhancer isolated here renders plants tolerant to Cs+ by inhibiting Cs+ entry into roots via specific binding to the ion thus, for instance, providing a basis for phytostabilisation of radiocesium-contaminated farmland.

  7. Selective chemical binding enhances cesium tolerance in plants through inhibition of cesium uptake

    DEFF Research Database (Denmark)

    Adams, Eri; Chaban, Vitaly; Khandelia, Himanshu; Shin, Ryoung

    2015-01-01

    High concentrations of cesium (Cs(+)) inhibit plant growth but the detailed mechanisms of Cs(+) uptake, transport and response in plants are not well known. In order to identify small molecules with a capacity to enhance plant tolerance to Cs(+), chemical library screening was performed using...... Arabidopsis. Of 10,000 chemicals tested, five compounds were confirmed as Cs(+) tolerance enhancers. Further investigation and quantum mechanical modelling revealed that one of these compounds reduced Cs(+) concentrations in plants and that the imidazole moiety of this compound bound specifically to Cs......(+). Analysis of the analogous compounds indicated that the structure of the identified compound is important for the effect to be conferred. Taken together, Cs(+) tolerance enhancer isolated here renders plants tolerant to Cs(+) by inhibiting Cs(+) entry into roots via specific binding to the ion thus, for...

  8. Co-precipitation and solubility studies of cesium, potassium and sodium tetraphenylborate

    International Nuclear Information System (INIS)

    This report contains the results from a study requested by High Level Waste on the co-precipitation and solubility of cesium, potassium, and sodium tetraphenylborate. Co-precipitation of cesium (Cs), potassium (K), and sodium (Na) tetraphenylborate (TPB) helps determine the efficiency of reagent usage in the Small Tank Precipitation Process. This process uses NaTPB to remove cesium from waste by means of precipitation. Previous studies by McCabe suggested that if the sodium ion concentration [Na+] increased the rate at which cesium tetraphenylborate (CsTPB) precipitates also increases. Serkiz also demonstrated that the precipitation of potassium tetraphenylborate (KTPB) in the presence of high [Na+] (∼5M) appears to produce a mixed solid phase composed of NaTPB and KTPB together in the crystal lattice. In the crystallographic structure of these three tetraphenylborate salts (Cs,K,NaTPB), the tetraphenylborate ion dominates the size of the crystals. Also, note that the three crystals have nearly identical structures with the exception of two additional peaks in the cesium pattern. Given these similarities, TPB precipitation in the presence of Na+, Cs+ and K+ likely produces an impure isomorphic crystalline mixture of CsTPB, KTPB and NaTPB. The authors speculate that the primary crystalline structure resembles that of KTPB with NaTPB and CsTPB mixed throughout the crystal structure. The precipitation of NaTPB makes some of the anticipated excess tetraphenylborate relatively unavailable for precipitation of cesium. Thus, the amount of excess tetraphenylborate required to completely precipitate all of the potassium and cesium may increase significantly

  9. PIXE analyses of cesium in rice grains

    Science.gov (United States)

    Sugai, Hiroyuki; Ishii, Keizo; Matsuyama, Shigeo; Terakawa, Atsuki; Kikuchi, Yohei; Takahashi, Hiroaki; Ishizaki, Azusa; Fujishiro, Fumito; Arai, Hirotsugu; Osada, Naoyuki; Karahashi, Masahiro; Nozawa, Yuichiro; Yamauchi, Shosei; Kikuchi, Kosuke; Koshio, Shigeki; Watanabe, Koji

    2014-01-01

    The Fukushima nuclear power plant accident released vast amounts of radioactive material into the environment. For instance, 134Cs and 137Cs have half-lives of about 2 and 30 years, respectively, and emit many harmful gamma rays. In 2012, rice with radioactivity >100 Bq/kg was occasionally reported in Fukushima prefecture. To determine where and how cesium accumulates in rice, we grew rice in soil containing stable cesium and investigated the distribution of cesium in rice using particle-induced X-ray emission (PIXE). This study found that cesium is accumulated in bran and germ at high concentrations, and white rice contains 40% of the cesium found in brown rice.

  10. Extended treatment of radiocontamination with cesium 137 by colloidal Prussian Blue. Test on a preparation which does not involve hepatic retention

    International Nuclear Information System (INIS)

    Prussian blue, which is applied per os, is recommended in radiocontamination treatment with cesium 137. It has been tried to increase product efficiency in using dispersed forms, such as ferrocyanide - anion - ion exchanger resins or colloidal form

  11. Cesium and strontium exchange properties of marsh soils

    International Nuclear Information System (INIS)

    The cesium and strontium exchange properties of some typical marsh soils of the estuary and lower river Weser region were described. Soil samples were taken according to the existing soil maps 1:25000 of Lower Saxony e.g. a “sea marsh soil”. a “brackish marsh soil”, and a “river marsh soil”. The exchange properties were determined by Cs/Ca and Sr/Ca exchange curves (Q/I relations) as generally used in soil potassium research. In addition to the Q/I relations the following investigations were carried out: - Cs and Sr desorption experiments (one time equilibration with Ca++ solutions) - Cs and Sr reexchange experiments (eight times equilibration with water, Ca++, Ba++, and K+ solutions) - the naturally-occuring Cs and Sr contents of the soils including amounts caused by imissions or fallout, respectively - clay mineral composition and swelling of layer silicates due to saturation with Ca++, Sr++, Cs+, and K+ ions. Q/I relations as well as desorption and reexchange experiments indicated strong cesium and low strontium fixation by the soils investigated. This was considered the reason for the stronger transfer of Sr from soil to plants as compared with Cs. Furthermore, the reexchange experiment revealed nearly complete reversibility of the Sr sorption reactions by equilibration with the divalent cations Ca++ and Ba++ and some Sr fixation after treatment with K+ solutions. However, cesium was much better reexchanged by K+ than by Ca++ and Ba++ ions. This led to the conclusion that Cs fixed in interlayer positions of clay minerals could be remobilized by potassium and ammonium fertilization. The naturally-occuring Cs contents of the soils were found to be below the detection limit of the analytical methods used. The contents of naturally-occuring exchangeable Sr, however, was in agreement with the amounts of “labile Sr” as derived from the Sr/Ca exchange curves. Concerning the cesium exchange properties a clear distinction between “sea and river marsh

  12. Investigation of thermoemission properties and elemental composition of cesium-implanted single crystal niobium surface

    International Nuclear Information System (INIS)

    The temperature dependences of work function and elemental composition of the surface of two samples of niobium single crystal doped by cesium ions are studied. The effects of decrease and increase of the emission current under the action of anodic potential are observed. Possible causes of the effects observed are discussed

  13. Industrial scale removal of cesium with hexacyanoferrate exchanger -- Process realization and test run

    International Nuclear Information System (INIS)

    At the Loviisa Nuclear Power Station (NPS) all liquid waste, i.e., spent resins and evaporator concentrates, have been stored in a large tank storage facility. Dominating radionuclides in the evaporator concentrates have been 134Cs and 137Cs. By removing cesium from the waste, purified liquid can be released within licensed release limits, and cobalt as a second dominating nuclide is left in a small waste volume on the bottom of the tank. Since 1985, the use of inorganic hexacyanoferrate-based materials for purification of cesium has been studied. A full-scale system for cesium removal, called the IVO-CsTreat System, was constructed in 1990 to 1991. A method to produce the ion exchanger in granular form in industrial scale was developed, and the facility to produce it was constructed. The ion exchange material was produced in 1991, and the full-scale purification facility was commissioned at the Loviisa NPS in October 1991. In the test run, 253 m3 of concentrate was purified between october 31, 1991 and June 11, 1992 with three ion exchange columns, each with a volume of 8 liters. A volume reduction factor of over 10,000 was achieved as the ratio of liquid and ion exchanger volume. The decontamination factor for cesium was ∼ 2,000

  14. Multiphoton ionization of atomic cesium

    International Nuclear Information System (INIS)

    We describe experimental studies of resonantly enhanced multiphoton ionization (MPI) of cesium atoms in the presence and absence of an external electric field. In the zero-field studies, photoelectron angular distributions for one- and two-photon resonantly enhanced MPI are compared with the theory of Tang and Lambropoulos. Deviations of experiment from theory are attributed to hyperfine coupling effects in the resonant intermediate state. The agreement between theory and experiment is excellent. In the absence of an external electric field, signal due to two-photon resonant three-photon ionization of cesium via np states is undetectable. Application of an electric field mixes nearby nd and ns levels, thereby inducing excitation and subsequent ionization. Signal due to two-photon excitation of ns levels in field-free experiments is weak due to their small photoionization cross section. An electric field mixes nearby np levels which again allows detectable photoionization signal. For both ns and np states the field induced MPI signal increases as the square of the electric field for a given principal quantum number and increases rapidly with n for a given field strength. Finally, we note that the classical two-photon field-ionization threshold is lower for the case in which the laser polarization and the electric field are parallel than it is when they are perpendicular. 22 references, 11 figures

  15. Method for removing cesium from aqueous liquid, method for purifying the reactor coolant in boiling water and pressurized water reactors and a mixed ion exchanged resin bed, useful in said purification

    International Nuclear Information System (INIS)

    The invention relates to a method for removing cesium from an aqueous liquid, and to a resin bed containing a mixture of an anion exchange resin and cation exchange resin useful in said purification. In a preferred embodiment, the present invention is a method for purifying the reactor coolant of a presurized water or boiling water reactor. Said method, which is particularly advantageously employed in purifying the reactor coolant in the primary circuit of a pressurized reactor, comprises contacting at least a portion of the reactor coolant with a strong base anion exchange resin and the strong acid cation exchange resin derived from a highly cross-linked, macroporous copolymer of a monovinylidene aromatic and a cross-linking monomer copolymerizable therewith. Although the reactor coolant can sequentially be contacted with one resin type and thereafter with the second resin type, the contact is preferably conducted using a resin bed comprising a mixture of the cation and anion exchange resins. 1 fig., refs

  16. Surface tension of liquid dilute solutions of lead-cesium and bismuth-cesium systems

    International Nuclear Information System (INIS)

    Method of the maximal pressure in a drop was used to measure the surface tension of 15 liquid dilute solutions of lead-cesium system in 0-0.214 at% concentration range and of 12 diluted solutions of bismuth-cesium system in 0-0.160 at.% cesium range from solidification temperature up to 500 dec C. It was found that cesium was characterized as surfactant in lead and bismuth melts. It was established that the temperature coefficient of surface tension changes sufficiently in maximally diluted solutions of alkali metals in bismuth and lead melts. Effect of sodium, potassium, rubidum and cesium on the value of surface tension of lead and bismuth was systematized. Growth of activity in sodium, potassium, rubidium and cesium series was noted

  17. Application of Cesium isotopes in daily life

    International Nuclear Information System (INIS)

    In the world of science, the desire of the scientific community to discover new chemical elements is crucial for the development of new technologies in various fields of knowledge. And the main chemical element addressed by this article is Cesium, but specifically 133Cesium isotope and radioisotope 137Cesium, exemplifying their physical and chemical characteristics, and their applications. This article will also show how these isotopes have provided researchers a breakthrough in the field of radiological medicine and in time and frequency metrology. (author)

  18. Decontamination of radioactive cesium in soil

    International Nuclear Information System (INIS)

    Agricultural soil containing radioactive cesium was decontaminated using an extraction method involving aqueous potassium solutions. Results demonstrated that the potassium solution could extract radioactive cesium from soil artificially contaminated with 137Cs, although extraction rate decreased as time after contamination increased. However, visual examination of radioactivity distribution in soil samples significantly contaminated by the accident at the Fukushima Daiichi nuclear power plant showed that radioactive cesium also existed as insoluble particles. Therefore, reducing the volume of radioactive wastes generated from soil decontamination requires a physical decontamination method combined with chemical treatment. (author)

  19. Sorption of cesium on Latvian clays

    International Nuclear Information System (INIS)

    Cesium is like potassium - good solubility and mobile in a ground, easily assimilate in organism expressly brawn woof. It is a problem if pollutant is a radioactive 137Cs. We made experiments to sorption a 2M CsF solution on some Latvian clays which mainly contain hydro micas (cesium content after good elute of clays are in table). We establish, that clay treated with 25 % sulfuric acid adsorb cesium two times more that waste clay. Hereto unstuck elute Cs from clays. (author)

  20. Removal of cesium using coconut fiber in raw and modified forms for the treatment of radioactive liquid wastes

    International Nuclear Information System (INIS)

    Sorption is one of the most studied methods to reduce the volume of radioactive waste streams. Cesium-137 is a radioisotope formed by the fission of uranium and it can cause health problems due to its easy assimilation by cells. The aim of this study is to evaluate the potential of coconut fiber in removing cesium from radioactive liquid wastes; this process can help in disposing radioactive waste. The experiments were performed in batch and the particle size of the fiber ranged between 0.30 mm and 0.50 mm. The fiber was treated with hydrogen peroxide in alkaline medium. The following parameters were analyzed: contact time, pH and concentration of cesium ions in aqueous solution. After the experiments the samples were filtered and cesium remaining in solution was quantified by inductively coupled plasma optical emission spectrometry. (author)

  1. Removal of cesium using coconut fiber in raw and modified forms for the treatment of radioactive liquid wastes

    Energy Technology Data Exchange (ETDEWEB)

    Jesus, Nella N.M. de; Nobre, Vanessa B.; Potiens Junior, Ademar J.; Sakata, Solange K., E-mail: sksakata@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Di Vitta, Patricia B. [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Quimica

    2013-07-01

    Sorption is one of the most studied methods to reduce the volume of radioactive waste streams. Cesium-137 is a radioisotope formed by the fission of uranium and it can cause health problems due to its easy assimilation by cells. The aim of this study is to evaluate the potential of coconut fiber in removing cesium from radioactive liquid wastes; this process can help in disposing radioactive waste. The experiments were performed in batch and the particle size of the fiber ranged between 0.30 mm and 0.50 mm. The fiber was treated with hydrogen peroxide in alkaline medium. The following parameters were analyzed: contact time, pH and concentration of cesium ions in aqueous solution. After the experiments the samples were filtered and cesium remaining in solution was quantified by inductively coupled plasma optical emission spectrometry. (author)

  2. Physical Property Modeling of Concentrated Cesium Eluate Solutions, Part I - Derivation of Models

    Energy Technology Data Exchange (ETDEWEB)

    Choi, A.S.; Pierce, R. A.; Edwards, T. B.; Calloway, T. B.

    2005-09-15

    Major analytes projected to be present in the Hanford Waste Treatment Plant cesium ion-exchange eluate solutions were identified from the available analytical data collected during radioactive bench-scale runs, and a test matrix of cesium eluate solutions was designed within the bounding concentrations of those analytes. A computer model simulating the semi-batch evaporation of cesium eluate solutions was run in conjunction with a multi-electrolyte aqueous system database to calculate the physical properties of each test matrix solution concentrated to the target endpoints of 80% and 100% saturation. The calculated physical properties were analyzed statistically and fitted into mathematical expressions for the bulk solubility, density, viscosity, heat capacity and volume reduction factor as a function of temperature and concentration of each major analyte in the eluate feed. The R{sup 2} of the resulting physical property models ranged from 0.89 to 0.99.

  3. Immobilisation and solidification of cesium on 11 A calcium silicate hydroxy hydrate column

    International Nuclear Information System (INIS)

    Calcium silicate hydrate closely resembling silicate mineral 11 A tobermorite has been synthesised by hydrothermal treatment of lime and silica at 175 degC. The synthetic mineral exhibits selectivity for Cs+ in the presence of strong solutions of alkali and alkaline earth cations, viz, Na+, K+, Mg2+, Ca2+, Sr2+, etc. The Al-substituted form of this mineral effectively separates cesium ion when used as an exchanger in column of size 35x5 mm (hxr). It is possible to remove 98.65±0.5%Cs+ from a mixed solution of cesium and sodium (0.0001N Cs+ + 0.5N Na+). Column separation of cesium from simulated intermediate level waste solution shows that from the first run ∼ 76% Cs+ can be immobilised on a small column, 18x10mm (hxr), having 2.0 g of exchanger. (author)

  4. Cesium Eluate Evaporation Solubility and Physical Property Behavior

    International Nuclear Information System (INIS)

    The baseline flowsheet for low activity waste (LAW) in the Hanford River Protection Project (RPP) Waste Treatment Plant (WTP) includes pretreatment of supernatant by removing cesium using ion exchange. When the ion exchange column is loaded, the cesium will be eluted with a 0.5M nitric acid (HNO3) solution to allow the column to be conditioned for re-use. The cesium eluate solution will then be concentrated in a vacuum evaporator to minimize storage volume and recycle HNO3. To prevent the formation of solids during storage of the evaporator bottoms, criteria have been set for limiting the concentration of the evaporator product to 80 percent of saturation at 25 degrees C. A fundamental element of predicting evaporator product solubility is to collect data that can be used to estimate key operating parameters. The data must be able to predict evaporator behavior for a range of eluate concentrations that are evaporated to the point of precipitation. Parameters that were selected for modeling include solubility, density, viscosity, thermal conductivity, and heat capacity. Of central importance is identifying the effect of varying feed components on overall solubility. The point of solubility defines the upper limit for eluate evaporation operations and liquid storage. The solubility point also defines those chemical compounds that have the greatest effects on physical properties. Third, solubility behavior identifies intermediate points where physical property data should be measured for the database. Physical property data (density, viscosity, thermal conductivity, and heat capacity) may be an integral part of tracking evaporator operations as they progress toward their end point. Once the data have been collected, statistical design software can develop mathematical equations that estimate solubility and other physical properties

  5. Method for monitoring radioactive cesium concentration in water using cesium adsorption disk and GM survey meter

    International Nuclear Information System (INIS)

    A method for monitoring radioactive cesium concentration in water using a cesium adsorption disk and a GM survey meter has been developed to ascertain whether the water quality meets standards on radiological contaminants in water. In this method, both dissolved and suspended forms of radioactive cesium are collected on the cesium adsorption disk by means of filtration of a water sample. Beta count rate of the disk is converted into radioactivity using a conservative calibration factor obtained here. The present method was applied to monitoring of decontaminated water of an outdoor school swimming pool in Date City after Fukushima Daiichi Nuclear Power Plant accident. (author)

  6. Trapping characteristics for gaseous cesium generated from different cesium compounds by fly ash filter

    International Nuclear Information System (INIS)

    The purpose of this study is to evaluate the applicability of the fly ash ceramic foam filter to trap gaseous cesium generated during the OREOX and sintering processes of DUPIC green pellets. The trapping experiments of gaseous cesium generated from different cesium compounds using fly ash filters were carried out in a two-zone furnace under air and hydrogen (Ar/4% H2) conditions. XRD and SEM analyses were used to analyze reaction products of different cesium compounds with fly ash filters. To manufacture ceramic foam filters, fly ash with a Si/Al mole ratio of 2.1 and polyvinyl alcohol as binder were used. Reaction products formed by the trapping reaction of different cesium compounds with fly ash filters were investigated. The major reaction products of gaseous cesium generated from cesium silicate and CsI by fly ash filters indicated that pollucite (CsAlSi2O6) phase was formed under air and hydrogen conditions when the carrier gas velocity was 2 cm/sec. The minimum reaction temperature of fly ash filter with gaseous cesium was determined as about 600 deg. C. Finally, off-gas treatment system of sintering process in a hot cell of lMEF was explained as an application example of fly ash filter for trapping gaseous cesium. (author)

  7. Preparation of Modified Kaolin Filler with Cesium and Its Application in Security Paper

    Directory of Open Access Journals (Sweden)

    Houssni El-Saied

    2013-01-01

    Full Text Available In this study, cesium was added intentionally during paper manufacture for protecting the papers against forgery and counterfeiting by sorbing cesium ions (Cs+ on kaolin, used as special filler in papermaking. The sorption of cesium from aqueous solution by kaolin was studied as a function of pH, shaking time, cesium initial concentration, and mass of kaolin using batch technique. The results showed that a solution containing 10 mg/L Cs+ and 250 mg of kaolin at pH 6 can be used to modify the kaolin. Paper handsheets were prepared containing various percentages of the modified kaolin. The mechanical and optical properties of paper handsheets were studied. The prepared paper handsheets were irradiated by gamma irradiation using different doses. Fourier transform infrared (FTIR spectroscopy was used to study the effect of kaolin modification by cesium and gamma irradiation on paper handsheets properties. The results indicated that modified kaolin enhanced the mechanical and optical properties of paper handsheets. Electron spin resonance (ESR spectroscopy and laser-induced breakdown spectroscopy (LIBS were also used. They provided rapid, sensitive and nondestructive techniques in differentiating between different questioned documents. This study presents a new concept in manufacturing security papers and anticounterfeiting applications.

  8. Sintered wire cesium dispenser photocathode

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, Eric J; Ives, R. Lawrence; Falce, Louis R

    2014-03-04

    A photoelectric cathode has a work function lowering material such as cesium placed into an enclosure which couples a thermal energy from a heater to the work function lowering material. The enclosure directs the work function lowering material in vapor form through a low diffusion layer, through a free space layer, and through a uniform porosity layer, one side of which also forms a photoelectric cathode surface. The low diffusion layer may be formed from sintered powdered metal, such as tungsten, and the uniform porosity layer may be formed from wires which are sintered together to form pores between the wires which are continuous from the a back surface to a front surface which is also the photoelectric surface.

  9. Alternate Methods for Eluting Cesium from Spherical Resorcinol-Formaldehyde Resin

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Paul Allen [ORNL; Johnson, Heather Lauren [University of Tennessee, Knoxville (UTK)

    2009-02-01

    A small-column ion exchange (SCIX) system has been proposed for removing cesium from the supernate and dissolved salt solutions in the high-level-waste tanks at the Savannah River Site (SRS). The SCIX system could use either crystalline silicotitanate (CST), an inorganic, non-regenerable sorbent, or spherical resorcinol-formaldehyde (RF), a new regenerable resin, to remove cesium from the waste solutions. The baseline method for eluting the cesium from the RF resin uses 15 bed volumes (BV) of 0.5 M nitric acid (HNO{sub 3}). The nitric acid eluate, containing the radioactive cesium, would be combined with the sludge from the waste tanks and would be converted into glass at the Defense Waste Processing Facility (DWPF) at SRS. The amount of nitric acid that would be used to elute the RF resin, using the current elution protocol, exceeds the capacity of DWPF to destroy the nitrate ions and maintain the required chemical reducing environment in the glass melt. Installing a denitration evaporator at SRS is technically feasible but would add considerable cost to the project. Alternate methods for eluting the resin have been tested, including using lower concentrations of nitric acid, other acids, and changing the flow regimes. About 4 BV of 0.5 M HNO{sub 3} are required to remove the sodium (titrate the resin) and most of the cesium from the resin, so the bulk of the acid used for the baseline elution method removes a very small quantity of cesium from the resin. A summary of the elution methods that have been tested are listed.

  10. Sorption of Cesium on Latvia clays

    International Nuclear Information System (INIS)

    Cesium is like potassium - good solubility and mobile in a ground, easy assimilates in organism expressly brawn woof. It is a problem if pollutant is radioactive 137Cs. We made experiments to sorption a 2M CsF solution on some Latvian clays which mainly contain hydro micas. We establish that clay treated with 25% sulfuric acid absorb cesium two times more that waste clay. Hereto unstuck elute Cs from clays

  11. Adsorption of uranium, cesium and strontium onto coconut shell activated carbon

    International Nuclear Information System (INIS)

    The adsorption of uranium (VI), cesium and strontium ions from aqueous solutions onto a commercial activated carbon obtained by physical activation of coconut shell has been studied in batch systems. In particular the adsorption of uranium, studied as a function of contact time and metal ion concentration, followed pseudo-first-order kinetics. Equilibrium adsorption data were fitted by Langmuir and Freundlich isotherm models and the maximum adsorption capacity of the activated carbon resulted to be 55.32 mg/g. The study showed that the considered activated carbon could be successfully used for uranium adsorption from aqueous solutions. Feasibility of cesium and strontium adsorption onto the same activated carbon has been also investigated. Results showed that no affinities with both of these ions exist. (author)

  12. Cs+ ion source for secondary ion mass spectrometry

    International Nuclear Information System (INIS)

    Various types of cesium ionization sources currently used in secondary ion mass spectrometry are briefly reviewed, followed by a description of the design and performance of a novel, thermal surface ionization Cs+ source developed in this laboratory. The source was evaluated for secondary ion mass spectrometry applications using the COALA ion microprobe mass analyzer. (orig.)

  13. Preparation and characterization of cesium-137 aluminosilicate pellets for radioactive source applications

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, F.J.; Tompkins, J.A.; Haff, K.W.; Case, F.N.

    1981-07-01

    Twenty-seven fully loaded /sup 137/Cs aluminosilicate pellets were fabricated in a hot cell by the vacuum hot pressing of a cesium carbonate/montmorillonite clay mixture at 1500/sup 0/C and 570 psig. Four pellets were selected for characterization studies which included calorimetric measurements, metallography, scanning electron microscope and electron backscattering (SEM-BSE), electron microprobe, x-ray diffraction, and cesium ion leachability measurements. Each test pellet contained 437 to 450 curies of /sup 137/Cs as determined by calorimetric measurements. Metallographic examinations revealed a two-phase system: a primary, granular, gray matrix phase containing large and small pores and small pore agglomerations, and a secondary fused phase interspersed throughout the gray matrix. SEM-BSE analyses showed that cesium and silicon were uniformly distributed throughout both phases of the pellet. This indicated that the cesium-silicon-clay reaction went to completion. Aluminum homogeneity was unconfirmed due to the high background noise associated with the inherent radioactivity of the test specimens. X-ray diffraction analyses of both radioactive and non-radioactive aluminosilicate pellets confirmed the crystal lattice structure to be pollucite. Cesium ion quasistatic leachability measurements determined the leach rates of fully loaded /sup 137/Cs sectioned pollucite pellets to date to be 4.61 to 34.4 x 10/sup -10/ kg m/sup -2/s/sup -1/, while static leach tests performed on unsectioned fully loaded pellets showed the leach rates of the cesium ion to date to be 2.25 to 3.41 x 10/sup -12/ kg m/sup -2/s/sup -1/. The cesium ion diffusion coefficients through the pollucite pellet were calculated using Fick's first and second laws of diffusion. The diffusion coefficients calculated for three tracer level /sup 137/Cs aluminosilicate pellets were 1.29 x 10/sup -16/m/sup 2/s/sup -1/, 6.88 x 10/sup -17/m/sup 2/s/sup -1/, and 1.35 x 10/sup -17/m/sup 2/s/sup -1

  14. Sorption of cesium on bentonite: The role of calcite

    International Nuclear Information System (INIS)

    Full text: Since bentonite is investigated for its use in Engineered Barriers Systems as backfill material, many studies of their surfaces properties have been performed in the past years to qualify and quantify adsorption on their surfaces, which can be one of the major processes limiting migration of radionuclides away from a disposal site. Nevertheless, most of these studies concerned simplified systems, such as Na-montmorillonite in mono-electrolyte solution. As ion-exchange processes are of importance in water-clays interactions, adsorption of natural major ions has also to be taken into account for natural systems. The aim of this work is (i) to quantify the sorption of the natural major cations on the montmorillonite surface, (ii) to compare the sorption of cesium, in two different systems, a simple one (Na-montmorillonite in NaNO3 0.05 Mol.L-1) and a complex one (natural bentonite in a synthetic natural water) and then (iii) to assess the influence of the natural major ions on this sorption, and to identify the role of the calcite phase present in bentonite. The methodology used consists in several batch experiments, first considering a very simple solution (NaNO3), then using mixtures of two different electrolytes, and lastly using a synthetic natural water. A surface complexation model, describing the surface of clays as a mixture of ion-exchange and complexation surface sites, is used to provide interpretations and quantifications of the sorption processes. Observed results indicate that affinity for the montmorillonite surface is greatest for Ca, then Mg and then K. The sorption of cesium is strongly affected by the presence in solution of Ca, witch can come from the partial dissolution of calcite. (author)

  15. Sorption of cesium on bentonite: The role of calcite

    International Nuclear Information System (INIS)

    Full text: Since bentonite is investigated for its use in Engineered Barriers Systems as backfill material, many studies of their surfaces properties have been performed in the past years to qualify and quantify adsorption on their surfaces, which can be one of the major processes limiting migration of radionuclides away from a disposal site. Nevertheless, most of these studies concerned simplified systems, such as Na-montmorillonite in mono-electrolyte solution. As ion-exchange processes are of importance in water-clays interactions, adsorption of natural major ions has also to be taken into account for natural systems. The aim of this work is (i) to quantify the sorption of the natural major cations on the montmorillonite surface; (ii) to compare the sorption of cesium, in two different systems, a simple one ( Na-montmorillonite in NaNO3 0.05 Mol.L-1) and a complex one (natural bentonite in a synthetic natural water) and then; (iii) to assess the influence of the natural major ions on this sorption, and to identify the role of the calcite phase present in bentonite. The methodology used consists in several batch experiments, first considering a very simple solution (NaNO3), then using mixtures of two different electrolytes, and lastly using a synthetic natural water. A surface complexation model, describing the surface of clays as a mixture of ion-exchange and complexation surface sites, is used to provide interpretations and quantifications of the sorption processes. Observed results indicate that affinity for the montmorillonite surface is greatest for Ca, then Mg and then K. The sorption of cesium is strongly affected by the presence in solution of Ca, witch can come from the partial dissolution of calcite. This study is one part of a work supported by ANDRA on the retention properties of bentonite materials. (author)

  16. Metabolism of 137cesium, 137barium in the rat. Therapeutics of the contamination

    International Nuclear Information System (INIS)

    The authors carry out research into the distribution kinetics, the metabolism and the excretion of 137Cs - 137Ba in the rat. They show that these phenomena are independent of the method of applying a single dose. The distribution tends to adopt in all cases a typical shape which remains the same depending on the body burden. Biological analysis of the state of the cesium in the biological media shows that it is transported in the free and ionised form. Considering the problem of the method of penetration of the cesium ion in the intracellular medium, and in particular by the in vivo and in vitro kinetic study of the plasma - red cell system, the authors make the assumption that an active transport of cesium occurs by the cell membrane. They thus arrive at an overall picture of the cesium distribution in the organism which is essentially characterized by a dynamic distribution equilibrium between two compartments: 99 per cent of the cesium accumulates in the intracellular pool, 1 per cent in the extracellular liquids. This latter compartment is open to the emunctories. Because, of the active transport by the cell membranes, the intracellular pool is filled rapidly but discharge is slow. This phenomenon is the limiting factor in the decrease of the body burden. From this representation, the authors deduce the reasons for the relative failure of the various therapeutic methods examined up till now by themselves or by other authors. The stimulation of the natural emunctories in the case of diuretics for example, can only improve the purification of the extracellular compartment. Now this latter contains only 1 per cent of the body burden and recharging is slow. Furthermore the methods designed to counteract or inhibit the active transport of cesium by the cell membrane are still at the present time incompatible with the survival of the cell. (authors)

  17. Facile Synthesis of Prussian Blue Derivate-Modified Mesoporous Material via Photoinitiated Thiol-Ene Click Reaction for Cesium Adsorption.

    Science.gov (United States)

    Qian, Jun; Ma, Jiaqi; He, Weiwei; Hua, Daoben

    2015-08-01

    A novel strategy to synthesize a functional mesoporous material for efficient removal of cesium is reported. Specifically, Prussian blue derivate-modified SBA-15 (SBA-15@FC) was prepared by photoinitiated thiol-ene reaction between thiol-modified SBA-15 and pentacyano(4-vinyl pyridine)ferrate complex. The effects of weight percentage of the Prussian blue derivate, pH, adsorbent dose, co-existing ions, and initial concentration were evaluated on the adsorption of cesium ions. The adsorption kinetically follows a pseudo-second-order model and reaches equilibrium within 2 h with a high adsorption capacity of about 13.90 mg Cs g(-1) , which indicates that SBA-15@FC is a promising adsorbent to effectively remove cesium from aqueous solutions. PMID:25965318

  18. An Inorganic Microsphere Composite for the Selective Removal of Cesium 137 from Acidic Nuclear Waste Solutions - Parts 1 and 2

    Energy Technology Data Exchange (ETDEWEB)

    T. J. Tranter; T. A. Vereschchagina; V. Utgikar

    2009-03-01

    A new inorganic ion exchange composite for removing radioactive cesium from acidic waste streams has been developed. The new material consists of ammonium molybdophosphate, (NH4)3P(Mo3O10)4•3H2O (AMP), synthesized within hollow aluminosilicate microspheres (AMP-C), which are produced as a by-product from coal combustion. The selective cesium exchange capacity of this inorganic composite was evaluated in bench-scale column tests using simulated sodium bearing waste solution as a surrogate for the acidic tank waste currently stored at the Idaho National Laboratory (INL). Total cesium loading on the columns at saturation agreed very well with equilibrium values predicted from isotherm experiments performed previously. A numerical algorithm for solving the governing partial differential equations (PDE) for cesium uptake was developed using the intraparticle mass transfer coefficient obtained from previous batch kinetic experiments. Solutions to the governing equations were generated to obtain the cesium concentration at the column effluent as a function of throughput volume using the same conditions as those used for the actual column experiments. The numerical solutions of the PDE fit the column break through data quite well for all the experimental conditions in the study. The model should therefore provide a reliable prediction of column performance at larger scales. A new inorganic ion exchange composite consisting of ammonium molybdophosphate, (NH4)3P(Mo3O10)4•3H2O (AMP), synthesized within hollow aluminosilicate microspheres (AMP-C) has been developed. Two different batches of the sorbent were produced resulting in 20% and 25% AMP loading for two and three loading cycles, respectively. The selective cesium exchange capacity of this inorganic composite was evaluated using simulated sodium bearing waste solution as a surrogate for the acidic tank waste currently stored at the Idaho National Laboratory (INL). Equilibrium isotherms obtained from these experiments

  19. Crown bridged thiacalix[4]arenes as cesium-selective ionophores in solvent polymeric membrane electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Bereczki, Robert [Technical Analytical Research Group of the Hungarian Academy of Sciences, Department of General and Analytical Chemistry, Budapest University of Technology and Economics, Szt. Gellert ter 4, H-1111 Budapest (Hungary); Csokai, Viktor [Department of Organic Chemical Technology, Budapest University of Technology and Economics, Muegyetem rkp.3, H-1111 Budapest (Hungary); Gruen, Alajos [Department of Organic Chemical Technology, Budapest University of Technology and Economics, Muegyetem rkp.3, H-1111 Budapest (Hungary); Bitter, Istvan [Department of Organic Chemical Technology, Budapest University of Technology and Economics, Muegyetem rkp.3, H-1111 Budapest (Hungary); Toth, Klara [Technical Analytical Research Group of the Hungarian Academy of Sciences, Department of General and Analytical Chemistry, Budapest University of Technology and Economics, Szt. Gellert ter 4, H-1111 Budapest (Hungary)]. E-mail: ktoth@mail.bme.hu

    2006-05-31

    Novel 1,3-alternate thiacalix[4]mono- and biscrown-6 ethers were studied as ionophores in poly(vinyl chloride) membrane electrodes. Their selectivity behavior was characterized with respect to large number of cations, including potential interferents in environmental samples, and the membrane composition was optimized for cesium ion response. Among the ionophores, 1,3-alternate thiacalix[4]mono(crown-6) ether showed, especially high selectivity for cesium over other alkali-metal ions. Transition and heavy metal ions did not interfere seriously with the electrode response, which indicates that the bridging sulfur atoms do not take part in the ion recognition process. The potentiometric cesium responses of all electrodes involved in this study were found close to Nernstian and the detection limits were lower than 10{sup -7} M. The Cs{sup +}/Na{sup +} selectivity of the different ionophore-based sensors and the solvent extraction ability of the ligands were interpreted based on the respective constants of complex formation.

  20. Inter-digitated electrode array based sensors for monitoring of cesium - 16123

    International Nuclear Information System (INIS)

    The requirement for on-line and in-situ monitoring of analytes in process and effluent streams and in ground waters has become increasingly more important in recent years. We therefore describe the development of the transduction element for a fully automated online instrument for the detection of cesium. The sensor layer for this instrument employs an Ion Selective Conductimetric microsensor (ISCOM) as the detector. This is based upon a plasticised polymeric membrane incorporating a selective ionophore, overlaying two inter-digitated microelectrode arrays. A direct relationship has been observed between the bulk conductance (as determined by the microelectrodes) of the ionophore loaded membrane and the concentration of the primary ions in solution. Cesium selective ISCOMs were prepared using a ion selective membrane containing the commercially available ionophore Calix[6]arene-hexa-acetic acid hexaethyl ester, polyvinylchloride (PVC) and plasticiser Nitro-phenylether (NPOE). Methods of ion selective membrane deposition have been investigated in order to obtain a maximal response. The relative levels of membrane components have also been varied in order to further enhance the ISCOM response. We also present preliminary data concerning the cesium selectivity with respect to a range of possible interferents, including rubidium. (authors)

  1. Studies on cesium sorption in hydrous zirconium and titanium oxides

    International Nuclear Information System (INIS)

    Significant quantities of 137Cs (T1/2 = 30.1 y) and 90Sr (T1/2 = 28.5 y) are produced as fission products in nuclear reactors. These long-lived gamma-emitting radionuclides, regarded as a waste few decades ago, are being termed now as valuables owing to the upsurge in the utilization of these radioisotopes in the area of medicine, food irradiation, and sewage treatment technologies in recent years. For long-term waste management it is necessary to minimize the volume and toxicity of the waste. Selective recovery and utilization of these radionuclides from the waste is the concept of growing interest to many researchers. Inorganic sorbents are proven candidates for the separation and recovery of cesium and strontium from aqueous waste streams. They are chemically durable and stable against ionizing radiation. In addition, these materials can be converted into unleachable ceramic form for final disposal. Hydrous metal oxides belong to a particular class of inorganic ion exchangers extensively investigated for various applications in nuclear waste treatment. The present study deals with the preparation of hydrous zirconium and titanium oxide and the studies aimed at separation of cesium from aqueous wastes

  2. Desorption of cesium from granite under various aqueous conditions

    Energy Technology Data Exchange (ETDEWEB)

    Wang, T.-H. [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China); Li, M.-H. [Institute of Hydrological and Oceanic Sciences, National Central University, Jungli 320, Taiwan (China); Wei, Y.-Y. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 300, Taiwan (China); Teng, S.-P., E-mail: spteng@ess.nthu.edu.t [Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 300, Taiwan (China)

    2010-12-15

    In this work the desorption of cesium ions from crushed granite in synthetic groundwater (GW) and seawater (SW) was investigated. Results were compared with those obtained in deionized water (DW) and in two kinds of extraction solutions, namely: MgCl{sub 2} and NaOAc (sodium acetate). In general, the desorption rate of Cs from crushed granite increased proportionally with initial Cs loadings. Also, amounts of desorbed Cs ions followed the tendency in the order SW>GW>NaOAc{approx}MgCl{sub 2}>DW solutions. This indicated that the utilization of extraction reagents for ion exchange will underestimate the Cs desorption behavior. Fitting these experimental data by Langmuir model showed that these extraction reagents have reduced Cs uptake by more than 90%, while only less than 1% of adsorbed Cs ions are still observed in GW and SW solutions in comparison to those in DW. Further SEM/EDS mapping studies clearly demonstrate that these remaining adsorbed Cs ions are at the fracture areas of biotite.

  3. Radioactive cesium in Finnish mushrooms

    International Nuclear Information System (INIS)

    Surveillance of radioactive cesium in Finnish mushrooms was started in 1986 at STUK. Results of the surveillance programs carried out in Lapland and other parts of Finland are given in this report. More than 2000 samples of edible mushrooms have been analysed during 1986-2008. The 137Cs detected in the mushrooms mainly originates from the 137Cs deposition due to the accident at the Chernobyl nuclear power plant in 1986. The 137Cs concentrations of mushrooms in the end of 1970s and in the beginning of 1980s varied from some ten to two hundred becquerels per kilogram originating from the nuclear weapon test period. The uneven division of the Chernobyl fallout is seen in the areal variation of 137Cs concentrations of mushrooms, the 137Cs concentrations being about tenfold in the areas with the highest deposition compared to those where the deposition was lowest. After the Chernobyl accident the maximum values in the 137Cs concentrations were reached during 1987-88 among most species of mushrooms. The 137Cs concentrations have decreased slowly, being in 2008 about 40 per cent of the maximum values. The 137Cs concentrations may be tenfold in the mushroom species with high uptake of cesium (Rozites caperatus, Hygrophorus camarophyllus, Lactarius trivialis) compared to the species with low uptake (Albatrellus ovinus, Leccinum sp.) picked in the same area. The 137Cs contents in certain species of commercial mushrooms in Finland still exceed the maximum permitted level, 600 Bq/kg, recommended to be respected when placing wild game, wild berries, wild mushrooms and lake fish on the market (Commission recommendation 2003/274/Euratom). Therefore, the 137Cs concentrations of mushrooms should be measured before placing them on the market in the areas of the highest 137Cs deposition, except for Albatrellus ovinus, Boletus sp. and Cantharellus cibarius. The 137Cs concentrations of common commercial mushroom species, Cantharellus tubaeformis and Craterellus cornucopioides often

  4. Research on decontamination of cesium contaminated soil by electrokinetic process

    International Nuclear Information System (INIS)

    In this research, electrokinetic process was applied for the decontamination of cesium contaminated soil. As a result, about 4.0 times cesium removal was achieved by applying a DC electric field of 80 V/m to comparing zero electric field in treatment for 30 days. Therefore, the electrokinetic process has a possibility to decontamination of cesium contaminated soil. (author)

  5. Extraction of cesium and barium by dicarbollide and polyethylene glycol in the presence of alkylammonium cations

    International Nuclear Information System (INIS)

    The extraction of cesium and barium cations into nitrobenzene and 60 % (vol.%) nitrobenzene + 40 % CCl4 mixture in the presence of dicarbollide (+Slovafol 909), and primary alkylammonium cations has been studied. Extraction constants determined for three methylammonium cations correlate well with their hydration enthalpies. Reverse order of the hydrophobicity of methylammonium cations (competition with bare Cs+ ion) and for their tendency to enter the polyethylene glycol complex (competition with polyethylene glycol complexed Cs+ and Ba2+ ions) is recorded. The possibility of the regeneration of the organic phase after stripping of Cs+ and Ba2+ ions with methylammonium cations has been investigated. (author) 18 refs.; 7 figs.; 3 tabs

  6. Characterization of cesium uptake mediated by a potassium transport system of bacteria in a soil conditioner

    International Nuclear Information System (INIS)

    We found that bacteria in a commercial soil conditioner sold in Ishinomaki, Miyagi, exhibited concentrative and saturable cesium ion (Cs+) uptake in the natural range of pH and temperature. The concentration of intracellular Cs+ could be condensed at least a few times higher compared with the outside medium of the cells. This uptake appeared to be mediated by a K+ transport system, since Cs+ uptake was dose-dependently inhibited by potassium ion (K+). Eadie-Hofstee plot analysis indicated that the Cs+ uptake involved a single saturable process. The maximum uptake amount (Jmax) was the same in the presence and absence of K+, suggesting that Cs+ and K+ uptakes were competitive with respect to each other. These bacteria might be useful for bioremediation of cesium-contaminated soil. (author)

  7. Microbial accumulation of uranium, radium, and cesium

    International Nuclear Information System (INIS)

    Diverse microbial species varied considerably in their ability to accumulate uranium, cesium, and radium. Mechanistic differences in uranium uptake by Saccharomyces cerevisiae and Pseudomonas aeruginosa were indicated. S. serevisiae exhibited a slow (hours) surface accumulation of uranium which was subject to environmental factors, while P. aeruginosa accumulated uranium rapidly (minutes) as dense intracellular deposits and did not appear to be affected by environmental parameters. Metabolism was not required for uranium uptake by either organism. Cesium and radium were concentrated to a considerably lesser extent than uranium by the several species tested

  8. Environmental transfer of radio-cesium

    International Nuclear Information System (INIS)

    A large amount of Cs 134 and 137 were emitted from the destroyed reactors of Fukushima Daiichi Nuclear Power Station and deposited on the soil surface of vast area including forests, fields, and residential areas. The present report explains mainly land transfer behaviors of cesium which deposited on the surface soils, absorbed into soil particles as time passed on and finally became difficult to move from the particles (aging effect). Depth-distribution of radio-cesium in rice paddy and grassland as well as the change over years is presented. Changes with the passage of time of Cs 137 concentrations in leaves of spinach, wormwood, and persimmon are also provided. (S. Ohno)

  9. Cesium-137 in ash from combustion of biofuels. Application of regulations from the Swedish Radiation Safety Authority; Cesium-137 i aska fraan foerbraenning av biobraenslen. Tillaempning av Straalsaekerhetsmyndighetens regler

    Energy Technology Data Exchange (ETDEWEB)

    Sjoeblom, Rolf (Tekedo AB, Nykoeping (SE))

    2009-03-19

    . The differences are large. The transitions between Cesium/Potassium in the pore water and in the exchangeable positions are rapid. Other transitions are slow. Over the course of a few years, Cesium becomes bonded as non-exchangeable and after a few decades, the content of non-exchangeable and mineral Cesium may be comparable in magnitude. The migration rate depends on the availability. Before Cesium-137 in fallout becomes absorbed, it is transported with the water, and this is the reason for the initial rapid penetration into soil on the order of a decimeter. When most of the Cesium-137 has become non-exchangeable and mineral, the migration rate may be as low as on the order of a millimetre per year. There is an interesting finding to report about clay. For short term migration, i e shortly after a fallout, clay provides a retention that is far superior to that of sand. This is probably related to the fact that clay contains many more positions for ion exchange as compared to sand. After some time when most of the Cesium appears in non-exchangeable and mineral positions, clay and sand are comparable. It might be tempting to assume that organic soils would provide a good retention since they can absorb nutrients from artificial fertilizers and keep them available to plants. Measurements have shown, however, that Cesium-137 may migrate rapidly in soils that lack a mineral component, e g soils consisting of peat. This can be assumed to relate to the fact that the bonding to the many exchangeable positions is much weaker as compared to those in non-exchangeable and in mineral positions. The data on ash are scarce. The data found indicate that the availability of Cesium-137 is high in fresh ash, but that the bonding is remarkably strong already after a few years. It cannot be taken for granted without further information that fresh water conditions apply also when the salt content in the pore water is high. Investigations have shown, however, that the solid mineral phase

  10. A procedure for preferential trapping of cesium cations from aqueous solutions and their separation from other inorganic cations

    International Nuclear Information System (INIS)

    The title procedure is as follows. Deltahedral heteroborane anions are added to the aqueous solution containing cesium ions, precipitate (if any) is separated off, and the cesium salts involving the deltahedral heteroborane anions are trapped on activated carbon. The cobaltocarborane anion [3-Co-(1,2-C2B9H11)2] and/or its substitution derivatives are particularly well suited to this purpose. The process can find use in the separation of radionuclides present in waste solutions arising from spent nuclear fuel treatment. (P.A.). 1 fig

  11. Cesium and Strontium Specific Exchangers for Nuclear Waste Effluent Remediation

    International Nuclear Information System (INIS)

    During the past 50 years, nuclear defense activities have produced large quantities of nuclear waste that now require safe and permanent disposal. The general procedure to be implemented involves the removal of cesium and strontium from the waste solutions for disposal in permanently vitrified media. This requires highly selective sorbents or ion exchangers. Further, at the high radiation doses present in the solution, organic exchangers or sequestrants are likely to decompose over time. Inorganic ion exchangers are resistant to radiation damage and can exhibit remarkably high selectivities. We have synthesized three families of tunnel-type ion exchangers. The crystal structures of these compounds as well as their protonated phases, coupled with ion exchange titrations, were determined and this information was used to develop an understanding of their ion exchange behavior. The ion exchange selectivities of these phases could be regulated by isomorphous replacement of the framework metals by larger or smaller radius metals. In the realm of layered compounds, we prepared alumina, silica, and zirconia pillared clays and sodium micas. The pillared clays yielded very high Kd values for Cs+ and were very effective in removing Cs+ from groundwaters. The sodium micas also had a high affinity for Cs+ but an even greater attraction for S42+. They also possess the property of trapping these ions permanently as the layers slowly decrease their interlayer distance as loading occurs. Sodium nonatitanate exhibited extremely high Kd values for Sr2+ in alkaline tank wastes and should be considered for removal of Sr2+ in such cases. For tank wastes containing complexing agents, we have found that adding Ca2+ to the solution releases the complexed Sr2+ which may then be removed with the CST exchanger

  12. Cesium and Strontium Separation Technologies Literature Review

    Energy Technology Data Exchange (ETDEWEB)

    T. A. Todd; T. A. Todd; J. D. Law; R. S. Herbst

    2004-03-01

    Integral to the Advanced Fuel Cycle Initiative (AFCI) Program’s proposed closed nuclear fuel cycle, the fission products cesium and strontium in the dissolved spent nuclear fuel stream are to be separated and managed separately. A comprehensive literature survey is presented to identify cesium and strontium separation technologies that have the highest potential and to focus research and development efforts on these technologies. Removal of these high-heat-emitting fission products reduces the radiation fields in subsequent fuel cycle reprocessing streams and provides a significant short-term (100 yr) heat source reduction in the repository. This, along with separation of actinides, may provide a substantial future improvement in the amount of fuel that could be stored in a geologic repository. The survey and review of the candidate cesium and strontium separation technologies are presented herein. Because the AFCI program intends to manage cesium and strontium together, technologies that simultaneously separate both elements are of the greatest interest, relative to technologies that separate only one of the two elements.

  13. Scintillator handbook with emphasis on cesium iodide

    Science.gov (United States)

    Tidd, J. L.; Dabbs, J. R.; Levine, N.

    1973-01-01

    This report provides a background of reasonable depth and reference material on scintillators in general. Particular attention is paid to the cesium iodide scintillators as used in the High Energy Astronomy Observatory (HEAO) experiments. It is intended especially for use by persons such as laboratory test personnel who need to obtain a working knowledge of these materials and their characteristics in a short time.

  14. Anomalous wetting of helium on cesium

    International Nuclear Information System (INIS)

    The authors report studies of the anomalous wetting of a cesium substrate by a liquid helium film by means of the technique of third sound. A hysteretic pre-wetting transition is observed as a function of the amount of helium in the experimental cell. 10 refs., 2 figs

  15. Treatment of Soil Decontamination Solution by the Cs+ Ion Selective Ion Exchange Resin

    International Nuclear Information System (INIS)

    Occasionally, radioactively contaminated soils have been excavated and stored at the temporary storage facility. Cesium as a radionuclide is one of the most toxic elements and it has a long half decay life. During the operation of nuclear facility, soils near the facility would be contaminated with radioactive cesium and it will cause the deleterious effect to human body and environment. In this study, Cs+ ion selective ion exchange resin was prepared by changing the functional group of commercial anion exchange resin for a ferrocyanide ion. Ion exchange capability of using the soil decontamination solution was investigated. We also performed the feasibility test of recycling the spent Cs ion selective ion exchange resin

  16. Cesium-137 in ash from combustion of biofuels. Application of regulations from the Swedish Radiation Safety Authority

    International Nuclear Information System (INIS)

    . The differences are large. The transitions between Cesium/Potassium in the pore water and in the exchangeable positions are rapid. Other transitions are slow. Over the course of a few years, Cesium becomes bonded as non-exchangeable and after a few decades, the content of non-exchangeable and mineral Cesium may be comparable in magnitude. The migration rate depends on the availability. Before Cesium-137 in fallout becomes absorbed, it is transported with the water, and this is the reason for the initial rapid penetration into soil on the order of a decimeter. When most of the Cesium-137 has become non-exchangeable and mineral, the migration rate may be as low as on the order of a millimetre per year. There is an interesting finding to report about clay. For short term migration, i e shortly after a fallout, clay provides a retention that is far superior to that of sand. This is probably related to the fact that clay contains many more positions for ion exchange as compared to sand. After some time when most of the Cesium appears in non-exchangeable and mineral positions, clay and sand are comparable. It might be tempting to assume that organic soils would provide a good retention since they can absorb nutrients from artificial fertilizers and keep them available to plants. Measurements have shown, however, that Cesium-137 may migrate rapidly in soils that lack a mineral component, e g soils consisting of peat. This can be assumed to relate to the fact that the bonding to the many exchangeable positions is much weaker as compared to those in non-exchangeable and in mineral positions. The data on ash are scarce. The data found indicate that the availability of Cesium-137 is high in fresh ash, but that the bonding is remarkably strong already after a few years. It cannot be taken for granted without further information that fresh water conditions apply also when the salt content in the pore water is high. Investigations have shown, however, that the solid mineral phase

  17. Electrically switched ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Lilga, M.A. [Pacific Northwest National Lab., Richland, WA (United States); Schwartz, D.T.; Genders, D.

    1997-10-01

    A variety of waste types containing radioactive {sup 137}Cs are found throughout the DOE complex. These waste types include water in reactor cooling basins, radioactive high-level waste (HLW) in underground storage tanks, and groundwater. Safety and regulatory requirements and economics require the removal of radiocesium before these wastes can be permanently disposed of. Electrically Switched Ion Exchange (ESIX) is an approach for radioactive cesium separation that combines IX and electrochemistry to provide a selective, reversible, and economic separation method that also produces little or no secondary waste. In the ESIX process, an electroactive IX film is deposited electrochemically onto a high-surface area electrode, and ion uptake and elution are controlled directly by modulating the potential of the film. For cesium, the electroactive films under investigation are ferrocyanides, which are well known to have high selectivities for cesium in concentrated sodium solutions. When a cathode potential is applied to the film, Fe{sup +3} is reduced to the Fe{sup +2} state, and a cation must be intercalated into the film to maintain charge neutrality (i.e., Cs{sup +} is loaded). Conversely, if an anodic potential is applied, a cation must be released from the film (i.e., Cs{sup +} is unloaded). Therefore, to load the film with cesium, the film is simply reduced; to unload cesium, the film is oxidized.

  18. A new alternative for the decontamination of PWR primary circuits for radioactive cesium and silver by insoluble ferrocyanides

    International Nuclear Information System (INIS)

    The optimal recovery conditions of radioactive cesium and silver from PWR primary circuits were determined on two types of nickel and zinc ferrocyanides. The studied products have been prepared by a slow growth on solid alkaline ferrocyanide particles placed in a concentrated nickel or zinc salt solution. Columns of these products do not react with water or lithium borate solutions as well as with organic solvents. The decontamination factor for cesium or silver is over 1000 for synthetic solutions. The presence of other alkaline ions does not modify these results. In the case of nuclear liquid wastes, the decontamination remains high for cesium. Silver is retained with a good efficiency if it is not under a complex form. This complex is destroyed by acidification. The setting of concrete is not significantly modified by the presence of ferrocyanides. The drawback of this method is a slight elution of some cations composing the ferrocyanides

  19. Cesium and atimony behaviour in water and forest soil after the Chernobyl accident

    International Nuclear Information System (INIS)

    Chemical separation methods have been used to determine the chemical form of 125Sb and 134,137Cs in water and forest soil contaminated by Chernobyl fallout. The water and soil samples were collected within the Gideaa site in the northern part of Sweden between 1986 and 1991. Columns containing cation exchanger, anion exchanger, charcoal and cesium-selective zeolite were used to separate cationic, anionic and uncharged species of 125Sb and 134,137Cs in creek water. The results show that the radioactive cesium and antimony isotopes were present as cations. There are also some indications of 134,137Cs activity (expressed as Bq/kg) bound to particulates as well as uncharged 134,137Cs species. Soil samples collected within the Gideaa site were sieved and the fractions were measured by γ-spectrometry to determine the distribution of the deposited cesium nuclides as a function of the grain size. The results show that 65-90% of 134,137Cs was present in the size fractions with a diameter 125Sb and 134,137Cs were attached to the soil in an ion-exchangeable form, bound to carbonates, organically bound, bound to metal oxides, attached to the outer soil grain surfaces or incorporated into the grain structure. The results show that ∼50% of 137Cs is tightly bound to the grains, while the rest is almost equally distributed between the fractions containing exchangeable ions, carbonates and organic species. The amount of 137Cs available for ion exchange increases with depth, whereas organically bound cesium decreases. Data on 125Sb is sparse, but it indicates that 125Sb is more weakly bound than 137Cs. (orig.)

  20. An isotope dilution-precipitation process for removing radioactive cesium from wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, Harold, E-mail: rogers22@llnl.gov [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, 94550 (United States); Bowers, John; Gates-Anderson, Dianne [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, 94550 (United States)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Developed an isotope dilution-precipitation treatment process for Cs-137 contaminated water. Black-Right-Pointing-Pointer Waste seeded with non-radioactive Cs-133 prior to precipitation with sodium tetraphenylborate. Black-Right-Pointing-Pointer Final Cs-137 concentrations below DOE discharge limit of 3.0 Multiplication-Sign 10{sup -6} {mu}Ci/mL can be achieved. Black-Right-Pointing-Pointer Synthetic wastewater, and industrial low level radioactive proof of principle studies completed. - Abstract: A novel isotope dilution-precipitation method has been developed to remove cesium-137 from radioactive wastewater. The process involves adding stable cesium chloride to wastewater in order to raise the total cesium concentration, which then allows both the stable and radioactive cesium ions to be precipitated together using sodium tetraphenylborate. This process was investigated utilizing laboratory solutions to determine stable cesium dose rates, mixing times, effects of pH, and filtration requirements. Once optimized, the process was then tested on synthetic wastewater and aqueous low-level waste. Experiments showed the reaction to be very quick and stable in the pH range tested, 2.5-11.5. The wastewater may need to be filtered using a 0.45-{mu}m filter, though ferric sulfate has been shown to promote coagulation and settling, thereby eliminating the necessity for filtration. This investigation showed that this isotope dilution-precipitation process can remove Cs-37 levels below the U.S. Department of Energy's (DOE) Derived Concentration Standard (DCS) of 3.0 Multiplication-Sign 10{sup -6} {mu}Ci/mL using a single dosage, potentially allowing the wastewater to be discharged directly to sanitary sewers.

  1. Deployment of Cesium Recovered from High Level Liquid Waste for Irradiation - Indian Scenario - 13128

    Energy Technology Data Exchange (ETDEWEB)

    Vincent, Tessy; Shah, J.G.; Kumar, Amar; Patil, S.B.; Wattal, P.K. [Nuclear Recycle Group, Bhabha Atomic Research Centre, Trombay Mumbai (India)

    2013-07-01

    Recovery of Cs-137 from HLW and its utilisation as source pencil in place of Co-60 is vital for medical and sewage treatment applications in India. For separation of Cs, specific ion exchange resins as well as 'Calyx crown' solvent have been developed and synthesized indigenously. A flow sheet involving separation of Cs from acidic HLW using Ammonium Molybdo Phosphate (AMP) resins, recovery of Cs from the loaded AMP column by dissolving it in alkali, ion exchange purification of Cs rich alkaline solution using Resorcinol-Formaldehyde Poly condensate (RF) resins and its elution in cesium nitrate form was developed and demonstrated. Solvent extraction route employing 0.03 Molar, 1-3-octyl oxy Calyx (4) arene crown-6 in 30% isodecyl alcohol and dodecane was also established using mixer settlers. Cesium lithium borosilicate glass based formulations have been considered as a glass matrix for Cs irradiation pencils. While choosing this vitreous matrix, attributes addressing maximum possible Cs-137 loading, low glass pouring temperature to minimise Cs volatility, reasonably good mechanical strength and good chemical durability have been considered. Recovered cesium nitrate solution was vitrified along with glass additives in an induction heated metallic melter and subsequently poured into 12 numbers of Cs irradiation pencils positioned on turn-table equipped with the load cell. The complete cycle involving recovery of Cs from HLW followed by its conversion into Cs pencil was demonstrated. (authors)

  2. Deployment of Cesium Recovered from High Level Liquid Waste for Irradiation - Indian Scenario - 13128

    International Nuclear Information System (INIS)

    Recovery of Cs-137 from HLW and its utilisation as source pencil in place of Co-60 is vital for medical and sewage treatment applications in India. For separation of Cs, specific ion exchange resins as well as 'Calyx crown' solvent have been developed and synthesized indigenously. A flow sheet involving separation of Cs from acidic HLW using Ammonium Molybdo Phosphate (AMP) resins, recovery of Cs from the loaded AMP column by dissolving it in alkali, ion exchange purification of Cs rich alkaline solution using Resorcinol-Formaldehyde Poly condensate (RF) resins and its elution in cesium nitrate form was developed and demonstrated. Solvent extraction route employing 0.03 Molar, 1-3-octyl oxy Calyx (4) arene crown-6 in 30% isodecyl alcohol and dodecane was also established using mixer settlers. Cesium lithium borosilicate glass based formulations have been considered as a glass matrix for Cs irradiation pencils. While choosing this vitreous matrix, attributes addressing maximum possible Cs-137 loading, low glass pouring temperature to minimise Cs volatility, reasonably good mechanical strength and good chemical durability have been considered. Recovered cesium nitrate solution was vitrified along with glass additives in an induction heated metallic melter and subsequently poured into 12 numbers of Cs irradiation pencils positioned on turn-table equipped with the load cell. The complete cycle involving recovery of Cs from HLW followed by its conversion into Cs pencil was demonstrated. (authors)

  3. Fire Safety Tests for Cesium-Loaded Spherical Resorcinol Formaldehyde Resin: Data Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong-Sang; Schweiger, Michael J.; Peterson, Reid A.

    2012-09-01

    A draft safety evaluation of the scenario for spherical resorcinol formaldehyde (SRF) resin fire inside the ion exchange column was performed by the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Fire Safety organization. The result of this draft evaluation suggested a potential change of the fire safety classification for the Cesium Ion Exchange Process System (CXP) emergency elution vessels, equipment, and piping. To resolve this question, the fire properties of the SRF resin were measured by Southwest Research Institute (SwRI) through a subcontract managed by Pacific Northwest National Laboratory (PNNL). The results of initial fire safety tests on the SRF resin were documented in a previous report (WTP-RPT-218). The present report summarizes the results of additional tests performed by SwRI on the cesium-loaded SRF resin. The efforts by PNNL were limited to summarizing the test results provided by SwRI into one consolidated data report. The as-received SwRI report is attached to this report in the Appendix A. Where applicable, the precision and bias of each test method, as given by each American Society for Testing and Materials (ASTM) standard procedure, are included and compared with the SwRI test results of the cesium-loaded SRF resin.

  4. Hot tungsten plate based ionizer for cesium plasma in a multi-cusp field experiment

    International Nuclear Information System (INIS)

    In a newly proposed basic experiment, contact-ionized cesium ions will be confined by a multi cups magnetic field configuration. The cesium ion will be produced by impinging collimated neutral atoms on an ionizer consisting of the hot tungsten plate. The temperature of the tungsten plate will also be made high enough (∼2700 K) such that it will contribute electrons also to the plasma. It is expected that at this configuration the cesium plasma would be really quiescent and would be free from even the normal drift waves observed in the classical Q-machines. For the ionizer a design based on F. F. Chen's design was made. This ionizer is very fine machining and exotic material like Tungsten plate, Molybdenum screws, rings, and Boron Nitride ceramics etc. The fine and careful machining of these materials was very hard. In this paper, the experience about to join the tungsten wire to molybdenum plate and alloy of tantalum and molybdenum ring is described. In addition experimental investigations have been made to measure 2D temperature distribution profile of the Tungsten hot plate using infrared camera and the uniformity of temperature distribution over the hot plate surface is discussed. (author)

  5. Static and dynamic experiments for the retention of cesium in nitrate containing, nitric acid solutions

    International Nuclear Information System (INIS)

    The separation of cesium from medium active waste (MAW) of the Purex-Process by chromatographic methods is demonstrated using the inorganic ion exchanger ammoniummolybdatophosphate (AMP-1). Other inorganic exchangers like ammoniumhexacyanocobaltousferrate (NCFC), zirkoniumphosphate (ZPH) and antimonypentoxid (HAP) have shown for different pH-values a reasonable retention for cesium (NCFC (pH 12) : 35 g Cs/kgNCFC, ZPH(pH 7) : 100 g Cs/kgZPH and HAP (pH 2) : 55 g Cs/kgHAP). But with a high salt loading (300 g/l NaNO3) a loss of capacities occurs which does not allow the use of these exchangers, whereas AMP-1 is useful from a pH of 9 to conc. HNO3 with this high salt loadings with a capacity of 60 g Cs/kg AMP-1. (orig.)

  6. Spin-injection optical pumping of molten cesium salt and its NMR diagnosis

    International Nuclear Information System (INIS)

    Nuclear spin polarization of cesium ions in the salt was enhanced during optical pumping of cesium vapor at high magnetic field. Significant motional narrowing and frequency shift of NMR signals were observed by intense laser heating of the salt. When the hyperpolarized salt was cooled by blocking the heating laser, the signal width and frequency changed during cooling and presented the phase transition from liquid to solid. Hence, we find that the signal enhancement is mostly due to the molten salt and nuclear spin polarization is injected into the salt efficiently in the liquid phase. We also show that optical pumping similarly induces line narrowing in the solid phase. The use of powdered salt provided an increase in effective surface area and signal amplitude without glass wool in the glass cells

  7. Strontium-90 and cesium-137 in milk

    International Nuclear Information System (INIS)

    The milk samples have been collected from 30 prefectures by prefectural public health laboratories and institutes (raw milk: 4 times per year for the report to WHO, and raw and city milk: 2 times per year), and analysed for strontium-90 and cesium-137 content at Japan Chemical Analysis Center. Collected samples were the raw milk and the city ones for the producing districts and the consuming ones, respectively. Three liters of fresh milk were carbonized in each prefectural public health laboratories and institutes, and then it was asked at Japan Chemical Analysis Center. The ask to which both some carriers and hydrochloric acid were added, was destroyed under heating. The nuclides was dissolved into hydrochloric acid and filtrated, after it was added with nitric acid and heated to dryness. The filtrate was radiochemically analysed for strontium-90 and cesium-137 using the method recommended by Science and Technology Agency. (author)

  8. Cesium stress and adaptation in pseudomonas fluorescens

    International Nuclear Information System (INIS)

    Industrialization and acid rain have led to a marked increment on the bioavailability of numerous metals. These metallic pollutants pose a serious threat to the ecosystem due to their ability to interact negatively with living organisms. Thus, considerable effort has been directed towards the development of environmentally-friendly technologies tailored to the management of metal wastes. As microbes are known to adapt to most environmental stresses, they constitute organisms of choice in the study of molecular adaptation processes. The adaptive features may be subsequently engineered for biotechnological applications. Cesium, a monovalent metal with chemical similarities to potassium but no know essential biological function has become a cause of environmental concern owing to its accidental release from the Chernobyl nuclear accident. This study examines the impact of cesium on the soil microbe Pseudomonas fluorescensts, and discusses the possibilities of its use in management of this nuclear waste. 15 refs., 3 figs

  9. Thermochemical evaluation and preparation of cesium uranates

    International Nuclear Information System (INIS)

    Two kinds of cesium uranates, Cs2UO4 and Cs2U2O7, which are predicted by thermochemical estimation to be formed in irradiated oxide fuels, were prepared from U3O8 and Cs2CO3 for measurements of the thermal expansions and thermal conductivities. In advance of the preparation, thermochemical calculations for the formation and decomposition of these cesium uranates were performed by Gibbs free energy minimizer. The preparation temperatures for Cs2UO4 and Cs2U2O7 were determined from the results of the thermochemical calculations. The prepared samples were analyzed by X-ray diffraction, which showed that the single phases of Cs2UO4 and Cs2U2O7 were formed. Thermogravimetry and differential thermal analysis were also performed on these samples, and the decomposition temperatures were evaluated. The experimental results were in good agreement with those of the thermochemical calculations. (author)

  10. Evaluation and comparison of SuperLig reg-sign 644, resorcinol-formaldehyde and CS-100 ion exchange materials for the removal of cesium from simulated alkaline supernate

    International Nuclear Information System (INIS)

    PNL evaluated three polymeric materials for Cs removal efficiency from a simulated Hanford Neutralized Current Acid Waste (NCAW) supernatant liquid using 200 mL ion exchange columns. Cs loadings (mmole Cs/g resin) were 0.20, 0.18, and 0.039 for Super Lig 644, R-F, and CS-100 (0.045, 0.070, 0.011 mmole Cs/mL resin). Elution of each resin material with 0.5 M HNO3 required 3.5, 7.0, and 3.2 cv to reach 0.1 C/C0 for the respective materials, resulting in volume compressions of 27, 20, and 6.9. Peak Cs concentrations during elution was 185, 38.5, and 27.8 C/C0. SuperLig 644 had the highest Cs loading per gram in NCAW and the greatest volume compression on aci elution. Because of high density and poor elution, R-F had the highest Cs loading per unit volume and lower volume compression. CS-100, the baseline material for Cs removal at Hanford, was inferior to both SuperLig 644 and R-F in terms of Cs loading and selectivity over sodium

  11. Efficient cesiation in RF driven surface plasma negative ion source

    Energy Technology Data Exchange (ETDEWEB)

    Belchenko, Yu.; Ivanov, A.; Konstantinov, S.; Sanin, A., E-mail: sanin@inp.nsk.su; Sotnikov, O. [Budker Institute of Nuclear Physics, Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2016-02-15

    Experiments on hydrogen negative ions production in the large radio-frequency negative ion source with cesium seed are described. The system of directed cesium deposition to the plasma grid periphery was used. The small cesium seed (∼0.5 G) provides an enhanced H{sup −} production during a 2 month long experimental cycle. The gradual increase of negative ion yield during the long-term source runs was observed after cesium addition to the source. The degraded H{sup −} production was recorded after air filling to the source or after the cesium washing away from the driver and plasma chamber walls. The following source conditioning by beam shots produces the gradual recovery of H{sup −} yield to the high value. The effect of H{sup −} yield recovery after cesium coverage passivation by air fill was studied. The concept of cesium coverage replenishment and of H{sup −} yield recovery due to sputtering of cesium from the deteriorated layers is discussed.

  12. Cesium legacy safety project management work plan

    International Nuclear Information System (INIS)

    This Management Work Plan (MWP) describes the process flow, quality assurance controls, and the Environment, Safety, and Health requirements of the Cesium Legacy Safety Project. This MWP provides an overview of the project goals and methods for repackaging the non-conforming Type W overpacks and packaging the CsCl powder and pellets. This MWP is not intended to apply to other activities associated with the CsCl Legacy Safety Program (i.e., clean out of South Cell)

  13. Murine immunization by cesium-137 irradiation attenuated Schistosoma mansoni cercariae

    International Nuclear Information System (INIS)

    Cesium-137, becoming a more readily available ionizing gamma radiation source for laboratory use, was shown to effectively attenuate Schistosoma mansoni cercariae for vaccine production. In parallel comparison studies with the murine model, cesium-137 attenuated cercariae consistently afforded better protection than did the cobalt-60 prepared vaccine. Dose-response data indicated that the optimal total irradiation with cesium-137 was between 45 and 50 Krad

  14. Murine immunization by cesium-137 irradiation attenuated Schistosoma mansoni cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Stek, M. Jr.; Minard, P.; Cruess, D.F.

    1984-06-01

    Cesium-137, becoming a more readily available ionizing gamma radiation source for laboratory use, was shown to effectively attenuate Schistosoma mansoni cercariae for vaccine production. In parallel comparison studies with the murine model, cesium-137 attenuated cercariae consistently afforded better protection than did the cobalt-60 prepared vaccine. Dose-response data indicated that the optimal total irradiation with cesium-137 was between 45 and 50 Krad.

  15. Sorption of cesium 137 by steel from sodium melt

    International Nuclear Information System (INIS)

    Sorption of cesium-137 radionuclide by Kh18N10T steel from sodium melt at different temperatures (150-450 deg C) has been studied. Equilibrium coefficients of cesium distribution between sodium and steel are determined, which depend on the conditions of sorption realization, such as cesium concentration in sodium melt, the content of oxygen admixture in sodium and the state of sorbing surface

  16. MALT accelerator facility; characteristic of ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Chuichiro; Kobayashi, Koichi; Matsuzaki, Hiroyuki; Sunohara, Yoko [Tokyo Univ. (Japan)

    2001-02-01

    A tandem accelerator has been operated since 1995 with a continual effort to increase the accuracy and reliability of the measurement. In the present paper, after a brief discussion on a cesium sputter ion source incorporated in the MALT accelerator, basic characteristics such as temperature of cesium reservoir, and ioniser plate cathode potential. Production of negative ions in the ion source proceed in two step. The first step is generation of positive ions due to the surface ionization on a hot Ta plate, and the second step, electron detachment on a cathode. (M. Tanaka)

  17. Cesium-137 as a radiation source

    International Nuclear Information System (INIS)

    The U.S. Department of Energy (DOE) Byproducts Utilization Program (BUP) seeks to develop and encourage widespread commercial use of defense byproducts that are produced by DOE. Cesium-l37 is one such byproduct that is radioactive and decays with emission of gamma rays. The beneficial use of this radiation to disinfect sewage sludge or disinfest food commodities is actively being pursued by the program. The radiation produced by cesium-l37(Cs-l37) is identical in form to that produced by cobalt-60(Co-60), an isotope that is widely used in commercial applications such as medical product sterilization. The choice of isotope to use depends on several factors ranging from inherent properties of the isotopes to availability and cost. The BUP, although centrally concerned with the beneficial use of Cs-l37, by investigating and assessing the feasibility of various uses hopes to define appropriate circumstances where cesium or cobalt might best be used to accomplish specific objectives. This paper discusses some of the factors that should be considered when evaluating potential uses for isotopic sources

  18. Removal of cesium from red deer meat

    International Nuclear Information System (INIS)

    The effect was studied of marinading on the reduction of cesium radionuclide activity in red deer meat contaminated by ingestion of feed containing 134Cs+137Cs from radioactive fallout following the Chernobyl accident. Two types of marinade were studied, viz., a vinegar infusion and a vinegar infusion with an addition of vegetables and spices. The meat was chopped to cubes of about 1.5 cm in size and the marinading process took place at temperatures of 5 and 11 degC. The drop of cesium content in the meat was determined by gamma spectrometry at given time intervals. The replacement of the marinade and the duration of the process were found to maximally affect efficiency. If the solution was not replaced, about 80% of cesium radionuclides were removed after seven hours of marinading. With one replacement of the infusion the drop in 134Cs+137Cs radioactivity amounted to up to 90% after seven hours of marinading. No effects were shown of vegetable additions to the vinegar infusion and of the change in temperature from 5 to 11 degC on the efficiency of the process. (author). 3 tabs., 6 refs

  19. Surface interactions of cesium and boric acid with stainless steel

    International Nuclear Information System (INIS)

    In this report, the effects of cesium hydroxide and boric acid on oxidized stainless steel surfaces at high temperatures and near one atmosphere of pressure are investigated. This is the first experimental investigation of this chemical system. The experimental investigations were performed using a mass spectrometer and a mass electrobalance. Surfaces from the different experiments were examined using a scanning electron microscope to identify the presence of deposited species, and electron spectroscopy for chemical analysis to identify the species deposited on the surface. A better understanding of the equilibrium thermodynamics, the kinetics of the steam-accelerated volatilizations, and the release kinetics are gained by these experiments. The release rate is characterized by bulk vaporization/gas-phase mass transfer data. The analysis couples vaporization, deposition, and desorption of the compounds formed by cesium hydroxide and boric acid under conditions similar to what is expected during certain nuclear reactor accidents. This study shows that cesium deposits on an oxidized stainless steel surface at temperatures between 1000 and 1200 Kelvin. Cesium also deposits on stainless steel surfaces coated with boric oxide in the same temperature ranges. The mechanism for cesium deposition onto the oxide layer was found to involve the chemical reaction between cesium and chromate. Some revaporization in the cesium hydroxide-boric acid system was observed. It has been found that under the conditions given, boric acid will react with cesium hydroxide to form cesium metaborate. A model is proposed for this chemical reaction

  20. Distribution and retention of cesium in Swedish boreal forest ecosystems

    International Nuclear Information System (INIS)

    The retention and distribution of cesium in forest environments are being studied at three locations in Sweden. The main part of the cesium found in the soil was recovered in horizons rich in organic matter. The cesium was retained in the soil organic matter in a more or less extractable form. As different soil types have a different distribution pattern of organic matter the distribution of cesium will depend on the forest soil type. The clay content in Swedish forest soils is in general low which will mitigate the retention of cesium in the soil mineral horizons. The cesium present in the tree was considered to be an effect of assimilation by the tissues in the canopy as well as by the roots. The redistribution of cesium within the trees was extensive which was considered to be an effect of a high mobility of cesium in the close system of a forest environment. The cesium will remain in the forest environment for a considerable time but can be removed by forest practice, by leaching out of the soil profile or by the radioactive decay. (au)

  1. Lanthanide doped strontium-barium cesium halide scintillators

    Science.gov (United States)

    Bizarri, Gregory; Bourret-Courchesne, Edith; Derenzo, Stephen E.; Borade, Ramesh B.; Gundiah, Gautam; Yan, Zewu; Hanrahan, Stephen M.; Chaudhry, Anurag; Canning, Andrew

    2015-06-09

    The present invention provides for a composition comprising an inorganic scintillator comprising an optionally lanthanide-doped strontium-barium, optionally cesium, halide, useful for detecting nuclear material.

  2. Unstable Electrostatic Ion Cyclotron Waves Exited by an Ion Beam

    DEFF Research Database (Denmark)

    Michelsen, Poul; Pécseli, Hans; Juul Rasmussen, Jens;

    1976-01-01

    Electrostatic ion cyclotron waves were observed in a quiescent cesium plasma into which a low‐energy beam of sodium ions was injected. The instability appeared when the beam velocity was above 12 times the ion thermal velocity. The waves propagated along the magnetic field with a velocity somewha...... smaller than that of the beam. The dispersion relation was in good agreement with theory.......Electrostatic ion cyclotron waves were observed in a quiescent cesium plasma into which a low‐energy beam of sodium ions was injected. The instability appeared when the beam velocity was above 12 times the ion thermal velocity. The waves propagated along the magnetic field with a velocity somewhat...

  3. Latex particles functionalized with transition metals ferrocyanides for cesium uptake and decontamination of solid bulk materials

    International Nuclear Information System (INIS)

    Decontamination of spent ion-exchange resins, corrosion-unstable metal structures, soil, ground, and construction materials contaminated by fission, corrosion and transuranic radionuclides remains one of the most urgent and complicated ecological problems. Among the existing methods having different efficiencies in regard to such materials decontamination, application of selective sorbents put into a humid medium to be decontaminated (ground, bulk materials) appears to be rather extensive. However, the efficiency of such an approach is significantly limited by difficulties concerned with uniform sorbent distribution in porous media and completeness of spent sorbents removal for final disposal. In this paper we suggest a principally new approach to preparation of colloid-stable selective sorbents for cesium uptake using immobilization of transition metals (cobalt, nickel, and copper) ferrocyanides in nanosized carboxylic latex emulsions. The effects of ferrocyanide composition, pH, and media salinity on the sorption properties of the colloid-stable sorbents toward cesium ions were studied in solutions containing up to 200 g/1 sodium nitrate or potassium chloride. The sorption capacities of the colloid sorbents based on mixed potassium/transition metals ferrocyanides were in the range 1.45-1.86 mol Cs/mol ferrocyanide with the highest value found for the copper ferrocyanide. It was shown that the obtained colloid-stable sorbents were capable to penetrate through bulk materials without filtration that makes them applicable for decontamination of solids, e.g. soils, zeolites, spent ion-exchange resins contaminated with cesium radionuclides. After decontamination of liquid or solid radioactive wastes the colloid-stable sorbents can be easily separated from solutions by precipitation with cationic flocculants providing localization of radionuclides in a small volume of the precipitates formed. Besides, functionalized latex particles can be used for preparation of carbon

  4. Cesium Isotherm Testing with Spherical Resorcinol-Formaldehyde Resin at High Sodium Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Renee L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fiskum, Sandra K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smoot, Margaret R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rinehart, Donald E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-04-01

    Washington River Protection Solutions (WRPS) is developing a Low-Activity Waste Pretreatment System (LAWPS) to provide low-activity waste (LAW) directly to the Hanford Tank Waste Treatment and Immobilization Plant (WTP) Low-Activity Waste Facility for immobilization. The pretreatment that will be conducted on tank waste supernate at the LAWPS facility entails filtration to remove entrained solids and cesium (Cs) ion exchange to remove Cs from the product sent to the WTP. Currently, spherical resorcinol-formaldehyde (sRF) resin (Microbeads AS, Skedsmokorset, Norway) is the Cs ion exchange resin of choice. Most work on Cs ion exchange efficacy in Hanford tank waste has been conducted at nominally 5 M sodium (Na). WRPS is examining the possibility of processing supernatant at high Na concentrations—up to 8 M Na—to maximize processing efficiency through the LAWPS. Minimal Cs ion exchange work has been conducted at 6 M and 8 M Na concentrations..

  5. Fabrication of stimuli-sensitive hydrogel for the removal of cesium

    International Nuclear Information System (INIS)

    The nuclear accident at the Fukushima Daiichi nuclear power station in 2011 released a huge quantity of radioactive contaminants into the environment.1 Among these, cesium Cs-137 is the most problematic contaminant due to its long half-life (30.2 years), and high-energy gamma ray (γ-ray) emissions. 2 Various surface including road, roof, house, building were contaminated with Cs-137. These coating materials have some problems and limitation such as toxic component, and lack of reusability of materials related to the cost. Thus, a more cost-effective and environmental friendly coating materials is still desired. 3 In the present study, the stimuli-sensitive hydrogel were fabricated for the removal of radioactive Cs from solid surface. We describe the morphology, structure, and physical property of these stimuli sensitive hydrogel. In addition, their ability to eliminate cesium was also evaluated. The smart hydrogel coating materials showed an excellent morphology change from the liquid to film by addition of Ca ion. Therefore, the stimuli-sensitive hydrogel demonstrated good potential for the treatment of contaminated surface for the removal of radioactive cesium

  6. Zirconium phosphate waste forms for low-temperature stabilization of cesium-137-containing waste streams

    International Nuclear Information System (INIS)

    Novel chemically bonded phosphate ceramics are being developed and fabricated for low-temperature stabilization and solidification of waste streams that are not amenable to conventional high-temperature stabilization processes because volatiles are present in the wastes. A composite of zirconium-magnesium phosphate has been developed and shown to stabilize ash waste contaminated with a radioactive surrogate of 137Cs. Excellent retainment of cesium in the phosphate matrix system was observed in Toxicity Characteristic Leaching Procedure tests. This was attributed to the capture of cesium in the layered zirconium phosphate structure by intercalation ion-exchange reaction. But because zirconium phosphate has low strength, a novel zirconium/magnesium phosphate composite waste form system was developed. The performance of these final waste forms, as indicated by compression strength and durability in aqueous environments, satisfy the regulatory criteria. Test results indicate that zirconium-magnesium-phosphate-based final waste forms present a viable technology for treatment and solidification of cesium-contaminated wastes

  7. Fabrication of stimuli-sensitive hydrogel for the removal of cesium

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hee-Man; Bong, Sang Bum; Park, Chan Woo; Lee, Kune Woo; Seo, Bum-Kyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    The nuclear accident at the Fukushima Daiichi nuclear power station in 2011 released a huge quantity of radioactive contaminants into the environment.1 Among these, cesium Cs-137 is the most problematic contaminant due to its long half-life (30.2 years), and high-energy gamma ray (γ-ray) emissions. 2 Various surface including road, roof, house, building were contaminated with Cs-137. These coating materials have some problems and limitation such as toxic component, and lack of reusability of materials related to the cost. Thus, a more cost-effective and environmental friendly coating materials is still desired. 3 In the present study, the stimuli-sensitive hydrogel were fabricated for the removal of radioactive Cs from solid surface. We describe the morphology, structure, and physical property of these stimuli sensitive hydrogel. In addition, their ability to eliminate cesium was also evaluated. The smart hydrogel coating materials showed an excellent morphology change from the liquid to film by addition of Ca ion. Therefore, the stimuli-sensitive hydrogel demonstrated good potential for the treatment of contaminated surface for the removal of radioactive cesium.

  8. Distillation device supplies cesium vapor at constant pressure

    Science.gov (United States)

    Basiulis, A.; Shefsiek, P. K.

    1968-01-01

    Distillation apparatus in the form of a U tube supplies small amounts of pure cesium vapor at constant pressure to a thermionic converter. The upstream leg of the U tube is connected to a vacuum pump to withdraw noncondensable impurities, the bottom portion serves as a reservoir for the liquid cesium.

  9. Cesium-137 in grass from Chernobyl fallout

    International Nuclear Information System (INIS)

    Grass ecosystem was monitored for 137Cs, a relatively long-lived radionuclide, for about 16 years since the Chernobyl reactor accident occurred on April 26, 1986. Cesium-137 in grass gramineae or poaceae the species, ranged from 122.9 Bq kg-1 (September 4, 1986) to 5.8 mBq kg-1 (October 16, 2001) that is a range of five orders of magnitude. It was observed that there was a trend of decreasing 137Cs with time reflecting a removal half-time of 40 months (3 1/3 years), which is the ecological half-life, T ec of 137Cs in grassland

  10. Plutonium and Cesium Colloid Mediated Transport

    Science.gov (United States)

    Boukhalfa, H.; Dittrich, T.; Reimus, P. W.; Ware, D.; Erdmann, B.; Wasserman, N. L.; Abdel-Fattah, A. I.

    2013-12-01

    Plutonium and cesium have been released to the environment at many different locations worldwide and are present in spent fuel at significant levels. Accurate understanding of the mechanisms that control their fate and transport in the environment is important for the management of contaminated sites, for forensic applications, and for the development of robust repositories for the disposal of spent nuclear fuel and nuclear waste. Plutonium, which can be present in the environment in multiple oxidations states and various chemical forms including amorphous oxy(hydr)oxide phases, adsorbs/adheres very strongly to geological materials and is usually immobile in all its chemical forms. However, when associated with natural colloids, it has the potential to migrate significant distances from its point of release. Like plutonium, cesium is not very mobile and tends to remain adhered to geological materials near its release point, although its transport can be enhanced by natural colloids. However, the reactivity of plutonium and cesium are very different, so their colloid-mediated transport might be significantly different in subsurface environments. In this study, we performed controlled experiments in two identically-prepared columns; one dedicated to Pu and natural colloid transport experiments, and the other to Cs and colloid experiments. Multiple flow-through experiments were conducted in each column, with the effluent solutions being collected and re-injected into the same column two times to examine the persistence and scaling behavior of the natural colloids, Pu and Cs. The data show that that a significant fraction of colloids were retained in the first elution through each column, but the eluted colloids collected from the first run transported almost conservatively in subsequent runs. Plutonium transport tracked natural colloids in the first run but deviated from the transport of natural colloids in the second and third runs. Cesium transport tracked natural

  11. Extraction of radioactive cesium from ash of flammable radioactive material

    International Nuclear Information System (INIS)

    Huge amount of radioactive materials was released by the hydrogen explosion at Fukushima Daiichi Nuclear Power Plant due to the Great East Japan Earthquake on March 11, 2011. Suppression of the volume of radioactive materials stored by decontamination works is strongly required since the preparation of storage places is not easy. We are developing the technology for separation and concentration of radioactive cesium using nano-particle, Prussian blue, as a cesium adsorption material which has a high efficiency and good selectivity. We propose a method in which radioactive cesium is extracted from the ash of flammable materials into the water and the Prussian blue nano-particles are added to the water to collect cesium. The volume of radioactive wastes contaminated by cesium is expected to be cut down with these processes. (J.P.N.)

  12. A combined cesium-strontium extraction/recovery process

    International Nuclear Information System (INIS)

    A new solvent extraction process for the simultaneous extraction of cesium and strontium from acidic nitrate media is described. This process uses a solvent formulation comprised of 0.05 M di-t-butylcyclohexano-18-crown-6 (DtBuCH18C6), 0.1 M Crown 100' (a proprietary, cesium-selective derivative of dibenzo-18-crown-6), 1.2 M tributyl phosphate (TBP), and 5% (v/v) lauryl nitrile in an isoparaffinic hydrocarbon diluent. Distribution ratios for cesium and strontium from 4 M nitric acid are 4.13 and 3.46, respectively. A benchtop batch countercurrent extraction experiment indicates that >98% of the cesium and strontium initially present in the feed solution can be removed in only four extraction stages. Through proper choice of extraction and strip conditions, extracted cesium and strontium can be recovered either together or individually

  13. Steady-state operation of an ampere-class hydrogen negative ion source

    International Nuclear Information System (INIS)

    A cesium-seeded volume negative ion source producing H- ion beams of 800 mA has been operated continuously at a high current density of 20 mA/cm2. The negative ion yield is enhanced by more than a factor of four by injecting 600 mg of cesium and keeping the plasma grid temperature at 250-300degC. After a continuous operation for 140 hours, cesium distribution along the beam line was measured by ICP mass spectroscopy. It turned out that about 90% of the injected cesium was left in the plasma generator and the consumption rate of the cesium is as low as 3 mg/hour at a room temperature. (author)

  14. Studies on release and deposition behaviour of cesium from contaminated sodium pools and cesium trap development for FBTR

    International Nuclear Information System (INIS)

    Investigations were carried out on the release and deposition behaviour of cesium from sodium pools in air-filled chamber in the temperature range of 673 to 873 K, using Cs-134 to simulate Cs-137. About 0.12 kg of sodium was loaded in a burn-pot together with 92.5 kBq of cesium. Experiments were carried out with 21% oxygen. Natural burning period of sodium and specific activity ratio between cesium and sodium showed a tendency to decrease and release fractions of both the species tended to increase with temperature. From the surface deposited aerosols it was observed that cesium has propensity to settle down closer to the point of release. A cesium trap has been developed for FBTR with RVC as getter material. Absorption kinetics and particle release behaviour studies pointed to its intended satisfactory performance in the plant. (author)

  15. Sympathetic cooling in a rubidium cesium mixture: Production of ultracold cesium atoms

    International Nuclear Information System (INIS)

    This thesis presents experiments for the production of ultracold rubidium cesium mixture in a magnetic trap. The long-termed aim of the experiment is the study of the interaction of few cesium atoms with a Bose-Einstein condensate of rubidium atoms. Especially by controlled variation of the cesium atom number the transition in the description of the interaction by concepts of the one-particle physics to the description by concepts of the many-particle physics shall be studied. The rubidium atoms are trapped in a magneto-optical trap (MOT) and from there reloaded into a magnetic trap. In this the rubidium atoms are stored in the state vertical stroke f=2,mf=2 right angle of the electronic ground state and evaporatively cooled by means of microwave-induced transitions into the state vertical stroke f=1,mf=1] (microwave cooling). The cesium atoms are also trppaed in a MOT and into the same magnetic trap reloaded, in which they are stored in the state vertical stroke f=4,mf=4 right angle of the electronic ground state together with rubidium. Because of the different hyperfine splitting only rubidium is evaporatively cooled, while cesium is cooled jointly sympathetically - i.e. by theramal contact via elastic collisions with rubidium atoms. The first two chapters contain a description of interatomic interactions in ultracold gases as well as a short summary of theoretical concepts in the description of Bose-Einstein condensates. The chapters 3 and 4 contain a short presentation of the methods applied in the experiment for the production of ultracold gases as well as the experimental arrangement; especially in the framework of this thesis a new coil system has been designed, which offers in view of future experiments additionally optical access for an optical trap. Additionally the fourth chapter contains an extensive description of the experimental cycle, which is applied in order to store rubidium and cesium atoms together into the magnetic trap. The last chapter

  16. Microbial uptake of uranium, cesium, and radium

    International Nuclear Information System (INIS)

    The ability of diverse microbial species to concentrate uranium, cesium, and radium was examined. Saccharomyces cerevisiae, Pseudomonas aeruginosa, and a mixed culture of denitrifying bacteria accumulated uranium to 10 to 15% of the dry cell weight. Only a fraction of the cells in a given population had visible uranium deposits in electron micrographs. While metabolism was not required for uranium uptake, mechanistic differences in the metal uptake process were indicated. Uranium accumulated slowly (hours) on the surface of S. cerevisiae and was subject to environmental factors (i.e., temperature, pH, interfering cations and anions). In contrast, P. aeruginosa and the mixed culture of denitrifying bacteria accumulated uranium rapidly (minutes) as dense, apparently random, intracellular deposits. This very rapid accumulation has prevented us from determining whether the uptake rate during the transient between the initial and equilibrium distribution of uranium is affected by environmental conditions. However, the final equilibrium distributions are not affected by those conditions which affect uptake by S. cerevisiae. Cesium and radium were concentrated to a considerably lesser extent than uranium by the several microbial species tested. The potential utility of microorganisms for the removal and concentration of these metals from nuclear processing wastes and several bioreactor designs for contacting microorganisms with contaminated waste streams will be discussed

  17. Electrochemical assessment of water|ionic liquid biphasic systems towards cesium extraction from nuclear waste

    OpenAIRE

    Stockmann, T. Jane; Zhang, Jing; Montgomery, Anne-Marie; Ding, Zhifeng

    2014-01-01

    A room temperature ionic liquid (IL) composed of a quaternary alkylphosphonium (trihexyltetradecylphosphonium, P66614(+)) and tetrakis(pentafluorophenyl) borate anion (TB) was employed within a water| P66614TB (w|P66614TB or w|IL) biphasic system to evaluate cesium ion extraction in comparison to that with a traditional water|organic solvent (w|o) combination. Cs-137 is a major contributor to the radioactivity of spent nuclear fuel as it leaves the reactor, and its extraction efficiency is th...

  18. Observation of X-ray-induced phase transition phenomenon of cesium manganese hexacyanoferrate

    Energy Technology Data Exchange (ETDEWEB)

    Ishiji, K [Kyushu Synchrotron Light Research Center, 8-7 Yayoigaoka, Tosu, Saga 841-0005 (Japan); Deguchi, M; Nakajima, N [Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Matsuda, T; Tokoro, H; Ohkoshi, S [Department of Chemistry, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Iwazumi, T, E-mail: ishiji@saga-ls.j [Department of Mathematical Sciences, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531 (Japan)

    2009-02-01

    Cesium manganese hexacyanoferrate is an interesting material which exhibits the phase transition with the magnetic susceptibility variation under the effect of external stimuli; such as temperature and visible light irradiation. This phase transition attributes the charge transfer between ions in the Fe-CN-Mn bond. Recently, we observed the phase transition by X-ray irradiation below 80 K. The X-ray absorption spectrum of the low-temperature (LT) phase approached toward that of the high-temperature (HT) phase. The spectrum variation by X-ray irradiation attributes the charge transfer from Fe{sup II} to Mn{sup III}.

  19. Ion-exchange behavior of alkali metals on treated carbons

    International Nuclear Information System (INIS)

    The ion-exchange behavior of trace quantities of the alkali-metal ions sodium and cesium, on activated carbon impregnated with zirconium phosphate (referred to here as ZrP), was studied. Impregnated carbon had twice as much ion-exchange activity as unimpregnated, oxidized carbon, and 10 times as much as commercial activated carbons. The distribution coefficient of sodium increased with increasing pH; the distribution coefficient of cesium decreased with increasing pH. Sodium and cesium were separated with an electrolytic solution of 0.1 M HCl. Preliminary studies indicated that 0.2 M potassium and cesium can also be separated. Distribution coefficients of the supported ZrP were determined by the elution technique and agreed within 20% of the values for pure ZrP calculated from the literature

  20. Study of the removal of cesium from aqueous solutions by graphene oxide; Estudo da remocao de cesio em solucoes aquosas por oxido de grafeno

    Energy Technology Data Exchange (ETDEWEB)

    Bueno, Vanessa N.; Rodrigues, Debora F. [University of Houston (UH), Houston, TX (United States); Vitta, Patricia B. Di [Universidade de Sao Paulo (STRES/USP), Sao Paulo, SP (Brazil). Inst. de Quimica. Setor Tecnico de Residuos Quimicos e Solventes; Oshiro, Mauricio T.; Vicente, Roberto; Hiromoto, Goro; Potiens Junior, Ademar; Sakata, Solange K., E-mail: sksakata@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Graphene oxide, used in this work, was synthesized from the oxidation of graphite by Hummer method. The experiments were performed in batch and analyzed for the following parameters: contact time, pH, cesium ion concentration in aqueous solution and removing capacity of the graphene oxide. After the experiments the samples were vacuum filtered and the remaining cesium in solution was quantified by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). The equilibrium was reached after 60 minutes of contact in neutral solution. The percentage of removal was around 80%.

  1. Separating cesium 137 from liquid radioactive wastes by using inorganic exchangers using static and dynamic procedures at various concentration of nitric acid and sodium nitrate

    International Nuclear Information System (INIS)

    Cesium 137 was separated from liquid wastes by ion exchange using ammonium molybdenum phosphate, potassium hexa cyano cobalt ferrate, zirconium hydro phosphate and antimony penta oxy hydrate ion exchangers. The investigation was done by static and dynamic procedures. In static procedure required time for reaching the system to equilibrium or ion exchange completion, the measurement of each exchanger, the effect of nitric acid and concentration of sodium nitrate on the capacity of ion exchangers was investigated. Also in dynamic procedure nitric acid and sodium nitrate concentration ratio on the power of and thereof the capacity of each ion exchanger was determined

  2. Spatial variability and Cesium-137 inventories in native forest

    International Nuclear Information System (INIS)

    With the nuclear fission discovery and development of nuclear weapons in 1940s, artificial radioisotopes were introduced in the environment. This contamination is due to worldwide fallout by superficial nuclear tests realized from early 1950s to late 1970s by USA, former URSS, UK, France and China. One of theses radioisotopes that have been very studied is cesium-137. Cesium-137 has a half-life of 30.2 years and its biological behavior is similar to the potassium. The behavior in soil matrix, depth distribution, spatial variability and inventories values of cesium-137 has been determinate for several regions of the world. In Brazil, some research groups have worked on this subject, but there are few works published about theses properties of cesium-137. The aim of this paper was study the depth distribution, spatial variability, and inventory of cesium-137 in native forest. Two native forests (Mata 1 and Mata UEL) were sampling in region of Londrina, PR. The results shows that there is a spatial variability of 40% for Mata 1 and 42% for Mata UEL. The depth distribution of cesium-137 for two forests presented a exponential form, characteristic to undisturbed soil. Cesium-137 inventory determinate for Mata 1 was 358 Bq m-2 and for Mata UEL was 320 Bq m-2. (author)

  3. Sintered bentonite ceramics for the immobilization of cesium- and strontium-bearing radioactive waste

    Science.gov (United States)

    Ortega, Luis Humberto

    The Advanced Fuel Cycle Initiative (AFCI) is a Department of Energy (DOE) program, that has been investigating technologies to improve fuel cycle sustainability and proliferation resistance. One of the program's goals is to reduce the amount of radioactive waste requiring repository disposal. Cesium and strontium are two primary heat sources during the first 300 years of spent nuclear fuel's decay, specifically isotopes Cs-137 and Sr-90. Removal of these isotopes from spent nuclear fuel will reduce the activity of the bulk spent fuel, reducing the heat given off by the waste. Once the cesium and strontium are separated from the bulk of the spent nuclear fuel, the isotopes must be immobilized. This study is focused on a method to immobilize a cesium- and strontium-bearing radioactive liquid waste stream. While there are various schemes to remove these isotopes from spent fuel, this study has focused on a nitric acid based liquid waste. The waste liquid was mixed with the bentonite, dried then sintered. To be effective sintering temperatures from 1100 to 1200°C were required, and waste concentrations must be at least 25 wt%. The product is a leach resistant ceramic solid with the waste elements embedded within alumino-silicates and a silicon rich phase. The cesium is primarily incorporated into pollucite and the strontium into a monoclinic feldspar. The simulated waste was prepared from nitrate salts of stable ions. These ions were limited to cesium, strontium, barium and rubidium. Barium and rubidium will be co-extracted during separation due to similar chemical properties to cesium and strontium. The waste liquid was added to the bentonite clay incrementally with drying steps between each addition. The dry powder was pressed and then sintered at various temperatures. The maximum loading tested is 32 wt. percent waste, which refers to 13.9 wt. percent cesium, 12.2 wt. percent barium, 4.1 wt. percent strontium, and 2.0 wt. percent rubidium. Lower loadings of waste

  4. Pollution of drug-technical materials by cesium-137

    International Nuclear Information System (INIS)

    Drug-technical raw materials are medicinal plants (flowers, folium, grasses, mushrooms, roots, fruits, berry, kidney, cortex), used in pharmacy. To limit receipt cesium-137 in people body in 1993 in the Republic of Belarus were created 'Temporary permission levels of the cesium-137 radionuclides contents in drug-technical raw materials' were created (TPL-1993). The permission levels of cesium-137 are following: for drug-technical raw material (flowers, folium, grass, mushrooms, roots and other plants parts) - 1850 Bq/kg, for dried up fruits and berries - 2590 Bq/kg. (Author)

  5. Synthesis and peculiarities of the cesium zeolite crystal structure (cesite)

    International Nuclear Information System (INIS)

    An attempt is made to synthesize cesium zeolite by introduction of amorphous seed crystals which correspond by composition with cesium-containing zeolite into the aluminosilicate gel, since this method can produce zeolite with a crystal structure it would not adopt under the usual conditions. It is seen that during crystablization upon introduction of a seed crystal the cesium content in zeolite decreases. A more complete structural elucidation of zeolite obtained by the suggested method was carried out by x0ray and IR spectral analyses. The data of x-ray analysis showed that the structures of synthesized zeolite and binary octagonal pores are similar

  6. Effect of kinetic energy on the doping efficiency of cesium cations into superfluid helium droplets

    International Nuclear Information System (INIS)

    We present an experimental investigation of the effect of kinetic energy on the ion doping efficiency of superfluid helium droplets using cesium cations from a thermionic emission source. The kinetic energy of Cs+ is controlled by the bias voltage of a collection grid collinearly arranged with the droplet beam. Efficient doping from ions with kinetic energies from 20 eV up to 480 V has been observed in different sized helium droplets. The relative ion doping efficiency is determined by both the kinetic energy of the ions and the average size of the droplet beam. At a fixed source temperature, the number of doped droplets increases with increasing grid voltage, while the relative ion doping efficiency decreases. This result implies that not all ions are captured upon encountering with a sufficiently large droplet, a deviation from the near unity doping efficiency for closed shell neutral molecules. We propose that this drop in ion doping efficiency with kinetic energy is related to the limited deceleration rate inside a helium droplet. When the source temperature changes from 14 K to 17 K, the relative ion doping efficiency decreases rapidly, perhaps due to the lack of viable sized droplets. The size distribution of the Cs+-doped droplet beam can be measured by deflection and by energy filtering. The observed doped droplet size is about 5 × 106 helium atoms when the source temperature is between 14 K and 17 K

  7. Management of cesium loaded AMP- Part I preparation of 137Cesium concentrate and cementation of secondary wastes

    International Nuclear Information System (INIS)

    Separation of 137cesium from High Level Waste can be achieved by use of composite-AMP, an engineered form of Ammonium Molybdo-Phosphate(AMP). Direct vitrification of cesium loaded composite AMP in borosilicate glass matrix leads to separation of water soluble molybdate phase. A proposed process describes two different routes of selective separation of molybdates and phosphate to obtain solutions of cesium concentrates. Elution of 137Cesium from composite-AMP by decomposing it under flow conditions using saturated barium hydroxide was investigated. This method leaves molybdate and phosphate embedded in the column but only 70% of total cesium loaded on column could be eluted. Alternatively composite-AMP was dissolved in sodium hydroxide and precipitation of barium molybdate-phosphate from the resultant solution, using barium nitrate was investigated by batch methods. The precipitation technique gave over 99.9% of 137Cesium activity in solutions, free of molybdates and phosphates, which is ideally suited for immobilization in borosilicate glass matrix. Detailed studies were carried out to immobilize secondary waste of 137Cesium contaminated barium molybdate-phosphate precipitates in the slag cement matrix using vermiculite and bentonite as admixtures. The cumulative fraction of 137Cs leached from the cement matrix blocks was 0.05 in 140 days while the 137Cs leach rate was 0.001 gm/cm2/d. (author)

  8. GANIL Workshop on Ion Sources

    International Nuclear Information System (INIS)

    The proceedings of the GANIL Workshop on Ion Sources held at GANIL - Caen on 18-19 March 1999 contains 13 papers aiming at improving the old source operation and developing new types of sources for nuclear research and studies of ion physics. A number of reports are devoted to applications like surface treatment, ion implantation or fusion injection. The 1+→n+ transformation, charged particle transport in ECR sources, addition of cesium and xenon in negative ion sources and other basic issues in ion sources are also addressed

  9. An Inorganic Microsphere Composite for the Selective Removal of 137 Cesium from Acidic Nuclear Waste Solutions 2: Bench-Scale Column Experiments, Modeling, and Preliminary Process Design

    Energy Technology Data Exchange (ETDEWEB)

    Troy J. Tranter; T. A. Vereschagina; V. Utgikar

    2009-03-01

    A new inorganic ion exchange composite for removing radioactive cesium from acidic waste streams has been developed. The new material consists of ammonium molybdophosphate, (NH4)3P(Mo3O10)4?3H2O (AMP), synthesized within hollow aluminosilicate microspheres (AMP-C), which are produced as a by-product from coal combustion. The selective cesium exchange capacity of this inorganic composite was evaluated in bench-scale column tests using simulated sodium bearing waste solution as a surrogate for the acidic tank waste currently stored at the Idaho National Laboratory (INL). Total cesium loading on the columns at saturation agreed very well with equilibrium values predicted from isotherm experiments performed previously. A numerical algorithm for solving the governing partial differential equations (PDE) for cesium uptake was developed using the intraparticle mass transfer coefficient obtained from previous batch kinetic experiments. Solutions to the governing equations were generated to obtain the cesium concentration at the column effluent as a function of throughput volume using the same conditions as those used for the actual column experiments. The numerical solutions of the PDE fit the column break through data quite well for all the experimental conditions in the study. The model should therefore provide a reliable prediction of column performance at larger scales.

  10. Biosorption of uranium, radium, and cesium

    International Nuclear Information System (INIS)

    Some fundamental aspects of the biosorption of metals by microbial cells were investigated. These studies were carried out in conjunction with efforts to develop a process to utilize microbial cells as biosorbents for the removal of radionuclides from waste streams generated by the nuclear fuel cycle. It was felt that an understanding of the mechanism(s) of metal uptake would potentially enable the enhancement of the metal uptake phenomenon through environmental or genetic manipulation of the microorganisms. Also presented are the results of a preliminary investigation of the applicability of microorganisms for the removal of 137cesium and 226radium from existing waste solutions. The studies were directed primarily at a characterization of uranium uptake by the yeast, Saccharomyces cerevisiae, and the bacterium, Pseudomonas aeruginosa

  11. Structure of double hafnium and cesium sulfate

    International Nuclear Information System (INIS)

    The structure of a compound whose formula according to the structural investigation is Cssub(2+x)Hf(SOsub(4))sub(2+x)(HSOsub(4))sub(2-x)x3Hsub(2)O (x approximately 0.7) (a=10.220, b=12.004, c=15.767 A, space group Pcmn) is determined by diffractometric data (2840 reflections, anisotropic refinement, R=0.087). It is build of complex unions [Hf(SO4)4H2O]4-, Cs+ cations and water molecules. Eight O atoms surrounding Hf atom (dodecahedron Hf-O 2.10-2.22 A) belong to four sulphate groups and water molecule. Three sulphate groups are bidentate-cyclic, and one group - monodentate relative to Hf. The structure has a cesium deficit in particular positions

  12. Double manganese(III) cesium triphosphate

    International Nuclear Information System (INIS)

    Double triphosphates have been identified in research on interactions in the P2O5-M2O3-Cs2O-H2O system, where M(III) = Al, Ga, Cr, Fe, at 570-770K, which have the M(III)Cs2 - P3O10 composition; here we report the identification of a new phase made under analogous conditions in a system containing Mn(III) together with some of its physicochemical properties. The product was analyzed for phosphorus by a colorimetric method, for manganese by titration with EDTA, and for cesium by atomic absorption. The x-ray phase analysis was performed with a DRON-3.0 diffractometer. The IR spectra were recorded. Thermogravimetry indicates that the product is MnCs2P3O10·H2O

  13. Low-work-function surfaces produced by cesium carbonate decomposition

    Science.gov (United States)

    Briere, T. R.; Sommer, A. H.

    1977-01-01

    Cesium carbonate (Cs2CO3) was heated to the decomposition temperature of approximately 600 C. The nonvolatile decomposition products were condensed on a nickel substrate while the carbon dioxide was removed by pumping. The deposited material is characterized by an effective work function of between 1.05 and 1.15 eV at 450 K and by photoemission in the visible and near-infrared region of the spectrum. It is suggested that the deposited material consists of Cs2O, possibly Cs2O2, and adsorbed cesium. Silver, evaporated from a heated silver bead, produced the typical photoemissive and thermionic properties of a silver-oxygen-cesium (S-1) photocathode. The material may be of interest for thermionic energy converters and for the formation of silver-oxygen-cesium photocathodes.

  14. Cesium iodide crystals fused to vacuum tube faceplates

    Science.gov (United States)

    Fleck, H. G.

    1964-01-01

    A cesium iodide crystal is fused to the lithium fluoride faceplate of a photon scintillator image tube. The conventional silver chloride solder is then used to attach the faceplate to the metal support.

  15. The promotional effects of cesium promoter on higher alcohol synthesis from syngas over cesium-promoted Cu/ZnO/Al2O3 catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Jie; Cai, Qiuxia; Wan, Yan; Wan, Shaolong; Wang, Li; Lin, Jingdong; Mei, Donghai; Wang, Yong

    2016-09-02

    In this study, the promotional effects of cesium promoter on higher alcohol (C2+OH) synthesis from syngas over Cs-Cu/ZnO/Al2O3 catalysts were investigated using a combined experimental and theoretical density functional theory (DFT) calculation method. In the presence of cesium, the C2+OH productivity increases from 77.1 g•kgcat-1•h-1 to 157.3 g•kgcat-1•h-1 at 583 K due to the enhancement of the initial C–C bond formation. Detailed analysis of chain growth probabilities (CGPs) confirms that initial C–C bond formation is the rate-determining step in the temperature range of 543-583 K. Addition of cesium promoter significantly increases the productivities of 2-methyl-1-propanol, while the CGPs values (C3* to 2-methyl-C3*) is almost unaffected. With the assistance of cesium promoter, the CGPs of the initial C–C bond formation step (C1* to C2*) could be increased from 0.13 to 0.25 at 583 K. DFT calculations indicate that the initial C–C bond formation is mainly contributed by the HCO+HCO coupling reaction over the ZnCu(211) model surface. In the presence of the Cs2O, the stabilities of key reaction intermediates such as HCO and H2CO are enhanced which facilitates both HCO+HCO and HCO+H2CO coupling reaction steps with lower activation barriers over the Cs2O-ZnCu(211) surface. The promotional effects of cesium on the C2+OH productivity are also benefited from the competitive CH+HCO coupling reaction over CH hydrogenation that leads to lower alkane formation. In addition, Bader charge analysis suggests that the presence of cesium ions would facilitate the nucleophilic reaction between HCO and H2CO for initial C–C bond formation. This work was supported by the National Natural Science Foundation of China (No. 91545114 and No. 91545203). We appreciate the joint PhD scholarship support from the China Scholarship Council. The authors would also like to thank the support from Collaborative Innovation Center of Chemistry for Energy Materials (2011-iChEM). DM

  16. Kelvin Probe Studies of Cesium Telluride Photocathode for AWA Photoinjector

    OpenAIRE

    Wisniewski, Eric; Velazquez, Daniel; Yusof, Zikri; Spentzouris, Linda; Terry, Jeff; Harkay, Katherine

    2012-01-01

    Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch (~50 nC) in a long bunch train. Here, we present a study of the work function of cesium telluride photocathode using the Kelvin Probe technique. The study incl...

  17. Adsorption Behaviour of Liquid 4He on Cesium Substrates

    OpenAIRE

    Iov, Valentin

    2004-01-01

    The aim of this thesis is to investigate the wetting properties of 4He on cesium substrates using optical and electrical methods. Due to the fact that the cesium substrates are deposited at low temperatures onto a thin silver underlayer, it is necessary firstly to study and understand the adsorption of helium on silver. The work presented here is structured as follows: some of the fundamental concepts on the theory of physisorbed films, such as van der Waals interaction, adsorption isotherms ...

  18. Colloid stable sorbents for cesium removal: preparation and application of latex particles functionalized with transition metals ferrocyanides.

    Science.gov (United States)

    Avramenko, Valentin; Bratskaya, Svetlana; Zheleznov, Veniamin; Sheveleva, Irina; Voitenko, Oleg; Sergienko, Valentin

    2011-02-28

    In this paper we suggest a principally new approach to preparation of colloid stable selective sorbents for cesium uptake using immobilization of transition metals (cobalt, nickel, and copper) ferrocyanides in nanosized carboxylic latex emulsions. The effects of ferrocyanide composition, pH, and media salinity on the sorption properties of the colloid stable sorbents toward cesium ions were studied in solutions containing up to 200 g/L of sodium nitrate or potassium chloride. The sorption capacities of the colloid sorbents based on mixed potassium/transition metals ferrocyanides were in the range 1.3-1.5 mol Cs/mol ferrocyanide with the highest value found for the copper ferrocyanide. It was shown that the obtained colloid-stable sorbents were capable to penetrate through bulk materials without filtration that made them applicable for decontamination of solids, e.g. soils, zeolites, spent ion-exchange resins contaminated with cesium radionuclides. After decontamination of liquid or solid radioactive wastes the colloid-stable sorbents can be easily separated from solutions by precipitation with cationic flocculants providing localization of radionuclides in a small volume of the precipitates formed. PMID:21208744

  19. Study of strontium and cesium migration in fractured crystalline rock

    International Nuclear Information System (INIS)

    The purpose of this investigation has been to study the retardation and dilution of non-active strontium and cesium relative to a non-absorbing substance (iodide) in a well-defined fracture zone in the Finnsjoen field research area. The investigation was carried out in a previously tracer-tested fracture zone. The study has encompassed two separate test runs with prolonged injection of strontium and iodide and of cesium and iodide. The test have shown that: - Strontium is not retarded, but rather absorbed to about 40% at equilibrium. - At injection stop, 36.3% of the injected mass of strontium has been absorbed and there is no deabsorption. -Cesium is retarded a factor of 2-3 and absorbed to about 30% at equilibrium. - At injection stop, 39.4% of the injected mass of cesium has been absorbed. Cesium is deabsorbed after injection stop (400h) and after 1300 hours, only 22% of the injected mass of cesium is absorbed. (author)

  20. Seasonal variation of cesium 134 and cesium 137 in semidomestic reindeer in Norway after the Chernobyl accident

    Directory of Open Access Journals (Sweden)

    I.M. H. Eikelmann

    1990-09-01

    Full Text Available The Chernobyl accident had a great impact on the semidomestic reindeer husbandry in central Norway. Seasonal differences in habitat and diet resulted in large variations in observed radiocesium concentrations in reindeer after the Chernobyl accident. In three areas with high values of cesium-134 and cesium-137 in lichens, the main feed for reindeer in winter, reindeer were sampled every second month to monitor the seasonal variation and the decrease rate of the radioactivity. The results are based on measurements of cesium-134 and cesium-137 content in meat and blood and by whole-body monitoring of live animals. In 1987 the increase of radiocesium content in reindeer in Vågå were 4x from August to January. The mean reductions in radiocesium content from the winter 1986/87 to the winter 1987/88 were 32%, 50% and 43% in the areas of Vågå, Østre-Namdal and Lom respectively.

  1. A theoretical analysis of parity violation induced by neutral currents in atomic cesium

    Science.gov (United States)

    Bouchiat, C.; Piketty, C. A.; Pignon, D.

    1983-07-01

    In this paper we give a theoretical analysis of the parity violation phenomena in nS - n'S transitions in atomic cesium induced by the electron-nucleus neutral-current interaction. The actual observation of parity violation consists in the measurement of an interference between the p.v. electric dipole amplitude Elpv with the electric amplitude induced by a static electric field. Our theoretical work must then include a calculation of the diagonal and non-diagonal polarizabilities of the states of atomic cesium. We have used a one-electron model proposed by Norcross which incorporates some many-body effects like the electric screening induced by the core polarization in a semi-empirical way. Our calculated values of the diagonal and non-diagonal polarizabilities of the nS states are in good agreement with the existing measurements; this confirms the already well-established success of the model in predicting the radiative transitions in cesium. We present theoretical arguments supported by detailed numerical computations showing that the one-particle matrix element of the parity-violating electron-nucleus interaction and the parity-violating electric dipole amplitude Elpv itself weakly depend on the shape of the one-electron potential provided the binding energies of the valence states are reproduced accurately. Furthermore it turns out that because of a compensation mechanism, the parity-violating transition is induced by the radiation field outside the ion core region where the screening can be described simply in terms of the measurable cesium ion polarizability. Our results are then used to extract, from the Ecole Normale Supérieure experiment, a value of the weak charge Qw = -57.1 ± 9.4 (r.m.s. statistical deviation) ± 4.7 (systematic uncertainty). This number is to be compared with the prediction of the Weinberg-Salam model with electro-weak radiative corrections: Qw = -68.6 ± 3.0. A general discussion of the uncertainties of the atomic physics

  2. Luminescent and thermochromic properties of tellurium(IV) halide complexes with cesium

    Science.gov (United States)

    Sedakova, T. V.; Mirochnik, A. G.

    2016-02-01

    The spectral-luminescent and thermochromic properties of complex compounds of the composition Cs2TeHal6 (Hal = Cl, Br, I) are studied. The interrelation between the geometric structure and spectral-luminescent properties is studied using the example on complex compounds of tellurium(IV) halides with cesium. The Stokes shift and the luminescence intensity of Te(IV) ions with island octahedral coordination are found to depend on the position of the A band in the luminescence excitation spectra, the diffuse reflection, and the energy of the luminescent 3 P 1 → 1 S 0 transition of the tellurium(IV) ion. The maximum luminescence intensity and the minimum Stokes shift at 77 and 300 K are observed for Cs2TeCl6. The geometrical and electronic factors responsible for luminescence intensification in Te(IV) complexes under study are analyzed.

  3. Selective removal of cesium and strontium using porous frameworks from high level nuclear waste.

    Science.gov (United States)

    Aguila, Briana; Banerjee, Debasis; Nie, Zimin; Shin, Yongsoon; Ma, Shengqian; Thallapally, Praveen K

    2016-05-21

    Efficient and cost-effective removal of radioactive (137)Cs and (90)Sr found in spent fuel is an important step for safe, long-term storage of nuclear waste. Solid-state materials such as resins and titanosilicate zeolites have been assessed for the removal of Cs and Sr from aqueous solutions, but there is room for improvement in terms of capacity and selectivity. Herein, we report the Cs(+) and Sr(2+) exchange potential of an ultra stable MOF, namely, MIL-101-SO3H, as a function of different contact times, concentrations, pH levels, and in the presence of competing ions. Our preliminary results suggest that MOFs with suitable ion exchange groups can be promising alternate materials for cesium and strontium removal. PMID:27055254

  4. Particle desorption of non-conducting surfaces by heavy ions of high energy

    International Nuclear Information System (INIS)

    In the present thesis the desorption of non-conducting surfaces is investigated for krypton, xenon and uranium ions. Targets are europium oxide, cesium iodide, oxophenyl arsenic and manganese gluconate. (BHO)

  5. Dose mapping experiments of refurbished cesium irradiator

    International Nuclear Information System (INIS)

    Full text: Cesium irradiator is a technology demonstration facility for irradiation of food commodities to achieve various purposes like control of sprouting in onion and potato, insect disinfestations of cereals and pulses, quarantine treatment of fresh fruits and vegetables and shelf life extension of perishable foods. The facility was installed in 1968 and recently refurbished with the new control console. The current source strength (137Cs) of the irradiator is 44.3 kCi. The real success of irradiation of food commodities lies in the adequate delivery of radiation dose to achieve the particular purpose of irradiation. Therefore, evaluation of dose distribution pattern in the product trays of the irradiation facility is of paramount importance. Two sets of dose mapping experiments of the product trays of the facility were carried out to find out the dose distribution profile and dose uniformity ratio. Reference standard dosimeter Fricke was used for the experiment. The standardized ionic concentrations of Fricke dosimeter are Ferrous Ammonium Sulphate (FeSO4(NH4)2SO4 6H2O ) - 1 mM, Sodium Chloride (NaCl) - 1 mM, Sulphuric acid (H2SO4) - 400 mM. The Optical Density (O.D) evaluation was carried out using Spectrophotometry with wave length of 304 nm. The dosimetry tray was partitioned into two planes namely bottom plane and top plane using card-board sheets. Polypropylene vials containing Fricke solution were prepared and fixed on the planes. Each plane was containing nine numbers of dosimeters. The product thickness was around 9 cm. The temperatures of irradiation and measurements were 30 deg C and 28 deg C respectively. The first set of experiment was intended to find out the dose distribution profile throughout the irradiation chamber. The dose rate at Dmin position was observed as 3.69 Gy/min with a poor Dose Uniformity Ratio (DUR) of 6.5. In order to improve the dose rate and DUR the second set of the experiment was carried out with modified product geometry

  6. Kinetic and Equilibrium Studies of Cesium-137 Adsorption on Olive Waste from Aqueous Solutions Kinetic and Equilibrium Studies of Cesium-137 Adsorption on Olive Waste from Aqueous Solutions

    International Nuclear Information System (INIS)

    The agricultural by-product olive pomace either in its raw material or carbonized form was used for the removal of 137Cs from aqueous solutions. Experimental studies were conducted to evaluate and optimize some affecting factor such as contact time, adsorbent dosage, ph value and initial 137Cs concentration ions. The sorption process was described by pseudo first-order, pseudo second-order and Intra-particle diffusion models. Data have been interpreted in terms of Langmuir, Freundlich and Dubinin-Radushkevich (D-R) isotherms. The obtained data showed that 120 minutes are sufficient time to attain equilibrium and maximum % removal of 137Cs was found 80% and 99% for raw olive pomace and its carbonized form, respectively. The maximum sorption capacity of raw and carbonized adsorbent for cesium removal was 0.360 and 0.565 mol/g respectively.

  7. Improvement of cesium retention in uranium dioxide by additional phases

    International Nuclear Information System (INIS)

    The objective of this study is to improve the cesium retention in nuclear fuel. A bibliographic survey indicates that cesium is rapidly released from uranium dioxide in an accident condition. At temperatures higher than 1500 deg C or in oxidising conditions, our experiments show the difficulty of maintaining cesium inside simulated fuel. Two ternary systems are potentially interesting for the retention of cesium and to reduce the kinetics of release from the fuel: Cs2O-Al2O3-SiO2 et Cs2O-ZrO2-SO2. The compounds CsAISi2O6 and Cs2ZrSi6O15 were studied from 1200 deg C to 2000 deg C by thermogravimetric analysis. The volumetric diffusion coefficients of cesium in these structures, in solid state as well as in liquid one, were measured. A fuel was sintered with (Al2O3 + SiO2) or (ZrO2 + SiO2) and the intergranular phase was characterized. In the presence of (Al2O3 + SiO2), the sintering is realized at 1610 deg C in H2. It is a liquid phase sintering. On the other end, with (ZrO2 + SiO2), the sintering is a low temperature one in oxidising atmosphere. Finally, cesium containing simulated fuels were produced with these additives. According to the effective diffusion coefficients that were measured, the additives improved the retention of cesium. We have predicted the improvement that could be hoped for in a nuclear reactor, depending on the dispersion of the intergranular additives, the temperature and the degree of oxidation of the UO2+x. We wait for a factor of 2 for x=0 and more than 8 for x=0.05, up to 2000 deg C. (author). 148 refs., 122 figs., 34 tabs

  8. Cesium and strontium in Black Sea macroalgae

    International Nuclear Information System (INIS)

    The trace level of metals and particularly radioactive ones should be monitored to evaluate the transfer along the trophic chain, assess the risk for biota and can be used for global changes assessment. Plants respond rapidly to all changes in the ecosystem conditions and are widely used as indicators and predictors for changes in hydrology and geology. In this work we represent our successful development and applications of a methodology for monitoring of stable and radioactive strontium and cesium in marine biota (Black Sea algae's). In case of radioactive release they are of high interest. We use ED-XRF, gamma spectrometers and LSC instrumentation and only 0.25 g sample. Obtained results are compared with those of other authors in same regions. The novelty is the connection between the radioactive isotopes and their stable elements in algae in time and space scale. All our samples were collected from Bulgarian Black Sea coast. - Highlights: • An extraction chromatography method for radiochemical separation of Sr and Cs. • Assessment of Sr and Cs accumulation capacity of six Black Sea macroalgae species. • Connection between the isotopes and their stable elements content in algae. • Assessment of Sr and Cs content in ecosystems along the Bulgarian coast

  9. Cesium-137 levels detected in Georgia otters

    International Nuclear Information System (INIS)

    Beginning in the 1940's and continuing through the 50's and early 60's, nuclear devices were tested by aerial detonation in the United States and other countries around the world. Cesium-137 (137Cs) is one of the most important radionuclide by-products due to its abundance and slow decay (30-year half-life). The uptake of 137Cs in animal tissue is the result of its similarity to potassium. The somatic and genetic effects of 137Cs, along with its effect on reproductive cells, can pose great hazards to wildlife species. A reported buildup of 137Cs in white-tailed deer in the lower coastal plain of Georgia during the 1960's was followed by a gradual decline during the 1970's. Although numerous studies have involved terrestrial mammals of Georgia, few have involved aquatic mammals such as the river otter. With continued atmospheric testing by some foreign countries and the increased use of nuclear power as an energy source, there is a need for continued monitoring of radionuclides in wildlife to ascertain the quality of the environment. This study was initiated as part of an overall study of environmental pollutants in the river otter of Georgia and deals with analysis of the 137Cs accumulations in this species

  10. Micro-PIXE evaluation of radioactive cesium transfer in contaminated soil samples

    International Nuclear Information System (INIS)

    Highlights: • There are radioactively contaminated soils having a radioactive cesium transfer of 0.01. • Micro-PIXE analysis has revealed an existence of phosphorus in a contaminated soil. • Radioactive cesium captured by phosphorus compound would be due to radioactive transfer. -- Abstract: Micro-PIXE analysis has been performed on two soil samples with high cesium activity concentrations. These soil samples were contaminated by fallout from the accident at Fukushima Daiichi Nuclear Power Plant. One exhibits a radioactive cesium transfer of ∼0.01, and the other shows a radioactive cesium transfer of less than 0.001, even though both samples have high cesium activity concentrations exceeding 10,000 Bq/kg. X-ray spectra and elemental images of the soil samples revealed the presence of chlorine, which can react with cesium to produce an inorganic soluble compound, and phosphorus-containing cesium-capturable organic compounds

  11. A fundamental study on cesium migration to sodium at low temperature

    International Nuclear Information System (INIS)

    Our experiment study aims to understand the behavior of cesium in severe accident of sodium cooled fast breeder reactor, especially cesium migration rate to sodium. In past study, exact migration rate of cesium to sodium has not been reported because of difficulty of the cesium-sodium interfacial area evaluations of gas bubble. In this study, we developed a pool-type experimental apparatus which can simplify the shape of interfacial area, and measured cesium migration rate in a low temperature range of 200degC to 300degC. The cesium migration rates obtained under the condition that the cesium mixed argon gas flow is the same temperature with sodium vary in the range of 10-3 - 10-1 mol/m2min and increase with increasing the system temperature. The difference of cesium migration rates between non-oxidized sodium surface and oxidized sodium surface is also clearly observed. (author)

  12. Viscosity and crystallization mechanism of cesium loaded iron phosphate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, Kitheri, E-mail: joskit@igcar.gov.in [Chemistry Group, IGCAR, Kalpakkam 603 102 (India); Kutty, K.V. Govindan [Chemistry Group, IGCAR, Kalpakkam 603 102 (India); Goswami, M.C. [National Metallurgical Laboratory, Jamshedpur 831 007 (India); Rao, P.R. Vasudeva [Chemistry Group, IGCAR, Kalpakkam 603 102 (India)

    2014-07-01

    Highlights: • Melt viscosity of cesium loaded iron phosphate glasses is measured and reported for the first time. • Viscosity – temperature followed Arrhenius model. • Activation energy of viscous flow is strongly correlated to glass transition temperature of the glasses. • Process of crystallization of cesium loaded glass by approximation-free kinetic method to understand the mechanism. • Cesium loaded IPG and IPG shows bulk crystallization mechanism. - Abstract: This paper describes the melt viscosity behaviour and the crystallization mechanism of a series of iron phosphate glasses. High temperature viscosity measurements were carried out on pristine iron phosphate glass and a series of cesium loaded iron phosphate glasses in order to understand the effect of addition of Cs{sub 2}O on viscosity of iron phosphate glasses. Activation energy of viscous flow was estimated from the experimental data by applying Arrhenius model of viscosity–temperature relationship. Activation energy of viscous flow is observed to be strongly correlated to glass transition temperature of these glasses. Fragility of iron phosphate and cesium loaded iron phosphate glass systems were also evaluated in region of high temperature. Crystallization of these glasses was studied using thermal analysis techniques. Temperature integral approximation free method was utilized to evaluate the kinetic parameters such as activation energy of crystallization (E{sub c}) and Avrami exponent (n). The value of Avrami exponent ‘n’ obtained showed that the glasses under present study crystallize via bulk crystallization mechanism, i.e., nucleation and three dimensional growth.

  13. Cesium corrosion process in Fe–Cr steel

    International Nuclear Information System (INIS)

    A cesium corrosion out-pile test was performed to Fe–Cr steel in a simulated fuel pin environment. In order to specify the corrosion products, the corroded area was analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). A cesium corrosion process in Fe–Cr steel was successfully developed proceeding from both experimental results and thermochemical consideration. The corroded area was mainly formed by Fe layer and Fe depleted oxidized layer. The Fe depleted oxidized layer was formed by Cr0.5Fe0.5 and Cr2O3. The presumed main corrosion reactions were 2Cr+2/3 O2→Cr2O3(ΔG650°C=-894.1kJ/mol) and Cr23C6+46Cs+46O2→23Cs2CrO4+6C(ΔG650°C=-25018.1kJ/mol). Factors of these reactions are chromium, carbon, oxygen and cesium. Therefore, cesium corrosion progression must be dependent on the chromium content, carbon content in the steel, the supply rate of oxygen and temperature which correlated with the diffusion rate of cesium and oxygen into the specimen

  14. Viscosity and crystallization mechanism of cesium loaded iron phosphate glasses

    International Nuclear Information System (INIS)

    Highlights: • Melt viscosity of cesium loaded iron phosphate glasses is measured and reported for the first time. • Viscosity – temperature followed Arrhenius model. • Activation energy of viscous flow is strongly correlated to glass transition temperature of the glasses. • Process of crystallization of cesium loaded glass by approximation-free kinetic method to understand the mechanism. • Cesium loaded IPG and IPG shows bulk crystallization mechanism. - Abstract: This paper describes the melt viscosity behaviour and the crystallization mechanism of a series of iron phosphate glasses. High temperature viscosity measurements were carried out on pristine iron phosphate glass and a series of cesium loaded iron phosphate glasses in order to understand the effect of addition of Cs2O on viscosity of iron phosphate glasses. Activation energy of viscous flow was estimated from the experimental data by applying Arrhenius model of viscosity–temperature relationship. Activation energy of viscous flow is observed to be strongly correlated to glass transition temperature of these glasses. Fragility of iron phosphate and cesium loaded iron phosphate glass systems were also evaluated in region of high temperature. Crystallization of these glasses was studied using thermal analysis techniques. Temperature integral approximation free method was utilized to evaluate the kinetic parameters such as activation energy of crystallization (Ec) and Avrami exponent (n). The value of Avrami exponent ‘n’ obtained showed that the glasses under present study crystallize via bulk crystallization mechanism, i.e., nucleation and three dimensional growth

  15. The diffusion of cesium, strontium, and europium in silicon carbide

    Science.gov (United States)

    Dwaraknath, S. S.; Was, G. S.

    2016-08-01

    A novel multi-layer diffusion couple was used to isolate the diffusion of strontium, europium and cesium in SiC without introducing radiation damage to SiC and at concentrations below the solubility limit for the fission products in SiC. Diffusion occurred by both bulk and grain boundary pathways for all three fission products between 900∘ C and 1 ,300∘ C. Cesium was the fastest diffuser below 1 ,100∘ C and the slowest above this temperature. Strontium and europium diffusion tracked very closely as a function of temperature for both bulk and grain boundary diffusion. Migration energies ranged from 1.0 eV to 5.7 eV for bulk diffusion and between 2.2 eV and 4.7 eV for grain boundary diffusion. These constitute the first measurements of diffusion of cesium, europium, and strontium in silicon carbide, and the magnitude of the cesium diffusion coefficient supports the premise that high quality TRISO fuel should have minimal cesium release.

  16. ROBUSTNESS OF THE CSSX PROCESS TO FEED VARIATION: EFFICIENT CESIUM REMOVAL FROM THE HIGH POTASSIUM WASTES AT HANFORD

    International Nuclear Information System (INIS)

    This contribution finds the Caustic-Side Solvent Extraction (CSSX) process to be effective for the removal of cesium from the Hanford tank-waste supernatant solutions. The Hanford waste types are more challenging than those at the Savannah River Site (SRS) in that they contain significantly higher levels of potassium, the chief competing ion in the extraction of cesium. By use of a computerized CSSX thermodynamic model, it was calculated that the higher levels of potassium depress the cesium distribution ratio (DCs), as validated to within ±11% by the measurement of DCs values on various Hanford waste-simulant compositions. A simple analog model equation that can be readily applied in a spreadsheet for estimating the DCs values for the varying waste compositions was developed and shown to yield nearly identical estimates as the computerized CSSX model. It is concluded from the batch distribution experiments, the physical-property measurements, the equilibrium modeling, the flowsheet calculations, and the contactor sizing that the CSSX process as currently formulated for cesium removal from alkaline salt waste at the SRS is capable of treating similar Hanford tank feeds, albeit with more stages. For the most challenging Hanford waste composition tested, 31 stages would be required to provide a cesium decontamination factor (DF) of 5000 and a concentration factor (CF) of 2. Commercial contacting equipment with rotor diameters of 10 in. for extraction and 5 in. for stripping should have the capacity to meet throughput requirements, but testing will be required to confirm that the needed efficiency and hydraulic performance are actually obtainable. Markedly improved flowsheet performance was calculated based on experimental distribution ratios determined for an improved solvent formulation employing the more soluble cesium extractant BEHBCalixC6 used with alternative scrub and strip solutions, respectively 0.1 M NaOH and 0.010 M boric acid. The improved solvent and

  17. Dissociative excitation of cesium atom upon e-CsOH collisions

    International Nuclear Information System (INIS)

    The process of dissociative excitation of cesium atom in collisions with mono-kinetic molecules of cesium hydroxide is studied. It is established that behaviour of dissociative excitations the cesium atom in spectral series corresponds of to the grade dependence of cross sections on the main quantum number of the upper level. The values of constants, characterizing the behaviour of cross sections in the eight spectral series of the cesium atom are determined

  18. The stability under irradiation of hollandite ceramics, specific radioactive cesium-host waste forms

    International Nuclear Information System (INIS)

    Investigations are currently performed on matrices for the specific immobilization of long-lived radionuclides such as fission products resulting from an enhanced reprocessing of spent fuel. Hollandite (nominally BaA2Ti6O16), one of the phases constituting SYNROC, receives renewed interest as specific Cs host wasteform. The radioactive cesium isotopes decay involves the emission of β particles, γ rays and the transmutation of Cs to stable Ba ions. This study deals with the synthesis of hollandite ceramics by oxide route and single crystals by a flux method having the BaxCsy(Al,Fe)2x+yTi8-2x-yO16 composition type (l≤x≤1.28; 0≤y≤0.28). The influence of the hollandite chemical composition on the hollandite structure and microstructure is studied. To estimate the hollandite radiation resistance, external electron irradiation experiments, simulating the β particles emitted by radioactive cesium, were carried on single phase materials. The radiation effects were characterized by electron paramagnetic resonance (EPR) and Moessbauer spectroscopy. (authors)

  19. Sorption of cesium and strontium from concentrated brines by backfill barrier materials

    International Nuclear Information System (INIS)

    The sorption of radionuclides from potentially intruding groundwater at a nuclear waste repository is a major chemical function of backfill barriers. In this study, various materials (including clays, zeolites and an inorganic ion exchanger) were screened for the sorption of the fission products cesium and strontium in concentrated brines. Representative brines A and B for the Waste Isolation Pilot Plant (WIPP), a proposed radioactive waste repository and test facility in bedded salt were used. Sorption properties were quantified using empirical distribution coefficients, k/sub d/. Of the materials examined, sodium titanate had the highest k/sub d/ for the sorption of Sr(II) in both brine A (k/sub d/ = 125 ml/g) and brine B(k/sub d/ = 500 to 600 ml/g). A mordenite-type zeolite was the most effective getter for Cs(I) in brine A (k/sub d = 27 ml/g), while illite yielded the highest k/sub d/ for Cs(I) in brine B (k/sub d/ = 115 ml/g). The relative merit of these k/sub d/ values is evaluated in terms of calculated estimates of breakthrough times for a backfill barrier containing the getter. Results show that a backfill mixture containing these getters is potentially an effective barrier to the migration of Sr(II) and Cs(I), although further study (especially for the sorption of cesium from brine A) is recommended. Initial mechanistic studies revealed competing ion effects which would support an ion exchange mechanism. K/sub d/'s were constant over a Sr(II) concentration range of 10-11 to 10-5 M and a Cs(I) concentration range of 10-8 to 10-5 M, supporting the choice of a linear sorption isotherm as a model for the results. Constant batch composition was shown to be attained within one week

  20. Sorption of cesium and strontium from concentrated brines by backfill barrier materials

    Energy Technology Data Exchange (ETDEWEB)

    Winslow, C D

    1981-03-01

    The sorption of radionuclides from potentially intruding groundwater at a nuclear waste repository is a major chemical function of backfill barriers. In this study, various materials (including clays, zeolites and an inorganic ion exchanger) were screened for the sorption of the fission products cesium and strontium in concentrated brines. Representative brines A and B for the Waste Isolation Pilot Plant (WIPP), a proposed radioactive waste repository and test facility in bedded salt were used. Sorption properties were quantified using empirical distribution coefficients, k/sub d/. Of the materials examined, sodium titanate had the highest k/sub d/ for the sorption of Sr(II) in both brine A (k/sub d/ = 125 ml/g) and brine B(k/sub d/ = 500 to 600 ml/g). A mordenite-type zeolite was the most effective getter for Cs(I) in brine A (k/sub d = 27 ml/g), while illite yielded the highest k/sub d/ for Cs(I) in brine B (k/sub d/ = 115 ml/g). The relative merit of these k/sub d/ values is evaluated in terms of calculated estimates of breakthrough times for a backfill barrier containing the getter. Results show that a backfill mixture containing these getters is potentially an effective barrier to the migration of Sr(II) and Cs(I), although further study (especially for the sorption of cesium from brine A) is recommended. Initial mechanistic studies revealed competing ion effects which would support an ion exchange mechanism. K/sub d/'s were constant over a Sr(II) concentration range of 10/sup -11/ to 10/sup -5/ M and a Cs(I) concentration range of 10/sup -8/ to 10/sup -5/ M, supporting the choice of a linear sorption isotherm as a model for the results. Constant batch composition was shown to be attained within one week.

  1. Sorption of cesium and uranium to Feldspar

    International Nuclear Information System (INIS)

    Within safety assessment studies, for nuclear waste disposal in deep geologic formations, calculation for the migration of radionuclides through the geosphere are often carried out with models taking sorption into account. In the past 8 years the insight grew that other physico-chemical processes, besides sorption, could affect migration behaviour. While the currently used transport models were being improved taking either linear or non-linear sorption into account, the coupling of geochemical and transport models came into scope. In spite of these developments models which are still based on the sorption theory are frequently applied in studying migration behaviour of radionuclides. This is caused by the necessity of making preliminary pronouncements, while coupled models are still in stage of development and thermodynamic data are very limited available. Therefore one has to obtain insight in the reliability of the models based on the sorption theory. within the sorption database there is a lack of knowledge about mineralogy, composition of the fluid and the experimental conditions underlying the data. Therefore the Expert Group on geochemical Modelling supported by the Finnish proposal in order to obtain insight in the possible deviation of the sorption coefficients that can be estimated from experiments performed with standard samples, fluid composition and experimental conditions. Nine laboratories from OECD membership countries took part in this intercalibration study. In the framework of the Dutch safety assessment studies the Dutch National Institute of Public health and Environmental protection (RIVM) has decided to participate in this exercise. In this report the results are presented of sorption experiments for cesium and natural Uranium to Feldspar. (H.W.). 4 refs.; 1 fig.; 7 tabs

  2. Cesium in the Savannah River Site environment

    International Nuclear Information System (INIS)

    Cesium in the Savannah River Site Environment is published as a part of the Radiological Assessment Program (RAP). It is the fourth in a series of eight documents on individual radioisotopes released to the environment as a result of Savannah River Site (SRS) operations. The earlier documents describe the environmental consequences of tritium, iodine, and uranium. Documents on plutonium, strontium, carbon, and technetium will be published in the future. These are dynamic documents and current plans call for revising and updating each one on a two-year schedule.Radiocesium exists in the environment as a result of above-ground nuclear weapons tests, the Chernobyl accident, the destruction of satellite Cosmos 954, small releases from reactors and reprocessing plants, and the operation of industrial, medical, and educational facilities. Radiocesium has been produced at SRS during the operation of five production reactors. Several hundred curies of 137Cs was released into streams in the late 50s and 60s from leaking fuel elements. Smaller quantities were released from the fuel reprocessing operations. About 1400 Ci of 137Cs was released to seepage basins where it was tightly bound by clay in the soil. A much smaller quantity, about four Ci. was released to the atmosphere. Radiocesium concentration and mechanisms for atmospheric, surface water, and groundwater have been extensively studied by Savannah River Technology Center (SRTC) and ecological mechanisms have been studied by Savannah River Ecology Laboratory (SREL). The overall radiological impact of SRS releases on the offsite maximum individual can be characterized by total doses of 033 mrem (atmospheric) and 60 mrem (liquid), compared with a dose of 12,960 mrem from non-SRS sources during the same period of time. Isotope 137Cs releases have resulted in a negligible risk to the environment and the population it supports

  3. Cesium in the Savannah River Site environment

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, W.H.; Bauer, L.R.; Evans, A.G.; Geary, L.A.; Murphy, C.E. Jr.; Pinder, J.E.; Strom, R.N.

    1992-03-01

    Cesium in the Savannah River Site Environment is published as a part of the Radiological Assessment Program (RAP). It is the fourth in a series of eight documents on individual radioisotopes released to the environment as a result of Savannah River Site (SRS) operations. The earlier documents describe the environmental consequences of tritium, iodine, and uranium. Documents on plutonium, strontium, carbon, and technetium will be published in the future. These are dynamic documents and current plans call for revising and updating each one on a two-year schedule.Radiocesium exists in the environment as a result of above-ground nuclear weapons tests, the Chernobyl accident, the destruction of satellite Cosmos 954, small releases from reactors and reprocessing plants, and the operation of industrial, medical, and educational facilities. Radiocesium has been produced at SRS during the operation of five production reactors. Several hundred curies of {sup 137}Cs was released into streams in the late 50s and 60s from leaking fuel elements. Smaller quantities were released from the fuel reprocessing operations. About 1400 Ci of {sup 137}Cs was released to seepage basins where it was tightly bound by clay in the soil. A much smaller quantity, about four Ci. was released to the atmosphere. Radiocesium concentration and mechanisms for atmospheric, surface water, and groundwater have been extensively studied by Savannah River Technology Center (SRTC) and ecological mechanisms have been studied by Savannah River Ecology Laboratory (SREL). The overall radiological impact of SRS releases on the offsite maximum individual can be characterized by total doses of 033 mrem (atmospheric) and 60 mrem (liquid), compared with a dose of 12,960 mrem from non-SRS sources during the same period of time. Isotope {sup 137}Cs releases have resulted in a negligible risk to the environment and the population it supports.

  4. Cesium in the Savannah River Site environment

    Energy Technology Data Exchange (ETDEWEB)

    Carlton, W.H.; Bauer, L.R.; Evans, A.G.; Geary, L.A.; Murphy, C.E. Jr.; Pinder, J.E.; Strom, R.N.

    1992-03-01

    Cesium in the Savannah River Site Environment is published as a part of the Radiological Assessment Program (RAP). It is the fourth in a series of eight documents on individual radioisotopes released to the environment as a result of Savannah River Site (SRS) operations. The earlier documents describe the environmental consequences of tritium, iodine, and uranium. Documents on plutonium, strontium, carbon, and technetium will be published in the future. These are dynamic documents and current plans call for revising and updating each one on a two-year schedule.Radiocesium exists in the environment as a result of above-ground nuclear weapons tests, the Chernobyl accident, the destruction of satellite Cosmos 954, small releases from reactors and reprocessing plants, and the operation of industrial, medical, and educational facilities. Radiocesium has been produced at SRS during the operation of five production reactors. Several hundred curies of [sup 137]Cs was released into streams in the late 50s and 60s from leaking fuel elements. Smaller quantities were released from the fuel reprocessing operations. About 1400 Ci of [sup 137]Cs was released to seepage basins where it was tightly bound by clay in the soil. A much smaller quantity, about four Ci. was released to the atmosphere. Radiocesium concentration and mechanisms for atmospheric, surface water, and groundwater have been extensively studied by Savannah River Technology Center (SRTC) and ecological mechanisms have been studied by Savannah River Ecology Laboratory (SREL). The overall radiological impact of SRS releases on the offsite maximum individual can be characterized by total doses of 033 mrem (atmospheric) and 60 mrem (liquid), compared with a dose of 12,960 mrem from non-SRS sources during the same period of time. Isotope [sup 137]Cs releases have resulted in a negligible risk to the environment and the population it supports.

  5. Spins and magnetic moments of rubidium and cesium nuclides far from stability

    International Nuclear Information System (INIS)

    Previous studies at ISOLDE have concerned spins and magnetic moments of neutron-deficient rubidium and cesium isotopes. Here, the main results obtained, and, in the case of cesium, new moment measurements are briefly discussed also the results from measurements on neutron-rich nuclides of rubidium and cesium. (orig./AH)

  6. Environmental application of cesium-137 irradiation technology: Sludges and foods

    Science.gov (United States)

    Sivinski, Jacek S.

    Several activities have been undertaken to investigate and implement the use of the military byproduct cesium-137 in ways which benefit mankind. Gamma radiation from cesium-137 has been shown to be effective in reducing pathogens in sewage sludge to levels where reuse of the material in public areas meets current regulatory criteria for protection of public health. Food irradiation at doses of 10 kGy or less have been found by international expert committees to be wholesome and safe for human consumption. Cesium-137 can be used as a means of enhancing particular properties of various food commodities by means of sterilization, insect disinfestation, delayed senescence and ripening, and sprout inhibition. This paper discusses the U.S. Department of Energy Beneficial Uses Program research and engineering history, as well as current activities and future plans, relating to both sewage sludge and food irradiation.

  7. Environmental application of cesium-137 irradiation technology: sludges and foods

    International Nuclear Information System (INIS)

    Several activities have been undertaken to investigate and implement the use of the military byproduct cesium-137 in ways which benefit mankind. Gamma radiation from cesium-137 has been shown to be effective in reducing pathogens in sewage sludge to levels where reuse of the material in public areas meets current regulatory criteria for protection of public health. Food irradiation at doses of 10 kGy or less have been found by international expert committees to be wholesome and safe for human consumption. Cesium-137 can be used as a means of enhancing particular properties of various food commodities by means of sterilization, insect disinfestation, delayed senescence and ripening, and sprout inhibition. This paper discusses the U.S. Department of Energy Beneficial Uses Program research and engineering history, as well as current activities and future plans, relating to both sewage sludge and food irradiation. (author)

  8. Dating of mine waste in lacustrine sediments using cesium-137

    Science.gov (United States)

    Rember, W. C.; Erdman, T. W.; Hoffmann, M. L.; Chamberlain, V. E.; Sprenke, K. F.

    1993-11-01

    For over a century Medicine Lake in northern Idaho has received heavy-metal-laden tailings from the Coeur d'Alene mining district. Establishing the depositional chronology of the lake bottom sediments provides information on the source and rate of deposition of the tailings. Cesium-137, an isotope produced in the atmosphere by nuclear bomb tests, was virtually absent in the environment prior to 1951, but reached its apex in 1964. Our analysis of cesium-137 in the sediments of Medicine Lake revealed that 14 cm of fine-grained tailings were deposited in the lake from 1951 to 1964 and tailing deposition downstream was greatly reduced by the installation of tailings dams in the district in 1968. Cesium-137 analysis is accomplished by a fairly simple gamma-ray counting technique and should be a valuable tool for analyzing sedimentation in any lacustrine environment that was active during the 1950s and 1960s.

  9. Cesium 137 in oils and plants from Guatemala

    International Nuclear Information System (INIS)

    Since 1990 the project of radioactive and environmental contamination started in Guatemala. Studies about the radioactive contamination levels are made within the framework of this project. Cesium-137 has been an interest radionuclide, because it is a fission product released to the environment by the use of nuclear weapons and nuclear power plants accidents. The sampling consisted in collection of soil and grass in 20 provinces of Guatemala, one point by province, and it was made in 1990. The cesium-137 concentration in the samples, was determined by gamma spectrometry, using an hyper pure germanium detector. The results show the presence of radioactive contamination in soil and grass due to cesium-137, at levels that might be considered as normal. The levels found are not harmful for human health, and its importance is the fact that can be used as reference levels for the environmental radioactivity monitoring in Guatemala

  10. Study of radiatively sustained cesium plasmas for solar energy conversion

    Science.gov (United States)

    Palmer, A. J.; Dunning, G. J.

    1980-01-01

    The results of a study aimed at developing a high temperature solar electric converter are reported. The converter concept is based on the use of an alkali plasma to serve as both an efficient high temperature collector of solar radiation as well as the working fluid for a high temperature working cycle. The working cycle is a simple magnetohydrodynamic (MHD) Rankine cycle employing a solid electrode Faraday MHD channel. Research milestones include the construction of a theoretical model for coupling sunlight in a cesium plasma and the experimental demonstration of cesium plasma heating with a solar simulator in excellent agreement with the theory. Analysis of a solar MHD working cycle in which excimer laser power rather than electric power is extracted is also presented. The analysis predicts a positive gain coefficient on the cesium-xenon excimer laser transition.

  11. On the compartmental modeling of cesium migration in soils

    International Nuclear Information System (INIS)

    The prediction of the migration of radionuclides in soil following deposition after a nuclear accident is important for both external dose and plant uptake prediction. In this paper, the validity conditions of compartment models for cesium migration in soils are investigated. A compartment model is derived from a diffusion-convection model. The model considers free and bound cesium compartments and is applied to measured profiles of 137Cs of undisturbed soil in Northern Greece. It is concluded that the rate of cesium transfer must vary linearly with depth and that from measured equilibrium profiles, the ratios of model parameters can be determined but not the parameters themselves. This model is applied to measured profiles of 137Cs in soil due to wet deposition following the Chernobyl accident

  12. Thallous and cesium halide materials for use in cryogenic applications

    International Nuclear Information System (INIS)

    Certain thallous and cesium halides, either used alone or in combination with other ceramic materials, are provided in cryogenic applications such as heat exchange material for the regenerator section of a closed-cycle cryogenic refrigeration section, as stabilizing coatings for superconducting wires, and as dielectric insulating materials. The thallous and cesium halides possess unusually large specific heats at low temperatures, have large thermal conductivities, are nonmagnetic, and are nonconductors of electricity. They can be formed into a variety of shapes such as spheres, bars, rods, or the like and can be coated or extruded onto substrates or wires. (author)

  13. Modeling of cesium sorption on biotite using cation exchange selectivity coefficients

    Energy Technology Data Exchange (ETDEWEB)

    Kylloenen, Jarkko; Hakanen, Martti; Harjula, Risto; Lehto, Jukka [Helsinki Univ. (Finland). Lab. of Radiochemistry; Lindberg, Antero [Geological Survey of Finland, Espoo (Finland); Vehkamaeki, Marko [Helsinki Univ. (Finland). Lab. of Inorganic Chemistry

    2014-07-01

    For the modeling of cesium sorption on biotite, samples of natural biotite separated from gneissic rocks were converted into monoionic potassium, sodium, and calcium forms, and sorption isotherms for Cs/K, Cs/Na and Cs/Ca exchange were determined at pH 6 and 8 in 10{sup -4}-10{sup -8} M Cs solutions. Selectivity coefficients for Cs/K, Cs/Na, and Cs/Ca ion exchange reactions were calculated from the isotherm data, using the Gaines-Thomas convention. At Cs loadings below 1% of the total ion exchange capacity, the overall selectivity coefficient for Cs/Ca exchange was approximately five and seven orders of magnitude higher than those for Cs/Na and Cs/K exchange, respectively. Based on the selectivity coefficients, the ion exchange isotherms were modeled with the U.S. Geological Survey PhreeqC program, assuming three different types of ion exchange site: sites on the basal planes on biotite crystal surfaces with 95% site abundance, probable interlayer sites on crystal edges [frayed edge sites (FESs)] (0.02%) and third-type sites (5%), the physical background of which is unclear. Of these three types, the FES sites were superior in Cs selectivity, while the planar sites exhibited the lowest selectivity, and the third-type sites had selectivity between these two. The functionality of the model was successfully verified by modeling the Cs sorption isotherms on crushed mica gneiss rock in saline groundwater. Determination of the exchangeable ions K, Na, Ca, and Cs on the basal plane and edge surfaces by scanning electron microscopy-energy-dispersive x-ray spectroscopy (SEM-EDX) supports the results of modeling: edge sites highly prefer Cs ions and also Ca and Na ions but not K ions.

  14. Development of hexacyanoferrate complex on the absorbent matrix (Amberlite XAD-4) for the removal of cesium from neutral and acidic waste streams in reproceesing plants (Paper No. AL-43)

    International Nuclear Information System (INIS)

    The important role of support material on the performance of K2MFe(CN)6(M is the transition metal with oxidation state II) ion exchanger for selective absorption of cesium is described in this paper. The material erosion and chemical decomposition have been overcome using macroporous absorbent type resin. (author)

  15. Modeling of the sorptive behavior of a clay material used as reactive barrier for cesium migration in Huelva (Spain)

    International Nuclear Information System (INIS)

    Document available in extended abstract form only. On 1998 a 137Cs source was accidentally molten in the installations of a Spanish company of stainless steel production. Not being aware of the contamination with Cs, the produced powder was treated in an inert plant and these inert materials were normally used as filling material to restore phosphogypsum piles. The contaminated material ended up in the phosphogypsum piles at the Center of Inert Recuperation (CRI), located at the salt marshes of Huelva (Spain). This is a large extension oriented towards the sea with marsh vegetation subject to the tide. Since the cesium contamination was discovered, this zone has been thoroughly analyzed in order to evaluate the radiological impact of the presence of cesium and the possible contamination of soils and water in the surrounding. Recently, in two different locations at CRI, permeable reactive barriers were constructed to retard cesium migration. The main component of these barriers is a clay material called Rojo Carbonero (RC), whose properties as cesium sorbent have to be analyzed in depth. This material is mainly formed by: quartz (27%), phyllosilicates (58%), dolomite (8%), feldspar (2%), hematite (5%). The clayey fraction (<2 μm) is composed by a 98% of illite and the rest is chlorite/kaolinite. Different studies were carried out to quantify the sorption of cesium in this material previous to the construction of the reactive barriers. Due to the large variability of the chemical composition of the waters at the site a significant variability of sorption values, in terms of distribution coefficients (Kd) was also observed. In order to predict the migration of cesium in these barriers, taking into account this variability and the presence of competing ions, a detailed experimental study was carried out with the aim of determining the selectivity coefficients of cesium with respect to the main ions present in the water. Basically, the material was converted in

  16. Formation of negative ions on a metal surface

    International Nuclear Information System (INIS)

    In this thesis a fundamental study of the charge exchange process of positive ions on the converter surface is presented. Beams of hydrogen ad cesium ions are scattered from a thoroughly cleaned W(110) surface, under ultra-high vacuum conditions. The cesium coverage of the surface is a controlled parameter. Ch. 2 deals with the negative-ion formation probability for hydrogen atoms. The influence of coabsorption of hydrogen is studied in Ch. 3. These measurements are important for understanding the formation process in plasma sources, because the converter surface is expected to be strongly contaminated with hydrogen. The charge state of scattered cesium particles is investigated in Ch. 4. Knowledge of this parameter is essential for Ch. 5, in which a model study of adsorption of cesium on a metal surface in contact with a plasma is presented. Finally, the negative-ion formation process in a plasma environment is studied in Ch. 6. Measurements done on a hollow-cathode discharge equipped with a novel type of converter, a porous tungsten button, are discussed. Liquid cesium diffuses through this button towards the side in contact with the plasma. (Auth.)

  17. Strategic Design and Optimization of Inorganic Sorbents for Cesium, Strontium and Actinides

    Energy Technology Data Exchange (ETDEWEB)

    Edward J. Maginn

    2009-11-09

    The primary objective of the Notre Dame component of the project was computational in nature. The goal was to provide a design tool for the synthesis of optimized sorbents for the removal of cesium, strontium and actinides from nuclear waste solutions. Molecular modeling enables us to observe and better understand the molecular level interactions that govern the selectivity of specific radionuclides in a particular sorbent. The research focused on the development and validation of a suitable and transferable model for all the cations and ion exchangers of interest, nd then subsequent simulations which determined the siting and mobility of water and cations. Speciic accomplishments include: (1) improving existing intermolecular force fields to accurately model the sorbents of interest; (2) utilizing energy-minimizations and molecular dynamics simulations for structural prediction of CST and niobium-substituted CST materials; (3) determining Na+/water positions in polyoxoniobate materials using molecular dynamics simulations; and (4) developing Hybrid Monte Carlo methods for improved structural prediction.

  18. Electrokinetic decontamination of porous media. Experimental study and modeling of the cesium transport through cementitious materials

    International Nuclear Information System (INIS)

    The aim of this work is to study the nuclear decontamination of cementitious materials by an electrokinetic method. Special attention is given to the understanding of the mechanisms leading to the removal of radioelements from the material. First, a bibliographic research allowed us to reduce the study to a normalized mortar and to cesium ions. This choice was confirmed by the experimental study of interactions between the contaminant and the material. Next, the efficiency of the electrokinetic decontamination was experimentally shown in laboratory conditions and electromigration was identified as the main transport phenomenon. Then, a numerical model was implemented in order to describe the ionic transport by electromigration. The results obtained were compared to experiments. Finally, some applications and developments of the electrokinetic process were proposed. (author)

  19. Metabolism of {sup 137}cesium, {sup 137}barium in the rat. Therapeutics of the contamination; Metabolisme du {sup 137}cesium, {sup 137}baryum chez le rat. Therapeutique de la contamination

    Energy Technology Data Exchange (ETDEWEB)

    Remy, J.; Philippon, A.; Lafuma, J.; Walter, C. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires. Departement de la Protection Sanitaire, Laboratoire de Radiopathologie

    1967-07-01

    The authors carry out research into the distribution kinetics, the metabolism and the excretion of {sup 137}Cs - {sup 137}Ba in the rat. They show that these phenomena are independent of the method of applying a single dose. The distribution tends to adopt in all cases a typical shape which remains the same depending on the body burden. Biological analysis of the state of the cesium in the biological media shows that it is transported in the free and ionised form. Considering the problem of the method of penetration of the cesium ion in the intracellular medium, and in particular by the in vivo and in vitro kinetic study of the plasma - red cell system, the authors make the assumption that an active transport of cesium occurs by the cell membrane. They thus arrive at an overall picture of the cesium distribution in the organism which is essentially characterized by a dynamic distribution equilibrium between two compartments: 99 per cent of the cesium accumulates in the intracellular pool, 1 per cent in the extracellular liquids. This latter compartment is open to the emunctories. Because, of the active transport by the cell membranes, the intracellular pool is filled rapidly but discharge is slow. This phenomenon is the limiting factor in the decrease of the body burden. From this representation, the authors deduce the reasons for the relative failure of the various therapeutic methods examined up till now by themselves or by other authors. The stimulation of the natural emunctories in the case of diuretics for example, can only improve the purification of the extracellular compartment. Now this latter contains only 1 per cent of the body burden and recharging is slow. Furthermore the methods designed to counteract or inhibit the active transport of cesium by the cell membrane are still at the present time incompatible with the survival of the cell. (authors) [French] Les auteurs etudient experimentalement la cinetique de distribution, le metabolisme et l

  20. A biglycolamide substituted Calix-benzo-crown-6 in 1,3-alternate conformation: selective ditopic ionophore for Cesium (I) and Uranium (VI) extraction

    International Nuclear Information System (INIS)

    A new substituted calix-benzo-crown-6 biglycolamide (CBCDGA) ionophore in 1,3-alternate conformation has been synthesized and characterized by using 1H NMR and MALDI-TOF. The 1H NMR peak at δ 3.74 corresponds to bridge methylene group of (s, 8H,-4ArCH2Ar) 1,3 alternate conformation of calix-crown. MALDI-TOF showed m/z 1151.02, 1166.99 (M+ Na+, M+ K+), it confirms the molecular weight of CBCBGA. Extraction properties of CBCBGA towards cesium and other metal ions present in HLW were investigated from nitric acid medium. This ionophore is serving as a highly selective ditopic receptor for cesium and uranium over other metal ions present in the simulated high level liquid waste solution. Extraction of cesium is accredited by the complementarity of crown cavity and the uranium by suitably spaced glycolamide groups present in the 1,3-alternate positions of calix-crown. The solvent composition of 0.01 M CBCBGA in o-Nitro phenyl hexyl ether(o-NPHE) showed DCs and DU of 12.5 and 1.5 respectively from 3.2 M nitric acid solution. The other metal ions present (Am, Mo, Ru, Sr, Ce, Pd, Na, Ba) in the waste have shown almost no extraction

  1. A method for reducing the cesium-137 content in meat

    International Nuclear Information System (INIS)

    Reports a study of a method for reducing the amount of cesium-137 in meat from wild animals. The method is intended for use in the kitchen and is based on a combined leaching and mechanical process. (K.A.E.)

  2. Cesium-137 Levels Detected in Otters from Austria

    Directory of Open Access Journals (Sweden)

    Gutleb A.C.

    1991-02-01

    Full Text Available Pollution seems to be one of the most important causes for the decline of the European otter (Lutra lutra. The accident in the Chernobyl nuclear power plant added another aspect to environmental pollution. Few data on cesium-137 contents in otters are available, so levels were measured in 3 otters from Austria. All levels found were very low.

  3. Fission-product tellurium and cesium telluride chemistry revisited

    International Nuclear Information System (INIS)

    The chemistry of fission-product tellurium is discussed with a focus on conditions in an operating CANDU reactor and in an accident scenario, i.e., a loss of coolant accident (LOCA). Cesium telluride, Cs2Te, is likely to be one of the most abundant tellurium species released to containment. Available thermodynamic data on gas phase Cs2Te is not complete; hence the volatility of cesium telluride was studied by Knudsen-cell mass spectrometry. Cesium telluride was found to vapourize incongruently, becoming more tellurium-rich in the condensed phase as vapourization progressed. Vapour-phase species that were observed were elemental cesium and tellurium, CsTe, Cs2Te, Cs2Te2 and Cs2Te3. Second-law enthalpies and entropies were obtained for many of these species, and a third-law value, ΔH298o, of 186 ± 2 kJ·mol-1 was obtained for Cs2Te. (author)

  4. Discovery of Cesium, Lanthanum, Praseodymium and Promethium Isotopes

    OpenAIRE

    May, E.; Thoennessen, M

    2011-01-01

    Currently, forty-one cesium, thirty-five lanthanum, thirty-two praseodymium, and thirty-one promethium, isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  5. Strontium-90 and cesium-137 in fresh water

    International Nuclear Information System (INIS)

    Japan Chemical Analysis Center has analysed the strontium-90 and Cesium-137 contents in fresh water from 7 prefectures in Japan by the commission of Science and Technology Agency of Japanese Government. The method described in ''Radioactivity Survey Data in Japan No. 43 (NIRS-RSD-43, 1977) was applied to the analysis of these two radionuclides in samples. (author)

  6. Membrane-based separation technologies for cesium, strontium, and technetium

    Energy Technology Data Exchange (ETDEWEB)

    Kafka, T.

    1996-10-01

    This work is one of two parallel projects that are part of an ESP task to develop high-capacity, selective, solid extractants for cesium, strontium, and technetium from nuclear wastes. In this subtask, Pacific Northwest National Laboratory (PNNL) is collaborating with 3M, St. Paul, Minnesota, working in cooperation with IBC Advanced Technologies, American Fork, Utah.

  7. Cesium-137 Levels Detected in Otters from Austria

    OpenAIRE

    Gutleb A.C.; Mraz, G.

    1991-01-01

    Pollution seems to be one of the most important causes for the decline of the European otter (Lutra lutra). The accident in the Chernobyl nuclear power plant added another aspect to environmental pollution. Few data on cesium-137 contents in otters are available, so levels were measured in 3 otters from Austria. All levels found were very low.

  8. Selective extraction of cesium: from compound to process

    International Nuclear Information System (INIS)

    Under the French law of 30 December 1991 on nuclear waste management, research is conducted to recover long-lived fission products from high-level radioactive effluents generated by spent fuel reprocessing, in order to destroy them by transmutation or encapsulate them in specific matrices. Cesium extraction with mono and bis-crown calix(4)arenes (Frame 1) is a candidate for process development. These extractants remove cesium from highly acidic or basic pH media even with high salinity. A real raffinate was treated in 1994 in a hot cell to extract cesium with a calix-crown extractant. The success of this one batch experiment confirmed the feasibility of cesium decontamination from high-level liquid waste. It was then decided to develop a process flowchart to extract cesium selectively from high-level raffinate, to be included in the general scheme of long-lived radionuclide partitioning. It was accordingly decided to develop a process based on liquid-liquid extraction and hence optimize a calixarene/diluent solvent according to: - hydraulic properties: density, viscosity, interfacial tension, - chemical criteria: sufficient cesium extraction (depending on the diluent), kinetics, third phase elimination... New mono-crown-calixarenes branched with long aliphatic groups (Frame 2) were designed to be soluble in aliphatic diluents. To prevent third phase formation associated with nitric acid extraction, the addition of modifiers (alcohol, phosphate and amide) in the organic phase was tested (Frame 3). Table 1 shows examples of calixarene/diluent systems suitable for a process flowchart, and Figure 2 provides data on cesium extraction with these new systems. Alongside these improvements, a system based on a modified 1,3-di(n-octyl-oxy)2,4-calix[4]arene crown and a modified diluent was also developed, considering a mixed TPH/NPHE system as the diluent, where TPH (hydrogenated tetra propylene) is a common aliphatic industrial solvent and NPHE is nitrophenyl

  9. Demonstration test for decontamination technology of cesium-contaminated ash

    International Nuclear Information System (INIS)

    KEPCO Engineering and Construction Company (KEPCO E and C), architecture and engineering company of nuclear power plant, developed the 'decontamination technology of cesium-contaminated ash' in the basis of pre-owned 'decontamination technology of cesium-contaminated soil'. The new technology was demonstrated in Fukushima prefecture during 12 days from November 5, 2013, in order to verify the performance. Demonstration equipment (CEDECON-DA), with a capacity of treatment of 20 ℓ per batch, can be carried in a container in order to promote the ease of transportation and in-situ installation. Through the demonstration test it was verified the superior performance and the possibility of commercialization. This technique comprises of cesium separation and cesium coagulation processes. Briefly speaking, the principal of this process is as follows; cesium is separated from ash, detached to the coagulation and then deposited. The decontaminated ash can be disposed of into municipal landfills as conventional non-radioactive waste. The present technology is evaluated such that the disposal amount of radioactive waste will be significantly reduced. The ash with average concentration of 6,200 Bq/kg from a conventional incineration plant was used for the demonstration test. Each separate performance test has been carried out under acid, neutral and alkaline conditions, respectively. The test result for alkaline condition showed the highest decontamination ratio of 82-85% and the volume reduction ratio of 95%. Radioactive Waste Management and Nuclear Facility Decommissioning Technology Center (RANDEC) performed the radiation protection management, activity measurement and evaluation in the demonstration test results. (author)

  10. Some aspects of cesium deposition in Transilvania (Romania)

    International Nuclear Information System (INIS)

    Following the accident of the Chernobyl atomic electric power station, a great quantity of radionuclides (∼100MCi) escaped from the reactor. It was estimated that 13% of the inventory activity of cesium representing 1.5-2 MCi left the reactor. The radioactive deposits were very nonuniform for the same distance and in the same direction from Chernobyl nuclear center having a close dependence upon direction and speed of wind and pluviometric conditions. The rains, especially the storms, spectacularly increased the radioactive fallout. Although, for the first two-three days, subsequent to accident, the meteorological conditions were favorable for Romania, after April 29/30, because of the changing in the wind direction on SW (initial it was N and NW) the countries were on this direction - Romania, Bulgaria, Greece, former Yugoslavia - began to be intensely contaminated with radioactive fallout. In Romania, the radioactive cloud passing coincided with abundant rains, especially on the direction mentioned above. On this direction, the cesium deposits are of 8-2 times larger than other Romanian regions. The torrential rain which fell on May 1st 1986, in the western side of Cluj Napoca town caused an intense contamination especially with short-life isotopes as Te, I, Ba, La, Mo. Medium and long-life isotopes as Ru, Zr, Cs, Sr were present in large quantities in this area.too. For the total contribution the value obtained was 1130 kBq/m2, much larger than the average in Romania. This work presents data about cesium content of pollen samples gathered daily between 1-30 May 1986; cesium deposits in five areas and some measurements in connection with cesium mitigation in soils

  11. Electrochemical assessment of water|ionic liquid biphasic systems towards cesium extraction from nuclear waste

    International Nuclear Information System (INIS)

    Highlights: • Electroanalytical chemistry was employed to assess cesium ion extraction in biphasic systems. • Water|ionic liquid systems are much more efficient than traditional water|organic ones. • The metal ion to ligand stoichiometry and overall complexation constant were determined. • The stoichiometry was confirmed by mass spectrometry. • The ligand CMPO used in TRUEX processes was found to be effective for the FIT. - Abstract: A room temperature ionic liquid (IL) composed of a quaternary alkylphosphonium (trihexyltetradecylphosphonium, P66614+) and tetrakis(pentafluorophenyl)borate anion (TB−) was employed within a water|P66614TB (w|P66614TB or w|IL) biphasic system to evaluate cesium ion extraction in comparison to that with a traditional water|organic solvent (w|o) combination. 137Cs is a major contributor to the radioactivity of spent nuclear fuel as it leaves the reactor, and its extraction efficiency is therefore of considerable importance. The extraction was facilitated by the ligand octyl(phenyl)-N,N′-diisobutylcarbamoylphosphine oxide (CMPO) used in TRans-Uranium EXtraction processes and investigated through well established liquid|liquid electrochemistry. This study gave access to the metal ion to ligand (1:n) stoichiometry and overall complexation constant, β, of the interfacial complexation reaction which were determined to be 1:3 and 1.6 × 1011 at the w|P66614TB interface while the study at w|o elicited an n equal to 1 with β equal to 86.5. Through a straightforward relationship, these complexation constant values were converted to distribution coefficients, δα, with the ligand concentrations studied for comparison to other studies present in the literature; the w|o and w|IL systems gave δα of 2 and 8.2 × 107, respectively, indicating a higher overall extraction efficiency for the latter. For the w|o system, the metal ion-ligand stoichiometries were confirmed through isotopic distribution analysis of mass spectra obtained by

  12. Electrochemical assessment of water|ionic liquid biphasic systems towards cesium extraction from nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Stockmann, T. Jane [Laboratoire d’Electrochimie Physique et Analytique, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 6, Lausanne CH-1015 (Switzerland); Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7 (Canada); Zhang, Jing; Montgomery, Anne-Marie [Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7 (Canada); Ding, Zhifeng, E-mail: zfding@uwo.ca [Department of Chemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 5B7 (Canada)

    2014-04-01

    Highlights: • Electroanalytical chemistry was employed to assess cesium ion extraction in biphasic systems. • Water|ionic liquid systems are much more efficient than traditional water|organic ones. • The metal ion to ligand stoichiometry and overall complexation constant were determined. • The stoichiometry was confirmed by mass spectrometry. • The ligand CMPO used in TRUEX processes was found to be effective for the FIT. Abstract: A room temperature ionic liquid (IL) composed of a quaternary alkylphosphonium (trihexyltetradecylphosphonium, P66614⁺) and tetrakis(pentafluorophenyl)borate anion (TB⁻) was employed within a water|P66614TB (w|P66614TB or w|IL) biphasic system to evaluate cesium ion extraction in comparison to that with a traditional water|organic solvent (w|o) combination. ¹³⁷Cs is a major contributor to the radioactivity of spent nuclear fuel as it leaves the reactor, and its extraction efficiency is therefore of considerable importance. The extraction was facilitated by the ligand octyl(phenyl)-N,N'-diisobutylcarbamoylphosphine oxide (CMPO) used in TRans-Uranium EXtraction processes and investigated through well established liquid|liquid electrochemistry. This study gave access to the metal ion to ligand (1:n) stoichiometry and overall complexation constant, β, of the interfacial complexation reaction which were determined to be 1:3 and 1.6 × 10¹¹ at the w|P66614TB interface while the study at w|o elicited an n equal to 1 with β equal to 86.5. Through a straightforward relationship, these complexation constant values were converted to distribution coefficients, δα, with the ligand concentrations studied for comparison to other studies present in the literature; the w|o and w|IL systems gave δα of 2 and 8.2 × 10⁷, respectively, indicating a higher overall extraction efficiency for the latter. For the w|o system, the metal ion-ligand stoichiometries were

  13. Distribution and retention of cesium and strontium in Swedish boreal forest ecosystems

    International Nuclear Information System (INIS)

    The retention and distribution of cesium, and to some extent strontium, in forest environments are being studied at three sites in Sweden. The main part of the cesium found in the soil was recovered in horizons rich in organic matter. The cesium was retained in the soil organic matter in a more or less extractable form. As different soil types have a different distribution pattern of organic matter, the distribution of cesium will depend on the forest soil type. The clay content in Swedish forest soils is, in general, low which will mitigate the retention of cesium in the soil mineral horizons. The cesium and strontium present in the trees was considered to be an effect of assimilation by the tissues in the canopy as well as by the roots. The redistribution of cesium within the trees was extensive which was considered to be the effect of a high mobility of cesium in the trees. The recovery of strontium-90 in pines, in relation to the deposition rate was higher compared to the relative recovery of cesium-137, 30 years after deposition. The cesium and strontium will remain in the forest environment for a considerable time but can be reduced by forest practice, by leaching out of the soil profile or by radioactive decay

  14. Sorption behavior of cesium on Ain Oussera soil under different physicochemical conditions

    International Nuclear Information System (INIS)

    In the present study, the sorption behavior of cesium was investigated in Ain Oussera soil around the Es-Salam reactor facility. This study was conducted using batch method under different physicochemical conditions including contact time, ionic strength, pH, solid/liquid ratio and temperature. The results showed that sorption followed pseudo-second-order kinetics with a good regression coefficients (R2 = 0.999). The activation energies were 11.26 and 15.21 kJ mol-1 which correspond to ion-exchange-type sorption mechanism. The adsorption was favored at low temperature and it was exothermic (ΔH0 -1) and spontaneous (ΔG0 -1 at 23 deg. C and -13.2 kJ mol-1 at 60 deg. C). The presence of competing cations such as K+ and Ca2+ ions in groundwater can significantly reduce the Cs adsorption onto soil. Desorption reaction was also investigated using three reagents with different ionic strengths (deionized water, groundwater and 0.1 M KCl solution). The results showed that Cs ions were preferentially distributed onto high affinity sorption sites.

  15. Sorption behavior of cesium on Ain Oussera soil under different physicochemical conditions.

    Science.gov (United States)

    Bouzidi, A; Souahi, F; Hanini, S

    2010-12-15

    In the present study, the sorption behavior of cesium was investigated in Ain Oussera soil around the Es-Salam reactor facility. This study was conducted using batch method under different physicochemical conditions including contact time, ionic strength, pH, solid/liquid ratio and temperature. The results showed that sorption followed pseudo-second-order kinetics with a good regression coefficients (R(2)=0.999). The activation energies were 11.26 and 15.21 kJ mol(-1) which correspond to ion-exchange-type sorption mechanism. The adsorption was favored at low temperature and it was exothermic (ΔH(0)<0, with average value of -1.97 kJ mol(-1)) and spontaneous (ΔG(0)<0, with average value of -11.97 kJ mol(-1) at 23°C and -13.2 kJ mol(-1) at 60°C). The presence of competing cations such as K(+) and Ca(2+) ions in groundwater can significantly reduce the Cs adsorption onto soil. Desorption reaction was also investigated using three reagents with different ionic strengths (deionized water, groundwater and 0.1M KCl solution). The results showed that Cs ions were preferentially distributed onto high affinity sorption sites. PMID:20869168

  16. Sorption behavior of cesium on Ain Oussera soil under different physicochemical conditions

    Energy Technology Data Exchange (ETDEWEB)

    Bouzidi, A., E-mail: bouzidiaek@yahoo.fr [Centre de Recherche Nucleaire de Birine, 17200 Ain Oussera (Algeria); Souahi, F. [Ecole Nationale Polytechnique, El Harrach, Algiers (Algeria); Hanini, S. [Universite Yahia Fares, 26000 Media (Algeria)

    2010-12-15

    In the present study, the sorption behavior of cesium was investigated in Ain Oussera soil around the Es-Salam reactor facility. This study was conducted using batch method under different physicochemical conditions including contact time, ionic strength, pH, solid/liquid ratio and temperature. The results showed that sorption followed pseudo-second-order kinetics with a good regression coefficients (R{sup 2} = 0.999). The activation energies were 11.26 and 15.21 kJ mol{sup -1} which correspond to ion-exchange-type sorption mechanism. The adsorption was favored at low temperature and it was exothermic ({Delta}H{sup 0} < 0, with average value of -1.97 kJ mol{sup -1}) and spontaneous ({Delta}G{sup 0} < 0, with average value of -11.97 kJ mol{sup -1} at 23 deg. C and -13.2 kJ mol{sup -1} at 60 deg. C). The presence of competing cations such as K{sup +} and Ca{sup 2+} ions in groundwater can significantly reduce the Cs adsorption onto soil. Desorption reaction was also investigated using three reagents with different ionic strengths (deionized water, groundwater and 0.1 M KCl solution). The results showed that Cs ions were preferentially distributed onto high affinity sorption sites.

  17. Efficient removal of cesium from low-level radioactive liquid waste using natural and impregnated zeolite minerals

    International Nuclear Information System (INIS)

    The objective of the proposed work was focused to provide promising solid-phase materials that combine relatively inexpensive and high removal capacity of some radionuclides from low-level radioactive liquid waste (LLRLW). Four various zeolite minerals including natural clinoptilolite (NaNCl), natural chabazite (NaNCh), natural mordenite (NaNM) and synthetic mordenite (NaSM) were investigated. The effective key parameters on the sorption behavior of cesium (Cs-134) were investigated using batch equilibrium technique with respect to the waste solution pH, contacting time, potassium ion concentration, waste solution volume/sorbent weight ratio and Cs ion concentration. The obtained results revealed that natural chabazite (NaNCh) has the higher distribution coefficients and capacity towards Cs ion rather than the other investigated zeolite materials. Furthermore, novel impregnated zeolite material (ISM) was prepared by loading Calix [4] arene bis(-2,3 naphtho-crown-6) onto synthetic mordenite to combine the high removal uptake of the mordenite with the high selectivity of Calix [4] arene towards Cs radionuclide. Comparing the obtained results for both NaSM and the impregnated synthetic mordenite (ISM-25), it could be observed that the impregnation process leads to high improvement in the distribution coefficients of Cs+ ion (from 0.52 to 27.63 L/g). The final objective in all cases was aimed at determining feasible and economically reliable solution to the management of LLRLW specifically for the problems related to the low decontamination factor and the effective recovery of monovalent cesium ion.

  18. Precision lifetime measurement of the cesium $6P_{3/2}$ level using ultrafast pump-probe laser pulses

    CERN Document Server

    Patterson, Brian M; Ehrenreich, Thomas; Gearba, Mirela A; Brooke, George M; Scoville, James; Knize, Randy J

    2014-01-01

    Using the inherent timing stability of pulses from a mode-locked laser, we have precisely measured the cesium $6P_{3/2}$ excited state lifetime. An initial pump pulse excites cesium atoms in two counter-propagating atomic beams to the $6P_{3/2}$ level. A subsequent synchronized probe pulse ionizes atoms which remain in the excited state, and the photo-ions are collected and counted. By selecting pump pulses which vary in time with respect to the probe pulses, we obtain a sampling of the excited state population in time, resulting in a lifetime value of 30.462(46) ns. The measurement uncertainty (0.15%) is larger than our previous report of 0.12% [Phys. Rev. A 84, 010501(R) (2011)] due to the inclusion of additional data and systematic errors. In this follow-up paper we present details of the primary systematic errors encountered in the measurement, which include atomic motion within the intensity profiles of the laser beams, quantum beating in the photo-ion signal, and radiation trapping. Improvements to furt...

  19. Spectrally selective optical pumping in Doppler-broadened cesium atoms

    International Nuclear Information System (INIS)

    The D1 line spectrally selective pumping process in Doppler-broadened cesium is analyzed by solving the optical Bloch equations. The process, described by a three-level model with the Λ scheme, shows that the saturation intensity of broadened atoms is three orders of magnitude larger than that of resting atoms. The |Fg = 3> → |Fe = 4> resonance pumping can result in the ground state |Fg = 4, mF = 4> sublevel having a maximum population of 0.157 and the population difference would be about 0.01 in two adjacent magnetic sublevels of the hyperfine (HF) state Fg = 4. To enhance the anisotropy in the ground state, we suggest employing dichromatic optical HF pumping by adding a laser to excite D1 line |Fg = 4> → |Fe = 3> transition, in which the cesium magnetometer sensitivity increases by half a magnitude and is unaffected by the nonlinear Zeeman effect even in Earth's average magnetic field. (atomic and molecular physics)

  20. Trapping and cooling cesium atoms in a speckle field

    International Nuclear Information System (INIS)

    We present the results of two experiments where cold cesium atoms are trapped in a speckle field. In the first experiment, a YAG laser creates the speckle pattern and induces a far-detuned dipole potential which is a nearly-conservative potential. Localization of atoms near the intensity maxima of the speckle field is observed. In a second experiment we use two counterpropagating laser beams tuned close to a resonance line of cesium and in the lin perpendicular to lin configuration, one of them being modulated by a holographic diffuser that creates the speckle field. Three-dimensional cooling is observed. Variations of the temperature and of the spatial diffusion coefficient with the size of a speckle grain are presented. (orig.)

  1. Kelvin Probe Studies of Cesium Telluride Photocathode for AWA Photoinjector

    CERN Document Server

    Wisniewski, Eric; Yusof, Zikri; Spentzouris, Linda; Terry, Jeff; Harkay, Katherine

    2012-01-01

    Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch (~50 nC) in a long bunch train. Here, we present a study of the work function of cesium telluride photocathode using the Kelvin Probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the effect of UV exposure on the work function, and the evolution of the work function during and after photocathode rejuvenation via heating.

  2. Strontium-90 and cesium-137 in air-borne dust

    International Nuclear Information System (INIS)

    Under the commission of Science and Technology Agency, Japan Chemical Analysis Center and prefectural public health laboratories and institutes have determined the levels of strontium-90 and cesium-137 in air-borne dust samples. Dust samples were collected by the aspiration of 3000 m3 or more air at 1.0 -- 1.5 m above the ground surface in 10 prefectural public health laboratories and institutes. The samples collected during three months were combined, and were forwarded to Japan Chemical Analysis Center after carbonization. These samples were ashed in an electric muffle furnance at Japan Chemical Analysis Center. The ash to which both some carriers and hydrochloric acid were added, was destroyed under heating. The solution was dissolved into hydrochloric and filtered, after it was added with nitric acid and heated to dryness. The filtrate was radiochemically analysed for strontium-90 and cesium-137 with low background beta-ray spectrometer. (author)

  3. Cesium and lead uptake by CSH phases of hydrated cement

    International Nuclear Information System (INIS)

    As Kd from radwaste elements in concrete systems show a wide range of values, a modelling of cesium and lead immobilization in Calcium Silicate Hydrate (CSH, xCaO.SiO2.H2O, with 0.7 (aged cements)SiOH) and precipitation equilibria. Values of Kd from cesium and lead in CSH matrix can thus be calculated with Ca/Si evolution and ionic strength effect. Predictive calculations have been carried out with success with different Ca/Si ratios, ionic strengths and liquid/solid ratios, and results are well superimposed with experimental isotherm data. If the CSH really allow accounting for the radwaste behavior in hydrated cement matrices, this model can be used in safety assessment calculations, with varying pH and [Ca2+] as cement degradation state parameters. Copyright (2001) Material Research Society

  4. New thermodynamic regularity for cesium over the whole liquid range

    CERN Document Server

    Ghatee, M H

    2001-01-01

    In this paper we derive an equation of state for liquid cesium based on a suggested potential function in accord to the characteristics large attraction and soft repulsion at the asymptotes of interaction potentials. By considering the interaction of nearest adjacent atoms in dense fluid, the equation of state predicts that the isotherm is linear function of, where is the compression factor, is the molar volume, and is the molar density. The linear parameters are identified as interaction coefficients related to attraction and repulsion, and are used to evaluate the molecular parameters with interesting implications. The isotherm is intended to resolve the particular thermodynamic properties of alkali metals, which have been known for their unusual change of the nature of intermolecular force as the characteristic metal-nonmetal transition range is approached. When applied to liquid cesium, the isotherms persist linear over the whole liquid range including the metal non-metals transition range and at the crit...

  5. Strontium-90 and cesium-137 in air-borne dust

    International Nuclear Information System (INIS)

    The levels of strontium-90 and cesium-137 in airborne dust have been determined by Japan Chemical Analysis Center under the contact with Science and Technology Agency. Dust samples were collected at 1.0 -- 1.5m above the ground surface with electrostatic precipitators or on filter papers by each prefectural public health laboratories and institutes in 9 prefectures, and these samples were forwarded to Japan Chemical Analysis Center after the carbonization. These samples were asked in an electric muffle furnance at Japan Chemical Analysis Center. The ask to which both some carriers and hydrochloric acid were added, was destroyed under heating. The solution was dissolved into hydrochloric acid and filtered, after it was added with nitric acid and heated to dryness. The filtrate was analysed for strontium-90 and cesium-137 using the method recommended by science and Technology Agency. (author)

  6. Cesium-137, a drama recounted; Cesio-137, um drama recontado

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Suzane de Alencar

    2013-01-15

    The radiological accident with Cesium-137, which started on Goiania in 1987, did not stop with the end of radiological contamination and continues in a judicial, scientific and narrative process of identification and recognition of new victims. The drama occupies a central place on the dynamics of radiological event, as it extends its limits, inflects its intensity and updates the event. As a narrative of the event, the ethnography incorporates and brings up to date the drama as an analysis landmark and the description of the theme as it is absorbed by a dramatic process. Cesium-137, a drama recounted is a textual experimentation based on real events and characters picked out from statements reported in various narratives about the radiological accident. (author)

  7. Preliminary results from uranium/americium affinity studies under experimental conditions for cesium removal from NPP ''Kozloduy'' simulated wastes solutions

    International Nuclear Information System (INIS)

    We use the approach described by Westinghouse Savannah River Company using ammonium molybdophosphate (AMP) to remove elevated concentrations of radioactive cesium to facilitate handling waste samples from NPP Kozloduy. Preliminary series of tests were carried out to determine the exact conditions for sufficient cesium removal from five simulated waste solutions with concentrations of compounds, whose complexing power complicates any subsequent processing. Simulated wastes solutions contain high concentrations of nitrates, borates, H2C2O4, ethylenediaminetetraacetate (EDTA) and Citric acid, according to the composition of the real waste from the NPP. On this basis a laboratory treatment protocol was created. This experiment is a preparation for the analysis of real waste samples. In this sense the results are preliminary. Unwanted removal of non-cesium radioactive species from simulated waste solutions was studied with gamma spectrometry with the aim to find a compromise between on the one hand the AMP effectiveness and on the other hand unwanted affinity to AMP of Uranium and Americium. Success for the treatment protocol is defined by proving minimal uptake of U and Am, while at the same time demonstrating good removal effectiveness through the use of AMP. Uptake of U and Am were determined as influenced by oxidizing agents at nitric acid concentrations, proposed by Savannah River National laboratory. It was found that AMP does not significantly remove U and Am when concentration of oxidizing agents is more than 0.1M for simulated waste solutions and for contact times inherent in laboratory treatment protocol. Uranium and Americium affinity under experimental conditions for cesium removal were evaluated from gamma spectrometric data. Results are given for the model experiment and an approach for the real waste analysis is chosen. Under our experimental conditions simulated wastes solutions showed minimal affinity to AMP when U and Am are most probably in the

  8. Batch sorption experiments with iodine, bromine, strontium, sodium and cesium on Grimsel mylonite

    International Nuclear Information System (INIS)

    Promylonite surrounding the fracture at the migration site was not available in sufficient amounts, so mylonite from an adjacent fault zone was used. All the work has been carried out in glove boxes in a nitrogen atmosphere with very low O2 and CO2 levels. Mylonite was equilibrated with the natural Grimsel groundwater (NGW) prior to sorption experiments. The first series of sorption experiments was carried out without shaking. This caused sedimentation of the mylonite and led to slow kinetics. In the later experiments therefore, gentle, continuous agitation was used. No sorption of iodine and bromine on mylonite was observed under the experimental conditions used. It was observed that the sorption coefficient of 85Sr and 22Na were not affected by varying nuclide concentrations, provided these were kept much below their natural levels in NGW. This indicates that, in this nuclide concentration range, isotopic exchange takes place. Sorption coefficients did not vary with the rock/water ratio. Experiments with a bulky displacing cation suggested that some sodium ions were on less accessible internal sites and this could account for the slow kinetics for sodium. Further experiments with samples with smaller particle size confirmed this hypothesis. Batch sorption experiments on mylonite at initial cesium concentrations of between 3,2.10-8 and 5,0.10-4 M showed that sorption was reversible and non-linear; sorption coefficients were between 3800 and 21 ml/g. Increasing the potassium concentration in the solution led to reduced sorption of cesium, suggesting that Cs and K compete for the sorption sites. At the lowest Cs concentration used, sorption appears to be due to exchange with K at specific sites on mica, together with possible isotopic exchange. For these conditions and by making some assumptions, a Cs sorption coefficient for waters with different concentrations could be estimated. (author) 7 figs., 12 tabs., 42 refs

  9. Radioactive cesium. Dynamics and transport in forestal food-webs

    International Nuclear Information System (INIS)

    This report summarises results from a radioecological study during 1994-1995 concerning turnover, redistribution and loss of radioactive Cesium (134 and 137) in boreal forest ecosystems, as well as uptake and transfer in important food-chains over moose, vole and vegetation. The basis for this report are 9 publications published 1994-95. These reports are presented in summary form. 9 refs, 17 figs

  10. Optimized production of a cesium Bose-Einstein condensate

    OpenAIRE

    Kraemer, Tobias; Herbig, Jens; Mark, Michael; Weber, Tino; Chin, Cheng; Naegerl, Hanns-Christoph; Grimm, Rudolf

    2004-01-01

    We report on the optimized production of a Bose-Einstein condensate of cesium atoms using an optical trapping approach. Based on an improved trap loading and evaporation scheme we obtain more than $10^5$ atoms in the condensed phase. To test the tunability of the interaction in the condensate we study the expansion of the condensate as a function of scattering length. We further excite strong oscillations of the trapped condensate by rapidly varying the interaction strength.

  11. Cesium dihydrophosphate monocrystal growth and certain of their properties

    International Nuclear Information System (INIS)

    Crystals of cesium dihydrophosphate (centrisymmetrical, monoclinic, point symmetric group 2/m) are obtained by methods involving solvent evaporation and temperature reduction. At -122 deg C, a ferroelectric phase transition occurs, and at 230 and 265 deg C first-kind transitions, which are not accompanied by composition changes. CsH2PO4 solubility substantially increases with higher medium acidity, and remains approximately constant in alkali medium

  12. Behaviour of radioactive cesium in northern boreal forest ecosystems

    International Nuclear Information System (INIS)

    Full text: In 1997-2001 a large number of environmental samples have been collected from the Muddusjaervi area in Finnish Lappland. These samples include soil, water, sediment, vegetation and fish samples. Radioactive contamination in this subarctic environment has mainly resulted from the nuclear weapons test fallout in the 1950s and 1960s. Chernobyl accident did not considerably increase the contamination level in this area. The Laboratory of Radiochemistry, University of Helsinki, has been studying the behaviour of fallout radionuclides in the environment and in food chains in Lappland from the beginning of the 1960s. The study area lies in the middle of northern reindeer herding area where accumulation of radioactive cesium has been observed in food chains. In this paper we report on the behaviour of radioactive cesium in soil columns. The soil in this area is typically nutrient-poor podzolic soil. Altogether thirty soil columns were collected and they were divided into horizons (litter, organic and mineral layers). The activity concentrations of the horizons were determined by gamma spectrometry. In general, cesium has been concentrated mainly in the litter and organic layers and it has not been migrated considerably to mineral layers. To study the long term behaviour of cesium in soil the activity concentrations have been compared to those found in earlier decades and to the activity concentrations earlier determined for other radionuclides, especially for Pu. A further major objective was to study runoff of radionuclides from ground to lakes and brooks and therefore many of the soil samples were collected from various distances from lakes and brooks. (author)

  13. Detection of the actinides and cesium from environmental samples

    Science.gov (United States)

    Snow, Mathew Spencer

    Detection of the actinides and cesium in the environment is important for a variety of applications ranging from environmental remediation to safeguards and nuclear forensics. The utilization of multiple different elemental concentrations and isotopic ratios together can significantly improve the ability to attribute contamination to a unique source term and/or generation process; however, the utilization of multiple elemental "signatures" together from environmental samples requires knowledge of the impact of chemical fractionation for various elements under a variety of environmental conditions (including predominantly aqueous versus arid conditions). The research reported in this dissertation focuses on three major areas: 1. Improving the understanding of actinide-mineral interactions at ultra-low concentrations. Chapter 2 reports a batch sorption and modeling study of Np(V) sorption to the mineral goethite from attomolar to micromolar concentrations. 2. Improving the detection capabilities for Thermal Ionization Mass Spectrometry (TIMS) analyses of ultra-trace cesium from environmental samples. Chapter 4 reports a new method which significantly improves the chemical yields, purification, sample processing time, and ultimately, the detection limits for TIMS analyses of femtogram quantities of cesium from a variety of environmental sample matrices. 3. Demonstrating how actinide and cesium concentrations and isotopic ratios from environmental samples can be utilized together to determine a wealth of information including environmental transport mechanisms (e.g. aqueous versus arid transport) and information on the processes which generated the original material. Chapters1, 3 and 5 demonstrate these principles using Pu, Am, Np, and Cs concentrations and isotopic ratios from contaminated soils taken near the Subsurface Disposal Area (SDA) of Idaho National Laboratory (INL) (a low level radioactive waste disposal site in southeastern Idaho).

  14. Corrections to our results for optical nanofiber traps in Cesium

    CERN Document Server

    Ding, D; Choi, K S; Kimble, H J

    2012-01-01

    Several errors in Refs. [1, 2] are corrected related to the optical trapping potentials for a state-insensitive, compensated nanofiber trap for the D2 transition of atomic Cesium. Section I corrects our basic formalism in Ref. [1] for calculating dipole-force potentials. Section II corrects erroneous values for a partial lifetime and a transition wavelength in Ref. [1]. Sections III and IV present corrected figures for various trapping configurations considered in Refs. [1] and [2], respectively.

  15. Method of eluting radioactive nuclide from spent ion exchange resin

    International Nuclear Information System (INIS)

    Highly radioactive spent ion exchange resins containing a great amount of cesium or strontium as radioactive nuclides are immersed in an eluting solution and, by stirring solution, cesium or strontium adsorbed to the spent ion exchange resins are eluted. The eluting solution is passed through a zeolite bed to selectively remove cesium and/or strontium. As an eluent for the eluting solution to be used, sodium salts such as sodium hydroxide or sodium sulfate is preferred. Zeolite having radiation resistance and not suffering from reduction in the absorbent performance by the presence of boric acid or sodium are used. Since the zeolite is highly stabilized with inorganic material by cement or glass solidification, the amount is remarkably reduced as compared with that of the spent resins and the administration is facilitated. (K.M.)

  16. Extraction of rubidium and cesium from micas following sulfate-extraction technology

    International Nuclear Information System (INIS)

    Results are presented of semicommercial tests of procedure of rubidium and cesium extraction from micas. Micas has been processed by the 40% solution of sulphuric acid at boiling temperature. Separate extraction of cesium and rubidium from the solution with arylalkylsubstituted phenol has been conducted after alum crystallization and decomposition by lime. Pure rubidium carbonate and technical cesium carbonate with their 80 and 95% extraction, respectively, are prepared

  17. Investigations of the method of sodium decontamination from cesium and tritium aiming its utilization or disposal

    International Nuclear Information System (INIS)

    Effective methods of removing cesium and tritium from sodium are submitted. It is shown, that the cleaning from cesium with consecutive use of portions of carbon materials will allow on the orders to reduce amount of sorbent, in which is concentrated cesium. For cleaning from tritium technological process with use of a cold trap and special dosage hydrogen in sodium is offered. The data on required time of cleaning and depth of cleaning at various capacity of hydrogen source are given. (author)

  18. Test procedures and instructions for Hanford complexant concentrate supernatant cesium removal using CST

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, D.W.

    1997-01-08

    This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test, using Hanford Complexant Concentrate supernatant liquor from tank 241-AN-107, in a bench-scale column. The cesium sorbent to be tested is crystalline silicotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-023, Hanford Complexant Concentrate Supernatant Cesium Removal Test Plan.

  19. Test procedures and instructions for Hanford tank waste supernatant cesium removal

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, D.W., Westinghouse Hanford

    1996-05-31

    This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test using Hanford Double-Shell Slurry Feed supernatant liquor from tank 251-AW-101 in a bench-scale column.Cesium sorbents to be tested include resorcinol-formaldehyde resin and crystalline silicotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-022, Hanford Tank Waste Supernatant Cesium Removal Test Plan.

  20. Transition of cesium in food chains [after Chernobyl catastrophe

    International Nuclear Information System (INIS)

    An investigation of 25,000 samples of foodstuffs and feedstuffs in Czechoslovakia, contaminated by fall-out cesium after the accident in the Chernobyl nuclear power plant, performed from May 5, 1986 to March 31, 1988, revealed that both the values of cesium transfer-factors in food--animal tissues--milk transitions and the values of biological half-life of cesium are functions of internal and external conditions of contamination. Organism individuality as the main internal condition causes the variance of about +/- 50% of the mean value of the respective transfer-factor. Through the external conditions, mainly the environmental contamination level, type of ingested food and time of ingestion, the mean values of transfer-factors are influenced up to 500%, e.g. to the value of 0.5. But this value converges with growing up contamination of food and environment to the limit of 0.3. The first two to three biological half-lives after the last ingestion of contaminated food are up to ten-times shorter than those at stabilized state

  1. Cesium transfer to agricultural crops for three years after Chernobyl

    International Nuclear Information System (INIS)

    In 1986 about 50 farms in the fallout region were selected for sampling at fixed sites of the soil surface layer and of the grassland and grain crops to come. The aim was to cover the different soil types and the farming practices of the region during studies on the transfer levels and on the change with time in transfer of cesium to the crops. It was found that the transfer level, as expected, was much higher for the grassland than for the grain crops. However, within both groups of considerable variation in the transfer level for the same year as measured by the transfer factors has occurred. For the former crops it can be concluded that the transfer factor during year 1 depends on the interception capacity of the plant cover and on the dilution by growth i.e on soil fertility and on fertilization level. In the following years the cesium TF-value for the grass cover was reduced by a factor from 2 to about 10. The reduction rate differed above all between the organic soils and the mineral soils and should largely depend on the type of the grass cover, on the different cesium fixing capacities of the two soil groups and on the potassium fertilization level. On ploughed land the transfer by root uptake to grain crops was about one magnitude lower than the transfer to the hey crops. (orig.)

  2. Solidification of cesium and strontium with zeolites

    International Nuclear Information System (INIS)

    The thermal change of zeolites and the elution property of nuclides from calcined matters were experimentally studied in order to produce the solid of low leaching property. The method includes the ion exchange of nuclides in radioactive waste solution and the calcination at a high temperature. Differential thermal analysis, thermal gravity analysis and X-ray diffraction method were employed to see the occurrence of recrystallization of Na type, Cs type, Sr type of the zeolites at a high temperature. Samples were synthetic zeolites including A type, X type, Y type and mordenite (zolen, hereafter referred to as S.M.), and natural mordenite. The ion exchanging capacity for Cs and Sr was measured, using the above zeolites. The adsorption was measured by the column method, using Cs-135 and Sr-85 as tracers. The leaching test of the zeolites calcined at 8000C, 9000C, 1,0000C and 1,1000C for 3 hours was performed by the atomic light absorption method. The daily change of the leaching ratio was observed according to the method of IAEA. The experiment revealed that CsA and CsX recrystallized at 1,0000C or above, whereas mordenite did not recrystallize even at the calcining temperature of 1,1000C, and it was leachable. The calcined CsY showed much lower leaching value than the other methods such as cement solidification and glass solidification. The leaching into sea water was five times as much as that into distilled water. (Iwakiri, K.)

  3. Cesium transport in Four Mile Creek of the Savannah River Plant

    International Nuclear Information System (INIS)

    The behavior of a large radioactive cesium release to a Savannah River Plant (SRP) stream was examined using a stable cesium release to Four Mile Creek. Measurements following the release show that most of the cesium released was transported downstream; however, sorption and desorption decreased the maximum concentration and increased the travel time and duration, relative to a dye tracer, at sampling stations downstream. The study was made possible by the development of an analytical technique using ammonium molybdophosphate and neutron activation that permitted the measurement of stable cesium concentrations as low as 0.2 μg/L

  4. Radioactive cesium dynamics derived from hydrographic observations in the Abukuma River Estuary, Japan.

    Science.gov (United States)

    Kakehi, Shigeho; Kaeriyama, Hideki; Ambe, Daisuke; Ono, Tsuneo; Ito, Shin-Ichi; Shimizu, Yugo; Watanabe, Tomowo

    2016-03-01

    Large quantities of radioactive materials were released into the air and the ocean as a result of the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, caused by the 2011 Tohoku earthquake and the subsequent major tsunami off the Pacific coast. There is much concern about radioactive contamination in both the watershed of the Abukuma River, which flows through Fukushima Prefecture, and its estuary, where it discharges into the sea in Miyagi Prefecture. We investigated radioactive cesium dynamics using mixing diagrams obtained from hydrographic observations of the Abukuma River Estuary. Particulate radioactive cesium dominates the cesium load in the river, whereas the dissolved form dominates in the sea. As the salinity increased from <0.1 to 0.1-2.3, the mixing diagram showed that dissolved radioactive cesium concentrations increased, because of desorption. Desorption from suspended particles explained 36% of dissolved radioactive cesium in estuarine water. However, the dissolved and particulate radioactive cesium concentrations in the sea decreased sharply because of dilution. It is thought that more than 80% of the discharged particulate radioactive cesium was deposited off the river mouth, where the radioactive cesium concentrations in sediment were relatively high (217-2440 Bq kg(-1)). Radioactive cesium that was discharged to the sea was transported southward by currents driven by the density distribution. PMID:26698826

  5. Structure of cesium loaded iron phosphate glasses: An infrared and Raman spectroscopy study

    International Nuclear Information System (INIS)

    The structure of cesium loaded iron phosphate glasses (IPG) was investigated using infrared and Raman spectroscopy. The spectra of the cesium doped samples revealed a structural modification of the parent glass owing to the incorporation of cesium. The structural changes could be correlated with the variation observed in the glass transition temperature of these glasses. Increased Cs-mediated cationic cross linking appears to be the reason for the initial rise in glass transition temperature up to 21 mol% Cs2O in IPG; while, breakdown of the phosphate network with increasing cesium content, brings down the glass transition temperature.

  6. Radioactive cesium content in selected food products. Pt. 1. Radioactive cesium content in dried milk (1987-1988)

    International Nuclear Information System (INIS)

    The content of radioactive cesium in dried and dried skimmed milk from selected dairies was double determined. The highest content was found in samples from milk from OSM Siedlce (98 Bq/kg) and skimmed milk from Radzyn Podlaski and Ostroleka, (the former 90, the latter 62 Bq/kg). The lowest level of radioactive cesium was observed in samples from dried milk from Sieradz, Slups, Wrzesnia, Olecko and Elblag (about or below 10 Bq/kg). Although those levels of contamination with radiocesium did not exceed values recommended by FAO they were determined as high for year 1987/88 as compared milk dates from previous 1985 year. (author). 13 refs, 4 tabs

  7. Radioactive cesium. Dynamics and transport in forestal food-webs; Radioaktivt cesium. Dynamik och transport i skogliga naeringsvaevar

    Energy Technology Data Exchange (ETDEWEB)

    Palo, T.; Nelin, P. [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Animal Ecology; Bergman, R.; Nylen, T. [FOA NBC Defence, Umeaa (Sweden)

    1995-12-01

    This report summarises results from a radioecological study during 1994-1995 concerning turnover, redistribution and loss of radioactive Cesium (134 and 137) in boreal forest ecosystems, as well as uptake and transfer in important food-chains over moose, vole and vegetation. The basis for this report are 9 publications published 1994-95. These reports are presented in summary form. 9 refs, 17 figs.

  8. Compliance with the Nevada Test Site's waste acceptance criteria for vitrified cesium-loaded crystalline silicotitanate (CST)

    International Nuclear Information System (INIS)

    Oak Ridge National Laboratory (ORNL) and Savannah River Technology Center (SRTC) are involved in a joint project for immobilization of radionuclides from the Melton Valley Storage Tanks (MVST) at Oak Ridge (OR). The supernate from Tank W-29 of the MVST will be treated by passage through a crystalline silicotitanate (CST) ion exchange medium. The CST was designed to sorb cesium, the primary radio nuclide (Cs-137) in the supernate of MVST's. A smaller amount of strontium (Sr-90) will also be sorbed. This demonstration will be performed by ORNL. One column volume of cesium-loaded CST (∼10 gallons or 38 liters) will then be shipped to SRTC where it will be mixed with glass formers and fed as an aqueous slurry to a joule-heated melter within the SRTC Shielded Cells. A borosilicate glass formulation which will incorporate the CST has been developed as part oft SRTC's role in this project. The molten glass (∼1150 degrees C) will be poured into 500 ml stainless steel beakers which in turn will be placed in 30 gallon drums for disposal. An import ampersand f part of this project is to demonstrate that the glass waste form produced will meet the Waste Acceptance Criteria (WAC) for disposal at the Nevada Test Site (NTS). If vitrification of the cesium-loaded CST is implemented as the immobilization method for all of the MVST supernate, then it is essential to demonstrate that the waste can be disposed of at an acceptable disposal facility. NTS accepts low-level radioactive waste as long as it is not TRU and not hazardous. This paper documents the efforts in the development stage of this work to integrate the requirements of NTS into the formulation and processing efforts. This work is funded by the Tank Focus Area with additional funding for ORNL provided by EM-30 at OR

  9. Elastic and inelastic scattering of cesium, cesium iodide, and cesium chloride by argon and xenon in the crossed atomic and molecular beams

    International Nuclear Information System (INIS)

    Velocity and angular distributions of cesium atoms and two cesium halide molecules scattered by rare gas atoms have been measured for the following systems at the indicated initial relative collision energies, anti E: Cs + Ar, anti E = 0.94, 1.29, and 1.85 kcal/mole; Cs + Xe, E = 1.15, 1.91, and 3.10 kcal/mole; Csl + Ar, anti E = 1.06, 1.46, and 2.08 kcal/mole; CsI + Ar, anti E = 1.36, 1.63, and 1.94 kcal/mole; CsI + Xe, anti E = 1.52, 2.52, and 4.09 kcal/mole. At the collision energies indicated the atom-atom scattering can only be elastic. Thus the experiments with those systems can be used for apparatus calibration and a standard of comparison for the diatom-atom experiments. The velocity distributions in the diatom-atom systems are analyzed for the relative contributions of elastic and inelastic scattering

  10. Simultaneous solid phase extraction of cobalt, strontium and cesium from liquid radioactive waste using microcrystalline naphthalene

    International Nuclear Information System (INIS)

    Most of the procedures developed for the extraction of cobalt, strontium and cesium by solid phase extraction do not employ simultaneous extraction of them. In this study, rapid simultaneous removal of Co2+, Sr2+ and Cs+ on microcrystalline naphthalene as solid-phase extractant was investigated. These ions were allowed to form chelates with oxine and then adsorbed on freshly microcrystalline naphthalene from aqueous solutions. The solid phase extraction procedure (SPE) was optimized by using model solution containing Co2+, Sr2+ and Cs+ in batch system. The effects of different parameters such as variation in pH, reagent concentration, standing time, naphthalene solution concentration and contact time on the simultaneous removal of these ions was studied. The obtained results indicated that, sorption was found to be rapid, and the percentage removal of Co2+, Sr2+ and Cs+ was found to be 98, 79 and 68% within 10 min, respectively. The kinetics of the sorption process was investigated to understand the kinetic characteristics of sorption of metal chelates onto microcrystalline naphthalene. The developed procedure has been successfully applied to the removal and recovery of 60Co and 134Cs from liquid radioactive waste. The parameters can be used for designing a plant for treatment of wastewater economically.

  11. Current densities and closure rates in diodes containing laser-driven, cesium-coated thermionic cathodes

    Science.gov (United States)

    Lee, C.; Oettinger, P. E.

    1985-09-01

    Cathodes emitting electron current pulses of 100-1,000 A/sq cm for durations of longer than 1 microsecond, with very low emittance, are desirable for free electron laser and high-power microwave tube applications. Not all of these criteria can be satisfied by either dispenser thermionic cathodes or plasma forming field emitters. However, pulse-laser heated smooth cesiated refractory metal surfaces have the potential to achieve these conditions. In this paper, test results from low-voltage (2-20 kV) diodes containing cesiated tungsten cathodes are discussed. Space-charge-limited current densities of up to 30 A/sq cm were obtained in fields with maximum strengths of 40 kV/cm. Plasma closure rates at these currents were measured to be 0.17-0.4 cm/microsecond. Such slow velocity fronts are postulated to be due to the domination of the plasma by massive cesium ions generated from species desorbed from the cathode, rather than to light hydrogen ions (as in the case of field-emission-type cathodes).

  12. Current densities and closure rates in diodes containing laser-driven, cesium-coated thermionic cathodes

    International Nuclear Information System (INIS)

    Cathodes emitting electron current pulses of 102--103 A/cm2 for durations of longer than 1 μs, with very low emittance, are desirable for free electron laser and high-power microwave tube applications. Not all of these criteria can be satisfied by either dispenser thermionic cathodes or plasma forming field emitters. However, pulse-laser heated smooth cesiated refractory metal surfaces have the potential to achieve these conditions. In this paper, test results from low-voltage (2--20 kV) diodes containing cesiated tungsten cathodes are discussed. Space-charge-limited current densities of up to 30 A/cm2 were obtained in fields with maximum strengths of 40 kV/cm. Plasma closure rates at these currents were measured to be 0.17--0.4 cm/μs. Such slow velocity fronts are postualted to be due to the domination of the plasma by massive cesium ions generated from species desorbed from the cathode, rather than to light hydrogen ions (as in the case of field-emission-type cathodes)

  13. Negative ion source development for fusion application (invited).

    Science.gov (United States)

    Takeiri, Yasuhiko

    2010-02-01

    Giant negative ion sources, producing high-current of several tens amps with high energy of several hundreds keV to 1 MeV, are required for a neutral beam injector (NBI) in a fusion device. The giant negative ion sources are cesium-seeded plasma sources, in which the negative ions are produced on the cesium-covered surface. Their characteristic features are discussed with the views of large-volume plasma production, large-area beam acceleration, and high-voltage dc holding. The international thermonuclear experimental reactor NBI employs a 1 MeV-40 A of deuterium negative ion source, and intensive development programs for the rf-driven source plasma production and the multistage electrostatic acceleration are in progress, including the long pulse operation for 3600 s. Present status of the development, as well as the achievements of the giant negative ion sources in the working injectors, is also summarized. PMID:20192420

  14. Negative ion source development for fusion application (invited)

    International Nuclear Information System (INIS)

    Giant negative ion sources, producing high-current of several tens amps with high energy of several hundreds keV to 1 MeV, are required for a neutral beam injector (NBI) in a fusion device. The giant negative ion sources are cesium-seeded plasma sources, in which the negative ions are produced on the cesium-covered surface. Their characteristic features are discussed with the views of large-volume plasma production, large-area beam acceleration, and high-voltage dc holding. The international thermonuclear experimental reactor NBI employs a 1 MeV-40 A of deuterium negative ion source, and intensive development programs for the rf-driven source plasma production and the multistage electrostatic acceleration are in progress, including the long pulse operation for 3600 s. Present status of the development, as well as the achievements of the giant negative ion sources in the working injectors, is also summarized.

  15. High-capacity, selective solid sequestrants for innovative chemical separation: Inorganic ion exchange approach

    International Nuclear Information System (INIS)

    The approach of this task is to develop high-capacity, selective solid inorganic ion exchangers for the recovery of cesium and strontium from nuclear alkaline and acid wastes. To achieve this goal, Pacific Northwest Laboratories (PNL) is collaborating with industry and university participants to develop high capacity, selective, solid ion exchangers for the removal of specific contaminants from nuclear waste streams

  16. Modeling of Crystalline Silicotitanate Ion Exchange Columns Using Experimental Data from SRS Simulated Waste

    International Nuclear Information System (INIS)

    Non-elutable ion exchange using crystalline silicotitanate is being considered for removing cesium from Savannah River Site radioactive waste. The construction cost of this process depends strongly on the size of the ion exchange column required to meet product specifications

  17. Selective separation of cesium from simulated high level liquid waste solution using 1,3-dioctyloxy calix[4]arene-benzo-crown-6

    International Nuclear Information System (INIS)

    The 25,27-di(octyloxy)calix[4]arenebenzocrown-6 (CBC) in 1,3-alternate conformation was synthesized indigenously starting from its intermediates in good yield and purity. The extraction studies of CBC were carried out by using two different phase modifiers namely isodecyl alcohol and ortho-nitrophenyl hexyl ether. Detailed investigations on the effect of various parameters like, concentration of phase modifiers, aqueous phase acidity, ligand concentration, nitrate ion concentration and effect of temperature on extraction of cesium have been carried out. The concentration of phase modifiers was optimized to be 30 % in n-dodecane to ensure optimum extraction of cesium. Stoichiometry of the extracted complex determined by slope analysis method reveals 1:1:1 molar ratio for CsNO3:CBC:HNO3. The extraction process was found to be exothermic as determined from the plot of log Kex versus 1/T. The solvent system with a composition 0.01 M CBC/30 % phase modifier/n-dodecane was found to be effective for selective separation of cesium from simulated high level liquid waste solution. (author)

  18. Streaming potentials in gramicidin channels measured with ion-selective microelectrodes.

    OpenAIRE

    Tripathi, S; Hladky, S B

    1998-01-01

    Streaming potentials have been measured for gramicidin channels with a new method employing ion-selective microelectrodes. It is shown that ideally ion-selective electrodes placed at the membrane surface record the true streaming potential. Using this method for ion concentrations below 100 mM, approximately seven water molecules are transported whenever a sodium, potassium, or cesium ion, passes through the channel. This new method confirms earlier measurements (Rosenberg, P.A., and A. Finke...

  19. Cesium-137 inventories in undisturbed areas in different regions of Brazil

    International Nuclear Information System (INIS)

    Cesium-137 is an anthropogenic radionuclide introduced in the environment in the early of 1960s to the end of 1970s. The Cesium-137 has very used to assess soil redistribution in the landscape because this is very tight in the fine soil particles and its movement in the landscape is due to soil redistribution. To use Cesium-137 to assess soil redistribution is need to known the Cesium-137 inventory in an area that not has experimented soil erosion neither soil deposition. So, this work present Cesium-137 inventories in undisturbed areas in different regions of Brazil, from South to Northeast of Brazil. The inventories in these areas represent the variational deposition of Cesium-137 in the whole national territory of Brazil. The inventories of Cesium-137 varied from 200 ± 15 Bq.m-2 for South region to 15 ± 2 Bq.m-2 for Northeast region. Moreover, was verified that the Cesium- 137 inventories depend on latitude and altitude of the area. (author)

  20. Vacuum squeezed light for atomic memories at the D2 cesium line

    CERN Document Server

    Burks, Sidney; Giacobino, Elisabeth; Laurat, Julien; Ortalo, Jérémie; Jia, Xiaojun; Villa, Fabrizio; Chuimmo, Antonino

    2008-01-01

    We report the experimental generation of squeezed light at 852 nm, locked on the Cesium D2 line. 50% of noise reduction down to 50 kHz has been obtained with a doubly resonant optical parametric oscillator operating below threshold, using a periodically-polled KTP crystal. This light is directly utilizable with Cesium atomic ensembles for quantum networking applications

  1. Peculiarities of presence of cesium-137 in soil at Azgir test site grounds

    International Nuclear Information System (INIS)

    The granulometric composition of soil and the distribution of cesium-137 by soil fractions at the Azgir test site was determined. The characterization of cesium-137 presence in the layer of the thickness of 1 cm of the surface soil was gave. (author)

  2. Velocity Distribution of Effective Atoms in a Small Optically Pumped Cesium Beam Frequency Standard

    Institute of Scientific and Technical Information of China (English)

    CHEN Jingbiao; WANG Fengzhi; YANG Donghai; WANG YiQiu

    2001-01-01

    In this paper, the velocity distribution of effective atoms in a small optically pumped cesium beam frequency standard has been achieved from the Fourier transforms of the experimentally recorded Ramsey patterns. The result fits well with the theoretical calculation. The second order Doppler shift correction of the small cesium atomic clock is obtained from the velocity distribution of effective atoms.

  3. Cesium-134 and cesium-137 in honey bees and cheese samples collected in the U.S. after the Chernobyl accident

    International Nuclear Information System (INIS)

    As a result of the Chernobyl accident on April 25, 1986, possible radioactive contamination of honey bees and cheese sampled in several areas of the United States were measured. Of bees collected in May and June of 1986 in both Oregon and New York, only those from Oregon showed detectable levels of cesium-134 (T1/2 = 2.05 years), a radionuclide which would have originated from the Chernobyl incident. Cheese produced in Oregon and New York before the accident showed only cesium-137 (T1/2 = 30.23 years) but cheese produced afterwards (May and September, 1986) in Oregon contained cesium-134. Cheese produced in Ohio and California at the time of the accident and thereafter contained only cesium-137. In general, the levels of radioactivity were higher in the West coast samples as compared to those taken in the East. The levels of radioactivity detected were considered to be toxicologically of no consequence. (author)

  4. Sorption of iodine, chlorine, technetium and cesium in soil

    International Nuclear Information System (INIS)

    The safety assessment of final disposal of spent nuclear fuel will include an estimate for the behavior of waste nuclides in the biosphere. As a part of this estimate also the sorption of radioactive iodine, chlorine, technetium and cesium in soil is to be considered. The chemistry and the sorption of these radionuclides in soils are described in this literature survey. Behavior of I-129, Cl-36 and Tc-99 in the environment is of great interest because of their long half-lives and relatively high mobilities. The importance of Cs-135 arises from its high content in spent nuclear fuel and long physical half-life, even though it is considered relatively immobile in soil. Factors affecting the migration and sorption of radionuclides in soils can be divided into elemental and soil specific parameters. The most important elemental factor is the speciation of the element, which is influenced by the soil redox potential, pH and complex forming ligands. Soil micro-organisms can either serve as sorbents for radionuclides or affect their speciation by altering the prevailing soil redox conditions. Soil organic matter content and mineral properties have a marked influence on the retention of radionuclides. The sorption of anionic radionuclides such as I-, Cl- and TcO4 - is pronounced in the presence of organic matter. Clay minerals are known to bound cesium effectively. The effect of speciation of radioactive iodine, chlorine, technetium and cesium in soil is considered in this study, as well as the effect of soil micro-organisms, organic matter and mineral properties. (orig.)

  5. Cesium-137 inventory of the undisturbed soil areas in the Londrina Region, Parana, Brazil

    International Nuclear Information System (INIS)

    Cesium-137 is an artificial radionuclide introduced in the environment through the radioactive fallout of the superficial tests of nuclear weapons. The cesium-137 deposition occurred to middles of the 1980-decade and, due to the Chernobyl accident, great part of Europe had a additional fallout of cesium-137. The contaminations of this accident do not have reached Southern Hemisphere. Cesium-137 is an alkaline metal, high electropositive, that in contact with the soil is strongly adsorbed to the clay in the FES (Frayed Edge Sites) and RES (Regular Edge Sites) positions, and it movement by chemical processes in the soil is insignificant. Because of this, cesium-137 became a good soil marker, and its movement is related to the soil movement particles, so that the cesium-137 have been used in the study of the soil redistribution processes, as a tool of quantifying the rates of soil losses and gain. To use this methodology, it is necessary the knowledge of the reference inventory of cesium-137, that is given as function of the total concentration of cesium-137 deposited in an area by the radioactive fallout. If a sampling point presents less cesium-137 than the reference inventory, this point is considered a point with soil loss; otherwise, the point is considered a point with soil deposition. To evaluate the cesium-137 inventory in the Londrina region, four areas of the undisturbed soil were sampling in grid of 3x3, with a distance of 9 meters among the points. Of these four sampling areas, three areas were of native forest (labeled Mata1, Mata2 and Mata UEL), and one was a pasture area. Cesium-137 inventory was 223 ± 41 Bq m-2, 240 ± 65 Bq m-2 and 305 ± 36 Bq m-2 for Mata UEL, Mata1 and Mata2, respectively, and of 211 ± 28 Bq m-2 for the native pasture. Considering the deviation in each value, it is not possible to conclude that there are differences among the values of cesium-137 inventory, so that the average reference inventory of cesium-137 for the Londrina

  6. Characterizing optical dipole trap via fluorescence of trapped cesium atoms

    Institute of Scientific and Technical Information of China (English)

    LIU; Tao; GENG; Tao; YAN; Shubin; LI; Gang; ZHANG; Jing; WANG; Junmin; PENG; Kunchi; ZHANG; Tiancai

    2006-01-01

    Optical dipole trap (ODT) is becoming an important tool of manipulating neutral atoms. In this paper ODT is realized with a far-off resonant laser beam strongly focused in the magneto-optical trap (MOT) of cesium atoms. The light shift is measured by simply monitoring the fluorescence of the atoms in the magneto-optical trap and the optical dipole trap simultaneously. The advantages of our experimental scheme are discussed, and the effect of the beam waist and power on the potential of dipole trap as well as heating rate is analyzed.

  7. Cesium fallout in Norway after the Chernobyl accident

    International Nuclear Information System (INIS)

    Results of country-wide measurements of 137Cs and 134 Cs in soil samples in Norway after the Chernobyl accident are reported. The results clearly demonstrates that municipalities in the central part of southern Norway, Troendelag and the southern part of Nordland, have been rather heavily contaminated. The total fallout of 137Cs and 134Cs from the Chernobyl accident in Norway is estimated to 2300 TBq and 1200 TBq, respectively. This is approximately 6% of the cesium activity released from the reactor

  8. Sensitive Detection of Cold Cesium Molecules by Radiative Feshbach Spectroscopy

    OpenAIRE

    Chin, Cheng; Kerman, Andrew J.; Vuletić, Vladan; Chu, Steven

    2002-01-01

    We observe the dynamic formation of $Cs_2$ molecules near Feshbach resonances in a cold sample of atomic cesium using an external probe beam. This method is 300 times more sensitive than previous atomic collision rate methods, and allows us to detect more than 20 weakly-coupled molecular states, with collisional formation cross sections as small as $\\sigma =3\\times 10^{-16}$cm$^2$. We propose a model to describe the atom-molecule coupling, and estimate that more than $2 \\times 10^5$ $Cs_2$ mo...

  9. Specific heat and thermodynamic properties of the cesium perchlorate

    International Nuclear Information System (INIS)

    The cesium perchlorate specific heat has been measured in a vacuum adiabatic microcalorimeter in the 10-365 K range. On the basis of the data obtained the thermodynamic functions are calculated. Csub(p)sup(0) (298.15 K) = 110.4+-0.2 J/Kxmol; S0 (298.15 K)=175.9+-0.5 J/Kxmol; H0 (298.15 K) - H0(0)=22280+-50 J/mol; - [G0 (289.15 K) - H0(0)]/T = 101.2+-0.2 J/Kxmol

  10. Investigation of the behavior during incineration of cesium adsorbed in vegetation waste

    International Nuclear Information System (INIS)

    The decontamination of wood and grass contaminated by radioactive cesium released after a nuclear power plant accident is a significant problem. During this research, the behavior of radioactive cesium during incineration was investigated experimentally. Non-radioactive cesium chloride was adsorbed into sunflower and wood pellet samples, and was burned in a lab-scale fluidized bed combustor. Up to 70% of the cesium was transferred to fly ash, which is captured in the quartz filter of the exhaust line. The concentration of cesium in the fly ash is 10 times greater than in the bottom ash, as the amount of fly ash makes up approximately 20% of the entire ash content. Careful management is vital when handling and disposing of fly ash generated from the incineration of vegetation waste. (author)

  11. The University of Washington polarized ion source

    International Nuclear Information System (INIS)

    A colliding-beams polarized ion source has been in operation for nuclear physics experiments at the University of Washington tandem-linac facility since late 1987. Thermal beams of polarized atomic hydrogen or deuterium are ionized by charge exchange in collisions with a collinear, fast, neutral cesium beam. Negative ions are extracted and the polarization symmetry axis is precessed to any desired direction in a crossed-field spin precessor. The design of the cesium beam system differs from previous sources in that magnetic deflection and focusing are used and beams of several milliamperes at energies of 40 keV are produced. The source is controlled by a microprocessor based system which is connected via fiber optic links to the main linac control and data acquisition computers. To date, currents of 1μA and polarizations in excess of 90% have been produced. 3 refs., 2 figs

  12. Diffusion of radiocesium in natural and synthetic ion exchangers

    International Nuclear Information System (INIS)

    Sorption of radiocesium on natural zeolites from Zaloshka gorica has been studied at different conditions and compared with that on Dowex 50 strongly acidic ion exchanger. The diffusion coefficients of cesium in the system Dowex-solution and zeolite-water were determined. The energy of activation for the diffusion found is 5.5 in first case and 13.6 kcal/mole in the second. The concentration profiles for the diffusion of cesium from a layer at different times are given. (author)

  13. Polarized H- ion source development for the AGS

    International Nuclear Information System (INIS)

    The polarized H- ion source that Argonne National Laboratory and Yale University are building for the AGS polarized beam facility is based on the crossed-beam concept in which a polarized atomic-hydrogen beam, H0, is ionized to H- by a fast neutral cesium beam, Cs0. We describe our studies which will aid in achieving a high intensity polarized H- beam. In particular, we describe time-of-flight studies on the atomic beam and the effect of dissociation nozzle cooling on the velocity distribution. The cesium gun design is described, and a brief discussion of the H0-Cs0 interaction region is given

  14. Humic complexes and sorption of cesium, strontium, europium and plutonium. Author-review of dissertation submitted for fulfillment of the scientific degree 'Philosophiae doctor' (Ph.D.)

    International Nuclear Information System (INIS)

    Humic acid (HA) solutions of radionuclides (cesium, strontium, europium, plutonium) and their sorption on various natural and synthetic sorbents were investigated from the point of view of radionuclide mobility in environment. The solubility of HA depends on pH, ionic strengths and the concentration of HA. The HA sorption data were treated and fitted by means of various models of sorption isotherm. The three-parameter Sips isotherm of HA sorption data appeared to be the best fit for most systems. Radiocesium sorption decreases in the order zeolite > nickel cyano-ferrate-silica gel > montmorillonite > aerogel > silica gel > and HA suppresses the sorption. The effect of HA addition on the capacity of montmorillonite to sorb radioactive cesium and strontium was modeled by two-parameters of Sips isotherm for HA sorption and by a two-site distribution of radionuclide ions. The difference between distribution ratios of the cesium and strontium on a free and coated ('blocked') by HA montmorillonite surface was found, but no substantial complexation of the ions was observed. It was confirmed that the 'specific radiocesium interception potential' (SRIP) is influenced by the sorption of HAs and also by a cesium carrier in the concentration region, which may occur in natural materials and potassium salts. A comparative study of cesium and strontium with polyvalent cations europium(III) and plutonium(IV) on well-defined montmorillonite in the presence of HA verified the '2-sites-2-species' model of radionuclide sorption. Consistent interaction constants of polyvalent elements with humic ligands in solution and on the montmorillonite surface were obtained. Special attention deserves to be given to a more peculiar complexation and distribution of plutonium(IV), where sorption of plutonium HAs may take place. The high-performance size-exclusion chromatographic behavior of HA and its complexes are strongly influenced by the pH as well as by the ionic strength of the eluent and the

  15. Inductively driven surface-plasma negative ion source for N-NBI use (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Belchenko, Yu., E-mail: belchenko@inp.nsk.su; Abdrashitov, G.; Deichuli, P.; Ivanov, A.; Gorbovsky, A.; Kondakov, A.; Sanin, A.; Sotnikov, O.; Shikhovtsev, I. [Budker Institute of Nuclear Physics, Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2016-02-15

    The long-pulse surface-plasma source prototype is developed at Budker Institute of Nuclear Physics for negative-ion based neutral beam injector use. The essential source features are (1) an active temperature control of the ion-optical system electrodes by circulation of hot thermal fluid through the channels, drilled in the electrode bodies, (2) the concaved transverse magnetic field in the extraction and acceleration gaps, preventing the electrons trapping and avalanching, and (3) the directed cesium deposition via distribution tubes adjacent to the plasma grid periphery. The long term effect of cesium was obtained just with the single cesium deposition. The high voltage strength of ion-optical system electrodes was improved with actively heated electrodes. A stable H{sup −} beam with a current ∼1 A and energy 90 keV was routinely extracted and accelerated.

  16. Inductively driven surface-plasma negative ion source for N-NBI use (invited)

    Science.gov (United States)

    Belchenko, Yu.; Abdrashitov, G.; Deichuli, P.; Ivanov, A.; Gorbovsky, A.; Kondakov, A.; Sanin, A.; Sotnikov, O.; Shikhovtsev, I.

    2016-02-01

    The long-pulse surface-plasma source prototype is developed at Budker Institute of Nuclear Physics for negative-ion based neutral beam injector use. The essential source features are (1) an active temperature control of the ion-optical system electrodes by circulation of hot thermal fluid through the channels, drilled in the electrode bodies, (2) the concaved transverse magnetic field in the extraction and acceleration gaps, preventing the electrons trapping and avalanching, and (3) the directed cesium deposition via distribution tubes adjacent to the plasma grid periphery. The long term effect of cesium was obtained just with the single cesium deposition. The high voltage strength of ion-optical system electrodes was improved with actively heated electrodes. A stable H- beam with a current ˜1 A and energy 90 keV was routinely extracted and accelerated.

  17. Inductively driven surface-plasma negative ion source for N-NBI use (invited)

    International Nuclear Information System (INIS)

    The long-pulse surface-plasma source prototype is developed at Budker Institute of Nuclear Physics for negative-ion based neutral beam injector use. The essential source features are (1) an active temperature control of the ion-optical system electrodes by circulation of hot thermal fluid through the channels, drilled in the electrode bodies, (2) the concaved transverse magnetic field in the extraction and acceleration gaps, preventing the electrons trapping and avalanching, and (3) the directed cesium deposition via distribution tubes adjacent to the plasma grid periphery. The long term effect of cesium was obtained just with the single cesium deposition. The high voltage strength of ion-optical system electrodes was improved with actively heated electrodes. A stable H− beam with a current ∼1 A and energy 90 keV was routinely extracted and accelerated

  18. Electrochemical assessment of water|ionic liquid biphasic systems towards cesium extraction from nuclear waste.

    Science.gov (United States)

    Stockmann, T Jane; Zhang, Jing; Montgomery, Anne-Marie; Ding, Zhifeng

    2014-04-22

    A room temperature ionic liquid (IL) composed of a quaternary alkylphosphonium (trihexyltetradecylphosphonium, P66614(+)) and tetrakis(pentafluorophenyl)borate anion (TB(-)) was employed within a water|P66614TB (w|P66614TB or w|IL) biphasic system to evaluate cesium ion extraction in comparison to that with a traditional water|organic solvent (w|o) combination. (137)Cs is a major contributor to the radioactivity of spent nuclear fuel as it leaves the reactor, and its extraction efficiency is therefore of considerable importance. The extraction was facilitated by the ligand octyl(phenyl)-N,N'-diisobutylcarbamoylphosphine oxide (CMPO) used in TRans-Uranium EXtraction processes and investigated through well established liquid|liquid electrochemistry. This study gave access to the metal ion to ligand (1:n) stoichiometry and overall complexation constant, β, of the interfacial complexation reaction which were determined to be 1:3 and 1.6×10(11) at the w|P66614TB interface while the study at w|o elicited an n equal to 1 with β equal to 86.5. Through a straightforward relationship, these complexation constant values were converted to distribution coefficients, δ(α), with the ligand concentrations studied for comparison to other studies present in the literature; the w|o and w|IL systems gave δ(α) of 2 and 8.2×10(7), respectively, indicating a higher overall extraction efficiency for the latter. For the w|o system, the metal ion-ligand stoichiometries were confirmed through isotopic distribution analysis of mass spectra obtained by the direct injection of an emulsified water-organic solvent mixture into an electron spray ionization mass spectrometer. PMID:24703212

  19. Molecular and negative ion production by a standard electron cyclotron resonance ion source.

    Science.gov (United States)

    Rácz, R; Biri, S; Juhász, Z; Sulik, B; Pálinkás, J

    2012-02-01

    Molecular and negative ion beams, usually produced in special ion sources, play an increasingly important role in fundamental and applied atomic physics. The ATOMKI-ECRIS is a standard ECR ion source, designed to provide highly charged ion (HCI) plasmas and beams. In the present work, H(-), O(-), OH(-), O(2)(-), C(-), C(60)(-) negative ions and H(2)(+), H(3)(+), OH(+), H(2)O(+), H(3)O(+), O(2)(+) positive molecular ions were generated in this HCI-ECRIS. Without any major modification in the source and without any commonly applied tricks (such as usage of cesium or magnetic filter), negative ion beams of several μA and positive molecular ion beams in the mA range were successfully obtained. PMID:22380160

  20. Photo-association of cold cesium atoms. Formation and characterisation of a cold cloud of diatomic cesium molecules

    International Nuclear Information System (INIS)

    In a photo-association process, two colliding cold cesium atoms absorb one photon to form an ultracold molecule, electronically excited in a well defined ro-vibration level. Because of the small initial kinetic energy of the free atoms, the photo-association is resonant and permits high resolution spectroscopy of long-range states. We report spectra for states correlated to the excited limit 6S+6P. The 1u (6S+6P3/2) state is a pure long-range molecules. It hardly consists in a molecule, but rather in a pair of two atoms linked at 1, 5 nm by the multipolar electrostatic interaction. The intensity modulation of spectral lines for a given vibrational progression reflects the nodal structure of the radial s-wave function of two ground state atoms. The photo-association of the state 0g-(6S +6P3/2) of polarized atoms permits determining the scattering length of the triplet state of cesium (aT = -530 a0) and the Van der Waals parameter of the molecular ground state (C6 = 6510 u.a.). Photo-association of cold cesium atoms also leads to the formation of translationally cold molecules in singlet and triplet fundamental states after spontaneous emission of the excited molecules. Various schemes are characterized. The particular double-well shape of 0g-(6S+6P3/2) and 1u(6S+6P3/2) states creates a Condon point at intermediate distance. These states constitute ideal cases for very efficient formation of cold molecules. The cold molecular cloud is analyzed: temperatures as low as 20 micro-Kelvin are measured and the distribution of the ro-vibrational levels is studied. The efficiencies of the photo-association process and of the formation of cold molecules are measured, and compared with theoretical calculations. (author)

  1. Fabrication, characterization and radiation damage stability of hollandite based ceramics devoted to radioactive immobilisation; Synthese, caracterisation et etude du comportement sous irradiation electronique de matrices de type hollandite destinees au confinement du cesium radioactif

    Energy Technology Data Exchange (ETDEWEB)

    Aubin-Chevaldonnet, V. [CEA Valrho, Dir. de l' Energie Nucleaire (DEN/DETCD/SCDV), Dept. d' Etudes du Traitement et du Conditionnement des Dechets, Service de Conditionnement des Dechets et Vitrification, 30 - Marcoule (France)

    2004-11-01

    Research on treating specifically the long-lived and high level nuclear wastes, notably cesium, is currently carried out in France. Cesium immobilization in host matrices of high chemical durability constitutes the favoured option. Hollandite matrix is a good candidate because of its high cesium incorporation ability and its excellent chemical stability. During this study, different compositions of hollandite ceramics Ba{sub x}Cs{sub y}C{sub z}Ti{sub 8-z}O{sub 16} (C = Al{sup 3+}, Cr{sup 3+}, Ga{sup 3+}, Fe{sup 3+}, Mg{sup 2+}, Sc{sup 3+}), synthesized by oxide route, were characterized in terms of structure, microstructure and physical and chemical properties. Iron ions seems to be the most suitable of the studied C cations to get high-performance hollandites. The stability of these ceramics under external electron irradiation, simulating the {beta} particles emitted by radioactive cesium, were also estimated, at the macroscopic and atomic scale. The point defects creation and their thermal stability were followed by electron paramagnetic resonance. (author)

  2. Transportable cesium irradiator (TPCI): Final safety analysis report: Revision 1

    International Nuclear Information System (INIS)

    This Final Safety Analysis Report describes the Transportable Cesium Irradiator (TPCI) and assesses the hazards associated with its operation. The TPCI consists of a mobile, lead-shielded, irradiation unit with support equipment mounted within an enclosed trailer. The irradiation unit has two basic compartments; a source chamber sized to mate with the transportation cask which houses the source capsules, and an irradiation chamber formed as a large shielded cylinder (drum) with a window. The irradiation chamber is mounted on a large diameter support bearing. As this chamber is rotated its window moves from the product access door, where produce is inserted or extracted, to a position in line with a similar window in the source chamber. When the windows are aligned the produce is irradiated, while the back wall of the irradiation chamber shields the product access door. The TPCI is designed to be transported throughout the continental United States. The transportation cask containing the cesium source capsules is transported separately from the irradiation unit and is installed when the TPCI unit has been readied for operation at a particular site. The transportation cask is a separate unit and is documented in a separate FSAR

  3. Morphological and electrical properties of zirconium vanadate doped with cesium

    Directory of Open Access Journals (Sweden)

    Marwa F. Elkady

    2014-09-01

    Full Text Available Cesium doped zirconium vanadate ZrV2O7 with different Cs dopant content (Cs/Zr varied from 0 to 0.5 in weight ratio were fabricated by hydrothermal technique at 120 °C for 60 min. The synthesized materials are thermally treated using microwave technique. The structural and morphological properties of the synthesized materials and thermally treated samples were investigated using XRD and SEM respectively. It was evident that all synthesized specimens have cubic phase structural without any extra phase but after heat treatment Orthorhombic phase appear with doped samples. However, the morphological structure of the doped synthesized materials has transferred from nanoparticles into rods aspect with heat treatment for the different dopant ratio. Moreover, the electrical properties of both the synthesized and thermally treated materials are studied by AC impedance measurements. The results indicated that the ionic conductivity of Cs-doped ZrV2O7 materials decreased by increasing the dopant ratio while that thermally treated samples the ionic conductivity increase by increasing the dopant ratio. Finally, the concentration of cesium dopants is found to play crucial role in tuning the morphology and electrical properties of nanostructures.

  4. A study of strontium and cesium sorption on granite

    International Nuclear Information System (INIS)

    The diffusion and sorption of cesium and strontium in crushed granite particles is discussed. Sorption experiments have been performed with one granite from Finnsjoen outside Forsmark on the east coast of Sweden and one granite from the Stripa mine in central Sweden. Granite samples have been crushed and screened, and six different particle size fractions from 0.10-0.12 mm to 4-5 mm of each rock have been used in the experiments. The initial concentrations of inactive cesium and strontium were 10-15 ppm. The experimental data indicate that the amount of sorption is dependent not only on the mass of granite particles, but also to some extent on the size of the particles. An attempt has been made to distinguish between sorption on external surfaces and inner surfaces. The amount of external surface adsorption was found to vary from 15-40 % of the total adsorption capacity for the particle size fraction 0.10-0.12 mm to a few percent or less for the largest particles used. (Auth.)

  5. Kelvin probe studies of cesium telluride photocathode for AWA photoinjector

    International Nuclear Information System (INIS)

    Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch (≈50nC) in a long bunch train. Here, we present a study of the work function of cesium telluride photocathode using the Kelvin probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the effect of UV exposure on the work function, and the evolution of the work function during and after photocathode rejuvenation via heating. -- Highlights: ► The correlation between Quantum Efficiency (QE) and work function. ► How QE and work function evolve together. ► Rejuvenation of the photocathode via heating and the effect on work function. ► The effects on the work function due to exposure to UV light

  6. Radiation doses resulting from incorporated radioactive cesium isotopes

    International Nuclear Information System (INIS)

    Age-dependent dose factors are given for inhaled or ingested cesium isotopes, which have been calculated on the basis of published data on the biokinetics of cesium in the human organism. Tabulated data are presented for Cs-129, Cs-130, Cs-131, Cs-132, Cs-134, Cs-135, Cs-136, Cs-137(+Ba-137m), and Cs-138. Comparison of results obtained for adults with relevant data published by the ICRP (1978), the NCRP (1977), and Schwarz (1982) shows very good agreement. More significant deviations are however found when comparing the results with data given in the Federal German Radiation Protection Ordinance, both with regard to adults and to infants, particularly refering to the lung data and to those for the gastro-intestinal tract and the skeleton. These discrepancies are primarily due to improved models developed since the time the Radiation Protection Ordinance has been issued, (respiratory and gastro-intestinal tracts), and to improvements achieved with the dosimetric concepts (calculation of dose for bone surfaces instead of the whole skeleton). The dose factors for newborn given by the publication in hand are significantly lower than those given in the Ordinance (for infants); this is a result of age-dependent retention functions having been considered for this publication. The reliability of the dose factor calculations for various ages, pregnant women and fetuses is discussed and quantified. (orig./HP)

  7. Kelvin probe studies of cesium telluride photocathode for AWA photoinjector

    Energy Technology Data Exchange (ETDEWEB)

    Wisniewski, Eric E., E-mail: ewisniew@anl.gov [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Velazquez, Daniel [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Yusof, Zikri, E-mail: zyusof@hawk.iit.edu [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Spentzouris, Linda; Terry, Jeff [Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Sarkar, Tapash J. [Rice University, 6100 Main, Houston, TX 77005 (United States); Harkay, Katherine [Accelerator Science Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States)

    2013-05-21

    Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch (≈50nC) in a long bunch train. Here, we present a study of the work function of cesium telluride photocathode using the Kelvin probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the effect of UV exposure on the work function, and the evolution of the work function during and after photocathode rejuvenation via heating. -- Highlights: ► The correlation between Quantum Efficiency (QE) and work function. ► How QE and work function evolve together. ► Rejuvenation of the photocathode via heating and the effect on work function. ► The effects on the work function due to exposure to UV light.

  8. Spectrally selective optical pumping in Doppler-broadened cesium atoms

    Institute of Scientific and Technical Information of China (English)

    Zhang Jun-Hai; Zeng Xian-Jin; Li Qing-Meng; Huang Qiang; Sun Wei-Min

    2013-01-01

    The D1 line spectrally selective pumping process in Doppler-broadened cesium is analyzed by solving the optical Bloch equations.The process,described by a three-level model with the A scheme,shows that the saturation intensity of broadened atoms is three orders of magnitude larger than that of resting atoms.The |Fg =3> → |Fe-4> resonance pumping can result in the ground state |Fg =4,mF =4> sublevel having a maximum population of 0.157 and the population difference would be about 0.01 in two adjacent magnetic sublevels of the hyperfine (HF) state Fg =4.To enhance the anisotropy in the ground state,we suggest employing dichromatic optical HF pumping by adding a laser to excite D1 line |Fg =4> → |Fe =3>transition,in which the cesium magnetometer sensitivity increases by half a magnitude and is unaffected by the nonlinear Zeeman effect even in Earth's average magnetic field.

  9. Diffusion of strontium, technetium, iodine and cesium in granitic rock

    International Nuclear Information System (INIS)

    The migration of strontium, technetium, iodine and cesium in granitic rock has been studied. Rock samples were taken from drilling cores in granitic and granodioritic rock, and small (2x2x2 cm) rock tablets from the drilling cores were exposed to a groundwater solution containing one of the studied elements at trace levels. The concentration of the element versus penetration depth in the rock tablet was measured radiometrically. The sorption on the mineral faces and the diffusion into the rock were studied by an autoradiographic technique. The cationic strontium and cesium have apparent diffusivities of 10-13 - 10-14 m2/s. The migration is confined to microfissures or filled fractures containing e.g., calcite, epidote or chlorite or in veins with high capacity minerals (e.g. biotite). The anionic iodine and technetium have apparent diffusivities of about 10-14 m2/s. These species migrate along mineral boundaries and in open fractures and to a minor extent in high capacity mineral veins. (orig.)

  10. Mobility of radioactive cesium in soil originated from the Fukushima Daiichi nuclear disaster. Application of extraction experiments

    International Nuclear Information System (INIS)

    Extraction experiments on soil radioactively contaminated by the Fukushima Daiichi Nuclear Power Plant accident were conducted by using a variety of extractants to acquire knowledge on the mobility of radioactive cesium in soil. The experimental results revealed that cesium is tightly bound with soil particles and that radioactive cesium newly deposited on soil due to the accident had apparently a higher mobility than stable cesium commonly existing in soil. The results suggested that radioactive cesium deposited on soil hardly migrates via aqueous processes, although chemical and mineralogical conditions of soil affect their mobility. (author)

  11. Inorganic ion exchangers. Application to liquid effluent processing

    International Nuclear Information System (INIS)

    Main inorganic ion exchangers used for radioactive liquid effluents presented in this report are: synthetic and natural zeolites, in titanium oxides, titanates, niobates, tantalates, zirconates, some insoluble salts of zirconium, molybdenum and tin, heteropolyacids and polyantimonic acid. Properties of these ion exchangers are described: structure, adsoption, radiation effects and thermal stability, application to waste processing, radioactive waste storage uranium and cesium 137 recovery are evoked

  12. A Reliable Hybrid Adsorbent for Efficient Radioactive Cesium Accumulation from Contaminated Wastewater

    Science.gov (United States)

    Awual, Md. Rabiul; Yaita, Tsuyoshi; Miyazaki, Yuji; Matsumura, Daiju; Shiwaku, Hideaki; Taguchi, Tomitsugu

    2016-01-01

    Cesium (Cs) removal from nuclear liquid wastewater has become an emerging issue for safeguarding public health after the accident at the Fukushima Daiichi Nuclear Power Plant. A novel macrocyclic ligand of o-benzo-p-xylyl-22-crown-6-ether (OBPX22C6) was developed and successfully immobilized onto mesoporous silica for the preparation of hybrid adsorbent. The benzene ring π electron is the part of crown ether of OBPX22C6 for easy orientation of the macrocyclic compound for making the π electron donation with Cs complexation. The potential and feasibility of the hybrid adsorbent as being Cs selective was evaluated in terms of sensitivity, selectivity and reusability. The results clarified that the Cs removal process was rapid and reached saturation within a short time. Considering the effect of competitive ions, sodium (Na) did not markedly affect the Cs adsorption whereas potassium (K) was slightly affected due to the similar ionic radii. However, the oxygen in long ethylene glycol chain in OBPX22C6 was expected to show strong coordination, including Cs-π interaction with Cs even in the presence of the high amount of K and Na. Due to its high selectivity and reusability, significant volume reduction is expected as this promising hybrid adsorbent is used for Cs removal in Fukushima wastewater.

  13. Copper ferrocyanide functionalized magnetic nanoparticles using polyelectrolyte for the removal of cesium

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hee Man; Lee, Kune Woo; Seo, Bum Kyoung; Moon, Jei Kwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    In the present study, magnetite nanoparticles were coated with copper ferrocyanide for the adsorption of radioactive Cs-137 in an aqueous solution through the grafting of polyethyleneimine. We describe the morphology, structure, and physical property of these nanoparticles. In addition, their ability to eliminate Cs-137 from water was also evaluated. Magnetic nanoadsorbents composed of a magnetic particles core and functional shell, which adsorb the contaminants, has attracted significant attention in environmental remediation owing to their high surface area and unique superparamagnetism. Since the nuclear accident at the Fukushima Daiichi nuclear power station in 2011, a huge amount of radioactive contaminants has been released into the environment. Among the various radioactive contaminants, cesium (Cs)-137 (137Cs) is the most apprehensive element owing to its long half-life (30.2 years), high solubility in water, and strong radiation emission in the form of gamma rays (γ-rays). Various methods such as ion exchange solvent extraction and precipitation are applied for the remediation of Cs-137 contaminated water. In particular, metal ferrocyanides show a high selectivity toward Cs-137. However, the very fine powder form of metal ferrocyanide causes a difficult separation from water through filtration.

  14. Fast concentration of dissolved forms of cesium radioisotopes from large seawater samples

    International Nuclear Information System (INIS)

    The method developed for cesium concentration from large freshwater samples was tested and adapted for analysis of cesium radionuclides in seawater. Concentration of dissolved forms of cesium in large seawater samples (about 100 L) was performed using composite absorbers AMP-PAN and KNiFC-PAN with ammonium molybdophosphate and potassium–nickel hexacyanoferrate(II) as active components, respectively, and polyacrylonitrile as a binding polymer. A specially designed chromatography column with bed volume (BV) 25 mL allowed fast flow rates of seawater (up to 1,200 BV h-1). The recovery yields were determined by ICP-MS analysis of stable cesium added to seawater sample. Both absorbers proved usability for cesium concentration from large seawater samples. KNiFC-PAN material was slightly more effective in cesium concentration from acidified seawater (recovery yield around 93 % for 700 BV h-1). This material showed similar efficiency in cesium concentration also from natural seawater. The activity concentrations of 137Cs determined in seawater from the central Pacific Ocean were 1.5 ± 0.1 and 1.4 ± 0.1 Bq m-3 for an offshore (January 2012) and a coastal (February 2012) locality, respectively, 134Cs activities were below detection limit (-3). (author)

  15. Development of cesium trapper and single-gas-bubble injector into sodium pool

    International Nuclear Information System (INIS)

    On the core disruptive accident in the sodium cooled fast breeder reactor, in fuel pins the cesium fission product with a high hazard is transferred to the sodium coolant together with noble gas including fission product, and the cesium accumulates on the cover gas area because of its low migration rate to sodium. The high temperature and high pressure in the cover gas due to the decay heat of fission products including cesium cause the leakage of cesium to the outside of reactor vessel. However the exact migration rate of cesium to sodium has not been reported because of difficulty on the evaluation of the interfacial area of large gas bubble (Minges et al., 1986). In this study, we developed a cesium trapper composed of β”-alumina cylindrical container and a single-gas-bubble injector without wettability. We confirmed that a single argon gas bubble was steadily produced in our injector. Bhaga proposed the bubble shape region map, which correlates the bubble shape with Reynolds number, Eotvos number and Morton number of the bubble ejected into sodium pool. The bubble shapes were estimated to be always ellipsoidal. We could successfully confirmed that the liquid sodium can be separated from liquid sodium cesium mixture by using β”-alumina, whose separation rate was found to be calculated by the Faraday's law of electrolysis. (author)

  16. Cesium-plasma-conductivity enhancement in the advanced thermionic energy converter. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Manikopoulos, C.N.

    Two methods of plasma conductivity enhancement in a cesium vapor thermionic energy converter have been studied. The first involved resonance photoabsorption of several cesium lines and the second utilized cesium plasma sustenance by application of microwave power. An extensive study of ionization processes in a cesium discharge in the presence of resonance ionization was made. Calculations were made of expected percentage excitation levels for several cesium resonance transitions for different values of neutral density and temperature as well as incident radiation power levels. The results of some of these computations were tabulated. Several ionization schemes were considered. A number of cesium transitions were investigated in the range of 799 to 870 nanometers for four different cesium reservoir temperatures, 467, 511, 550 and 591 K. The related absorption coefficients of the radiation lines in the plasma were deduced and tabulated. The resulting plasma conductivity increase was recorded and the associated ionization enhancement was deduced. A microwave cavity was built where the emitter and collector of a simple thermionic converter made up two of the cavity walls and resonant microwave power was externally applied. The I-V characteristics of the thermionic converter were studied under several microwave power levels in the range of 0 to 2 watts. Significant shifts to higher currents were observed as the microwave power levels were raised. In conclusion, both methods show promise as auxiliary ionization mechanisms for the thermionic energy converter, especially at low emitter temperatures.

  17. Cesium-plasma-conductivity enhancement in the advanced thermionic energy converter. Final report

    International Nuclear Information System (INIS)

    Two methods of plasma conductivity enhancement in a cesium vapor thermionic energy converter have been studied. The first involved resonance photoabsorption of several cesium lines and the second utilized cesium plasma sustenance by application of microwave power. An extensive study of ionization processes in a cesium discharge in the presence of resonance ionization was made. Calculations were made of expected percentage excitation levels for several cesium resonance transitions for different values of neutral density and temperature as well as incident radiation power levels. The results of some of these computations were tabulated. Several ionization schemes were considered. A number of cesium transitions were investigated in the range of 799 to 870 nanometers for four different cesium reservoir temperatures, 467, 511, 550 and 591 K. The related absorption coefficients of the radiation lines in the plasma were deduced and tabulated. The resulting plasma conductivity increase was recorded and the associated ionization enhancement was deduced. A microwave cavity was built where the emitter and collector of a simple thermionic converter made up two of the cavity walls and resonant microwave power was externally applied. The I-V characteristics of the thermionic converter were studied under several microwave power levels in the range of 0 to 2 watts. Significant shifts to higher currents were observed as the microwave power levels were raised. In conclusion, both methods show promise as auxiliary ionization mechanisms for the thermionic energy converter, especially at low emitter temperatures

  18. Equilibrium, kinetic and thermodynamic study of cesium adsorption onto nanocrystalline mordenite from high-salt solution.

    Science.gov (United States)

    Lee, Keun-Young; Park, Minsung; Kim, Jimin; Oh, Maengkyo; Lee, Eil-Hee; Kim, Kwang-Wook; Chung, Dong-Yong; Moon, Jei-Kwon

    2016-05-01

    In this study, the equilibrium, kinetics and thermodynamics of cesium adsorption by nanocrystalline mordenite were investigated under cesium contamination with high-salt solution, simulating the case of an operation and decommissioning of nuclear facilities or an accident during the processes. The adsorption rate constants were determined using a pseudo second-order kinetic model. The kinetic results strongly demonstrated that the cesium adsorption rate of nano mordenite is extremely fast, even in a high-salt solution, and much faster than that of micro mordenite. In the equilibrium study, the Langmuir isotherm model fit the cesium adsorption data of nano mordenite better than the Freundlich model, which suggests that cesium adsorption onto nano mordenite is a monolayer homogeneous adsorption process. The obtained thermodynamic parameters indicated that the adsorption involved a very stable chemical reaction. In particular, the combination of rapid particle dispersion and rapid cesium adsorption of the nano mordenite in the solution resulted in a rapid and effective process for cesium removal without stirring, which may offer great advantages for low energy consumption and simple operation. PMID:26683820

  19. Caesium absorption by barley - influence of its retention by the soil - competitive action of potassium; Absorption du cesium par l'orge - influence de sa retention dans le sol - action competitive du potassium

    Energy Technology Data Exchange (ETDEWEB)

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

    1964-06-01

    . Par ailleurs, l'ion K{sup +} n'a concurrence l'absorption de Cs{sup +} par l'orge en milieux de culture sur solution nutritive et sur sol, que jusqu'a des doses relativement faibles de potassium, de l'ordre de l'optimum nutritif. Ceci montre que l'addition de potassium a un milieu deja riche en cet element ne reduit plus l'absorption de cesium par l'orge. Le choix de conditions experimentales proches des conditions naturelles (milieux nutritifs a dominante de calcium) et l'examen de la distribution du cesium radioactif entre sol, solution du sol et plante en presence de tres petites doses de cesium stable, conferent a ces resultats un interet 'hygiene atomique': on doit s'attendre a un risque de contamination certain pour les vegetaux cultives sur milieux synthetiques et pour les vegetaux croissant sur des sols inondes tels que le riz et le cresson. Mais le cesium radioactif incorpore sans entraineur a un sol de capacite d'echange moyenne (de l'ordre de 150 milliequivalents par kg) presente relativement peu de danger, du fait de la dependance etroite entre le prelevement de Cs radioactif du sol par les plantes et sa retention dans le sol. Nos experiences nous ont permis en outre d'examiner la valeur des moyens de decontamination partielle d'un sol proposes par certains atomistes: de meme que la dilution isotopique se revele totalement inefficace sous cet angle, l'apport de sels de potasse en quantite depassant l'optimum nutritif se revele incapable de reduire l'absorption de cesium radioactif par la plante.

  20. Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

    Science.gov (United States)

    Brombin, M.; Spolaore, M.; Serianni, G.; Pomaro, N.; Taliercio, C.; Palma, M. Dalla; Pasqualotto, R.; Schiesko, L.

    2014-11-01

    A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors' holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

  1. Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

    International Nuclear Information System (INIS)

    A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors’ holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns

  2. Langmuir probes for SPIDER (source for the production of ions of deuterium extracted from radio frequency plasma) experiment: Tests in BATMAN (Bavarian test machine for negative ions)

    Energy Technology Data Exchange (ETDEWEB)

    Brombin, M., E-mail: matteo.brombin@igi.cnr.it; Spolaore, M.; Serianni, G.; Pomaro, N.; Taliercio, C.; Palma, M. Dalla; Pasqualotto, R. [Consorzio RFX, Corso Stati Uniti 4, I-35127 Padova (Italy); Schiesko, L. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany)

    2014-11-15

    A prototype system of the Langmuir probes for SPIDER (Source for the production of Ions of Deuterium Extracted from RF plasma) was manufactured and experimentally qualified. The diagnostic was operated in RF (Radio Frequency) plasmas with cesium evaporation on the BATMAN (BAvarian Test MAchine for Negative ions) test facility, which can provide plasma conditions as expected in the SPIDER source. A RF passive compensation circuit was realised to operate the Langmuir probes in RF plasmas. The sensors’ holder, designed to better simulate the bias plate conditions in SPIDER, was exposed to a severe experimental campaign in BATMAN with cesium evaporation. No detrimental effect on the diagnostic due to cesium evaporation was found during the exposure to the BATMAN plasma and in particular the insulation of the electrodes was preserved. The paper presents the system prototype, the RF compensation circuit, the acquisition system (as foreseen in SPIDER), and the results obtained during the experimental campaigns.

  3. Cesium and strontium exchange by the framework potassium titanium silicate K3HTi4O4(SiO4)3 x 4H2O

    International Nuclear Information System (INIS)

    Potassium titanium silicate with a semicrystalline framework of the formula K3HTi4O4(SiO4)3 x 4H2O has been prepared under mild hydrothermal conditions and its protonic form, H4Ti4O4(SiO4)3 x 8H2O, was obtained by acid treatment of the potassium compound. A comparative ion exchange testing of the H4Ti4O4(SiO4)3 x 8H2O towards alkali and alkaline earth metals in a broad pH and concentration range was carried out. It was found that potassium titanium silicate is a moderately weak cation exchanger, possessing high ion exchange capacity (up to 4-5 meq/g) and showing preference for heavy alkali and alkaline earth metals uptake. The selectivity of K3HTi4O4(SiO4)3 x 4H2O towards Cs+ and Sr2+ ions in alkaline and acid media in the presence of competitive inorganic ions and certain organic compounds was also studied. The data obtained suggest that despite the existence of well defined tunnel structure with parameters fitting for cesium ion in the K3HTi4O4(SiO4)3 x 4H2O, potassium titanium silicate could remove cesium (and strontium) efficiently only under some specific conditions, namely, at pH close to neutral and in the absence of competitive ions and especially of organic complexing agents. (author)

  4. A New Pumping-Probing Scheme for the Optically Pumped Cesium Beam Frequency Standard

    Institute of Scientific and Technical Information of China (English)

    陈景标; 朱程锦; 王凤芝; 杨东海

    2001-01-01

    A new pumping-probing scheme for the optically pumped cesium beam frequency standard has been experimentally tested in our laboratory. The stability of the optically pumped cesium beam frequency standard was measured by comparing its 10 MHz output with an HP5071A commercial cesium atomic clock. The result shows that the frequency stability for the 1 s and 30000s sample times are 1.2 × 10-11 and 3.7 × 10-13, respectively. It was proved that the new pumping scheme works well.

  5. Application of Cesium isotopes in daily life; Aplicacoes dos isotopos do Cesio no cotidiano

    Energy Technology Data Exchange (ETDEWEB)

    Jordao, B.O.; Quaresma, D.S.; Carvalho, R.J., E-mail: bjordan@on.br, E-mail: dansq@on.br, E-mail: carvalho@on.br [Observatorio Nacional (ON/LPTF), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Tempo e Frequencia; Peixoto, J.G.P., E-mail: guilherm@ird.gov.br [Instituto de Radioprotecao e Dosimetria, (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. de Metrologia das Radiacoes Ionizantes

    2014-07-01

    In the world of science, the desire of the scientific community to discover new chemical elements is crucial for the development of new technologies in various fields of knowledge. And the main chemical element addressed by this article is Cesium, but specifically {sup 133}Cesium isotope and radioisotope {sup 137}Cesium, exemplifying their physical and chemical characteristics, and their applications. This article will also show how these isotopes have provided researchers a breakthrough in the field of radiological medicine and in time and frequency metrology. (author)

  6. Specific interaction of cesium with the surface of calcium silicate hydrates

    International Nuclear Information System (INIS)

    The sorption of cesium at the calcium silicate hydrates (CSH) surface was investigated, both through sorption isotherm data and by solid-state NMR experiments. The sorption ability of CSH towards cesium is favored for low solid Ca/Si molar ratios, in agreement with the negative surface charge they develop then. A significant proportion of these sorbed cesium cations remains tightly bound to the surface sites forming, in dehydrated CSH, inner-sphere complexes, which can not be removed by alcohol washing. Chloride seems to present a lower affinity for CSH, even for high Ca/Si molar ratios, where the surface charge becomes positive. (orig.)

  7. Test procedures and instructions for single shell tank saltcake cesium removal with crystalline silicotitanate

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, J.B.

    1997-01-07

    This document provides specific test procedures and instructions to implement the test plan for the preparation and conduct of a cesium removal test, using Hanford Single Shell Tank Saltcake from tanks 24 t -BY- I 10, 24 1 -U- 108, 24 1 -U- 109, 24 1 -A- I 0 1, and 24 t - S-102, in a bench-scale column. The cesium sorbent to be tested is crystalline siticotitanate. The test plan for which this provides instructions is WHC-SD-RE-TP-024, Hanford Single Shell Tank Saltcake Cesium Removal Test Plan.

  8. Investigation of adsorption and wetting of 3He on cesium and cesiated glass

    International Nuclear Information System (INIS)

    Experiments have been carried out to investigate the binding of 3He on cesium substrates, using optical pumping to spin-polarize the atoms. The behavior of 3He on the walls at low temperature can be analyzed through the evolution of the nuclear magnetization of the sample. Preliminary results are presented, including: (1) adsorption studies of gaseous 3He on cesiated glass; (2) magnetic relaxation time of polarized liquid 3He on cesium and cesiated glass; (3) evidence for wetting of liquid 3He on cesium. 8 refs., 2 figs

  9. Selective cesium removal from radioactive liquid waste by crown ether immobilized new class conjugate adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Awual, Md. Rabiul, E-mail: awual.rabiul@jaea.go.jp [Actinide Coordination Chemistry Group, Quantum Beam Science Centre (QuBS), Japan Atomic Energy Agency (SPring-8), Hyogo 679-5148 (Japan); Yaita, Tsuyoshi [Actinide Coordination Chemistry Group, Quantum Beam Science Centre (QuBS), Japan Atomic Energy Agency (SPring-8), Hyogo 679-5148 (Japan); Taguchi, Tomitsugu [Nano-Structure Synthesis Research Group, Quantum Beam Science Centre (QuBS), Japan Atomic Energy Agency, Tokai-mura, Ibaraki-ken 319-1195 (Japan); Shiwaku, Hideaki; Suzuki, Shinichi; Okamoto, Yoshihiro [Actinide Coordination Chemistry Group, Quantum Beam Science Centre (QuBS), Japan Atomic Energy Agency (SPring-8), Hyogo 679-5148 (Japan)

    2014-08-15

    Graphical abstract: - Highlights: • DB24C8 crown ether was functionalized for preparation of conjugate adsorbent. • Radioactive {sup 137}Cs can be selectively removed by the conjugate adsorbent. • Adsorbent can effectively capture Cs even in the presence of a high amount Na and K. • Adsorbent is reversible and able to be reused without significant deterioration. - Abstract: Conjugate materials can provide chemical functionality, enabling an assembly of the ligand complexation ability to metal ions that are important for applications, such as separation and removal devices. In this study, we developed ligand immobilized conjugate adsorbent for selective cesium (Cs) removal from wastewater. The adsorbent was synthesized by direct immobilization of dibenzo-24-crown-8 ether onto inorganic mesoporous silica. The effective parameters such as solution pH, contact time, initial Cs concentration and ionic strength of Na and K ion concentrations were evaluated and optimized systematically. This adsorbent was exhibited the high surface area-to-volume ratios and uniformly shaped pores in case cavities, and its active sites kept open functionality to taking up Cs. The obtained results revealed that adsorbent had higher selectivity toward Cs even in the presence of a high concentration of Na and K and this is probably due to the Cs–π interaction of the benzene ring. The proposed adsorbent was successfully applied for radioactive Cs removal to be used as the potential candidate in Fukushima nuclear wastewater treatment. The adsorbed Cs was eluted with suitable eluent and simultaneously regenerated into the initial form for the next removal operation after rinsing with water. The adsorbent retained functionality despite several cycles during sorption-elution-regeneration operations.

  10. Selective cesium removal from radioactive liquid waste by crown ether immobilized new class conjugate adsorbent

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • DB24C8 crown ether was functionalized for preparation of conjugate adsorbent. • Radioactive 137Cs can be selectively removed by the conjugate adsorbent. • Adsorbent can effectively capture Cs even in the presence of a high amount Na and K. • Adsorbent is reversible and able to be reused without significant deterioration. - Abstract: Conjugate materials can provide chemical functionality, enabling an assembly of the ligand complexation ability to metal ions that are important for applications, such as separation and removal devices. In this study, we developed ligand immobilized conjugate adsorbent for selective cesium (Cs) removal from wastewater. The adsorbent was synthesized by direct immobilization of dibenzo-24-crown-8 ether onto inorganic mesoporous silica. The effective parameters such as solution pH, contact time, initial Cs concentration and ionic strength of Na and K ion concentrations were evaluated and optimized systematically. This adsorbent was exhibited the high surface area-to-volume ratios and uniformly shaped pores in case cavities, and its active sites kept open functionality to taking up Cs. The obtained results revealed that adsorbent had higher selectivity toward Cs even in the presence of a high concentration of Na and K and this is probably due to the Cs–π interaction of the benzene ring. The proposed adsorbent was successfully applied for radioactive Cs removal to be used as the potential candidate in Fukushima nuclear wastewater treatment. The adsorbed Cs was eluted with suitable eluent and simultaneously regenerated into the initial form for the next removal operation after rinsing with water. The adsorbent retained functionality despite several cycles during sorption-elution-regeneration operations

  11. Determinations of cesium-134, cesium-137 and potassium-40 as a measure of intrauterine exposure to rays and contamination of human milk after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    In order to gain better insights into the degree of intrauterine exposure to rays after the Chernobyl reactor accident, placental measurements of the activity levels of cesium-134 and cesium-137 were carried out in 125 expectant mothers from the Munich area using four thallium-activated sodium iodine crystal detectors. The lower limit of detection determined for this technique was 1-2 bq/kg. Parallel tests were performed on human milk samples to establish their contents of cesium-137 and potassium-40. The ultrapure germanium detector used for this purpose measured levels down to a detection threshold of 1 bq/l. In a total of 13 placentae (10 %) and 56 milk samples (57%) the activity of cesium-137 was found to be so low as to preclude detection. The highest values measured were 18.6 bq/kg for the placentae and 10.6 bq/l for the milk samples. The activity concentrations of potassium-40 were frequently seen to exceed those of cesium-137, the highest value determined here being 73.6 bq/l. The author has come to the conclusion that the alleged increases in radiation levels remain within the range of variations generally expected to occur with natural radiation. Mothers are not discouraged from breast-feeding, even though their attention must be drawn to the fact that the rates of malignant diseases and genetic damage tend to rise on a global scale. (KST)

  12. Diffusion of water, cesium and neptunium in pores of rocks

    International Nuclear Information System (INIS)

    Teollisuuden Voima Oy (TVO) is investigating the feasibility to dispose of spent nuclear fuel within Finland. The present plan calls for the repository to be located in crystalline rock at a depth of several hundred meters. The safety assessment of the repository includes calculations of migration of waste nuclides. The flow of waste elements in groundwater will be retarded through sorption interaction with minerals and through diffusion into rock. Diffusion is the only mechanism retarding the migration of non-sorbing species and, it is expected to be the dominating retardation mechanism of many of the sorbing elements. In the investigation the simultaneous diffusion of tritiated water (HTO), cesium and neptunium in rocks of TVO investigation sites at Kivetty, Olkiluoto and Romuvaara were studied. (11 refs., 33 figs., 9 tabs.)

  13. Cesium-137 accident lessons in Goiania, Goias State, Brazil

    International Nuclear Information System (INIS)

    This document relates the experience obtained by several professionals which had an important role in the cesium-137 accident occurred in Goiania, Goias State, Brazil in September, 1987. It's divided into chapters, according to the action area - medical, nursing, social assistance, odontological and psychological. At first, some notions of radioprotection are explained, followed by the accident history and by the doctors and nurses action during the emergency phase and the medical, odontological, social and psychological assistance to the victims. The social assistance report shows some statistical data about the economic, occupational and social conditions of the accident victims. It is shown some information about the health institutions and the sanitary care in the ionizing radiation and about the occupational radiological protection in Goiania

  14. Coherence properties of nanofiber-trapped cesium atoms

    CERN Document Server

    Reitz, D; Mitsch, R; Schneeweiss, P; Rauschenbeutel, A

    2013-01-01

    We experimentally study the ground state coherence properties of cesium atoms in a nanofiber-based two-color dipole trap, localized 200 nm away from the fiber surface. Using microwave radiation to coherently drive the clock transition, we record Ramsey fringes as well as spin echo signals and infer a reversible dephasing time $T_2^\\ast=0.6$ ms and an irreversible dephasing time $T_2^\\prime=3.7$ ms. By theoretically modelling the signals, we find that, for our experimental parameters, $T_2^\\ast$ and $T_2^\\prime$ are limited by the finite initial temperature of the atomic ensemble and the heating rate, respectively. Our results represent a fundamental step towards establishing nanofiber-based traps for cold atoms as a building block in an optical fiber quantum network.

  15. Coherence Properties of Nanofiber-Trapped Cesium Atoms

    Science.gov (United States)

    Reitz, D.; Sayrin, C.; Mitsch, R.; Schneeweiss, P.; Rauschenbeutel, A.

    2013-06-01

    We experimentally study the ground state coherence properties of cesium atoms in a nanofiber-based two-color dipole trap, localized ˜200nm away from the fiber surface. Using microwave radiation to coherently drive the clock transition, we record Ramsey fringes as well as spin echo signals and infer a reversible dephasing time of T2*=0.6ms and an irreversible dephasing time of T2'=3.7ms. By modeling the signals, we find that, for our experimental parameters, T2* and T2' are limited by the finite initial temperature of the atomic ensemble and the heating rate, respectively. Our results represent a fundamental step towards establishing nanofiber-based traps for cold atoms as a building block in an optical fiber quantum network.

  16. Trade study for the disposition of cesium and strontium capsules

    International Nuclear Information System (INIS)

    This trade study analyzes alternatives for the eventual disposal of cesium and strontium capsules currently stored at the Waste Encapsulation and Storage Facility as by-product. However, for purposes of this study, it is assumed that at some time in the future, the capsules will be declared high-level waste and therefore will require disposal at an offsite geologic repository. The study considered numerous alternatives and selected three for detailed analysis: (1) overpack and storage at high-level waste canister storage building, (2) overpack at the high-level waste vitrification facility followed by storage at a high-level waste canister storage building, and (3) blend capsule contents with other high-level waste feed streams and vitrify at the high-level waste vitrification facility

  17. Norbadione A: synthetic approach and cesium complexation studies

    International Nuclear Information System (INIS)

    This work was dedicated to the study of the synthesis and complexation studies of norbadione A: a pigment originating from a mushroom. A synthetic approach, based on a double Suzuki-Miyaura coupling, was developed. This strategy was applied with high yields to the synthesis of various norbadione A analogues, as well as to the synthesis of simple pulvinic acids. Access to functionalized precursors of the molecule was also studied and the final coupling remains to be done. Besides, a speciation study based on electro-spray ionization mass spectrometry was conducted with norbadione A and one of the analogues. This study allowed the assessment of the cesium complexation abilities of each molecule. Structural data was also obtained and complexation constants were calculated. Finally, norbadione A and various synthetic products have been tested via high-throughput screening methods and strong antioxidant properties were observed. Other biological results are also reported. (author)

  18. Comparative study of cesium adsorption on dioctahedral and trioctahedral smectites

    International Nuclear Information System (INIS)

    Bentonites which are characterized by good rheological, mineralogical and chemical stability is considered used as sealing barriers in multibarrier Slovak system of deep geological repository for high-level radioactive waste and spent nuclear fuel. In Slovak Republic there are several significant deposits of bentonite, which are characterized by appropriate adsorption properties and meet the geotechnical requirements for this type of barriers. Study of adsorption properties of bentonites and other smectites is an essential step for developing the migration model long-lived corrosion and activation products, and fission products of uranium. Nuclear wastes contain the most important nuclear fission products, radioisotopes 134Cs and 137Cs. The present paper investigates and compares the cesium adsorption properties of Slovak and North America bentonites composed mainly of dioctahedral smectite montmorillonite (J, L, SAz-1 and STx-1) and trioctahedral smectites saponite (SapCa-2) and hectorite (SHCa-1). (author)

  19. Quality assurance program plan for cesium legacy project

    International Nuclear Information System (INIS)

    This Quality Assurance Program Plan (QAPP) provides information on how the Quality Assurance Program is implemented for the Cesium Legacy Project. It applies to those items and tasks which affect the completion of activities identified in the work breakdown structure of the Project Management Plan (PMP). These activities include all aspects of cask transportation, project related operations within the 324 Building, and waste management as it relates to the specific activities of this project. General facility activities (i.e. 324 Building Operations, Central Waste Complex Operations, etc.) are covered in other appropriate QAPPs. The 324 Building is currently transitioning from being a Pacific Northwest National Laboratory (PNNL) managed facility to a B and W Hanford Company (BWHC) managed facility. During this transition process existing PNNL procedures and documents will be utilized until replaced by BWHC procedures and documents

  20. Quantitative analysis of cesium in synthetic lithium molten salts

    International Nuclear Information System (INIS)

    An analytical technique for fission products in lithium molten salts of spent PWR (Pressurized Water Reactor) fuels has been studied for the establishment of optimum chemical engineering process and the evaluation of process material balance in developing Direct Oxide Reduction Process with lithium metal. As part of the basic research, synthetic dissolver solutions of lithium chloride containing trace amounts of fission product elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Y, Cs, Ru, Rh, Pd, Mo, Zr, Cd, Ba, Sr, Te and Se) was prepared and used in establishing the selective separation technique of cesium from lithium chloride matrix using cation exchange chromatography. Its recovery was measured by flame atomic absorption spectrometry and the reliability of this technique was evaluate

  1. Vector Cesium Magnetometer for the nEDM Experiment

    International Nuclear Information System (INIS)

    Full text: We use optical pumping combined with magnetic resonance in a Cesium vapor cell in order to measure the magnetic field. A Vector Cs Magnetometer uses multiple laser beams to follow the dynamics of the spin in 3D. The 3D signal is used to extract the Larmor frequency of the spins, and to extract the direction of the magnetic field through the path of the spins. The magnetometer was successfully tested in a proof of principle experiment. Its measured performance is ∼50 pT/Hz1/2 for the directions perpendicular to the magnetic field, and ∼500 fT/Hz1/2 for the direction parallel to the magnetic field. (author)

  2. Cesium and strontium sorption behavior in amended agricultural soils

    Science.gov (United States)

    Mehmood, Khalid; Hofmann, Diana; Burauel, Peter; Vereecken, Harry; Berns, Anne E.

    2014-05-01

    Biogas digestates and biochar are emerging soil amendments. Biochar is a byproduct of pyrolysis process which is thermal decomposition of biomass to produce syngas and bio-oil. The use of biochar for soil amendment is being promoted for higher crop yields and carbon sequestration. Currently, the numbers of biogas plants in Germany are increasing to meet the new energy scenarios. The sustainability of biogas industry requires proper disposal options for digestate. Biogas digestates being rich in nutrients are beneficial to enhance agricultural productions. Contrary to the agronomical benefits of these organic amendments, their use can influence the mobility and bioavailability of soil contaminants due to nutrients competition and high organic matter content. So far, the impact of such amendments on highly problematic contaminants like radionuclides is not truly accounted for. In the present study, sorption-desorption behavior of cesium and strontium was investigated in three soils of different origin and texture. Two agricultural soils, a loamy sand and a silty soil, were amended with biochar and digestate in separate experiments, with field application rates of 25 Mg/ha and 34 Mg/ha, respectively. For comparison a third soil, a forest soil, was incubated without any amendment. The amendments were mixed into the top 20 cm of the field soils, resulting in final concentrations of 8-9 g biochar/Kg soil and 11-12 g digestate/Kg soil. The soils were incubated for about six months at room temperature. Sorption-desorption experiments were performed with CsCl and SrCl2 after pre-equilibrating the soils with CaCl2 solutions. The amendments with field application rates did not have a significant effect on the relevant soil parameters responsible for the sorption behavior of the two radionuclides. Comparatively, the soil type lead to distinctive differences in sorption-desorption dynamics of the two radionuclides. Cesium showed a higher affinity for silty soil followed by

  3. Elastic scattering of sodium and cesium atoms at ultracold temperatures

    Institute of Scientific and Technical Information of China (English)

    Zhang Ji-Cai; Wang Ke-Dong; Liu Yu-Fang; Sun Jin-Feng

    2011-01-01

    The elastic scattering properties in a mixture of sodium and cesium atoms are investigated at cold and ultracold temperatures. Based on the accurate interatomic potential for the NaCs mixture,the interspecies s-wave scattering lengths,the effective ranges and the p-wave scattering lengths are calculated by the quantal method and the semiclassical method,respectively. The s-wave scattering lengths are 512.7ao for the singlet state and 33.4ao for the triplet state. In addition,the spin-change and elastic cross sections are also calculated,and the g-wave shape resonance is found in the total elastic cross sections.

  4. Hot demonstration of proposed commercial cesium removal technology: Progress report

    International Nuclear Information System (INIS)

    Cesium, strontium, and technetium radionuclides constitute a small fraction of the primarily sodium and potassium salts present in supernatants that are being stored in tanks at Hanford, Oak Ridge, Savannah River, and Idaho and must be remediated. Nuclide removal technologies supplied by the US Department of Energy Office of Science and Technology's Efficient Separations and Processing (ESP) Cross-Cutting Program have been previously proposed and tested in small batch and column tests using both simulated and actual supernatants. These technologies must now be tested and the most appropriate ones selected using a flow system of a scale suitable to obtain engineering data that can be applied to the design of pilot-scale equipment. This report describes the operation of the experimental test unit that is located in Building 4501 (ORNL) and the results using the sorbent materials that were tested

  5. Negative ion based neutral beam injector for JT-60U

    Science.gov (United States)

    Okumura, Y.; Araki, M.; Hanada, M.; Inoue, T.; Kunieda, S.; Kuriyama, M.; Matsuoka, M.; Mizuno, M.; Ohara, Y.; Tanaka, M.; Watanabe, K.

    1992-10-01

    A 500 keV, 10 MW neutral beam injector is to be constructed in JT-60 Upgrade for the experiments of current drive and heating of heat density core plasmas. This is the first neutral beam injector in the world using negative ions as the primary ions. In the design, D- ion beams of 44 A, 500 keV are produced by two ion sources (22 A/each ion source) and neutralized in a long gas neutralizer. The total system efficiency is about 40%. The ion source is a cesium-seeded multicusp volume source having a three stage electrostatic accelerator. To reduce the stripping loss of D- ions in the accelerator, the ion source should be operated at a low pressure of 0.3 Pa with a current density of 13 mA/cm2. The first test of the full-size negative ion source is scheduled from middle of 1993.

  6. The sputter generation of negative ion beams

    International Nuclear Information System (INIS)

    A brief review is given of recent progress toward a quantitative understanding of negative ion formation by sputtering from surfaces covered with fractional layers of highly electropositive adsorbates. Practical models developed for estimating changes in work functions Δφ by electropositive adsorbates are described. The secondary negative ion generation process is examined through the use of composite energy/velocity dependent analytical models. These models are used to illustrate the effect of work function on the energy distributions of negative ions sputter ejected from a polycrystalline molybdenum surface covered with fractional layers of cesium. Predictions are also made of the functional dependence of the probability for negative ion formation on cesium coverage. The models predict energy distributions which are in basic disagreement with experimental observations, implying their inappropriateness for describing the sputter negative ion generation process. We have also developed a model for calculating sputter ratios based on the use of simple scaling procedures to bring Sigmund theory into close agreement with experimental observation accounting for the threshold effect. Scaling factors for projectile energies E > 1000 eV are found to be independent of energy while those for projectile energies Eth < E < 1000 eV were found to be energy dependent. In this study, the model and scaling techniques utilized to bring Sigmund theory into agreement with experiment are discussed in detail and several examples provided which illustrate the versatility, accuracy and utility of the model. In the present report, we describe the model and apply it to the case of sputtering a selected number of metals with energetic cesium ions. In particular, we present sputter ratio information for a number of Cs-projectile/metal-target combinations; the targets are bombarded at normal incidence to the surface

  7. Safety analysis report for packaging (onsite) for the Waste Encapsulation and Storage Facility ion exchange module

    International Nuclear Information System (INIS)

    The Waste Encapsulation and Storage Facility (WESF) is in need of providing an emergency ion exchange system to remove cesium or strontium from the pool cell in the event of a capsule failure. The emergency system is call the WESF Emergency Ion Exchange System and the packaging is called the WESF ion exchange module (WIXM). The packaging system will meet the onsite transportation requirements for a Type B, highway route controlled quantity package as well as disposal requirements for Category 3 waste

  8. Removal and adsorption of radioactive cesium from contaminated soil caused by the Fukushima Daiichi Nuclear Power Station accident

    International Nuclear Information System (INIS)

    The removal and adsorption of radioactive cesium, 137Cs or 134Cs, from contaminated soil was investigated using various extractants: sodium hydroxide, hydrochloric acid, and sulfuric acid. In this experiment, a sand sample was used as contaminated soil. Although the radioactive cesium could not be removed from the soil by using sodium hydroxide, 64% of the removal efficiency was provided at room temperature when 10 M hydrochloric acid was used. Eighty percent of the radioactive cesium was removed by using 1 M sulfuric acid containing 0.1 M thiourea at 90℃. A more than 90% removal efficiency was obtained by increasing of the volume of sulfuric acid containing thiourea. The same result was obtained using custom-made radioactive cesium removal equipment. The adsorption of the radioactive cesium was also investigated. In an experiment of concerning adsorption, contaminated water containing radioactive cesium was prepared from a contaminated sand sample. More than 96% adsorption was obtained using zeolite (clinoptilolite). However, when commercial activated carbon was used, most the radioactive cesium was hardly removed. The influence of shaking time on the adsorption of radioactive cesium was investigated by a batch-system using zeolite. As a result, a shaking time of at least 5 min showed that the radioactive cesium was quantitatively adsorbed to zeolite. The adsorptive behavior of the radioactive cesium by a flow-system was also examined using zeolite. (author)

  9. Hypothesis for the mechanism of negative ion production in the surface-plasma negative hydrogen ion source

    International Nuclear Information System (INIS)

    An analysis of the surface-plasma negative hydrogen ion source has shown that the tungsten cathode supports approximately a monolayer of cesium. The backscattering of protons from the cathode as energetic neutrals and the subsequent backscattering of these neutrals from the anode provides for a flux of energetic atoms incident upon the cathode which is comparable to the ion flux. A hypothesis is proposed for the generation of negative ions during the collision of these energetic atoms with the cathode. Several mechanisms for negative ion production by proton collision with the surface are discussed. (U.S.)

  10. Cesium-137 in Lake Michigan sediments: areal distribution and correlation with other man-made materials

    International Nuclear Information System (INIS)

    Grab samples of sediment were collected at 530 locations in Lake Michigan, primarily in the southeastern quarter of the lake. Each sample was analysed in the field and in the laboratory for fallout cesium-137. Twenty-five of the samples collected near the mouth of the St. Joseph River, were also analysed in the laboratory for 11 other man-made materials known to be discharged into the river. Two statistical methods were used to determine if cesium-137 can be used as an environmental tracer to predict the areal distributions of other man-made materials. The results show fallout cesium-137 to be a moderate to good tracer for locating areas of accumulation of plutonium-238, plutonium-239, zinc, copper, chromium, lead, dieldrin, DDT and PCB in sediment. Little or no correlation is found between fallout cesium-137 and strontium-90 or nickel. (author)

  11. Candlestick oven with a silica wick provides an intense collimated cesium atomic beam

    Science.gov (United States)

    Pailloux, A.; Alpettaz, T.; Lizon, E.

    2007-02-01

    This article shows that readily available glass and silica fibers and braids are suitable capillary structure for recirculating ovens, such as candlestick ovens, becoming then an alternative wick material to conventional metal based capillary structures. In order to study wettability and capillarity of metallic liquid cesium on borosilicate and silica microstructures, samples were selected, prepared, and tested experimentally. The contact angle of cesium on silica glass was roughly measured: θ =35°±10°. A commercially available silica braid was then introduced inside a candlestick oven to transfer the metallic liquid cesium from the cold reservoir to the hot emission point of the candlestick. A collimated cesium atomic beam of intensity of 2×1016at./ssr was obtained, stable and reproducible. Furthermore, this modified oven is easy to handle daily.

  12. Assessment of food calcium radioprotection effectiveness against cesium-137, added alone and with iodine-131

    International Nuclear Information System (INIS)

    New fish product with addition of food calcium had radioprotective properties, resulted in decreased cesium-137 content in organs and tissues of animals by 40-60% and lesser changes in differential blood count and biochemical indexes of blood serum

  13. Removal of cesium from low level waste solutions by copper hexacyanoferrate loaded resins

    International Nuclear Information System (INIS)

    Sorbents for the separation of radio cesium from aqueous solutions were synthesized by incorporating copper hexacyanoferrate (II) in the matrix of anion exchange resins of Indian origin, viz. Indion-810 and Tulsion-A27MP. Their efficiency for the cesium removal was tested under both static and dynamic conditions. The resins were found to be highly selective for radio cesium from a variety of salt and acid solutions. In general, Tulsion-based resins showed more tolerance towards chemical load in the solutions than the other. Pilot column run with Indion-based loaded resin showed that it effectively removed all the cesium activity from few thousands of litres of mixed low level waste streams from reactors, fuel reprocessing plant and nuclear laboratories. (author). 24 refs., 2 figs., 3 tabs

  14. Biological effects of cesium-137 injected in beagle dogs of different ages

    Energy Technology Data Exchange (ETDEWEB)

    Nikula, K.J.; Muggenburg, B.A.; Griffith, W.C. [and others

    1995-12-01

    The toxicity of cesium-137 ({sup 137}Cs) in the Beagle dog was investigated at the Argonne National Laboratory (ANL) as part of a program to evaluate the biological effects of internally deposited radionuclides. The toxicity and health effects of {sup 137}Cs are important to understand because {sup 137}Cs is produced in large amounts in light-water nuclear reactors. Large quantities of cesium radioisotopes have entered the human food chain as a result of atmospheric nuclear weapons test, and additional cesium radioisotopes were released during the Chernobyl accident. Although the final analyses are not complete, three findings are significant: older dogs dies significantly earlier than juvenile and young adult dogs; greater occurrence of sarcomas in the cesium-137 injected dogs; the major nonneoplastic effect in dogs surviving beyond 52 d appears to be testicular atrophy.

  15. Total deposition of cesium-137 measured in Finland during the exercise `RESUME 95` in August 1995

    Energy Technology Data Exchange (ETDEWEB)

    Geer, L.E. De; Vintersved, I.; Arntsing, R. [National Defence Research Establisment, Nuclear Detection Group, Stockholm (Sweden)

    1997-12-31

    In the exercise called `RESUME 95` the Nuclear Detection Group from the National Defence Research Establishment in Stockholm participated with field gamma ray measurements combined with soil sampling and profile measurements. The results are presented in this report for the measurements of cesium-137. We considered the measurements of cesium-137 at the airfield the most important part of the in-situ exercise. Data was of course collected also for cesium-134 and natural radionuclides but time has not permitted a full analysis of these radionuclides. The methodology would, however, be the same as applied for cesium-137. Less attention was paid for area II and due to limited personnel resources the search exercise was not fully carried out. (au).

  16. Cs2 ‘diffuse bands’ emission from superheated cesium vapor

    Science.gov (United States)

    Pichler, G.; Makdisi, Y.; Kokaj, J.; Thomas, N.; Mathew, J.; Beuc, R.

    2016-07-01

    Thermal emission from superheated cesium vapor was studied to very high temperatures from 700 °C to 1000 °C. This was performed in the vapor condition only and with no liquid cesium present in the all-sapphire cell. We observed a number of atomic and molecular spectral features simultaneously in emission and absorption, especially peculiar thermal emission of cesium dimer diffuse bands (2 3Πg → a 3∑u + transitions) around 710 nm coexisting with absorption bands around first resonance lines at 852 and 894 nm. We performed appropriate calculations of the diffuse band emission profiles and compared them with measured profiles. We also performed absorption measurements and compared observed diffuse band profiles with calculated ones. Possible applications of the observed phenomena will be discussed in terms of the solar energy conversion using dense cesium vapor.

  17. The effect of Cs+ ions on codeposition of SiC particles with nickel

    International Nuclear Information System (INIS)

    Research highlights: → The papers describes electrodeposition of SiC particles with nickel matrix in the presence of cesium ions. → Correlations among the Cs+ concentration in the bath, kinetics of the cathodic process, SiC content in the deposits as well as adsorption of Ni2+ ions on SiC were found. → Microhardness of the Ni/SiC deposits was also determined. - Abstract: Electrodeposition of SiC particles (technical powder) with nickel matrix in the presence of cesium ions (0-37.6 mM) was investigated. The influence of Cs+ concentration on cathodic polarization curves was determined in galvanostatic and potentiodynamic measurements. The presence of Cs+ in the solution enhanced in some extent adsorption of Ni2+ ions on SiC, but preferential cesium adsorption occurred simultaneously. The last phenomenon resulted in cesium incorporation in the composite coating. The particle content in the deposits (16-24 vol%) was governed by the amount of nickel ions adsorbed on SiC. Structure of the composite coatings was studied by microscopic observations. At highest Cs+ concentrations, incorporation of small SiC grains was inhibited. Microhardness of deposits (390-800 HV) was directly dependent on the SiC content in the coatings.

  18. [Value of radioactive cesium content in selected food products. I. Content of radioactive cesium in dried milk (1987-1988)].

    Science.gov (United States)

    Skibniewska, K A; Smoczyński, S S; Werner, B

    1993-01-01

    The content of radioactive cesium in dried and dried skimmed milk from selected dairies was double determined. The highest content was found in samples from milk from OSM Siedlce (98 Bq/kg) and skimmed milk from Radzyń Podlaski and Ostrołeka, (the former 90, the latter 62 Bq/kg). The lowest level of radioactive caesium was observed in samples from dried milk from Sieradz, Słupsk, Września, Olecko and Elblag (about or below 10 Bq/kg). Although those levels of contamination with radiocesium didn't exceed values recommended by FAO they were determined as high for year 1987/88 as compared milk data from previous 1985 year. PMID:8016538

  19. Polymer-inorganic coatings containing nanosized sorbents selective to radionuclides. 1. Latex/cobalt hexacyanoferrate(II) composites for cesium fixation.

    Science.gov (United States)

    Bratskaya, Svetlana; Musyanovych, Anna; Zheleznov, Veniamin; Synytska, Alla; Marinin, Dmitry; Simon, Frank; Avramenko, Valentin

    2014-10-01

    Here we present a new approach to improve fixation of radionuclides on contaminated surfaces and eliminate their migration after nuclear accidents. The approach consists in fabrication of latex composite coatings, which combine properties of polymeric dust-suppressors preventing radionuclides migration with aerosols and selective inorganic sorbents blocking radionuclides leaching under contact with ground waters and atmospheric precipitates. Latex/cobalt hexacyanoferrate(II) (CoHCF) composites selective to cesium radionuclides were synthesized via "in situ" growth of CoHCF crystal on the surface of carboxylic or amino latexes using surface functional groups as ion-exchange centers for binding precursor ions Co(2+) and [Fe(CN)6](4-). Casting such composite dispersions with variable content of CoHCF on (137)Cs-contaminated sand has yielded protective coatings, which reduced cesium leaching to 0.4% compared to 70% leaching through original latex coatings. (137)Cs migration from the sand surface was efficiently minimized when the volume fraction of CoHCF in the composite film was as low as 0.46-1.7%. PMID:25203389

  20. Fabrication and performance of fl y ash granule filter for trapping gaseous cesium

    Directory of Open Access Journals (Sweden)

    Park Jang Jin

    2015-09-01

    Full Text Available Although a disk-type fly ash filter has shown a good performance in trapping gaseous cesium, it has difficulty in charging filters into a filter container and discharging waste filters containing radioactive cesium from a container by remote action. To solve the difficulty of the disk-type fly ash filter, five types of granule filters, including a ball type, tube type, and sponge-structure type have been made. Among them, the best filter type was chosen through simple crucible tests. The five types of granule filters packed into containers were loaded into five alumina crucibles of 50 cc. Five grams of CsNO3 was used as a gaseous cesium source. They were then placed in a muffle furnace and heated to 900°C and maintained for 2 hours. After the experiment, the weights of the cesium trapped filters were measured. Among the five types of granule filters, the sponge-structure type granule filter was the best, which has the highest trapping capacity of cesium. Its capacity is 0.42 g-Cs/g-filter. The chosen sponge-structure type granule filters and disk-type filters have been tested using a two-zone tube furnace. Cs volatilization and Cs trapping zones were maintained at 900 and 1000°C, respectively. Sixteen grams of CsNO3 was used as a gaseous cesium source. The cesium trapping profile of the sponge-structure type granule filters was almost similar to that of the disk-type fly ash filters. For both cases, cesium was successfully trapped within the third filter.

  1. Calculations of neutron and proton radii of cesium isotopes. Final report, April 23--September 30, 1993

    International Nuclear Information System (INIS)

    This task involved the calculation of neutron and proton radii of cesium isotopes. The author has written a computer code that calculates radii according to two models: Myers 1983 and FRDM 1992. Results of calculations in both these models for both cesium and francium isotopes are attached as figures. He is currently interpreting these results in collaboration with D. Vieira and J.R. Nix, and they expect to use the computer code for further studies of nuclear radii

  2. Thermoemission and adsorption properties of tungsten alloy with osmium in cesium atoms flow

    International Nuclear Information System (INIS)

    Thermoemission and absorption properties of (110) and (100) planes of monocrystal of W+0.5%Os melt in a flux of cesium atoms are studied. Despite the fact that the electron work function from planes (100) and (110) was only 0.05 eV different it turned out during adsorption of Cs atoms that plane (110) adsorbes cesium atoms much better and reduces the work function to a greater extent

  3. Dosage of cesium 137 in radioactive wastes by the application of sodium tetraphenylborate

    International Nuclear Information System (INIS)

    A simple technique of the dosage of 137Cs has been developed. The technique consists in the formation of cesium tetraphenyl borate, followed by a double extraction with isoamyl acetate, and washing of the organic phase. The counting of known parts of the cesium solution assaying of its purity by γ spectrometry enable the determination of the 137Cs. The yield is about 98 per cent. (authors)

  4. Contribution of the pectin in the cesium elimination in organism. results of analysis on Belarus children

    International Nuclear Information System (INIS)

    The results make appear that the cesium 137 would be eliminated less quick than what the ICRP considered for its models. Pectin would accelerate the cesium elimination but less quick than what is announced by its promotors. Politically speaking, the pectin is ignored by the officials of medicine and radiation protection at the pretext that its efficiency is not proved but no study is made. (N.C.)

  5. Iodine and cesium behavior during the first PBF Severe Fuel Damage Test

    International Nuclear Information System (INIS)

    The results of iodine and cesium measurements made during the Severe Fuel Damage Scoping Test at the Power Burst Facility are presented. On-line gamma spectroscopy and grab samples of the test effluent were used to measure the isotopic release histories at four locations in the effluent sampling system. Total release fractions, release rates, analysis of filter debris, and sample line deposition characteristics are discussed. Iodine and cesium release rate constants measured during the experiment are compared with published NRC data

  6. Iodine and cesium behavior during the first PBF severe fuel damage test

    International Nuclear Information System (INIS)

    The results of iodine and cesium measurements made during the Severe Fuel Damage Scoping Test at the Power Burst Facility are presented. On-line gamma spectroscopy and grab samples of the test effluent were used to measure the isotopic release histories at four locations in the effluent sampling system. Total release fractions, release rates, analysis of filter debris, and sample line deposition characteristics are discussed. Iodine and cesium release rate constants measured during the experiment are compared with published NRC data

  7. Iodine and cesium behavior during the first PBF Severe Fuel Damage test: Chapter 4

    International Nuclear Information System (INIS)

    The results of iodine and cesium measurements made during the Severe Fuel Damage Scoping Test at the Power Burst Facility are presented. On-line gamma spectroscopy and grab samples of the test effluent were used to measure the isotopic release histories at four locations in the effluent sampling system. Total release fractions, release rates, analysis of filter debris, and sample line deposition characteristics are discussed. Iodine and cesium release rate constants measured during the experiment are compared with published NRC data

  8. Enhanced electronic injection in organic light-emitting diodes by incorporating silver nanoclusters and cesium carbonate

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying-Chung; Gao, Chia-Yuan [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung, Taiwan (China); Chen, Kan-Lin [Department of Electronic Engineering, Fortune Institute of Technology, Kaohsiung, Taiwan (China); Sze, Po-Wen [Department of Electro-Optical Science and Engineering, Kao Yuan University, Kaohsiung, Taiwan (China); Huang, Chien-Jung, E-mail: chien@nuk.edu.tw [Department of Applied Physics, National University of Kaohsiung, Kaohsiung, Taiwan (China)

    2015-10-01

    Highlights: • The localized electric field around SNCs is enhanced. • When the cesium carbonate/silver nanoclusters/cesium carbonate electron-injection structure replaces the cesium carbonate electron-injection structure, higher electron-injection ability is obtained. • The structure for efficient electron injection is critical to characteristics of the device. - Abstract: The influence of the cesium carbonate/silver nanoclusters/cesium carbonate electron-injection structure (CSC-EIS) on the performance of organic light-emitting diodes is investigated in this study. The silver nanoclusters (SNCs) are introduced between the electron-injection layers by means of thermal evaporation. When the CSC-EIS replaces the cesium carbonate electron-injection structure, higher electron-injection ability is obtained because the electron-injection barrier between the cathode and the electron-transport layer is remarkably reduced from 1.2 to 0 eV. In addition, surface plasmon resonance effect will cause the enhanced localized electric field around the SNCs, resulting that electron-injection ability is further enhanced from the cathode to the emitting layer.

  9. Measurement of cesium emissions during the vitrification of simulated high level radioactive waste

    International Nuclear Information System (INIS)

    In the Defense Waste Processing Facility at the Savannah River Site, it is desired to eliminate a startup test that would involve adding small amounts of radioactive cesium-137 to simulated high-level waste. In order to eliminate this test, a reliable method for measuring non-radioactive cesium in the offgas system from the glass melter is required. From a pilot scale melter system, offgas particulate samples were taken on filter paper media and analyzed by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The ICPMS method proved to be sufficiently sensitive to measure cesium quantities as low as 0.135 μg, with the sensitivity being limited by the background cesium present in the filter paper. Typical particulate loadings ranged from 800 μg of cesium. This sensitivity allowed determination of cesium decontamination factors for four of the five major components of the offgas system. The decontamination factors measured experimentally compared favorably with the process design basis values

  10. Test evaluation of a cesium vapor source and regulator for thermionic space power systems

    International Nuclear Information System (INIS)

    This paper presents the results of nearly 8000 hours of testing of a fully developed cesium vapor source on the integrated TOPAZ II Ya-21U thermionic space power system. The test period included 4000 hours of system thermal vacuum operation and evaluation by Russian specialists at the Central Design Bureau for Machine Building (CDBMB), St. Petersburg, Russia; nearly 4000 hours of thermal vacuum tests at the Thermionic Systems Evaluation Test (TSET) laboratory; and mechanical tests at the Sandia National Laboratories (SNL), Albuquerque, NM. Testing of the non-nuclear Ya-21U system provided significant information for evaluation and characterization of the cesium vapor source that could not be obtained by development and qualification testing of only components. The Ya-21U system and cesium vapor source were subjected to excessive, unplanned stress levels during the system evaluation tests which resulted in leakage of oxygen into the cesium subsystem and cesium vapor from the TFEs. The information and experience gained during the thermionic system evaluation test are useful for improvement of future cesium vapor subsystem designs, test support equipment, and system test procedures. copyright 1996 American Institute of Physics

  11. Individual difference of concentration of radio cesium on olive flounder (Paralichthys olivaceus)

    International Nuclear Information System (INIS)

    Marine organisms were contaminated with radio cesium released from TEPCO Fukushima Nuclear Power Plants and coastal fisheries are still restricted. Olive flounder is one of the most important fishery species in Japan and live in coastal area. About one hundred of olive flounder were caught in northern and southern part of Fukushima prefecture and the concentrations of radio cesium in muscle of them were measured individually. The averages of concentration (with standard deviations) of total radio cesium in the muscle of the fish were 87.0 (72.3) Bq/kg-wet and 101 (104) Bq/kg-wet in the northern and southern coasts, respectively. Seventy percent of the results were distributed between 50 and 150 Bq/kg-wet but some of them were much higher (and much lower) than the average. According to the individuals with under 200 Bq/kg-wet of radio cesium collected in northern part of Fukushima, the concentrations of radio cesium were correlated to the amounts of 15N in the muscles. It suggests that the concentration of radio cesium in olive flounder might be influenced by the species of prey organisms that individual flounder predated a certain period before catch. (author)

  12. Thermodynamics Features of Cesium and Strontium Extraction by Mixtures of H+CCD- and PEG-400 in FS-13

    Energy Technology Data Exchange (ETDEWEB)

    Nash, K.L. [Washington State University, Chemistry Department, P.O. Box 644630, Pullman, WA 99164-4630 (United States); Zalupski, P. [Washington State University, Chemistry Department, P.O. Box 644630, Pullman, WA 99164-4630 (United States); Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 (United States); Martin, L.R.; Herbst, R.S. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 (United States)

    2009-06-15

    studied using two-phase calorimetry complemented by radiotracer distribution studies. Thermochemical characterization of the partitioning of cesium and strontium from nitric acid solutions into mixtures of the acid form of chlorinated cobalt dicarbollide (H+CCD-) and polyethylene glycol (PEG-400) in FS-13 diluent has been completed employing an isothermal titration microcalorimetry technique used in earlier studies at WSU. The phase transfer reaction for Cs{sup +} is a straight-forward (H{sup +} for Cs{sup +}) cation exchange reaction. In contrast, extraction of Sr{sup 2+} does not proceed without the presence of the co-solvent molecule, PEG-400, which is believed to facilitate the dehydration of the Sr{sup 2+} aquo cation to overcome its resistance to partitioning. The phase transfer reactions for both Cs{sup +} and Sr{sup 2+} are enthalpy driven (exothermic), but compensated to different degrees by unfavorable phase-transfer entropy. The results of the calorimetry studies suggest that the PEG-400 functions as a stoichiometric reagent rather than acting simply as a phase transfer catalyst or phase modifier. The calorimetry results also demonstrate that the extraction of Sr{sup 2+} is complex, including evidence for both the partitioning of Sr(NO{sub 3}){sup +} and endothermic ion pairing interactions in the organic phase that contribute to the net enthalpic effect. The thermodynamics of the liquid-liquid distribution equilibria are discussed mainly considering basic features of ion solvation thermochemistry. Work at Washington State University was supported under subcontract number 11W-2452-0742 with the Idaho National Laboratory, Laboratory Director's Research and Development program. (authors)

  13. Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin

    International Nuclear Information System (INIS)

    The 177 underground storage tanks at the DOE's Hanford Site contain an estimated 180 million tons of high-level radioactive wastes. It is desirable to remove and concentrate the highly radioactive fraction of the tank wastes for vitrification. Resorcinol-formaldehyde (R-F) resin, an organic ion-exchange resin with high selectivity and capacity for the cesium ion, which is a candidate ion-exchange material for use in remediation of tank wastes. The report includes information on the structure/function analysis of R-F resin and the synthetic factors that affect performance of the resin. CS-100, a commercially available phenol-formaldehyde (P-F) resin, and currently the baseline ion-exchanger for removal of cesium ion at Hanford, is compared with the R-F resin. The primary structural unit of the R-F resin was determined to consist of a 1,2,3,4-tetrasubstituted resorcinol ring unit while CS-100, was composed mainly of a 1,2,4-trisubstituted ring. CS-100 shows the presence of phenoxy-ether groups, and this may account for the much lower decontamination factor of CS-100 for cesium ion. Curing temperatures for the R-F resin were found to be optimal at 105--130C. At lower temperatures, insufficient curing, hence crosslinking, of the polymer resin occurs and selectivity for cesium drops. Curing at elevated temperatures leads to chemical degradation. Optimal particle size for R-F resin is in the range of 20--50 mesh-sized particles. R-F resin undergoes chemical degradation or oxidation which destroys ion-exchange sites. The ion-exchange sites (hydroxyl groups) are converted to quinones and ketones. CS-100, though it has much lower performance for cesium ion-exchange, is significantly more chemically stable than R-F resin. To gamma radiation, CS-100 is more radiolytically stable than R-F resin

  14. Engineered Materials for Cesium and Strontium Storage Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Sean M. McDeavitt

    2010-04-14

    Closing the nuclear fuel cycle requires reprocessing spent fuel to recover the long-lived components that still have useful energy content while immobilizing the remnant waste fission products in stable forms. At the genesis of this project, next generation spent fuel reprocessing methods were being developed as part of the U.S. Department of Energy's Advanced Fuel Cycle Initiative. One of these processes was focused on solvent extraction schemes to isolate cesium (Cs) and strontium (Sr) from spent nuclear fuel. Isolating these isotopes for short-term decay storage eases the design requirements for long-term repository disposal; a significant amount of the radiation and decay heat in fission product waste comes from Cs-137 and Sr-90. For the purposes of this project, the Fission Product Extraction (FPEX) process is being considered to be the baseline extraction method. The objective of this project was to evaluate the nature and behavior of candidate materials for cesium and strontium immobilization; this will include assessments with minor additions of yttrium, barium, and rubidium in these materials. More specifically, the proposed research achieved the following objectives (as stated in the original proposal): (1) Synthesize simulated storage ceramics for Cs and Sr using an existing labscale steam reformer at Purdue University. The simulated storage materials will include aluminosilicates, zirconates and other stable ceramics with the potential for high Cs and Sr loading. (2) Characterize the immobilization performance, phase structure, thermal properties and stability of the simulated storage ceramics. The ceramic products will be stable oxide powders and will be characterized to quantify their leach resistance, phase structure, and thermophysical properties. The research progressed in two stages. First, a steam reforming process was used to generate candidate Cs/Sr storage materials for characterization. This portion of the research was carried out at

  15. Engineered Materials for Cesium and Strontium Storage. Final Technical Report

    International Nuclear Information System (INIS)

    Closing the nuclear fuel cycle requires reprocessing spent fuel to recover the long-lived components that still have useful energy content while immobilizing the remnant waste fission products in stable forms. At the genesis of this project, next generation spent fuel reprocessing methods were being developed as part of the U.S. Department of Energy's Advanced Fuel Cycle Initiative. One of these processes was focused on solvent extraction schemes to isolate cesium (Cs) and strontium (Sr) from spent nuclear fuel. Isolating these isotopes for short-term decay storage eases the design requirements for long-term repository disposal; a significant amount of the radiation and decay heat in fission product waste comes from Cs-137 and Sr-90. For the purposes of this project, the Fission Product Extraction (FPEX) process is being considered to be the baseline extraction method. The objective of this project was to evaluate the nature and behavior of candidate materials for cesium and strontium immobilization; this will include assessments with minor additions of yttrium, barium, and rubidium in these materials. More specifically, the proposed research achieved the following objectives (as stated in the original proposal): (1) Synthesize simulated storage ceramics for Cs and Sr using an existing labscale steam reformer at Purdue University. The simulated storage materials will include aluminosilicates, zirconates and other stable ceramics with the potential for high Cs and Sr loading. (2) Characterize the immobilization performance, phase structure, thermal properties and stability of the simulated storage ceramics. The ceramic products will be stable oxide powders and will be characterized to quantify their leach resistance, phase structure, and thermophysical properties. The research progressed in two stages. First, a steam reforming process was used to generate candidate Cs/Sr storage materials for characterization. This portion of the research was carried out at Purdue

  16. Work function measurements during plasma exposition at conditions relevant in negative ion sources for the ITER neutral beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Gutser, R. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany); Wimmer, C. [Lst. f. Experimentelle Plasmaphysik, Universitaet Augsburg, 86135 Augsburg (Germany); Fantz, U. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany); Lst. f. Experimentelle Plasmaphysik, Universitaet Augsburg, 86135 Augsburg (Germany)

    2011-02-15

    Cesium seeded sources for surface generated negative hydrogen ions are major components of neutral beam injection systems in future large-scale fusion experiments such as ITER. The stability and delivered current density depend highly on the work function during vacuum and plasma phases of the ion source. One of the most important quantities that affect the source performance is the work function. A modified photocurrent method was developed to measure the temporal behavior of the work function during and after cesium evaporation. The investigation of cesium exposed Mo and MoLa samples under ITER negative hydrogen ion based neutral beam injection relevant surface and plasma conditions showed the influence of impurities which result in a fast degradation when the plasma exposure or the cesium flux onto the sample is stopped. A minimum work function close to that of bulk cesium was obtained under the influence of the plasma exposition, while a significantly higher work function was observed under ITER-like vacuum conditions.

  17. Optimization conditions for the separation of rare earth elements, americium, curium and cesium with HPLC technique

    International Nuclear Information System (INIS)

    In order to validate the neutronic code calculations used in the nuclear field, it is necessary to quantify the isotopic composition of the nuclear irradiated fuels with high precision and accuracy. A separation step whose objective is to isolate the elements of interest in a fraction as pure as possible, is performed before mass spectrometry detection (MC-ICP-MS, TIMS), in order to eliminate isobaric interferences. In a first step, uranium and plutonium are separated from the fission products by ion exchange chromatography. Then, fission products are separated by high performance liquid chromatography (HPLC). A gradient separation with a silica sulphonated support as stationary phase and hydroxy-methyl butyric acid (HMB) as eluent solution provides a good degree of separation of the rare earth elements, Am, Cm and Cs. But, for a same manufacturer, the rate of sulphonated groups is variable from one column to another for a given production batch. For every replacement of column, it is necessary to adjust the separation conditions. Furthermore, the high radioactivity of the samples injected damages the stationary phase, dragging a regular renewal of the columns. The goal of this study is to determine the optimal separation conditions with a minimum of tests in order to limit the time assigned to this operation. A first Doehlert experimental design with pH and HMB concentration as variables has been implemented to optimize Gd, Eu separation, in isocratic initial conditions. A second one has been tested in order to separate the higher lanthanides and to fix the final conditions of the gradient separation. A last set of tests has been performed to characterize the cesium behaviour. Finally, the gradient conditions have been adjusted in order to perform the full separation of lanthanides, Cs, Am and Cm with nuclear facilities. (author)

  18. Decontamination of cesium, strontium, and cobalt from aqueous solutions by bentonite

    Energy Technology Data Exchange (ETDEWEB)

    Khan, M.A. [Univ. of the Punjab, Lahore (Pakistan); Khan, S.A. [Government F.C. College, Lahore (Pakistan)

    1996-12-31

    Sorption studies of cesium, strontium, and cobalt (Cs, Sr, and Co) on bentonite under various experimental conditions, such as contact time, pH, sorbent and sorbate concentration, and temperature, have been performed. The sorption data for all these metals have been interpreted in terms of Freundlich, Langmuir, and Dubinin-Radushkevich equations. Thermodynamics parameters, such as heat of sorption {Delta}H{degrees}, free energy change {Delta}G{degrees}, and entropy change {Delta}S{degrees}, for the sorption of these metals on bentonite have been calculated. The value of {Delta}H{degrees} shows that the sorption of Cs was exothermic, while the sorption of Sr and Co on bentonite were endothermic in nature. The value of {Delta}G{degrees} for their sorption was negative, showing the spontaneity of the process. The maximum loading capacity of Cs, Sr, and Co were 75.5, 22, and 27.5 meq, respectively, for 100 g of bentonite. The mean free energy E of Cs, Sr, and Co sorption on bentonite was 14.5, 9, and 7.7 kJ/mol, respectively. The value of E indicates that ion exchange may be the predominant mode of sorption for these radionuclides. The desorption studies with 0.01 M CaCl{sub 2} and groundwater at low-metal loading on bentonite showed that about 95% of Cs, 85-90% of Sr, and 97% of Co were irreversibly sorbed. Bentonite could be effectively used for the decontamination of wastewater effluent containing low concentrations of radioactive nuclides of Cs, Sr, and Co. 16 refs., 7 figs., 3 tabs.

  19. A cesium copper vanadyl-diphosphate: Synthesis, crystal structure and physical properties

    Energy Technology Data Exchange (ETDEWEB)

    Shvanskaya, Larisa, E-mail: lshvanskaya@mail.ru [Geology Faculty, M.V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation); National University of Science and Technology “MISiS”, Moscow 119049 (Russian Federation); Yakubovich, Olga; Bychkov, Andrey; Shcherbakov, Vasiliy [Geology Faculty, M.V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Golovanov, Alexey; Zvereva, Elena [Physics Faculty, M.V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Volkova, Olga [Physics Faculty, M.V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Theoretical Physics and Applied Mathematics Department, Ural Federal University, 620002 Ekaterinburg (Russian Federation); Vasiliev, Alexander [Physics Faculty, M.V. Lomonosov Moscow State University, Moscow 119991 (Russian Federation); National University of Science and Technology “MISiS”, Moscow 119049 (Russian Federation); Theoretical Physics and Applied Mathematics Department, Ural Federal University, 620002 Ekaterinburg (Russian Federation)

    2015-02-15

    A non-centrosymmetric orthorhombic diphosphate, Cs{sub 2}Cu{sub 1+x}(VO){sub 2−x}(P{sub 2}O{sub 7}){sub 2} (x=0.1) with a=13.7364(2) Å, b=9.2666(2) Å, c=11.5678(2) Å, Z=4, has been isolated. Its 3D framework is built from Cu atoms in square pyramidal and square planar coordination, VO{sub 5} tetragonal pyramids and P{sub 2}O{sub 7} diphosphate groups, sharing vertices. Large channels are fulfilled by cesium atoms. The ESR study reveals a similarity in behaviour of two paramagnetic (Cu and V) subsystems. The temperature dependences of the ESR linewidth and static magnetic susceptibility data present evidences for a cluster type magnetic ordering in the title compound at T⁎=22 K. The weakness of the relevant anomalies reflects presumably obvious Cu{sup 2+} ions and (VO){sup 2+} units disorder in the system. It is supposed that the charge and geometry of the framework are controlled by the Cu{sup 2+}/(VO){sup 2+} ratio; its variation may lead to a design of new materials. - Graphical abstract: A microporous 3D anionic framework of the first copper vanadium-diphosphate Cs{sub 2}Cu{sub 1.1}(VO){sub 1.9}(P{sub 2}O{sub 7}){sub 2}. The similarity in behaviour of Cu and V paramagnetic subsystems revealed by ESR study. - Highlights: • The first copper vanadium-diphosphate Cs{sub 2}Cu{sub 1.1}(VO){sub 1.9}(P{sub 2}O{sub 7}){sub 2} is reported. • A 3D anionic framework is characterized by disorder in distribution of Cu and V atoms. • Structural relations with topologically similar compounds are discussed. • The similarity in behaviour of Cu and V paramagnetic subsystems has been revealed.

  20. Silicon Control of Strontium and Cesium Partitioning in Hydroxide-Weathered Sediments

    International Nuclear Information System (INIS)

    Cation partitioning in an aqueous soil suspension depends on the coupling of reaction time, sorbate amount and mineral weathering reactions. These factors were varied in sediment suspension experiments to identify geochemical processes that affect migration of Sr2+ and Cs+ introduced to the subsurface by caustic high level radioactive waste (HLRW). Three glacio-fluvial and lacustrine sediments from the Hanford Site were subjected to hyperalkaline (pH > 13), Na-Al-NO3-OH solution conditions within a gradient field of (i) sorptive concentration (10-5 - 10-3 M) and (ii) reaction time (0-365 d). Strontium uptake (qSr) exceeded that of cesium at nearly all reaction times. Sorbent affinity for both Cs+ and Sr2+ increased with clay plus silt content at early times, but a prolonged slow uptake process was observed over the course of sediment weathering that erased the texture effect for Sr2+; all sediments showed similar mass normalized uptake after several months of reaction time. Strontium became progressively recalcitrant to desorption after 92 d, with accumulation and aging of neoformed aluminosilicates. Formation of Cs+ and Sr2+-containing cancrinite and sodalite was observed after 183 d by SEM and synchrotron u-XRF and u-XRD. EXAFS data showed incorporation of Sr2+ into both feldspathoid and SrCO3(s) coordination environments after one year. Adsorption was predominant at early times and low sorbate amount, whereas recipitation, controlled largely by sediment Si release, became increasingly important at longer times and higher sorbate amount. Kinetics of contaminant desorption at pH 8 from one year-weathered sediments showed significant dependence on background cation (Ca2+ versus K+) composition. Results of this study indicate that co-precipitation and ion exchange in neoformed aluminosilicates may be an important mechanism controlling Sr2+ and Cs+ mobility in siliceous sediments impacted by hyperalkaline HLRW