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Sample records for cs ion exchange

  1. Evaluation of ferrocyanide anion exchange resins regarding the uptake of Cs+ ions and their regeneration

    International Nuclear Information System (INIS)

    Won, Hui Jun; Mooon, Jei Kwon; Jung, Chong Hun; Chung, Won Yang

    2008-01-01

    Ferrocyanide-anion exchange resin was prepared and the prepared ion exchange resins were tested on the ability to uptake Cs + ion. The prepared ion exchange resins were resin-KCoFC, resin-KNiFC, and resin-KCuFC. The three tested ion exchange resins showed ion exchange selectivity on the Cs + ion of the surrogate soil decontamination solution, and resin- KCoFC showed the best Cs + ion uptake capability among the tested ion exchange resins. The ion exchange behaviors were explained well by the modified Dubinin-Polanyi equation. A regeneration feasibility study of the spent ion exchange resins was also performed by the successive application of hydrogen peroxide and hydrazine. The desorption of the Cs + ion from the ion exchange resin satisfied the electroneutrality condition in the oxidation step; the desorption of the Fe 2+ ion in the reduction step could also be reduced by adding the K + ion

  2. Treatment of Soil Decontamination Solution by the Cs{sup +} Ion Selective Ion Exchange Resin

    Energy Technology Data Exchange (ETDEWEB)

    Won, Hui Jun; Kim, Gye Nam; Jung, Chung Hun; Oh, Won Zin [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    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{sup +} 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.

  3. The selective separation of Cs and Sr ion on the inorganic ion-exchanger zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hun Hwee; Min, Byeog Heon [Hoseo University, Taegu (Korea)

    1998-04-01

    This study shows the selective separation of Cs and Sr ion on the inorganic ion-exchanger zeolites such as clinoptilolite, Y-type CBV760, CBV780 and A-type 3A. The selective separation of Cs and Sr on these zeolites was examined using batch and continuous column experiments. For the selective separation of Cs and Sr from a synthetic wastewater, adsorption rate of Cs increased in the order, clinoptilolite> 3A>> CBV760> CBV780, adsorption rate of Sr increased in the other, 3A>> clinoptilolite> CBV760> CBV780. For the clinoptilolite, the adsorption rate of Cs reached about 96 {approx} 98% within 3h. The adsorption rate of Sr on 3A reached about 99% within 3h. (author). 40 refs., 27 figs., 4 tabs.

  4. Solidification of 137Cs into potassium cobalt hexacyanoferrate (II) ion exchanger

    International Nuclear Information System (INIS)

    Lehto, J.; Harjula, R.; Haukka, S.; Wallace, J.

    1989-01-01

    An inorganic ion exchange, potassium cobalt hexacyanoferrate(II), has been studied for the separation of 137 Cs from nuclear waste solutions. This exchanges is highly selective for cesium over other alkali metal ions and can be synthesized in granular form suitable for column operations. Pilot-plant experiments were carried out at a NPP to test the exchanges for solidification of 137 Cs from an evaporator concentrate. The results were encouraging: decontamination factors and volume reduction factors were both very high. A full-scale separation plant is now under construction plans call for the exchanges, loaded with 137 Cs, to be disposed of in stainless steel columns, sealed by welding and enclosed in concrete block. According to the authors this multibarrier procedure provides a safe final disposal solution

  5. Preparation of the Hexacyanoferrate Ion Exchanger Matrix to Concentrate 137Cs from Sea Water

    International Nuclear Information System (INIS)

    Murdahayu Makmur

    2007-01-01

    Preparation of the hexacyanoferrate ion exchanger matrix to concentrate 137 Cs from large volume sea water has been done. The Pre-concentration is needed because 137 Cs concentration in sea water is too low. The hexacyanoferrate ion exchanger matrix can be prepared by performing the reaction of 10 gram silica gel with potassium hexacyanoferrate on concentration variation of 0.0025 M - 0.04 M and copper chloride on concentration variation of 0.005 M - 0.08 M. The volume of each reagent was 25 ml. The performance of the ion exchanger matrix depends on the chemical compositions both of the mixtures, it was expected that no remaining Fe ion and free Cu from the initial reagent. The final effluent will analyzed for Fe and Cu using Atomic Absorption Spectrometer. The optimal molar composition ration for potassium hexacyanoferrate and copper chloride was 0.5 for 10 gram silica gel. (author)

  6. Evaluation of ferrocyanide anion exchange resins regarding the uptake of Cs{sup +} ions and their regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Won, Hui Jun; Mooon, Jei Kwon; Jung, Chong Hun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Chung, Won Yang [Kangwon University, Chuncheon (Korea, Republic of)

    2008-10-15

    Ferrocyanide-anion exchange resin was prepared and the prepared ion exchange resins were tested on the ability to uptake Cs{sup +} ion. The prepared ion exchange resins were resin-KCoFC, resin-KNiFC, and resin-KCuFC. The three tested ion exchange resins showed ion exchange selectivity on the Cs{sup +} ion of the surrogate soil decontamination solution, and resin- KCoFC showed the best Cs{sup +} ion uptake capability among the tested ion exchange resins. The ion exchange behaviors were explained well by the modified Dubinin-Polanyi equation. A regeneration feasibility study of the spent ion exchange resins was also performed by the successive application of hydrogen peroxide and hydrazine. The desorption of the Cs{sup +} ion from the ion exchange resin satisfied the electroneutrality condition in the oxidation step; the desorption of the Fe{sup 2+} ion in the reduction step could also be reduced by adding the K{sup +} ion.

  7. Sr2+ and Cs+ ion exchange properties of KLn(PO3)4: Ln = Ce and Eu

    International Nuclear Information System (INIS)

    Samatha, B.; Achary, S.N.; Tyagi, A.K.; Ramkumar, Jayshree; Chandramouleeswaran, S.

    2014-01-01

    With the aim to study the potential of layered phosphates as ion exchangers two stoichiometric compositions as KLn(PO 3 ) 4 with Ln = Ce and Eu were prepared by solid state reaction and characterized by powder X-ray diffraction method. The Cs + and Sr 2+ exchange properties of both materials were investigated using standard solutions of Sr 2 + or Cs + in low acidic aqueous medium

  8. Retention of 60Co, 85Sr and 137Cs on inorganic ion exchangers

    International Nuclear Information System (INIS)

    Dozol, J.F.; Eymard, S.

    1983-11-01

    The aim of the study is the treatment of radioactive wastes produced in plutonium fuel fabrication or in spent fuel reprocessing by inorganic ion exchangers for ultimate storage. This rapport, gives the distribution coefficients of 60 Co, 85 Sr, 137 Cs (in sodium nitrate medium at different concentration of sodium: .23g/l, 1 g/l, 10 g/l) obtained with different inorganic exchangers: titanium oxyde, sodium titanate, sodium zirconate, sodium niobate, sodium tantalate, titanium phosphate, zirconium phosphate, ammonium phosphotungstate in zirconium phosphate, polyantimonic acid amorphous aluminosilicate and several zeolites (ZBS 15 from OXYMIN, ZEOLON 400, ZEOLON 500, ZEOLON 900 from Norton, IE 96, A 51, 13 X from Union Carbide) [fr

  9. Leaching of 60 Co and 137 Cs from spent ion exchange resins in ...

    Indian Academy of Sciences (India)

    Cement; radioactive waste; composite; waste management. Abstract. The leaching rate of 60Co and 137Cs from the spent cation exchange resins in cement–bentonite matrix has been studied. The solidification matrix was a standard Portland cement mixed with 290–350 (kg/m3) spent cation exchange resins, with or ...

  10. Separation and immobilization of Sr and Cs contained in acidic media by using inorganic ion-exchangers. Literature survey

    Energy Technology Data Exchange (ETDEWEB)

    Yamagishi, Isao [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-07-01

    The present study deals with the survey of inorganic ion-exchangers suitable for separation and immobilization of Sr and Cs contained in acidic high-level liquid waste. The stabilities of published waste forms and their preparation processes were evaluated from the standpoint of conversion of exchangers containing Sr and Cs into appropriate waste forms. The essential results are below. (1) For separation and immobilization of Cs, crystalline silicotitanate seems to be the most promising exchanger. Insoluble ferrocyanides and phosphates are not suitable for immobilization without additives. Mordenite is inexpensive and commercially available but it would dissolve in highly acidic media. (2) For selective separation of Sr, there is no promising exchanger up to now. It is necessary either to modify separation condition or to synthesize a novel exchanger. (3) Soluble salts, glasses and ceramics are proposed as a storage or disposal form of separated Sr and Cs. Ceramics sintered by hot-pressing are favorable waste forms of inorganic ion-exchangers but their leachabilities and thermal conductivities are largely influenced by qualities of products. Crystallinity of a sintered exchanger depends on its composition. Exchanges of low Cs contents are often converted into amorphous materials whose chemical stabilities depend on solubilities of components of exchangers. (4) A new exchanger to be synthesized is crystalline and selective toward Sr and Cs. One meq/g is enough for Sr and Cs capacities, which are restricted by thermal and transmutation effects. Composition of the exchanger should be selected from the point of a scenario of separation and disposal. The solubilities of SiO{sub 2}, TiO{sub 2}, ZrO{sub 2}, Nb{sub 2}O{sub 5} and Ta{sub 2}O{sub 5} are low in acidic media and those of Al{sub 2}O{sub 3}, TiO{sub 2} and ZrO{sub 2}, in disposal circumstances. (5) Future works are optimization of separation scheme including development of exchangers, simplification of

  11. Hydrothermal preparation of zeolite Li-A and ion exchange properties of Cs and Sr in salt waste

    International Nuclear Information System (INIS)

    Lee, S. H.; Kim, J. G.; Lee, J. H.; Kim, J. H.

    2005-01-01

    An advanced spent fuel management process that were based on Li reduction of the oxide spent fuel to a metallic form will generate a LiCl waste. Zeolite A has been reported as a promising immobilization medium for waste salt with CsCl and SrCl 2 . However, Sodium is accumulated as an ionic form (Na + -ion) in molten salt during ion exchange step between Na + -ion in zeolite A and Li + -ion in the molten salt. Therefore, zeolite Na-A need to be replaced by the Li-type zeolite for recycling the salt waste by removing the Cs and Sr ions. In this study, the hydrothermal preparation of zeolite Li-A was performed in 350ml pressure vessel by P. Norby method. The preparation characteristics of zeolite Li-A was investigated. And the ion exchange properties of Cs and Sr in molten LiCl salt were investigated under the condition of 923K using zeolite 4A and prepared zeolite Li-A

  12. Adsorption Isotherms of Cs+, Co2+, Zn2+ and Eu3+ on Zirconium Vanadate Ion-Exchanger

    International Nuclear Information System (INIS)

    Shady, S.A.; El-Ashery, S.M.; El-Naggar, I.M.

    2009-01-01

    Zirconium vanadate had been prepared by the dropwise addition of 0.1 M sodium vanadate and 0.1 M zirconyl chloride by molar ratio of zirconium/vanadium 2. Exchange isotherms for Cs + /H + , Co 2+ /H + ,Zn 2+ /H + and Eu 3+ /H + have been determined at 25, 40 and 60 degree C. Besides, it was proved that cesium, cobalt, zinc and europium are chemically adsorbed. Moreover, the heat of adsorption of these ions on zirconium vanadate had been calculated and indicated that zirconium vanadate is of endothermic behavior towards these ions

  13. Radiation deterioration of ion-exchange Nafion N117CS membranes

    International Nuclear Information System (INIS)

    Iwai, Yasunori; Hiroki, Akihiro; Tamada, Masao; Isobe, Kanetsugu; Yamanishi, Toshihiko

    2010-01-01

    The cation-exchange Nafion N117 membranes swelling in electrolyte solution were irradiated with γ-rays or electron beams at various doses up to 1500 kGy in the temperature range from room temperature to 343 K to obtain detailed information on the effect of ion-exchange on the radiation deterioration in mechanical properties and ion-exchange capacity. Considerable deterioration in mechanical properties was observed when the Nafion membranes swelling in electrolyte solution were irradiated. A reason is the promotion of degradation with oxygen molecules produced by the irradiation of electrolyte solution. The concentration of electrolyte solution influenced strongly the radiation deterioration in mechanical properties. Keeping the concentration of metal ions to be negligible is important when electrolyzed highly radioactive solution in the light of the durability of polyperfluorosulfonic acid (PFSA) membrane. A sort of cation in electrolyte solution negligibly influenced radiation deterioration in mechanical properties. A sort of anion in electrolyte solution had negligible effect on radiation deterioration in mechanical properties and ion-exchange capacity. The discrepancy in the radiation deterioration in mechanical properties of Nafion membranes swelling in NaCl solution was observed between the specimens irradiated with γ-rays and electron beams. This discrepancy can be explained from the low diffusivity of oxygen from bulk into the membrane.

  14. Curing time effect on the fraction of 137Cs from cement- ion exchange resins-bentonite clay composition

    International Nuclear Information System (INIS)

    Plecas, I.; Dimovic, S.

    2007-01-01

    Curing conditions and time are critically important in leach studies since the extent of hydratation of the cement materials determines how much hydratation product develops and whether it is available to block the pore network, thereby reducing leaching.[1,2]. To assess the safety of disposal of radioactive waste material in cement, curing conditions and time of leaching radionuclide 137 Cs has been studied in this paper. Leaching tests in cement-ion exchange resins-bentonite matrix, were carried out in accordance with a method recommended by IAEA. Curing conditions and curing time prior to commencing the leaching test are critically important in leach studies since the extent of hydration of the cement materials determines how much hydration product develop and whether it is available to block the pore network, thereby reducing leaching. Incremental leaching rates R n (cm/d) of 137 Cs from cement-ion exchange resins-bentonite matrix after 180 days were measured. The results presented in this paper are examples of results obtained in a 20-year concrete testing project which will influence the design of the engineer trenches system for future central Serbian radioactive waste storing center. (author)

  15. Preparation of SiO2-KCoFC composite ion-exchanger for removal of Cs in the soil decontamination waste solution

    International Nuclear Information System (INIS)

    Lee, Jung Joon; Moon, Jei kwon; Lee, Kune Woo

    2009-01-01

    The soil decontamination process has been developed for remediate the soil wastes excavated from the TRIGA research reactor sites. Even though the process was proven to be very effective for decontaminate the radioactive nuclides such as cesium and cobalt, the secondary spent solution should be treated with an appropriate method to minimize the waste volume. There are mainly two components in the spent decontamination solution of Cs and Co. The Co in the waste solution can be removed easily by precipitation under a basic condition. However, since the Cs is hardly removed by precipitation, an appropriate selective removal method should be employed. In this study, an inorganic composite ion exchanger of SiO 2 -KCoFC was prepared by sol-gel method for a removal of Cs in the decontamination waste solution. An optimum condition for a preparation of the composite ion exchanger and the adsorption performances of the prepared composite ion exchangers were evaluated

  16. Leaching of Co and Cs from spent ion exchange resins in cement ...

    Indian Academy of Sciences (India)

    Unknown

    2003-08-22

    Aug 22, 2003 ... active waste management for a future Serbian radioactive waste disposal centre. Keywords. Cement ... cost, easy operation and radiation and thermal stability. It is generally .... Initial activity, A0 = 8,0⋅107 Bq/per sample (60Co and 137Cs). Table 2. ... Hespe E D 1971 Atomic Energy Rev. 9 195. Plecas I ...

  17. Small Column Ion Exchange

    International Nuclear Information System (INIS)

    Huff, Thomas

    2010-01-01

    Small Column Ion Exchange (SCIX) leverages a suite of technologies developed by DOE across the complex to achieve lifecycle savings. Technologies are applicable to multiple sites. Early testing supported multiple sites. Balance of SRS SCIX testing supports SRS deployment. A forma Systems Engineering Evaluation (SEE) was performed and selected Small Column Ion Exchange columns containing Crystalline Silicotitanate (CST) in a 2-column lead/lag configuration. SEE considered use of Spherical Resorcinol-Formaldehyde (sRF). Advantages of approach at SRS include: (1) no new buildings, (2) low volume of Cs waste in solid form compared to aqueous strip effluent; and availability of downstream processing facilities for immediate processing of spent resin.

  18. Ion exchange technology assessment report

    International Nuclear Information System (INIS)

    Duhn, E.F.

    1992-01-01

    In the execution of its charter, the SRS Ion Exchange Technology Assessment Team has determined that ion exchange (IX) technology has evolved to the point where it should now be considered as a viable alternative to the SRS reference ITP/LW/PH process. The ion exchange media available today offer the ability to design ion exchange processing systems tailored to the unique physical and chemical properties of SRS soluble HLW's. The technical assessment of IX technology and its applicability to the processing of SRS soluble HLW has demonstrated that IX is unquestionably a viable technology. A task team was chartered to evaluate the technology of ion exchange and its potential for replacing the present In-Tank Precipitation and proposed Late Wash processes to remove Cs, Sr, and Pu from soluble salt solutions at the Savannah River Site. This report documents the ion exchange technology assessment and conclusions of the task team

  19. Ion exchange equilibrium constants

    CERN Document Server

    Marcus, Y

    2013-01-01

    Ion Exchange Equilibrium Constants focuses on the test-compilation of equilibrium constants for ion exchange reactions. The book first underscores the scope of the compilation, equilibrium constants, symbols used, and arrangement of the table. The manuscript then presents the table of equilibrium constants, including polystyrene sulfonate cation exchanger, polyacrylate cation exchanger, polymethacrylate cation exchanger, polysterene phosphate cation exchanger, and zirconium phosphate cation exchanger. The text highlights zirconium oxide anion exchanger, zeolite type 13Y cation exchanger, and

  20. 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.

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

    International Nuclear Information System (INIS)

    Brown, G.N.; Adami, S.R.; Bray, L.A.

    1995-09-01

    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. Chemical and radiation stability of SuperLig{reg_sign}644, resorcinol-formaldehyde, and CS-100 cesium ion exchange materials

    Energy Technology Data Exchange (ETDEWEB)

    Brown, G.N.; Adami, S.R.; Bray, L.A. [and others

    1995-09-01

    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.

  3. Organic decontamination by ion exchange

    International Nuclear Information System (INIS)

    Wilson, T.R.

    1994-01-01

    This study has successfully identified ion exchanger media suitable for decontaminating the 5500-gallon organic layer in Tank 241-C-103. Decontamination of radionuclides is necessary to meet shipping, incinerator site storage, and incineration feed requirements. The exchanger media were identified through a literature search and experiments at the Russian Institute for Physical Chemistry. The principal radionuclides addressed are Cs-137 and Sr-90. Recommendations for an experimental program plan conclude the discussion. The experimental program would provide the data necessary for plant design specifications for a column and for ion exchange media to be used in decontaminating the organic layer

  4. Sorption study and contribution of ion exchange in the dynamics of 137Cs n highly weathered soils

    International Nuclear Information System (INIS)

    Nascimento Sobrinho, Guilherme Augusto

    2014-01-01

    The present study investigated the sorption kinetics and the reversibility of 137 Cs within highly weathered soils, by means of sorption isotherms and desorption with three concentrations of silver thiourea (AgTU). For this purpose, four soils were selected based on their mineralogy and pedogenetics and sampled from lysimeters placed within the experimental area of the Tropical Radioecology Laboratory of the Institute for Radioprotection and Dosimetry. Three of them were tropical soils, belonging to the Argissolo (ARG), Latossolo vermelho (LV) and Latossolo vermelho amarelo (LVA) classes, and one subtropical, belonging to the Nitossolo (NIT) class. The 'goodness-of-fit' of the constant partition, Langmuir and Freundlich isotherms to the experimental data were assessed by means of a 'traditional' approach, i.e. correlation (R) and determination (R 2 ) coefficients, and a 'theoretic-informative' one, based upon the Corrected Akaike Information Criteria (AICc). In this work became clear that even presenting high affinity for the soil surface, once the sorption equilibrium was reached within 24 h (66 to 97% of sorbed 137 Cs), quite a lot of this radionuclide remains easily mobile (40 to 73% of desorbed 137 Cs), by means of a single extraction with AgTU 0,05 mol.L-1, and that such reversibility relates in an inverse manner to the sorption capacity of the studied soils for 137 Cs. This work pointed also that the constant partition model, mostly known as Kdi, does not fit at all for the sorption data gathered for four highly weathered soils from four mineralogical groups, and for a very dilute solution of 137 Cs. The mathematical model that most adequately described the sorption data for the four studied soils was the Langmuir equation (R 2 > 0,95). The multi model analysis was not able to support generalizations for the four soils. The three models considered in this study provided good predictions of the sorbed 137 Cs for the ARG, LVA and NIT samples (ΔAICc AICc = 0

  5. Highly Emissive Divalent-Ion-Doped Colloidal CsPb1–xMxBr3 Perovskite Nanocrystals through Cation Exchange

    Science.gov (United States)

    2017-01-01

    Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition tuning through topotactic anion exchange. In contrast, property control by cation exchange is still underdeveloped for colloidal CsPbX3 NCs. Here, we present a method that allows partial cation exchange in colloidal CsPbBr3 NCs, whereby Pb2+ is exchanged for several isovalent cations, resulting in doped CsPb1–xMxBr3 NCs (M= Sn2+, Cd2+, and Zn2+; 0 50%), sharp absorption features, and narrow emission of the parent CsPbBr3 NCs. The blue-shift in the optical spectra is attributed to the lattice contraction that accompanies the Pb2+ for M2+ cation exchange and is observed to scale linearly with the lattice contraction. This work opens up new possibilities to engineer the properties of halide perovskite NCs, which to date are demonstrated to be the only known system where cation and anion exchange reactions can be sequentially combined while preserving the original NC shape, resulting in compositionally diverse perovskite NCs. PMID:28260380

  6. Fundamentals of ion exchange

    International Nuclear Information System (INIS)

    Townsend, R.P.

    1993-01-01

    In this paper the fundamentals of ion exchange mechanisms and their thermodynamics are described. A range of ion exchange materials is considered and problems of communication and technology transfer between scientists working in the field are discussed. (UK)

  7. Inorganic ion exchange evaluation and design: Silicotitanate ion exchange waste conversion

    International Nuclear Information System (INIS)

    Balmer, M.L.; Bunker, B.C.

    1995-03-01

    Ion exchange materials are being evaluated for removing Cs, SR from tank waste. Thermal conversion of a variety of compositions within the Cs 2 O-TiO 2 -SiO 2 phase diagram yielded both glass and crystalline materials, some of which show low leach rates and negligible Cs losses during heat treatment. A new material, CsTiSi 2 0 6 , with a structure isomorphous to pollucite (CsAlSi 2 0 6 ) has been identified. This material represents a new class of crystalline zeolite materials which contain large amounts of titanium. Direct conversion of Cs loaded silicotitanate ion exchangers to CsTiSi 2 O 6 is an excellent alternative to dissolving the Cs-loaded or Cs-eluted exchangers in borosilicate glass because: CsTiSi 2 O 6 is formed using a simple, one step heat treatment. The unique crystalline pollucite-like structure of CsTiSi 2 O 6 traps Cs, and exhibits extremely low Cs leach rates. CsTiSi 2 O 6 is converted to solid waste at a low processing temperature of 700 to 800 C (nominal melter operating temperatures are 1150 C). CsTiSi 2 0 6 concentrates the waste, thus generating lower volumes of expensive HLW. Cs losses due to volatilization during processing of CsTiSi 2 O 6 are extremely low

  8. Synthetic inorganic ion-exchange materials

    International Nuclear Information System (INIS)

    Abe, M.

    1979-01-01

    Exchange isotherms for hydrogen ion/alkali metal ions have been measured at 20 and 40 0 C, with a solution ionic strength of 0.1, in crystalline antimonic(V) acid as a cation-exchanger. The isotherms showed S-shaped curves for the systems of H + /Na + , H + /K + , H + /Rb + and H + /Cs + , but not for H + /Li + exchange. The selectivity coefficients (logarithm scale) vs equivalent fraction of alkali metal ions in the exchanger give linear functions for all systems studied. The selectivity sequences are shown. Overall and hypothetical (zero loading) thermodynamic equilibrium constants were evaluated for these ion-exchange reactions. (author)

  9. Ion exchange and hydrolysis reactions in zeolites

    International Nuclear Information System (INIS)

    Harjula, Risto.

    1993-09-01

    Among other uses, zeolites are efficient cation exchangers for aquatic pollution control. At present they they are mainly used in nuclear waste effluent treatment and in detergency. In the thesis, several ion exchange equilibria, important in these main fields of zeolite applications, were studied, with special emphasis on the formulation and calculation of the equilibria. The main interest was the development of thermodynamic formulations for the calculation of zeolite ion exchange equilibria in solutions of low or very low (trace) ion concentration, which are relevant for the removal of trace pollutants, such as radionuclides, from waste waters. Two groups of zeolite-cation systems were studied. First, binary Ca 2+ /Na + exchange in zeolites X and Y, which are of interest for detergency applications. Second, binary Cs + /Na + and Cs + /K + exchanges, and ternary Cs + /Na + /K + exchange in mordenite, which are important in nuclear waste effluent treatment. The thesis is based on five previous publications by author. (100 refs., 7 figs.)

  10. Theoretical study of the Cs isotope exchange reaction of CsI + Cs' → Cs + ICs' (Contract research)

    International Nuclear Information System (INIS)

    Kobayashi, Takanori; Hashimoto, Masashi; Yokoyama, Keiichi

    2015-12-01

    To discuss the exchange reaction of Cs isotope by CsI + Cs' → Cs + ICs', the structure and chemical properties of Cs 2 I intermediate and potential energy surface of the entrance reaction are calculated using M06/def2-TZVPPD density functional calculation. The calculation shows that the reaction to the intermediate has no barrier and the two Cs-I bonds of Cs 2 I are chemically equivalent. These results suggest that the rate of the Cs exchange reaction of CsI + Cs' → Cs + ICs' is as high as the collision rate. (author)

  11. Outlook for ion exchange

    International Nuclear Information System (INIS)

    Kunin, R.

    1977-01-01

    This paper presents the history and theory of ion exchange technology and discusses the usefulness of ion exchange resins which found broad applications in chemical operations. It is demonstrated that the theory of ion exchange technology seems to be moving away from the physical chemist back to the polymer chemist where it started originally. This but confronted the polymer chemists with some knotty problems. It is pointed out that one has still to learn how to use ion exchange materials as efficiently as possible in terms of the waste load that is being pumped into the environment. It is interesting to note that, whereas ion exchange is used for abating pollution, it is also a polluter. One must learn how to use ion exchange as an antipollution device, and at the same time minimize its polluting properties

  12. Ion-exchange properties of natural mordenite

    International Nuclear Information System (INIS)

    Chelishchev, N.F.; Volodin, V.F.

    1977-01-01

    Ion exchange properties are studied of natural mordenite Si(Al=4.75) exhibiting adequate mechanical characteristics and sufficient resistance to high temperature acids. Consideration is given to the pattern of exchange ions distribution among mordenite and chloride solutions of K, Cs, Rb, Sr. Mordenite shows sharp selectivity towards large alkali metal cations, particularly Cs + . In these processes the exchange isotherms are characterized by the constant selectivity towards a counterion. For the Sr 2+ -2Na + exchange the isotherm shows a change of selectivity after a definite counterion concentration has been reached in the solution. Correlation between the exchange thermodynamic constants makes it possible to propose the following range of mordenite selectivity towards the cations under study: Cs>Rb>K>Na>Sr

  13. Development of rapid universal method for determination of Cs-137 in different environmental samples by means of inorganic ion exchangers. Part of a coordinated programme on radiological and environmental protection studies in the Danube river catchment area

    International Nuclear Information System (INIS)

    Radicheva, M.

    1983-02-01

    Using three synthetic inorganic ion exchangers of the same type - X 2 [YFe (CN) 6 ] (when X=alkali metal, Y=transition metal) one simple and universal rapid method for determination of Cs-137 in environmental samples was developed. The investigations carried out on synthesis, next preparation and practical use in routine analysis showed that K[CoFe(CN) 6 ] (abbr.KCFC-II) is the most suitable for analysis of low level activities of Cs-137 in different environmental samples. The optimum conditions for routine use of KCFC-II in different separation schemes were found. Repeated analysis of Cs-137 in different environmental samples as well as analysis of IAEA-Reference Materials using our rapid and one classical method showed good agreement of the results. The proposed rapid method can be used in emergency situations and in routine radiation control. (author)

  14. Research of thermal stability of ion exchangers

    International Nuclear Information System (INIS)

    Stuchlik, S.; Srnkova, J.

    1983-01-01

    Prior to the fixation of radioactive ion exchangers into bitumen these exchangers have to be dried. The resulting gaseous products may generate explosive mixtures. An analysis was made of the thermal stability of two types of ion exchangers, the cation exchanger KU-2-8 cS and the anion exchanger AV-17-8 cS which are used in the V-1 nuclear power plant at Jaslovske Bohunice. The thermal stability of the anion exchangers was monitored using gas chromatography at temperatures of 100, 120, 140, 160 and 180 degC and by measuring weight loss by kiln-drying at temperatures of 120, 140, 160 and 180 degC. The ion exchanger was heated for 6 hours and samples were taken continuously at one hour intervals. The thermal stability of the cation exchanger was monitored by measuring the weight loss. Gas chromatography showed the release of trimethylamine from the anion exchanger in direct dependence on temperature. The measurement of weight losses, however, only showed higher losses of released products which are explained by the release of other thermally unstable products. The analysis of the thermal stability of the cation exchanger showed the release of SO 2 and the weight loss (following correction for water content) was found only after the fourth hour of decomposition. The experiment showed that the drying of anion exchanger AV-17-8 cS may cause the formation of explosive mixtures. (J.P.)

  15. Electrodialytic decontamination of spent ion exchange resins

    International Nuclear Information System (INIS)

    Nott, B.R.

    1982-01-01

    Development of a novel electrodialytic decontamination process for the selective removal of radioactive Cs from spent ion exchange resins containing large amounts of Li is described. The process involves passage of a dc electric current through a bed of the spent ion exchange resin in a specially designed electrodialytic cell. The radiocesium so removed from a volume of the spent resin is concentrated onto a much smaller volume of a Cs selective sorbent to achieve a significant radioactive waste volume reduction. Technical feasibility of the electrodialytic resin decontamination process has been demonstrated on a bench scale with a batch of simulated spent ion exchange resin and using potassium cobalt ferrocyanide as the Cs selective sorbent. A volume reduction factor between 10 and 17 has been estimated. The process appears to be economically attractive. Improvements in process economics can be expected from optimization of the process. Other possible applications of the EDRD process have been identified

  16. Cs+ ion source for secondary ion mass spectrometry

    International Nuclear Information System (INIS)

    Bentz, B.L.; Weiss, H.; Liebl, H.

    1981-12-01

    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.)

  17. Ion exchange phenomena

    Energy Technology Data Exchange (ETDEWEB)

    Bourg, I.C.; Sposito, G.

    2011-05-01

    Ion exchange phenomena involve the population of readily exchangeable ions, the subset of adsorbed solutes that balance the intrinsic surface charge and can be readily replaced by major background electrolyte ions (Sposito, 2008). These phenomena have occupied a central place in soil chemistry research since Way (1850) first showed that potassium uptake by soils resulted in the release of an equal quantity of moles of charge of calcium and magnesium. Ion exchange phenomena are now routinely modeled in studies of soil formation (White et al., 2005), soil reclamation (Kopittke et al., 2006), soil fertilitization (Agbenin and Yakubu, 2006), colloidal dispersion/flocculation (Charlet and Tournassat, 2005), the mechanics of argillaceous media (Gajo and Loret, 2007), aquitard pore water chemistry (Tournassat et al., 2008), and groundwater (Timms and Hendry, 2007; McNab et al., 2009) and contaminant hydrology (Chatterjee et al., 2008; van Oploo et al., 2008; Serrano et al., 2009).

  18. Separation of cesium by ion exchange columns

    International Nuclear Information System (INIS)

    Bonini, Alberto; Falcon, Marcelo F.; Devida, Claudio A.; Tadey, D.; Vaccaro, Jorge O.; Maset, Elvira

    2003-01-01

    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

  19. Application of ion exchangers

    International Nuclear Information System (INIS)

    Markhol, M.

    1985-01-01

    Existing methods of multi-element separation for radiochemical analysis are considered. The majority of existing methods is noted to be based on application of organic and inorganic ion exchangers. Distillation, coprecipitation, extraction as well as combination of the above methods are also used. Concrete flowsheets of multi-element separation are presented

  20. Analytical applications of ion exchangers

    CERN Document Server

    Inczédy, J

    1966-01-01

    Analytical Applications of Ion Exchangers presents the laboratory use of ion-exchange resins. This book discusses the development in the analytical application of ion exchangers. Organized into 10 chapters, this book begins with an overview of the history and significance of ion exchangers for technical purposes. This text then describes the properties of ion exchangers, which are large molecular water-insoluble polyelectrolytes having a cross-linked structure that contains ionic groups. Other chapters consider the theories concerning the operation of ion-exchange resins and investigate th

  1. Batch test equilibration studies examining the removal of Cs, Sr, and Tc from supernatants from ORNL underground storage tanks by selected ion exchangers

    International Nuclear Information System (INIS)

    Collins, J.L.; Egan, B.Z.; Anderson, K.K.; Chase, C.W.; Bell, J.T.

    1995-01-01

    Bench-scale batch equilibration tests have been conducted with supernatants from two underground tanks at the Melton Valley Storage Tank (MVST) Facility at Oak Ridge National Laboratory (ORNL) to determine the effectiveness of selected ion exchangers in removing cesium, strontium, and technetium. Seven sorbents were evaluated for cesium removal, nine for strontium removal, and four for technetium removal. The results indicate that granular potassium cobalt hexacyanoferrate was the most effective of the exchangers evaluated for removing cesium from the supernatants. The powdered forms of sodium titanate (NaTiO) and cystalline silicotitanate (CST) were superior in removing the strontium; however, for the sorbents of suitable particle size for column use, titanium monohydrogen phosphate (TiHP φ), sodium titanate/polyacrylonitrile (NaTiO-PAN), and titanium monohydrogen phosphate/polyacrylonitrile (TiP-PAN) gave the best results and were about equally effective. Reillex trademark 402 was the most effective exchanger in removing the technetium; however, it was only slightly more satisfactory than Reillex trademark HPQ

  2. Studies on indigenous ion exchange resins: alkali metal ions-hydrogen ion exchange equilibria

    International Nuclear Information System (INIS)

    Shankar, S.; Kumar, Surender; Venkataramani, B.

    2001-01-01

    With a view to select a suitable ion exchange resin for the removal of radionuclides (such as cesium, strontium etc.) from low level radioactive effluents, alkali metal ion -H' exchanges on nine indigenous gel- and macroporous-type and nuclear grade resins have been studied at a total ionic strength of 0.1 mol dm .3 (in the case ofCs' -H' exchange it was 0.05 mol dm .3 ). The expected theoretical capacities were not attained by all the resins for the alkali metal ions. The water content (moles/equiv.) of the fully swollen resins for different alkali metal ionic forms do not follow the usual sequence of greater the tendency of the cation to hydrate the higher the water uptake, but a reverse trend. The ion exchange isotherms (plots of equivalent fractions of the ion in resin phase, N M1 to that in solution, N M ) were not satisfactory and sorption of cations, for most of the resins, was possible only when the acidity of the solution was lowered. The variations of the selectivity coefficient, K, with N M show that the resins are highly cross linked and the selectivity sequence: Cs + >K + >Na + >Li + , obtained for all the resins indicate that hydrated ions were involved in the exchange process. However, the increase in the selectivity was not accompanied by the release of water, but unusual uptake of water, during the exchange process. The characteristics of macroporous resins were not significantly different from those of the gel-type resins. The results are discussed in terms of heterogeneity in the polymer net work, improper sulphonation process resulting in the formation of functional groups at inaccessible sites with weak acidic character and the overall lack of control in the preparation of different resins. (author)

  3. Crystalline silicotitanates -- novel commercial cesium ion exchangers

    International Nuclear Information System (INIS)

    Braun, R.; Dangieri, T.J.; Fennelly, D.J.

    1996-01-01

    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. These CST properties made them excellent candidates for treatment of solutions such as the Hanford tank supernates and other DOE radwastes. Sandia and UOP, under a Cooperative Research and Development Agreement (CRADA), developed 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 Sandia and Texas A ampersand M consists of submicron-size particles. It is not designed for column ion exchange but may be used in other applications such as batch waste processing. Data are also presented confirming the excellent stability of the commercial CSTs over a broad pH range and the high radiation stability of the exchangers. In addition, data are provided that demonstrate the high physical strength and attrition resistance of IONSIV reg-sign IE-911, critical properties for column ion exchange applications

  4. Rupture Loop Annex (RLA) ion exchange vault entry and characterization

    International Nuclear Information System (INIS)

    Ham, J.E.

    1996-01-01

    This engineering report documents the entry and characterization of the Rupture Loop Annex Ion Exchange (RLAIX) Vault located near the 309 Building's Plutonium Recycle Test Reactor (PRTR). Twelve ion exchange columns were found in the vault. Some of which contained transuranics, Cs 137, and Co 60. The characterization information is necessary for future vault cleanout and column disposal

  5. Mutual influence of the Na+ and Cs+ ions during their mass electrotransport through a perfluorinated sulfocation membrane

    International Nuclear Information System (INIS)

    Zezina, E.A.; Popkov, Yu.M.; Timashev, S.F.

    1997-01-01

    It is shown that by the Na + and Cs + ions sorption equilibrium conditions in perfluorinated cation-exchange membranes from the 0.1M NaCl and 0.1M CsCl mixtures the Cs + ions are sorbed primarily. The effective self-diffusion coefficients of the Na + and Cs + ions from individual solutions within the range of 0.01-1.00 M concentrations and in the above-mentioned equimolar mixture are found. It is shown that the membranes moisture content is the determining factor for the Cs + ions electrodialysis separation fro the above-mentioned electrolytes mixture

  6. Enhanced desorption of Cs from clays by a polymeric cation-exchange agent

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Woo, E-mail: park85@gmail.com [Decontamination & Decommissioning Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon (Korea, Republic of); Kim, Bo Hyun [Decontamination & Decommissioning Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon (Korea, Republic of); Department of Chemical Engineering, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon (Korea, Republic of); Yang, Hee-Man; Seo, Bum-Kyoung [Decontamination & Decommissioning Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon (Korea, Republic of); Lee, Kune-Woo, E-mail: nkwlee@kaeri.re.kr [Decontamination & Decommissioning Research Division, Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon (Korea, Republic of)

    2017-04-05

    Highlights: • A cationic polyelectrolyte has excellent ability to desorb Cs bound strongly to clay. • The polycation desorbed significantly more Cs from the clay than did single cations. • Additional NH{sub 4}{sup +} treatment following the polycation treatment enhanced desorption of Cs. • The reaction yielded efficient desorption (95%) of an extremely low concentration of Cs-137 in the clay. - Abstract: We report on a new approach to increase the removal of cesium from contaminated clays based on the intercalation of a cationic polyelectrolyte into the clay interlayers. A highly charged cationic polyelectrolyte, polyethyleneimine (PEI), was shown to intercalate into the negatively charged interlayers and readily replaced Cs ions adsorbed on the interlayers of montmorillonite. The polycation desorbed significantly more Cs strongly bound to the clay than did single cations. Moreover, additional NH{sub 4}{sup +} treatment following the PEI treatment enhanced desorption of Cs ions that were less accessible by the bulky polyelectrolyte. This synergistic effect of PEI with NH{sub 4}{sup +} yielded efficient desorption (95%) of an extremely low concentration of radioactive {sup 137}Cs in the clay, which is very difficult to remove by simple cation-exchange methods due to the increased stability of the binding of Cs to the clay at low Cs concentrations.

  7. A novel vanadosilicate with hexadeca-coordinated Cs+ ions as a highly effective Cs+ remover

    International Nuclear Information System (INIS)

    Datta, Shuvo Jit; Moon, Won Kyung; Choi, Do Young; Hwang, In Chul; Yoon, Kyung Byung

    2014-01-01

    The effective removal of 137 Cs + ions from contaminated groundwater and seawater and from radioactive nuclear waste solutions is crucial for public health and for the continuous operation of nuclear power plants. Various 137 Cs + removers have been developed, but more effective 137 Cs + removers are still needed. A novel microporous vanadosilicate with mixed-valence vanadium (V 4+ and V 5+ ) ions is now reported, which shows an excellent ability for Cs + capture and immobilization from groundwater, seawater, and nuclear waste solutions. This material is superior to other known materials in terms of selectivity, capacity, and kinetics, and at very low Cs + concentrations, it was found to be the most effective material for the removal of radioactive Cs + ions under the test conditions. This novel vanadosilicate also contains hexadeca-coordinated Cs + ions, which corresponds to the highest coordination number ever described.

  8. Ion exchange in ZSM-5 zeolite

    International Nuclear Information System (INIS)

    Matthews, D.P.; Rees, L.V.C.

    1986-01-01

    The ion exchange properties of Na-ZSM5 have been studied using a number of univalent and divalent cations at 25degC and 65degC. All the univalent cations studied achieved 100 per cent exchange. The thermodynamic affinity sequence Cs > Rb=NH 4 =H 3 O>K>Na>Li was found at both temperatures for a sample with Si/Al=39. Standard enthalpies of exchange ΔH o were calculated using the van't' Hoff isochore and standard entropies of exchange were then calculated from ΔH o and ΔG o . Multivalent cations were unable to achieve 100 per cent exchange. The maximum exchange was found to increase through the series Ca 2+ cations ( 57 Fe enriched) on dehydration and rehydration following sorption and desorption of ethanol. At least 3 sites for Fe 2+ were observed in the dehydrated zeolite. (author)

  9. Contact isotopic- and contact ion-exchange between two adsorbents

    International Nuclear Information System (INIS)

    Bunzl, K.; Mohan, R.; Haimerl, M.

    1975-01-01

    The kinetics of contact ion exchange processes between an ion exchange membrane and resin ion exchange beads, stirred in pure water, was investigated. A general criterion was derived, which indicates whether diffusion of the ions between the intermingling electric double layers or the collision frequency between the two adsorbents is the rate dermining step. Since the latter process proved to be rate controlling under our experimental conditions, the corresponding rate equations were derived under various initial and boundary conditions. Experimentally, the kinetics of contact isotopic exchange of Cs + - and Na + -ions as well as of the reverse contact ion exchange process of Cs + -versus Na + -ions were investigated by using Na 22 and Cs 137 radioisotopes. The experiments reveal in quantitative accord with the theory that the rate of collision controlled contact ion exchange processes depends mainly on the 'exchange coefficient', the separation factor and the collision frequency. While the latter two quantities were determined independently by separate experiments, the 'exchange coefficient' was evaluated from a contact isotopic exchange experiment. (orig.) [de

  10. A study on dry decontamination using ion exchange polymer

    International Nuclear Information System (INIS)

    Jung, Ki Jung; Ahn, Byung Gil

    1997-12-01

    Through the project of A study on dry decontamination using ion exchange polymer , the followings were investigated. 1. Highly probable decontamination technologies for the decontamination were investigated. 2. Development of gel type decontamination agent using ion-exchange resin powder (mixed type) as an ion exchanger. 3. Manufacturing of contaminated specimens (5 kinds) with Cs-137 solution and dust / Cs-137 solution. 4. Decontamination performance evaluation of the manufactured agent. 5. Analysis of composition (XRF) and the structure of surface of specimens (optic micrography). (author). 20 refs., 11 figs

  11. Inorganic ion exchangers for nuclear waste remediation

    Energy Technology Data Exchange (ETDEWEB)

    Clearfield, A.; Bortun, A.; Bortun, L.; Behrens, E. [Texas A& M Univ., College Station, TX (United States)

    1997-10-01

    The objective of this work is to provide a broad spectrum of inorganic ion exchangers that can be used for a range of applications and separations involving remediation of groundwater and tank wastes. The authors intend to scale-up the most promising exchangers, through partnership with AlliedSignal Inc., to provide samples for testing at various DOE sites. While much of the focus is on exchangers for removal of Cs{sup +} and Sr{sup 2+} from highly alkaline tank wastes, especially at Hanford, the authors have also synthesized exchangers for acid wastes, alkaline wastes, groundwater, and mercury, cobalt, and chromium removal. These exchangers are now available for use at DOE sites. Many of the ion exchangers described here are new, and others are improved versions of previously known exchangers. They are generally one of three types: (1) layered compounds, (2) framework or tunnel compounds, and (3) amorphous exchangers in which a gel exchanger is used to bind a fine powder into a bead for column use. Most of these exchangers can be regenerated and used again.

  12. Highly Emissive Divalent-Ion-Doped Colloidal CsPb1-xMxBr3 Perovskite Nanocrystals through Cation Exchange

    NARCIS (Netherlands)

    Van der Stam, Ward; Geuchies, Jaco J.; Altantzis, Thomas; Van Den Bos, Karel H.W.; Meeldijk, Johannes D.; Van Aert, Sandra; Bals, Sara; Vanmaekelbergh, Daniel; De Mello Donega, Celso

    2017-01-01

    Colloidal CsPbX3 (X = Br, Cl, and I) perovskite nanocrystals (NCs) have emerged as promising phosphors and solar cell materials due to their remarkable optoelectronic properties. These properties can be tailored by not only controlling the size and shape of the NCs but also postsynthetic composition

  13. On the mechanism of ion exchange in zirconium phosphates

    International Nuclear Information System (INIS)

    Kullberg, L.; Clearfield, A.

    1981-01-01

    An equilibrium study of the Na + -Cs + -H + exchange on crystalline α-zirconium phosphate has been carried out. Isotherms for the ion exchange have been determined and phases formed during the exchange have been identified. The surface groups of the exchanger were found to greatly prefer cesium to sodium. For exchange in the interior, cesium was found to be preferred to sodium for 0 to 50% of exchange, while sodium is slightly preferred to cesium for the second half of exchange. The influence of surface equilibria on the total exchange mechanism is discussed. (author)

  14. Ion exchange : principles and applications

    International Nuclear Information System (INIS)

    Bank, Nader; Majumdar, A.S.

    1975-01-01

    An attempt is made to provide a brief state-of-the-art review of the basic principles underlying the unit operation of ion exchange and its numerous and diverse commercial applications. A selective bibliography is provided for the benefit of the reader interested in pursuing any specific aspect of ion exchange. (author)

  15. The mechanism of ion exchange on ammonium 12-molybdophosphate (AMP)

    International Nuclear Information System (INIS)

    Boeyens, J.C.A.; McDougall, G.J.; Smit, J. van R.

    1987-01-01

    This paper reviews some published and unpublished data on the ion-exchange properties of AMP. The three NH 4 + ions are only partially exchanged for large monovalent ions. In the case of NH 4 + /K + exchange, the energy lost by the breaking of H bonds between the NH 4 + ions and anionic cage oxygen atoms beyond the point of maximum exchange is no longer compensated for by bond strengthening in the anion due to contraction of the cage. With Rb + , Cs + and T1 + , limited convertibility results from the lattice expansion required to accommodate these larger ions. During exchange, part of the cations pass through the anionic cages, thereby causing considerable lattice disorder. The maximum exchange capacity of AMP for the alkali metal ions is not a simple function of cation radius. (author)

  16. Solidification of ion exchange resin wastes

    International Nuclear Information System (INIS)

    1982-08-01

    Solidification media investigated included portland type I, portland type III and high alumina cements, a proprietary gypsum-based polymer modified cement, and a vinyl ester-styrene thermosetting plastic. Samples formulated with hydraulic cement were analyzed to investigate the effects of resin type, resin loading, waste-to-cement ratio, and water-to-cement ratio. The solidification of cation resin wastes with portland cement was characterized by excessive swelling and cracking of waste forms, both after curing and during immersion testing. Mixed bed resin waste formulations were limited by their cation component. Additives to improve the mechanical properties of portland cement-ion exchange resin waste forms were evaluated. High alumina cement formulations dislayed a resistance to deterioration of mechanical integrity during immersion testing, thus providing a significant advantage over portland cements for the solidification of resin wastes. Properties of cement-ion exchange resin waste forms were examined. An experiment was conducted to study the leachability of 137 Cs, 85 Sr, and 60 Co from resins modified in portland type III and high alumina cements. The cumulative 137 Cs fraction release was at least an order of magnitude greater than that of either 85 Sr or 60 Co. Release rates of 137 Cs in high alumina cement were greater than those in portland III cement by a factor of two.Compressive strength and leach testing were conducted for resin wastes solidified with polymer-modified gypsum based cement. 137 Cs, 85 Sr, and 60 Co fraction releases were about one, two and three orders of magnitude higher, respectively, than in equivalent portland type III cement formulations. As much as 28.6 wt % dry ion exchange resin was successfully solidified using vinyl ester-styrene compared with a maximum of 25 wt % in both portland and gypsum-based cement

  17. Ion exchange of natural natrolite in melted salts

    International Nuclear Information System (INIS)

    Faghihian, H.; Nekuei, P.

    2007-01-01

    In this research the ion exchange potential of natrolite towards K + , TI + , Cs +2 , Ca +2 , Ni +2 , Cu 2+ , and Co 2+ in their melted salts was investigated. The effect of temperature, reaction time and zeolite to salt ratio on the exchange relation was studied. The exchange of ca 2+ , Ni 2+ , cu 2+ , and Co 2+ was negligible and was equal to 2.59, 6.29, 3.14 and 5.04 percent respectively whereas the exchange of K + , Tl + , Cs + was relatively high and equal to 82.36,66.67 and 42.98 percent respectively

  18. Progress in liquid ion exchangers

    International Nuclear Information System (INIS)

    Nakagawa, Genkichi

    1974-01-01

    Review is made on the extraction with anion exchangers and the extraction with liquid cation exchangers. On the former, explanation is made on the extraction of acids, the relation between anion exchange and the extraction of metals, the composition of the metallic complexes that are extracted, and the application of the extraction with anion exchangers to analytical chemistry. On the latter, explanation is made on the extraction of metals and its application to analytical chemistry. The extraction with liquid ion exchangers is suitable for the operation in chromatography, because the distribution of extracting agents into aqueous phase is small, and extraction equilibrium is quickly reached, usually within 1 to several minutes. The separation by means of anion exchangers is usually made from hydrochloric acid solution. For example, Brinkman et al. determined Rf values for more than 50 elements by thin layer chromatography. Tables are given for showing the structure of the liquid ion exchangers and the polymerized state of various amines. (Mori, K.)

  19. Waste separation and pretreatment using crystalline silicotitanate ion exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Tadros, M.E.; Miller, J.E. [Sandia National Lab., Albuquerque, NM (United States); Anthony, R.G. [Texas A& M Univ., College Station, TX (United States)

    1997-10-01

    A new class of inorganic ion exchangers called crystalline silicotitanates (CSTs) has been developed jointly by Sandia National Laboratories and Texas A&M University to selectively remove Cs and other radionuclides from a wide spectrum of radioactive defense wastes. The CST exhibits high selectivity and affinity for Cs and Sr under a wide range of conditions. Tests show it can remove part-per-million concentrations of Cs{sup +} from highly alkaline, high-sodium simulated radioactive waste solutions modeled after those at Hanford, Oak Ridge, and Savannah River. The materials exhibit ion exchange properties based on ionic size selectivity. Specifically, crystalline lattice spacing is controlled to be highly selective for Cs ions even in waste streams containing very high (5 to 10 M) concentrations of sodium. The CST technology is being demonstrated with actual waste at several DOE facilities. The use of inorganic ion exchangers. The inorganics are more resistant to chemical, thermal, and radiation degradation. Their high selectivities result in more efficient operations offering the possibility of a simple single-pass operation. In contrast, regenerable organic ion exchangers require additional processing equipment to handle the regeneration liquids and the eluant with the dissolved Cs.

  20. Electrically switched cesium ion exchange

    International Nuclear Information System (INIS)

    Lilga, M.A.; Orth, R.J.; Sukamto, J.P.H.; Schwartz, D.T.; Haight, S.M.; Genders, J.D.

    1997-04-01

    Electrically Switched Ion Exchange (ESIX) is a separation technology being developed as an alternative to conventional ion exchange for removing radionuclides from high-level waste. 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 are 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. A case study for the KE Basin on the Hanford Site was conducted based on the results of the development testing. Engineering design baseline parameters for film deposition, film regeneration, cesium loading, and cesium elution were used for developing a conceptual system. Order of magnitude cost estimates were developed to compare with conventional ion exchange. This case study demonstrated that KE Basin wastewater could be processed continuously with minimal secondary waste and reduced associated disposal costs, as well as lower capital and labor expenditures

  1. Ion Exchange Properties of Georgian Natural Zeolites

    Directory of Open Access Journals (Sweden)

    Vladimer Tsitsishvili

    2017-06-01

    Full Text Available Ion-exchange properties of natural zeolites of Georgia with a relatively low Si/Al ratio have been studied: analcimes are characterized by selectivity series: Na+>K+>Ag+>NH4+>Ca+2>Sr+2>Li+; for phillipsites selectivity sequences are different for calcium- and potassium forms; selectivity sequence for scolecite is: Sr+2>Ba+2>Rb+>Ca+2>Cs+>K+>NH4+>Na+>Mg+2>Li+>Cd+2>Cu+2> Mn+2> Zn+2>Co+2>Ni+2.

  2. Study of ion exchange equilibrium and determination of heat of ion exchange by ion chromatography

    International Nuclear Information System (INIS)

    Liu Kailu; Yang Wenying

    1996-01-01

    Ion chromatography using pellicularia ion exchange resins and dilute solution can be devoted to the study of ion exchange thermodynamics and kinetics. Ion exchange equilibrium equation was obtained, and examined by the experiments. Based on ion exchange equilibrium, the influence of eluent concentration and resin capacity on adjusted retention volumes was examined. The effect of temperature on adjusted retention volumes was investigated and heats of ion exchange of seven anions were determined by ion chromatography. The interaction between anions and skeleton structure of resins were observed

  3. Electrodialytic separation of alkali-element ions with the aid of ion-exchange membranes

    International Nuclear Information System (INIS)

    Gurskii, V.S.; Moskvin, L.N.

    1988-01-01

    Electrodialytic separation of ions bearing charges of the same sign with the aid of ion-exchange membranes has been examined in the literature in relation to the so-called ideal membranes, which do not exhibit selectivity with respect to one ion type in ion exchange. It has been shown that separation on such membranes is effective only for counterions differing in size of charge. A matter of greater importance from the practical standpoint is the possibility of using electrodialysis for separating ions bearing like charges and having similar properties, including ionic forms of isotopes of the same element. In this paper they report a comparative study of ion separation, with reference to the Cs-Na pair, by electrodialysis through various types of cation-exchange membranes. Changes of the solution concentration in the cathode compartment were monitored by measurement of 22 Na and 137 Cs activities

  4. Disposal of bead ion exchange resin wastes

    International Nuclear Information System (INIS)

    Gay, R.L.; Granthan, L.F.

    1985-01-01

    Bead ion exchange resin wastes are disposed of by a process which involves spray-drying a bead ion exchange resin waste in order to remove substantially all of the water present in such waste, including the water on the surface of the ion exchange resin beads and the water inside the ion exchange resin beads. The resulting dried ion exchange resin beads can then be solidified in a suitable solid matrix-forming material, such as a polymer, which solidifies to contain the dried ion exchange resin beads in a solid monolith suitable for disposal by burial or other conventional means

  5. The study on the ion exchange behavior of metal ions using composite ion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kukki; Lee, Kunjai [Nuclear Engineering Department Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Kim, Youngkyun [Korea Institute of Nuclear Safety, Daejon (Korea, Republic of); Lee, Sangjin; Yang, Hoyeon; Ha, Jonghyun [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2002-04-15

    In this study, a series of stepwise procedures to prepare a new organic-inorganic composite magnetic resin with phenol sulphonic-formaldehyde and freshly formed iron ferrite was established, based upon wet-and-neutralization method for synthesizing iron ferrite and pearl-polymerization method for synthesizing rigid bead-type composite resin. And a separation of metal ions in the liquid radioactive waste have been performed using organic-inorganic composite magnetic resin with phenol sulphonic-formaldehyde and freshly formed iron ferrite. The PSF-F (phenol sulphonic formaldehyde-iron ferrite) composite resin prepared by the above method shows stably high removal efficiency to Co(II), Fe, Cs species from wastewater in a wide range of solution pH. The wide range of applicable solution pH (i. e. pH 4.0 to 10.3) implies that the PSF-F composite resin overcomes the limitations of the conventional ferrite process which is practically applicable only to alkaline conditions. The experiment proceeded using batch reactor in a constant temperature with water bath. The experiments divided into three parts. The first one is TG/DTA (Thermogravimetry / Differential Thermal Analysis) which can analyze the trend of pyrolysis of PSF-F ion exchanger. The Second one is equilibrium experiment in which the separation factor of metal ions and Langmuir, Freundlich isotherm was achieved. The last one is kinetics experiment in which the equilibrium reaction time and removal efficiency is estimated.

  6. The study on the ion exchange behavior of metal ions using composite ion exchange resin

    International Nuclear Information System (INIS)

    Kim, Kukki; Lee, Kunjai; Kim, Youngkyun; Lee, Sangjin; Yang, Hoyeon; Ha, Jonghyun

    2002-01-01

    In this study, a series of stepwise procedures to prepare a new organic-inorganic composite magnetic resin with phenol sulphonic-formaldehyde and freshly formed iron ferrite was established, based upon wet-and-neutralization method for synthesizing iron ferrite and pearl-polymerization method for synthesizing rigid bead-type composite resin. And a separation of metal ions in the liquid radioactive waste have been performed using organic-inorganic composite magnetic resin with phenol sulphonic-formaldehyde and freshly formed iron ferrite. The PSF-F (phenol sulphonic formaldehyde-iron ferrite) composite resin prepared by the above method shows stably high removal efficiency to Co(II), Fe, Cs species from wastewater in a wide range of solution pH. The wide range of applicable solution pH (i. e. pH 4.0 to 10.3) implies that the PSF-F composite resin overcomes the limitations of the conventional ferrite process which is practically applicable only to alkaline conditions. The experiment proceeded using batch reactor in a constant temperature with water bath. The experiments divided into three parts. The first one is TG/DTA (Thermogravimetry / Differential Thermal Analysis) which can analyze the trend of pyrolysis of PSF-F ion exchanger. The Second one is equilibrium experiment in which the separation factor of metal ions and Langmuir, Freundlich isotherm was achieved. The last one is kinetics experiment in which the equilibrium reaction time and removal efficiency is estimated

  7. SPEEDUPtrademark ion exchange column model

    International Nuclear Information System (INIS)

    Hang, T.

    2000-01-01

    A transient model to describe the process of loading a solute onto the granular fixed bed in an ion exchange (IX) column has been developed using the SpeedUptrademark software package. SpeedUp offers the advantage of smooth integration into other existing SpeedUp flowsheet models. The mathematical algorithm of a porous particle diffusion model was adopted to account for convection, axial dispersion, film mass transfer, and pore diffusion. The method of orthogonal collocation on finite elements was employed to solve the governing transport equations. The model allows the use of a non-linear Langmuir isotherm based on an effective binary ionic exchange process. The SpeedUp column model was tested by comparing to the analytical solutions of three transport problems from the ion exchange literature. In addition, a sample calculation of a train of three crystalline silicotitanate (CST) IX columns in series was made using both the SpeedUp model and Purdue University's VERSE-LC code. All test cases showed excellent agreement between the SpeedUp model results and the test data. The model can be readily used for SuperLigtrademark ion exchange resins, once the experimental data are complete

  8. Ion exchange purification of scandium

    Science.gov (United States)

    Herchenroeder, Laurie A.; Burkholder, Harvey R.

    1990-10-23

    An improvement in purification of scandium through ion exchange chromatography is disclosed in which the oxidation potential of the eluting solution is altered by the addition of potassium chlorate or ammonium chloride so that removal of contaminants is encouraged. The temperature, pH and concentration of the eluent HEDTA are controlled in order to maintain the scandium in the column while minimizing dilution of the scandium band. Recovery of scandium is improved by pumping dilute scandium over the column prior to stripping the scandium and precipitation. This eliminates the HEDTA ion and other monovalent cations contaminating the scandium band. This method maximizes recovery of scandium while maintaining purity.

  9. 225-B ion exchange piping design documentation

    International Nuclear Information System (INIS)

    Prather, M.C.

    1996-02-01

    This document describes the interface between the planned permanent ion exchange piping system and the planned portable ion exchange system. This is part of the Waste Encapsulation and Storage Facility (WESF). In order to decouple this WESF from B-Plant and to improve recovery from a capsule leak, contaminated pool cell water will be recirculated through a portable ion exchange resin system

  10. Ion-exchange chromatographic protein refolding

    NARCIS (Netherlands)

    Freydell, E.; Wielen, van der L.; Eppink, M.H.M.; Ottens, M.

    2010-01-01

    The application of ion-exchange (IEX) chromatography to protein refolding (IExR) has been successfully proven, as supported by various studies using different model proteins, ion-exchange media and flow configurations. Ion-exchange refolding offers a relatively high degree of process

  11. Postsynthetic Doping of MnCl2 Molecules into Preformed CsPbBr3 Perovskite Nanocrystals via a Halide Exchange-Driven Cation Exchange.

    Science.gov (United States)

    Huang, Guangguang; Wang, Chunlei; Xu, Shuhong; Zong, Shenfei; Lu, Ju; Wang, Zhuyuan; Lu, Changgui; Cui, Yiping

    2017-08-01

    Unlike widely used postsynthetic halide exchange for CsPbX 3 (X is halide) perovskite nanocrystals (NCs), cation exchange of Pb is of a great challenge due to the rigid nature of the Pb cationic sublattice. Actually, cation exchange has more potential for rendering NCs with peculiar properties. Herein, a novel halide exchange-driven cation exchange (HEDCE) strategy is developed to prepare dually emitting Mn-doped CsPb(Cl/Br) 3 NCs via postsynthetic replacement of partial Pb in preformed perovskite NCs. The basic idea for HEDCE is that the partial cation exchange of Pb by Mn has a large probability to occur as a concomitant result for opening the rigid halide octahedron structure around Pb during halide exchange. Compared to traditional ionic exchange, HEDCE is featured by proceeding of halide exchange and cation exchange at the same time and lattice site. The time and space requirements make only MnCl 2 molecules (rather than mixture of Mn and Cl ions) capable of doping into perovskite NCs. This special molecular doping nature results in a series of unusual phenomenon, including long reaction time, core-shell structured mid states with triple emission bands, and dopant molecules composition-dependent doping process. As-prepared dual-emitting Mn-doped CsPb(Cl/Br) 3 NCs are available for ratiometric temperature sensing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. New sorbents and ion exchangers for nuclear waste solution remediation

    International Nuclear Information System (INIS)

    Clearfield, A.; Peng, G.Z.; Cahill, R.A.; Bellinghausen, P.; Aly, H.I.; Scott, K.; Wang, J.D.

    1993-01-01

    There is now a concerted effort underway to clean up the accumulated nuclear wastes as the major sites around the country. Because of the complexity of the mixtures in the holding tanks highly specific exchangers are required to fulfill a multitude of desired tasks. These include removal of Cs + , Sr 2+ , Tc, Actinides and possible recovery of rare and precious metals. No one exchanger or sequestrant can accomplish these tasks and a variety of exchangers in a multistep process will be required. The behavior of a number of inorganic ion exchangers in a multistep process will be required. The behavior of a number of inorganic ion exchangers and new organo-inorganic exchangers towards Cs + , Sr 2+ and rare-earth ions in acid and basic media will be described. Preliminary data on the effect of high levels of sodium nitrate on the uptake of these ions will also be presented, as well as the changes observed in selectivity in simulated waste solutions. A possible separation scheme based on these data will be described

  13. Desorption of Cs+ ions with fast incident atomic and molecular ions

    International Nuclear Information System (INIS)

    Salehpour, M.; Hunt, J.E.; Tou, L.C.; Hedin, A.; Sundqvist, B.

    1988-01-01

    Preliminary results on desorption yield measurements of secondary Cs + ions, desorbed as a result of the impact of C + , O + , CO + , O 2 + , CO 2 + and C 4 H 9 + incident ions, in the energy range of 950 keV--3.5 MeV are presented. Molecular beams are found to give high yields of secondary Cs + as a result of impact of O 2 + compared to O + incident ions, indicate no ''collective'' molecular effects. 23 refs., 1 fig

  14. Multicomponent liquid ion exchange with chabazite zeolites

    International Nuclear Information System (INIS)

    Robinson, S.M.; Arnold, W.D. Jr.; Byers, C.W.

    1993-10-01

    In spite of the increasing commercial use of zeolites for binary and multicomponent sorption, the understanding of the basic mass-transfer processes associated with multicomponent zeolite ion-exchange systems is quite limited. This study was undertaken to evaluate Na-Ca-Mg-Cs-Sr ion exchange from an aqueous solution using a chabazite zeolite. Mass-transfer coefficients and equilibrium equations were determined from experimental batch-reactor data for single and multicomponent systems. The Langmuir isotherm was used to represent the equilibrium relationship for binary systems, and a modified Dubinin-Polyani model was used for the multicomponent systems. The experimental data indicate that diffusion through the microporous zeolite crystals is the primary diffusional resistance. Macropore diffusion also significantly contributes to the mass-transfer resistance. Various mass-transfer models were compared to the experimental data to determine mass-transfer coefficients. Effective diffusivities were obtained which accurately predicted experimental data using a variety of models. Only the model which accounts for micropore and macropore diffusion occurring in series accurately predicted multicomponent data using single-component diffusivities. Liquid and surface diffusion both contribute to macropore diffusion. Surface and micropore diffusivities were determined to be concentration dependent

  15. Treatment of radioactive wastewaters by chemical precipitation and ion exchange

    International Nuclear Information System (INIS)

    Robinson, S.M.; Begovich, J.M.; Brown, C.H. Jr.; Campbell, D.O.; Collins, E.D.

    1987-01-01

    Precipitation and ion exchange methods are being developed at Oak Ridge National Laboratory to decontaminate wastewaters containing small amounts of 90 Sr and 137 Cs while minimizing waste generation. Distribution coefficients have been determined for strontium and cesium as functions of Ca, Na, and Mg concentrations from bench- and pilot-scale data for ion exchange resins and zeolites using actual wastewaters. Models have been used to estimate the total amount of waste that would be generated at full-scale operation. Based on these data, four process flowsheets are being tested at full-scale. 14 refs., 8 figs., 7 tabs

  16. PRTR ion exchange vault column sampling

    International Nuclear Information System (INIS)

    Cornwell, B.C.

    1995-01-01

    This report documents ion exchange column sampling and Non Destructive Assay (NDA) results from activities in 1994, for the Plutonium Recycle Test Reactor (PRTR) ion exchange vault. The objective was to obtain sufficient information to prepare disposal documentation for the ion exchange columns found in the PRTR Ion exchange vault. This activity also allowed for the monitoring of the liquid level in the lower vault. The sampling activity contained five separate activities: (1) Sampling an ion exchange column and analyzing the ion exchange media for purpose of waste disposal; (2) Gamma and neutron NDA testing on ion exchange columns located in the upper vault; (3) Lower vault liquid level measurement; (4) Radiological survey of the upper vault; and (5) Secure the vault pending waste disposal

  17. Laser Decontamination of Surfaces Contaminated with Cs+ Ion

    International Nuclear Information System (INIS)

    Baigalmaaa, B.; Won, H. J.; Moon, J. K.; Jung, C. H.; Lee, K. W.; Hyun, J. H.

    2008-01-01

    Laser decontamination technology has been proven to be an efficient method for a surface modification of metals and concretes contaminated with radioactive isotopes. Furthermore, the generation of a secondary waste is negligible. The radioactivity of hot cells in the DFDF (Dupic Fuel Development Facility) is presumed to be very high and the predominant radionuclide is Cs-137. A series of laser decontamination studies by a fabricated Q-switched Nd:YAG laser system were performed on stainless steel specimens artificially contaminated with Cs+ ion. Decontamination characteristics of the stainless steel were analyzed by SEM and EPMA

  18. Ion exchange for glass strengthening

    International Nuclear Information System (INIS)

    Gy, Rene

    2008-01-01

    This paper presents a short overview of silicate glass strengthening by exchange of alkali ions in a molten salt, below the glass transition temperature (chemical tempering). The physics of alkali inter-diffusion is briefly explained and the main parameters of the process, which control the glass reinforcement, are reviewed. Methods for characterizing the obtained residual stress state and the strengthening are described, along with the simplified modelling of the stress build-up. The fragmentation of chemically tempered glass is discussed. The concept of engineered stress profile glass is presented, and finally, the effect of glass and salt compositions is overviewed

  19. Surface- vs Diffusion-Limited Mechanisms of Anion Exchange in CsPbBr3 Nanocrystal Cubes Revealed through Kinetic Studies.

    Science.gov (United States)

    Koscher, Brent A; Bronstein, Noah D; Olshansky, Jacob H; Bekenstein, Yehonadav; Alivisatos, A Paul

    2016-09-21

    Ion-exchange transformations allow access to nanocrystalline materials with compositions that are inaccessible via direct synthetic routes. However, additional mechanistic insight into the processes that govern these reactions is needed. We present evidence for the presence of two distinct mechanisms of exchange during anion exchange in CsPbX3 nanocrystals (NCs), ranging in size from 6.5 to 11.5 nm, for transformations from CsPbBr3 to CsPbCl3 or CsPbI3. These NCs exhibit bright luminescence throughout the exchange, allowing their optical properties to be observed in real time, in situ. The iodine exchange presents surface-reaction-limited exchanges allowing all anionic sites within the NC to appear chemically identical, whereas the chlorine exchange presents diffusion-limited exchanges proceeding through a more complicated exchange mechanism. Our results represent the first steps toward developing a microkinetic description of the anion exchange, with implications not only for understanding the lead halide perovskites but also for nanoscale ion exchange in general.

  20. Ion exchange process: History, evolution and applications

    International Nuclear Information System (INIS)

    Mazzoldi, P.; Carturan, S.; Sada, C.; Quaranta, A.; Sglavo, V.M.

    2013-01-01

    The aim of this paper is to present a review on some aspects and applications of ion exchange process in glasses, ferroelectric and polymers in the fields of optics, nanotechnology, gas sensors and chemical strengthening. The formation of nanoparticles in ion-exchanged glasses, as effect of ion or laser irradiation, is discussed. A discussion on the potentialities of ion exchange process in comparison to ion implantation in optical devices and nanotechnology is also introduced. Analytical techniques applied to the study of the ion exchange process are illustrated. The studies of ion exchange process in “Natural materials” constitute the content of a specific paragraph, for applications in water cleaning. Some initial considerations on the “old age” of this technique are introduced.

  1. Using Ion Exchange Chromatography to Separate and Quantify Complex Ions

    Science.gov (United States)

    Johnson, Brian J.

    2014-01-01

    Ion exchange chromatography is an important technique in the separation of charged species, particularly in biological, inorganic, and environmental samples. In this experiment, students are supplied with a mixture of two substitution-inert complex ions. They separate the complexes by ion exchange chromatography using a "flash"…

  2. Ion-exchange behaviour of hydrous zirconia in mixed solvents: capacity and kinetics of exchange

    International Nuclear Information System (INIS)

    Misak, N.Z.; Ghoneimy, H.F.

    1982-01-01

    The capacity of the Li + form of hydrous zirconia for Na + and Cs + increases in the presence of methanol. This may be due to the greater stability of Li + in methanol/water than in pure water and to dehydration of Na + and Cs + and their stronger interaction with the exchange sites, which may facilitate their replacing Li + . The ion-exchange capacity of zirconia for NO 3 - , Cl - and Br - is almost the same in aqueous solution and is not affected by addition of up to 90% (v/v) methanol, which probably shows that these anions are electrostatically bound in zirconia without specific interactions. The internal diffusion coefficients of the Na + /H + and Cl - /OH - systems decrease in the presence of alcohol: the decrease is highest with methanol and similar for ethanol and propan-2-ol. This is discussed in the light of ion solvation and alcohol penetration inside zirconia. (author)

  3. The changes in the microstructure of ion-exchanged clays

    Directory of Open Access Journals (Sweden)

    Nartowska Edyta

    2017-01-01

    Full Text Available Three natural bentonites and their monoionic forms were investigated by the X-Ray Diffractometry (XRD and Scanning Electron Microscopy (SEM. SEM photographs were analysed using the Photoshop CS4 software and the pore parameters were calculated. The parameters were compared to a interplanar spacing d001 value changes between different homoionic forms. The results suggest the connection between the type of exchangeable cation with the structural parameters of the pores and physicomechanical parameters of the soil, therefore the ion exchange method could be used for controlling soil properties corresponding to their suitability for use in the industry.

  4. A Multi-Sample Cs-Sputter Negative Ion Source

    International Nuclear Information System (INIS)

    Alton, G.D.; Ball, J.A.; Bao, Y.; Cui, B.; Reed, C.A.; Williams, C.

    1998-01-01

    A multi-sample Cs sputter negative-ion source, equipped with a conical-geometry, W-surface-ionizer has been designed and fabricated that permits sample changes without disruption of on-line accelerator operation. Sample changing is effected by actuating an electro-pneumatic control system located at ground potential that drives an air-motor-driven sample-indexing-system mounted at high voltage; this arrangement avoids complications associated with indexing mechanisms that rely on electronic power-supplies located at high potential. In-beam targets are identified by LED indicator lights derived from a fiber-optic, Gray-code target-position sensor. Aspects of the overall source design and details of the indexing mechanism along with operational parameters, ion optics. intensities, and typical emittances for a variety of negative-ion species will be presented in this report

  5. A Multi-Sample Cs-Sputter Negative Ion Source

    Energy Technology Data Exchange (ETDEWEB)

    Alton, G.D.; Ball, J.A.; Bao, Y.; Cui, B.; Reed, C.A.; Williams, C.

    1998-10-05

    A multi-sample Cs sputter negative-ion source, equipped with a conical-geometry, W-surface-ionizer has been designed and fabricated that permits sample changes without disruption of on-line accelerator operation. Sample changing is effected by actuating an electro-pneumatic control system located at ground potential that drives an air-motor-driven sample-indexing-system mounted at high voltage; this arrangement avoids complications associated with indexing mechanisms that rely on electronic power-supplies located at high potential. In-beam targets are identified by LED indicator lights derived from a fiber-optic, Gray-code target-position sensor. Aspects of the overall source design and details of the indexing mechanism along with operational parameters, ion optics. intensities, and typical emittances for a variety of negative-ion species will be presented in this report.

  6. Transformation of Sintered CsPbBr3 Nanocrystals to Cubic CsPbI3 and Gradient CsPbBrxI3-x through Halide Exchange.

    Science.gov (United States)

    Hoffman, Jacob B; Schleper, A Lennart; Kamat, Prashant V

    2016-07-13

    All-inorganic cesium lead halide (CsPbX3, X = Br(-), I(-)) perovskites could potentially provide comparable photovoltaic performance with enhanced stability compared to organic-inorganic lead halide species. However, small-bandgap cubic CsPbI3 has been difficult to study due to challenges forming CsPbI3 in the cubic phase. Here, a low-temperature procedure to form cubic CsPbI3 has been developed through a halide exchange reaction using films of sintered CsPbBr3 nanocrystals. The reaction was found to be strongly dependent upon temperature, featuring an Arrhenius relationship. Additionally, film thickness played a significant role in determining internal film structure at intermediate reaction times. Thin films (50 nm) showed only a small distribution of CsPbBrxI3-x species, while thicker films (350 nm) exhibited much broader distributions. Furthermore, internal film structure was ordered, featuring a compositional gradient within film. Transient absorption spectroscopy showed the influence of halide exchange on the excited state of the material. In thicker films, charge carriers were rapidly transferred to iodide-rich regions near the film surface within the first several picoseconds after excitation. This ultrafast vectorial charge-transfer process illustrates the potential of utilizing compositional gradients to direct charge flow in perovskite-based photovoltaics.

  7. Ion exchange in the nuclear industry

    International Nuclear Information System (INIS)

    Bibler, J.P.

    1990-01-01

    Ion exchange is used in nearly every part of the nuclear fuel cycle -- from the purification of uranium from its ore to the final recovery of uranium and transmutation products. Ion exchange also plays a valuable role in the management of nuclear wastes generated in the fuel cycle

  8. Thermodynamics of H+/Cs+ exchange on amorphous zirconium phosphate in mixed solvents

    International Nuclear Information System (INIS)

    Misak, N.Z.; Mikhail, E.M.

    1983-01-01

    In aqueous, 30% isopropanol and acetone, and up to 90% methanol, the H + /Cs + exchange on zirconium phosphate is entropy directed, while in 60% isopropanol and acetone it is enthalpy directed and a selectivity reversal occurs. ΔF 0 decreases in all cases with increasing addition of the organic solvent. ΔH 0 becomes appreciably negative (ΔH 0 = 0 in aqueous medium) and ΔS 0 decreases appreciably on addition of 30% organic solvent, but they increase with further addition. In presence of methanol, ion-solvent interaction effects are counteracted by effects of solid phase interactions but the former effects predominate and lead to decrease of ΔF 0 . On going from 30 to 90 % methanol, positive enthalpy and entropy changes occur due to solid phase interactions involving probably the dehydration of the ingoing Cs + . In presence of up to 60% acetone, ΔF 0 (or selectively constant) changes mainly due to ion-solvent interactions and can be theoretically calculated from the value in the aqueous medium by use of transfer thermodynamics data. This is probably due to a limited imbibition of acetone. (author)

  9. Ion exchange in the nuclear power industry

    International Nuclear Information System (INIS)

    Lehto, J.

    1993-01-01

    Ion exchangers are used in many fields in the nuclear power industry. At nuclear power plants, organic ion exchange resins are mainly used for the removal of ionic and particulate contaminants from the primary circuit, condensate and fuel storage pond waters. Ion exchange resins are used for the solidification of low- and medium-active nuclear waste solutions. The number of applications of zeolites, and other inorganic ion exchangers, in the separation of radionuclides from nuclear waste solutions has been increasing since the 1980s. In nuclear fuel reprocessing plants, ion exchange is used for the solidification of low- and medium-active waste solutions, as well as for the partitioning of radioactive elements for further use. (Author)

  10. Improvements in and relating to ion-exchange

    International Nuclear Information System (INIS)

    Heal, H.G.

    1975-01-01

    It has been found that the relatively expensive ion exchange materials normally used can be extensively replaced by relatively inexpensive material comprised of long-weathered basalt. This has been found to effect rapid and efficient ion exchange with a capacity comparable with, and in some cases greater than, the usual artificial materials. The basalt should contain at least 50% by weight of particles of size below 3cm mesh. Olivine basalt has proved particularly effective. Examples given include removal of Cu and Co, application to water softening, and to the removal of 137 Cs from milk. Other applications mentioned include removal of Ca, 90 Sr, Pb, Zn, Hg, Ni, and Cr, extraction of metal ions from seawater, purification of industrial effluents, etc. (U.K.)

  11. Adsorption on mixtures of ion exchangers

    International Nuclear Information System (INIS)

    Triolo, R.; Lietzke, M.H.

    1979-01-01

    A theoretical study has been made of adsorption on mixtures of ion exchangers. The effect of variables such as the concentration of the ion being adsorbed, the concentration of the supporting electrolyte, loading, the values of the capacities and equilibrium constants for the various exchange processes, and the fraction of each adsorber in the mixture on the observed distribution coefficient has been investigated. A computer program has been written to facilitate the calculation of distribution coefficients for the adsorption of an ion on a given mixture of ion exchangers under a specified set of conditions

  12. Characterisation of Cs ion implanted GaN by DLTS

    Science.gov (United States)

    Ngoepe, P. N. M.; Meyer, W. E.; Auret, F. D.; Omotoso, E.; Hlatshwayo, T. T.; Diale, M.

    2018-04-01

    Deep level transient spectroscopy (DLTS) was used to characterise Cs implanted GaN grown by hydride vapour phase epitaxy (HVPE). This implantation was done at room temperature using energy of 360 keV to a fluence of 10-11 cm-2. A defect with activation energy of 0.19 eV below the conduction band and an apparent capture cross section of 1.1 × 10-15 cm2 was induced. This defect has previously been observed after rare earth element (Eu, Er and Pr) implantation. It has also been reported after electron, proton and He ion implantation.

  13. A novel vanadosilicate with hexadeca-coordinated Cs{sup +} ions as a highly effective Cs{sup +} remover

    Energy Technology Data Exchange (ETDEWEB)

    Datta, Shuvo Jit; Moon, Won Kyung; Choi, Do Young; Hwang, In Chul; Yoon, Kyung Byung [Sogang Univ., Seoul (Korea, Republic of). Korea Center for Artificial Photosynthesis

    2014-07-07

    The effective removal of {sup 137}Cs{sup +} ions from contaminated groundwater and seawater and from radioactive nuclear waste solutions is crucial for public health and for the continuous operation of nuclear power plants. Various {sup 137}Cs{sup +} removers have been developed, but more effective {sup 137}Cs{sup +} removers are still needed. A novel microporous vanadosilicate with mixed-valence vanadium (V{sup 4+} and V{sup 5+}) ions is now reported, which shows an excellent ability for Cs{sup +} capture and immobilization from groundwater, seawater, and nuclear waste solutions. This material is superior to other known materials in terms of selectivity, capacity, and kinetics, and at very low Cs{sup +} concentrations, it was found to be the most effective material for the removal of radioactive Cs{sup +} ions under the test conditions. This novel vanadosilicate also contains hexadeca-coordinated Cs{sup +} ions, which corresponds to the highest coordination number ever described.

  14. Decomposing method for ion exchange resin

    International Nuclear Information System (INIS)

    Sako, Takeshi; Sato, Shinshi; Akai, Yoshie; Moniwa, Shinobu; Yamada, Kazuo

    1998-01-01

    The present invention concerns a method of decomposing ion exchange resins generated in a nuclear power plant to carbon dioxide reliably in a short period of time. (1) The ion exchange resins are mixed with water, and then they are kept for a predetermined period of time in the presence of an inert gas at high temperature and high pressure exceeding the critical point of water to decompose the ion exchange resins. (2) The ion exchange resins is mixed with water, an oxidant is added and they are kept for a predetermined time in the presence of an inert gas at a high temperature and a high pressure exceeding a critical point of water of an inert gas at a high temperature to decompose the ion exchange resins. (3) An alkali or acid is added to ion exchange resins and water to control the hydrogen ion concentration in the solution and the ion exchange resins are decomposed in above-mentioned (1) or (2). Sodium hydroxide is used as the alkali and hydrochloric acid is used as the acid. In addition, oxygen, hydrogen peroxide or ozone is used as an oxidant. (I.S.)

  15. Inorganic ion exchangers in industrial and nuclear waste treatment

    International Nuclear Information System (INIS)

    Manosso, Helena C.; Forbicini, Christina A.L.G.O.

    2000-01-01

    Zirconium and titanium phosphates have been used as inorganic ion exchangers for many years. Their characteristics, as high exchange capacity and ionizing and oxidizing reagents resistance, among others, have made them suitable for the treatment of wastes, mostly the radioactive ones. Due to its granulometry, zirconium phosphate (Zr P) must be prepared on an inert support, or it can be synthesized , as well as titanium phosphate, with modifiers, to promote better distribution of the exchanger over the support surface and to enlarge the cavities of their crystal lattice. The prepared exchangers were analyzed by electronic sweep microscopy. The studies on cesium and chromium sorption were made by using radioactive tracer technique, with Cs-134 and Cr-51 radioisotopes. The sorption of cesium in Zr P and Ti P was about 95%, but chromium showed very low sorption in the studied conditions, indicating the necessity of more experiments varying pH and temperature of the solutions. (author)

  16. Interlayer exchange coupling, crystalline and magnetic structure in Fe/CsCl-FeSi multilayers grown by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Dekoster, J.; Degroote, S.; Meersschaut, J.; Moons, R.; Vantomme, A. [K.U. Leuven, Instituut voor Kern- en Stralingsfysica (Belgium); Bottyan, L.; Deak, L.; Szilagyi, E.; Nagy, D.L. [KFKI Research Institute for Particle and Nuclear Physics (Hungary); Baron, A.Q.R. [European Synchrotron Radiation Facility (France); Langouche, G. [K.U. Leuven, Instituut voor Kern- en Stralingsfysica (Belgium)

    1999-09-15

    Crystalline and magnetic structure as well as the interlayer exchange coupling in MBE grown Fe/FeSi multilayers are investigated. From conversion electron Moessbauer spectroscopy and ion beam channeling measurements the spacer FeSi material is found to be stabilized in a crystalline metastable metallic FeSi phase with the CsCl structure. Strong non-oscillatory interlayer exchange coupling is identified with magnetometry and synchrotron Moessbauer reflectometry. From the fits of the time spectrum and the resonant {phi}-{phi} scans a model for the sublayer magnetization of the multilayer is deduced.

  17. Ion exchange currents in vacuum accelerator tubes

    International Nuclear Information System (INIS)

    Eastham, D.A.; Thorn, R.

    1978-01-01

    Ion exchange currents (microdischarges) have been observed in short lengths of accelerator tube. The occurrence of these discharges can be related to the trajectories of ions in the tube. High-resolution mass spectra of the negative and positive ion components have been obtained. (author)

  18. Chemical uranium enrichment with ion exchanger

    International Nuclear Information System (INIS)

    Takeda, Kunihiko; Onitsuka, Hatsuki; Obanawa, Heiichiro

    1991-01-01

    The uranium enrichment by using ion-exchange has been studied and developed since 1972. The ion-exchange rate has been improved approx. 3000 times and the electron exchange reaction, which occurs with ion-exchange reaction, was also accelerated with catalyst. Flow disturbance in a ion-exchange column has been fully studied and the value of turbulence has been reduced to 150μm. These results allowed us to design a very fine separation column, in which about 10000 stages can be obtained even when the column is more than 1 m in diameter. In the course of the development, a self-regenerating reaction between the redox agents was discovered and incorporated into the process, and has resulted in a reduction of 70 % in the separation energy requirement. (author)

  19. Biodegradation of ion-exchange media

    International Nuclear Information System (INIS)

    Bowerman, B.S.; Clinton, J.H.; Cowdery, S.R.

    1988-08-01

    Ion-exchange media, both bead resins and powdered filter media, are used in nuclear power plants to remove radioactivity from process water prior to reuse or environmental discharge. Since the ion- exchange media are made from synthetic hydrocarbon-based polymers, they may be susceptible to damage from biological activity. The purpose of this study was to investigate some of the more basic aspects of biodegradation of ion-exchange media, specifically to evaluate the ability of microorganisms to utilize the ion-exchange media or materials sorbed on them as a food source. The ASTM-G22 test, alone and combined with the Bartha Pramer respirometric method, failed to indicate the biodegradability of the ion-exchange media. The limitation of these methods was that they used a single test organism. In later phases of this study, a mixed microbial culture was grown from resin waste samples obtained from the BNL High Flux Beam Reactor. These microorganisms were used to evaluate the susceptibility of different types of ion-exchange media to biological attack. Qualitative assessments of biodegradability were based on visual observations of culture growths. Greater susceptibility was associated with increased turbidity in solution indicative of bacterial growth, and more luxuriant fungal mycelial growth in solution or directly on the ion-exchange resin beads. 21 refs., 9 figs., 18 tabs

  20. Anisotropy in diffusion and activation energies of I- and CS+ ions in compacted smectite

    International Nuclear Information System (INIS)

    Haruo Sato

    2005-01-01

    The anisotropies and the effect of salinity in the apparent diffusivities (D a ) and activation energies (ΔE a ) of I - and Cs + in compacted Na-smectite were studied. The diffusion experiments in the parallel and perpendicular directions to the orientated direction of smectite particles were performed as a function of smectite's dry density (0.9-1.4 Mg/m 3 ), salinity ([NaCl]=0.01, 0.51 M) and temperature (295-333 K). The Da-values for both ions tended to be higher in the parallel direction than in the perpendicular direction to the orientated direction of smectite particles. The Da-values of I - in the parallel direction decreased with increasing salinity only at low-dry density, but those of Cs + increased with increasing salinity in all conditions. Considering electrostatic effect from the surface of smectite aggregates and the change in tortuosity on dry density, salinity and diffusion direction, I - is interpreted to mainly diffuse in interstitial pores. While, Cs + can diffuse in both interlayer and interstitial pores, and the Da-values of Cs + are presumed to have elevated by the decrease in retardation by competition with Na + . The ΔE a -values of I - , similar levels (ΔE a =15.1-16.1 kJ/mol) to that of the ionic diffusivity in free water (Do) for I - (ΔE a =17.36 kJ/mol) at low-dry density, increased with increasing dry density. On the contrary, the ΔE a -values of Cs + , clearly higher (ΔE a =23.7-25.7 kJ/mol) than that of the Do for Cs + (ΔE a =16.47 kJ/mol) even at low-dry density, increased with increasing dry density. Such high ΔE a -values for Cs + can be explained by considering the ion exchange enthalpy between Cs + and Na + in smectite (ΔH 0 = -11.1 kJ/mol) at low-dry density, and are considered to be due to the effects of the decrease in the activity of porewater and ΔH 0 at high-dry density. (authors)

  1. Ion exchange of strontium on synthetic hydroxyapatite

    International Nuclear Information System (INIS)

    Lazic, S.; Vukovic, Z.

    1991-01-01

    Adsorption of strontium ions on synthetic hydroxyapatite was examined using both batch and column methods. The apatite was prepared from aqueous solutions and characterized by standard analytical methods. The sample obtained had characteristics of well crystallized stoichiometric hydroxyapatite. The experimental data for sorption of strontium can be very well fitted with Langmuir's adsorption isotherm. It was found that sorption occurs by an ion exchange reaction between strontium ions in solution and calcium ions in apatite. (author) 14 refs.; 5 figs.; 1 tab

  2. Studies on the ion-exchange behavior of chromium ferrocyanide

    Energy Technology Data Exchange (ETDEWEB)

    Malik, W U; Srivastava, S K; Singh, Raj Pal; Kumar, Satish [Roorkee Univ. (India). Dept. of Chemistry

    1977-01-01

    The sorption of univalent, bivalent and trivalent ions has been studied on chromium ferrocyanide gel. The distribution of various metal cations were determined by shaking the exchanger (0.1 g) and 20 ml of 0.005M metal ion solution of pH 2-3, until equilibrium was attained. The concentration of Pb/sup 2 +/, Cu/sup 2 +/, Mn/sup 2 +/, Ni/sup 2 +/, Mg/sup 2 +/ and Al/sup 3 +/ were determined by EDTA, ZrO/sup 2 +/, Th/sup 4 +/, UO/sup 2 +/ and Fe/sup 2 +/ were estimated spectrophotometrically and radiometric methods were used for Rb/sup +/, Cs/sup +/, Tl/sup +/, Ag/sup +/, Zn/sup 2 +/, Co/sup 2 +/, Cd/sup 2 +/, Hg/sup 2 +/ and Fe/sup 3 +/ metal ions. The distribution coefficients of various univalent, bivalent and trivalent metal ions (0.002M) were also determined as a function of NH/sub 4/NO/sub 3/ and HNO/sub 3/ concentrations and pH. The studies reveal a high sorption capacity for Cs/sup +/, Tl/sup +/, Ag/sup +/, Cu/sup 2 +/, Zn/sup 2 +/, Cd/sup 2 +/, Fe/sup 3 +/ and Th/sup 4 +/. The sorption of monovalent cations show purely ion exchange mechanism while the uptake of bivalent and trivalent cations is non-equivalent in nature. Single elution of Rb/sup +/, Cs/sup +/ and Tl/sup +/ has been performed from the columns of this exchanger and the recovery is almost complete in all the cases. Cu/sup 2 +/ and Ag/sup +/ get completely adsorbed on the gel column and their elution is not possible probably due to the formation of some new solid phases. Depending on the Ksub(d) values of the metal ions, a large number of separations of radiochemical as well as analytical importance can be performed on the columns of this exchanger material. It is apparent from the Ksub(d) values that a number of separations as Hg/sup 2 +/ from Mg/sup 2 +/, Ca/sup 2 +/ and Pb/sup 2 +/; Mg/sup 2 +/ from Mn/sup 2 +/: Fe/sup 3 +/ from Al/sup 3 +/; and Th/sup 4 +/ from ZrO/sup 2 +/ can be performed on the columns of this exchanger.

  3. ION EXCHANGE IN GLASS-CERAMICS

    Directory of Open Access Journals (Sweden)

    George Halsey Beall

    2016-08-01

    Full Text Available In the past few years ion-exchange in glasses has found a renewed interest with a lot of new development and research in industrial and academic labs and the commercialization of materials with outstanding mechanical properties. These glasses are now widely used in many electronic devices including hand-held displays and tablets. The exchange is generally conducted in a bath of molten salt below the transition temperature of the glass. The exchange at the surface of an alkali ion by a bigger one brings compressive stress at the surface. The mechanical properties are dependent on the stress level at the surface and the depth of penetration of the bigger ion. As compared to glasses, glass-ceramics have the interest to display a wide range of aspects (transparent to opaque and different mechanical properties (especially higher modulus and toughness. There has been little research on ion-exchange in glass-ceramics. In these materials the mechanisms are much more complex than in glasses because of their polyphasic nature: ion-exchange generally takes place mostly in one phase (crystalline phase or residual glass. The mechanism can be similar to what is observed in glasses with the replacement of an ion by another in the structure. But in some cases this ion-exchange leads to microstructural modifications (for example amorphisation or phase change.This article reviews these ion-exchange mechanisms using several transparent and opaque alumino-silicate glass-ceramics as examples. The effect of the ion exchange in the various glass-ceramics will be described, with particular emphasis on flexural strength.

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

    International Nuclear Information System (INIS)

    Lilga, M.A.; Orth, R.J.; Sukamto, J.P.H.

    1997-09-01

    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 10 4 , 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

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

    International Nuclear Information System (INIS)

    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

  6. 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.

  7. Advanced integrated solvent extraction and ion exchange systems

    International Nuclear Information System (INIS)

    Horwitz, P.

    1996-01-01

    Advanced integrated solvent extraction (SX) and ion exchange (IX) systems are a series of novel SX and IX processes that extract and recover uranium and transuranics (TRUs) (neptunium, plutonium, americium) and fission products 90 Sr, 99 Tc, and 137 Cs from acidic high-level liquid waste and that sorb and recover 90 Sr, 99 Tc, and 137 Cs from alkaline supernatant high-level waste. Each system is based on the use of new selective liquid extractants or chromatographic materials. The purpose of the integrated SX and IX processes is to minimize the quantity of waste that must be vitrified and buried in a deep geologic repository by producing raffinates (from SX) and effluent streams (from IX) that will meet the specifications of Class A low-level waste

  8. KOP ion exchange plant officially opened

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The KOP ion exchange plant, which was officially opened in February 1982, can be seen as an important milestone in the history of Klipfontein Organic Products. The plant, erected at a cost of R7 million, has enabled South Africa to achieve virtual self-sufficiency as far as resins are concerned. It will produce R5 million worth of resins per annum, and it has been estimated that it will save the country R3 million per annum in foreign exchange. The plant is the only of its kind in Africa, and will be able to meet 98% of the ion exchange resin requirements of the Republic

  9. Method of solidifying radioactive ion exchange resin

    International Nuclear Information System (INIS)

    Minami, Yuji; Tomita, Toshihide

    1989-01-01

    Spent anion exchange resin formed in nuclear power plants, etc. generally catch only a portion of anions in view of the ion exchange resins capacity and most of the anions are sent while possessing activities to radioactive waste processing systems. Then, the anion exchange resins increase the specific gravity by the capture of the anions. Accordingly, anions are caused to be captured on the anion exchange resin wastes such that the specific gravity of the anion exchange resin wastes is greater than that of the thermosetting resins to be mixed. This enables satisfactory mixing with the thermosetting resins and, in addition, enables to form integral solidification products in which anion exchange resins and cation exchange resins are not locallized separately and which are homogenous and free from cracks. (T.M.)

  10. Leach testing of simulated ion-exchange resin waste solidified in cement

    International Nuclear Information System (INIS)

    Muurinen, A.K.; Uotila, P.I.; Ovaskainen, R.M.

    Leach tests were carried out on ion-exchange resins solidified in cement. Three product mixtures, two isotopes and four leachants at two temperatures, were tested. The increase of resin content increased the leaching of Cs-137; the effect of silix admixture was negligible. The type of the leachant has a stronger influence on Co-60 than on Cs-137. The increase of temperature usually also increased leaching. (author)

  11. Design of Ion-Exchange Resins Through EDTA and DTPA Modified Ligands

    Directory of Open Access Journals (Sweden)

    2014-07-01

    Catechol, resorcinol, and their admixtures with EDTA and DTPA moieties were converted into polymeric resins by alkaline polycondensation with formaldehyde. The resins were characterized by FTIR spectroscopy, elemental analysis, ion-exchange capacity, and distribution coefficient (D for heavy metal and radionuclide such as Cs and Sr. 137Cs and 90Sr constitutes a major source of heat in nuclear waste streams and in regards to recent nuclear event their remediation in complex solution – sea water - represent an important issue.

  12. Detection of gold cluster ions by ion-to-ion conversion using a CsI-converter

    International Nuclear Information System (INIS)

    Nguyen, V.-T.; Novilkov, A.C.; Obnorskii, V.V.

    1997-01-01

    Gold cluster ions in the m/z range of 10 4 -2 x 10 6 u were produced by bombarding a thin film of gold with 252 Cf-fission fragments. The gold covering a C-Al substrate formed islets having a mean diameter of 44 A. Their size- and mass-distribution was determined by means of electron microscopy. The main task was to measure the m/z distribution of the cluster ions ejected from the sample surface. For this purpose we built a time-of-flight (TOF) mass spectrometer, which could be used as a linear TOF instrument or, alternatively, as a tandem-TOF instrument being equipped with an ion-to-ion converter. Combining the results obtained in both modes, it turned out that the linear TOF instrument equipped with micro-channel plates had a mean detection efficiency for 20 keV cluster ions of about 40%. In the tandem mode, the cluster ions hit a CsI converter with energies of 40z keV (z = charge state), from where secondary ions - mainly Cs + and (CsI) n Cs + cluster ions - were ejected. These ions were used to measure the TOF spectrum of the gold cluster ions. The detection efficiency of the cluster ions was found to vary in the available mass range from 99.7% to 96.5%. The complete mass distribution between 4 x 10 4 and 4 x 10 6 u was determined and compared with the corresponding mass distribution of the gold islets covering the substrate. (orig.)

  13. Cation immobilization in pyrolyzed simulated spent ion exchange resins

    International Nuclear Information System (INIS)

    Luca, Vittorio; Bianchi, Hugo L.; Manzini, Alberto C.

    2012-01-01

    Significant quantities of spent ion exchange resins that are contaminated by an assortment of radioactive elements are produced by the nuclear industry each year. The baseline technology for the conditioning of these spent resins is encapsulation in ordinary Portland cement which has various shortcomings none the least of which is the relatively low loading of resin in the cement and the poor immobilization of highly mobile elements such as cesium. The present study was conducted with cationic resin samples (Lewatit S100) loaded with Cs + , Sr 2+ , Co 2+ , Ni 2+ in roughly equimolar proportions at levels at or below 30% of the total cation exchange capacity. Low temperature thermal treatment of the resins was conducted in inert (Ar), or reducing (CH 4 ) gas atmospheres, or supercritical ethanol to convert the hydrated polymeric resin beads into carbonaceous materials that contained no water. This pyrolytic treatment resulted in at least a 50% volume reduction to give mechanically robust spherical materials. Scanning electron microscope investigations of cross-sections of the beads combined with energy dispersive analysis showed that initially all elements were uniformly distributed through the resin matrix but that at higher temperatures the distribution of Cs became inhomogeneous. Although Cs was found in the entire cross-section, a significant proportion of the Cs occurred within internal rings while a proportion migrated toward the outer surfaces to form a crustal deposit. Leaching experiments conducted in water at 25 °C showed that the divalent contaminant elements were very difficult to leach from the beads heated in inert atmospheres in the range 200–600 °C. Cumulative fractional loses of the order of 0.001 were observed for these divalent elements for temperatures below 500 °C. Regardless of the processing temperature, the cumulative fractional loss of Cs in water at 25 °C reached a plateau or steady-state within the first 24 h increasing only

  14. Method of processing spent ion exchange resins

    International Nuclear Information System (INIS)

    Mori, Kazuhide; Tamada, Shin; Kikuchi, Makoto; Matsuda, Masami; Aoyama, Yoshiyuki.

    1985-01-01

    Purpose: To decrease the amount of radioactive spent ion exchange resins generated from nuclear power plants, etc and process them into stable inorganic compounds through heat decomposition. Method: Spent ion exchange resins are heat-decomposed in an inert atmosphere to selectively decompose only ion exchange groups in the preceeding step while high molecular skeltons are completely heat-decomposed in an oxidizing atmosphere in the succeeding step. In this way, gaseous sulfur oxides and nitrogen oxides are generated in the preceeding step, while gaseous carbon dioxide and hydrogen requiring no discharge gas procession are generated in the succeeding step. Accordingly, the amount of discharged gases requiring procession can significantly be reduced, as well as the residues can be converted into stable inorganic compounds. Further, if transition metals are ionically adsorbed as the catalyst to the ion exchange resins, the ion exchange groups are decomposed at 130 - 300 0 C, while the high molecular skeltons are thermally decomposed at 240 - 300 0 C. Thus, the temperature for the heat decomposition can be lowered to prevent the degradation of the reactor materials. (Kawakami, Y.)

  15. Ion exchange behaviour of citrate and EDTA anions on strong and weak base organic ion exchangers

    International Nuclear Information System (INIS)

    Askarieh, M.M.; White, D.A.

    1988-01-01

    The exchange of citrate and EDTA ions with two strong base and two weak base exchangers is considered. Citrate and EDTA analysis for this work was performed using a colorimetric method developed here. The ions most selectively exchanged on the resins are H 2 cit - and H 2 EDTA 2- , though EDTA is generally less strongly sorbed on strong base resins. In contact with weak base resins, deprotonation of the resin occurs during ion exchange with a noticeable drop in solution pH. Although EDTA sorption can be reversed by nitric acid, citrate ions are significantly held on the resin at low pH. The exchange of citrate can be made reversible if bicarbonate is added to the initial solutions. Alkaline regeneration of exchangers loaded with EDTA proved to be very effective. (author)

  16. Ion exchange fiber by radiation grafting, 1

    International Nuclear Information System (INIS)

    Fujiwara, Kunio

    1990-01-01

    Radiation grafting is gaining attention as a method for producing high performance materials. This method can be applied to add functions to existing polymer plastics. The author participated in the research program on the production of ion exchange fiber by radiation grafting and its applicability at the Japan Atomic Energy Research Institute, Takasaki Radiation Chemistry Research Establishment. Consequently, it was clarified that it was possible to introduce the cation exchange group, represented by sulfonic and carboxyl groups, and the anion exchange group, represented by the quarternary ammonium group, to polypropylene fiber available on the market. The ion exchange capacity was able to be controlled by the degree of grafting, i.e. approximately up to 3 meq/g in both strong acid and strong base and approximately up to 5 meq/g in weak acid were obtained. The adsorption performance of ammonia, a representative malodorous substance, was also studied using test cation exchange fiber. The adsorption rate of H type strong acid cation exchange fiber was great, due to the H type having neutral reaction, and the adsorption capacity matched the ion exchange capacity. Although the Cu and Ni types features coordinated adsorption and their adsorption rates were from 1/2 to 1/3 of that of the H type, their adsorption capacities showed increase along with the metal adsorbed. (author)

  17. Applications of inorganic ion exchangers; I-sorption and fixation of some radionuclides in synthetic iron (III)titanate ion exchanger

    International Nuclear Information System (INIS)

    Abou-Mesalam, M.M.; El-Naggar, I.M.

    2002-01-01

    Iron(III) titanate as inorganic ion exchange material has been synthesized by addition of ferric nitrate solution to titanium tetrachloride (dissolved in 4M HCI) with molar ratio equal to unity. The data obtained proposed that the chemical formula of iron(III) titanate may written either as Fe 1 .3 (TiO). 2h 2 O or Fe(TiO 4 ) 0 .76.1.5H 2 O. The surface area values of unloaded and loaded iron(III) titanate with Cs + , Co 2 + and Eu 3 + ions were measured using BET-technique. The selectiy sequence for sorption of Cs + , Co 2 + and Fu 3 + ions on iron (III) titanate was found to be; Co 2 + > Eu 3 + > Cs + . The leach rate values of Cs + , Co 2 + and Fu 3 + ions from iron (II) titanate heated to 1000 degree C different leachants were determined and shows lower values compared to those obtained from unheated iron (III) titanate (dried at 50 degree C) which elucidate the suitability of iron (III) titanate in fixation of Cs + , Co 2 + and Eu 3 + ions by thermal treatment up to1000 degree.

  18. Ion exchange/adsorbent pilot plant

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    A decontamination of greater than 99% of the actinides and fission products contained in radioactive waste water can be obtained using ion exchange resins. A system for achieving this result is described in this paper. This ion exchange pilot-plant design is the culmination of five years of study of the decontamination of radioactive waste streams by ion exchange resins and other adsorbents at Mound. In order to maintain maximum flexibility of treatments, this pilot-plant design is a conceptual design with specific flows, resins, and column specifications, but with many optional features and no rigid equipment specifications. This flexibility allows the system to be amenable to almost any radioactive waste stream. Very specific designs can be constructed from this conceptual design for the treatment of any specific waste stream. Operating and capital costs are also discussed. 1 figure, 5 tables

  19. Modeling of Crystalline Silicotitanate Ion Exchange Columns

    International Nuclear Information System (INIS)

    Walker, D.D.

    1999-01-01

    Non-elutable ion exchange is being considered as a potential replacement for the In-Tank Precipitation process for removing cesium from Savannah River Site (SRS) radioactive waste. Crystalline silicotitanate (CST) particles are the reference ion exchange medium for the process. A major factor in the construction cost of this process is the size of the ion exchange column required to meet product specifications for decontaminated waste. To validate SRS column sizing calculations, SRS subcontracted two reknowned experts in this field to perform similar calculations: Professor R. G. Anthony, Department of Chemical Engineering, Texas A ampersand 038;M University, and Professor S. W. Wang, Department of Chemical Engineering, Purdue University. The appendices of this document contain reports from the two subcontractors. Definition of the design problem came through several meetings and conference calls between the participants and SRS personnel over the past few months. This document summarizes the problem definition and results from the two reports

  20. Leaching studies on ion exchange resins immobilized in bitumen matrix

    International Nuclear Information System (INIS)

    Grosche Filho, C.E.; Chandra, U.; Villalobos, J.P.

    1986-01-01

    Many samples of bitumen mixed with ion exchange resin labelled with 134 Cs were prepared to study radionuclide leaching from bitumen waste forms. The resins used in tests were nuclear grade mixed cationic/aniocic bead resins. Different bitumen types were assayed: two distilled and two oxidized bitumens. Leached fractions were collected accordingly to the recommendation of ISO method, with complete exchange of leachant after each sampling. The volume collected for analysis was one liter. Marinelli beckers were used to improve counting efficiency in a Ge(Li) detector. The diffusion coefficients for samples prepared with distilled and oxidized bitumens were obtained. Mathematical models of transport phenomena applied to cylindrical geometry was employed to fit experimental data aiming to explain leaching mechanism and predict the long time behavior of immobilized radionuclides. (M.C.K.) [pt

  1. environmental studies for removal of some radioactive elements using zirconium silicate as inorganic ion exchange material

    International Nuclear Information System (INIS)

    El-Aryan, Y.F.A.

    2007-01-01

    inorganic ion exchangers have a good potential than the commonly used organic ones for removal and separation of radionuclides from irradiated nuclear fuel solutions. therefore, the main aim of this work is directed to find the optimum conditions for removal of some radionuclides such as Cs + ,Co 2+ ,and Eu 3+ by the prepared zirconium silicate as cation exchanger. the following items will be involved:-1- preparation of zirconium silicate as a cation exchanger. 2- characterization of the prepared exchanger using IR spectra, X-ray diffraction patterns, DTA and TG analyses. 3-chemical stability, capacity and equilibrium measurements will be determined on the materials using at different conditions (heating temperature and reaction temperature). 4- ion exchange isotherms. 5- breakthrough curves for removal of the investigated metal ions on the prepared exchanger under certain conditions

  2. Incineration of ion-exchange resins

    International Nuclear Information System (INIS)

    Valkiainen, M.; Nykyri, M.

    1985-01-01

    Incineration of ion-exchange resins in a fluidized bed was studied on a pilot plant scale at the Technical Research Centre of Finland. Both granular and powdered resins were incinerated in dry and slurry form. Different bed materials were used in order to trap as much cesium and cobalt (inactive tracers) as possible in the bed. Also the sintering of the bed materials was studied in the presence of sodium. When immobilized with cement the volume of ash-concrete is 4 to 22% of the concrete of equal compressive strength acquired by direct solidification. Two examples of multi-purpose equipment capable of incinerating ion-exchange resins are presented. (orig.)

  3. Commercial Ion Exchange Resin Vitrification Studies

    International Nuclear Information System (INIS)

    Cicero-Herman, C.A

    2002-01-01

    In the nuclear industry, ion exchange resins are used for purification of aqueous streams. The major contaminants of the resins are usually the radioactive materials that are removed from the aqueous streams. The use of the ion exchange resins creates a waste stream that can be very high in both organic and radioactive constituents. Therefore, disposal of the spent resin often becomes an economic problem because of the large volumes of resin produced and the relatively few technologies that are capable of economically stabilizing this waste. Vitrification of this waste stream presents a reasonable disposal alternative because of its inherent destruction capabilities, the volume reductions obtainable, and the durable product that it produces

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

    International Nuclear Information System (INIS)

    Lilga, M.A.; Orth, R.J.; Sukamto, J.P.H.; Schwartz, D.T.; Haight, S.M.; Genders, D.

    1996-12-01

    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

  5. Calmodulin-lanthanide ion exchange kinetics

    International Nuclear Information System (INIS)

    Buccigross, J.; O'Donnell, C.; Nelson, D.

    1985-01-01

    A flow dialysis apparatus suitable for the study of high affinity metal binding proteins has been utilized to study calmodulin-metal exchange kinetics. Calmodulin labeled with Eu-155 and Gd-153 was dialyzed against buffer containing various competing metal ions. The rate of metal exchange was monitored by a gamma-ray scintillation detector. The kinetics of exchange are first order, and the rates fall into two categories: Ca (II) and CD (II) in one, and the lanthanides Eu (III), Gd (III), and La (III) in the other

  6. Modeling ion exchange in clinoptilolite using the EQ3/6 geochemical modeling code

    International Nuclear Information System (INIS)

    Viani, B.E.; Bruton, C.J.

    1992-06-01

    Assessing the suitability of Yucca Mtn., NV as a potential repository for high-level nuclear waste requires the means to simulate ion-exchange behavior of zeolites. Vanselow and Gapon convention cation-exchange models have been added to geochemical modeling codes EQ3NR/EQ6, allowing exchange to be modeled for up to three exchangers or a single exchanger with three independent sites. Solid-solution models that are numerically equivalent to the ion-exchange models were derived and also implemented in the code. The Gapon model is inconsistent with experimental adsorption isotherms of trace components in clinoptilolite. A one-site Vanselow model can describe adsorption of Cs or Sr on clinoptilolite, but a two-site Vanselow exchange model is necessary to describe K contents of natural clinoptilolites

  7. Thermochemical treatment of spent ion exchange resins

    International Nuclear Information System (INIS)

    Ojovan, M.I.; Petrov, G.A.; Dmitriev, S.A.; Trusov, B.G.; Semenov, K.N.; Klimov, V.L.

    2001-01-01

    Spent ion exchange resins (IER) is a principal type of radioactive waste constantly generated by nuclear plants of various functions. The reduction of volume of this waste and its treatment to the forms suitable for long-term disposal is an urgent problem facing the present-day atomic energetics. Nowadays the technological process THOR (Studsvik, Sweden) based on the thermodestruction of IER is the best developed and realized on the industrial scale. Unfortunately, this process requires expensive equipment and great energy consumption for the moisture to be evaporated and thereafter IER to be destroyed by heat. Meanwhile the capability of some elements (Mg, Al, Si, Ti etc.) has long been known and practical use found for active interaction with water in combustion regime. This property of the metals has been used in the development of new technology of treatment of IERs in SIA ''Radon''. Wet IER is mixed with powder metal fuel (PMF) which represents a mixture of metal powder, a quantity of burning activator and some technological additives. On initiation, the mixture of IER with PMF burns without extra energy supply to generate enough heat for the moisture to be evaporated and products of IER decomposition to be destroyed and evaporated. To burn out the products of IER evaporation the air is used. The thermodynamic simulation data and the results of experiments using a pilot plant show that radionuclides contained in IER are chemically bound in ash residue consisting of metal oxides, spinel, silicates, etc. According to the experimental data, radionuclides in amounts of 90% or more of Cs-137 and up to 95% of Sr-90 and Co-60 are fixed in the ash residue. The residue volume is several times less than the initial volume of IER. Concentrations of hazard gases in off-gases do not exceed maximum permissible ones accepted in different countries. The technological process is easy to perform, it does not require sophisticated equipment and great energy consumption which

  8. Radiation effects on ion exchange materials

    International Nuclear Information System (INIS)

    Gangwer, T.E.; Goldstein, M.; Pillay, K.K.S.

    1977-11-01

    An extensive literature review and data compilation has been completed on the radiation-damage of ion exchange resins. The primary goal of the study has been to review the available literature on ion exchange materials used in, as well as those with potential for use in, the nuclear fuel and waste reprocessing areas. The physical and chemical properties of ion exchangers are reviewed. Experimental parameters useful in characterizing the effects of radiation on synthetic ion exchange resins are identified or defined. In compiling the diverse types of data, an effort was made to present the experimental data or experimentally based parameters in a format that would be useful for inter-comparing radiation effects on resins. When subject to radiation there are various general trends or qualitative effects displayed by the different types of resins. These radiation-trends and effects have been formulated into qualitative statements. The present day level of understanding of the behavior of resins under ionizing radiation is too limited to justify quantitative predictive modeling. The limitations and deficiencies of the literature are discussed and the experimentation needed to achieve quantitative modeling are outlined. 14 figs., 108 references

  9. Radiation effects on ion exchange materials

    Energy Technology Data Exchange (ETDEWEB)

    Gangwer, T.E.; Goldstein, M.; Pillay, K.K.S.

    1977-11-01

    An extensive literature review and data compilation has been completed on the radiation-damage of ion exchange resins. The primary goal of the study has been to review the available literature on ion exchange materials used in, as well as those with potential for use in, the nuclear fuel and waste reprocessing areas. The physical and chemical properties of ion exchangers are reviewed. Experimental parameters useful in characterizing the effects of radiation on synthetic ion exchange resins are identified or defined. In compiling the diverse types of data, an effort was made to present the experimental data or experimentally based parameters in a format that would be useful for inter-comparing radiation effects on resins. When subject to radiation there are various general trends or qualitative effects displayed by the different types of resins. These radiation-trends and effects have been formulated into qualitative statements. The present day level of understanding of the behavior of resins under ionizing radiation is too limited to justify quantitative predictive modeling. The limitations and deficiencies of the literature are discussed and the experimentation needed to achieve quantitative modeling are outlined. 14 figs., 108 references.

  10. Charge exchange in ion-atom collisions

    International Nuclear Information System (INIS)

    Bransden, B.H.

    1990-01-01

    Charge exchange reactions in which electrons are transferred from one ion (or atom) to another during a collision have been studied both as interesting examples of rearrangement collisions and because of important applications in plasma physics. This article reviews the modern theory developed for use at non-relativistic energies, but excluding the thermal and very low energy region. (author)

  11. Thermal Analysis of LANL Ion Exchange Column

    International Nuclear Information System (INIS)

    Laurinat, J.E.

    1999-01-01

    This document reports results from an ion exchange column heat transfer analysis requested by Los Alamos National Laboratory (LANL). The object of the analysis is to demonstrate that the decay heat from the Pu-238 will not cause resin bed temperatures to increase to a level where the resin significantly degrades

  12. Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin

    International Nuclear Information System (INIS)

    Hubler, T.L.; Franz, J.A.; Shaw, W.J.; Bryan, S.A.; Hallen, R.T.; Brown, G.N.; Bray, L.A.; Linehan, J.C.

    1995-08-01

    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

  13. Synthesis, structural characterization, and performance evaluation of resorcinol-formaldehyde (R-F) ion-exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Hubler, T.L.; Franz, J.A.; Shaw, W.J.; Bryan, S.A.; Hallen, R.T.; Brown, G.N.; Bray, L.A.; Linehan, J.C.

    1995-08-01

    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. Incineration of spent ion exchange resin

    International Nuclear Information System (INIS)

    Hasegawa, Chiaki

    1990-01-01

    It is a pressing need to reduce radioactive waste which is generated from the maintenance and operation of a nuclear power plant. Incineration of low level combustible solid waste such as polyethylene seats, paper and others have been successfully performed since 1984 at the Shimane Nuclear Power Station. Furthermore, for extending incineration treatment to spent ion exchange resin, the incineration test was carried out in 1989. However, as the cation exchange resin contains sulfur and then incineration generates SOx gases, so the components of this facility will be in a corrosive environment. We surveyed incineration conditions to improve the corrosive environment at the exhaust gas treatment system. This paper includes these test results and improved method to incinerate spent ion exchange resin. (author)

  15. Design of zeolite ion-exchange columns for wastewater treatment

    International Nuclear Information System (INIS)

    Robinson, S.M.; Arnold, W.D.; Byers, C.H.

    1991-01-01

    Oak Ridge National Laboratory plans to use chabazite zeolites for decontamination of wastewater containing parts-per-billion levels of 90 Sr and 137 Cs. Treatability studies indicate that such zeolites can remove trace amounts of 90 Sr and 137 Cs from wastewater containing high concentrations of calcium and magnesium. These studies who that zeolite system efficiency is dependent on column design and operating conditions. Previous results with bench-scale, pilot-scale, and near-full-scale columns indicate that optimized design of full-scale columns could reduce the volume of spent solids generation by one-half. The data indicate that shortcut scale-up methods cannot be used to design columns to minimize secondary waste generation. Since the secondary waste generation rate is a primary influence on process cost effectiveness, a predictive mathematical model for column design is being developed. Equilibrium models and mass-transfer mechanisms are being experimentally determined for isothermal multicomponent ion exchange (Ca, Mg, Na, Cs, and Sr). Mathematical models of these data to determine the breakthrough curves for different column configurations and operating conditions will be used to optimize the final design of full-scale treatment plant. 32 refs., 6 figs., 3 tabs

  16. Immobilisation of ion exchange resins in cement

    International Nuclear Information System (INIS)

    Howard, C.G.; Jolliffe, C.B.; Lee, D.J.

    1990-02-01

    Over the last seven years, Low Oxidation State Metal Ion reagents (LOMI) have been used to decontaminate the 100 MW(e) Steam Generating Heavy Water Ractor (SGHWR) at Winfrith. The use of these reagents has resulted in a dilute ionic solution containing activation products which are produced by corrosion of metallic components in the reactor. It has been demonstrated that the amount of activity in the solution can be reduced using organic ion exchanger resins. These resins consist of a cross linked polystyrene with sulphonic acid or quaternary ammonium function groups and can be successfully immobilised in blended cement systems. The formulation which has been developed is produced from a 9 to 1 blend of ground granulated blast furnace slag (BFS) and ordinary Portland cement (OPC) containing 28% ion exchange resin in the water saturated form. If 6% Microsilica is added to the blended cement the waste loading can be increased to 36 w/o. (author)

  17. Ion exchange for treatment of industrial effluents

    International Nuclear Information System (INIS)

    Moreno Daudinot, Aurora Maria; Ge Leyva, Midalis

    2016-01-01

    The acid leaching and ammoniacal carbonate technologies of laterite respectively, are responsible for the low quality of life of the local population, the big deforested areas due to the mining tilling, the elevated contents of solids in the air and waters, as well as the chemical contamination by metals presence, the acidity or basicity of the effluents of both industries, that arrive through the river and the bay to aquifer's mantle. The ion exchange resins allow ions separation contained in low concentrations in the solutions, where the separation of these elements for solvents, extraction or another chemical methods would be costly. Technological variants are proposed in order to reduce the impact produced on the flora and the fauna, by the liquid effluents of nickel industry, by means of ion exchange resins introduction as well as the recuperation of metals and their re incorporation to the productive process. (Author)

  18. Rapid ion-exchange separations of actinides

    International Nuclear Information System (INIS)

    Usuda, Shigekazu

    1988-01-01

    For the purpose of studying short-lived actinide nuclides, three methods for rapid ion exchange separation of actinide elements with mineral acid-alcohol mixed media were developed: anion exchange with nitric acid-methyl alcohol mixed media to separate the transplutonium and rare earth elements from target material, U or Pu and Al catcher foils; anion exchange with hydrochloric acid-methyl alcohol media to separate Am+Cm, Bk and Cf+Fm from the target, catcher foils and major fission products; and cation exchange with hydrochloric acid-methyl alcohol media and with concentrated hydrochloric acid to separate the transplutonium elements as a group from the rare earths after eliminating the large amounts of U, Al, Cu, Fe etc. The methods enable one to perform rapid and effective separation at elevated temperature (90 deg C) and immediate source preparation for alpha-ray spectrometry. (author) 47 refs.; 10 figs

  19. The effect of NO3- and OH- ions on the laser ablation of Cs+ ion on Type 304 stainless steel

    International Nuclear Information System (INIS)

    Hui-Jun Won; Jei-Kwon Moon; Chong-Hun Jung; Kune-Woo Lee; Jae-Hyuk Hyun

    2011-01-01

    Type 304 stainless steel specimens artificially contaminated with CsCl solution were treated with KOH solution and KNO 3 solution, respectively. Cs + ion removal tests by a Q-switched Nd:YAG laser at 1064 nm at a given fluence of 57.3 J/cm 2 were performed. The surface morphology and the relative atomic mole ratio of the specimen surface were investigated by SEM and EPMA. The order of Cs + ion removal efficiency of laser was no-treatment 3 during the 42 shots. From the investigation of XPS peaks around 532.7 and 292.9 eV, KNO 3 on a surface of specimen was found to be fully decomposed during the laser irradiation. It was suggested that Cs 2 O particulates formed by the reaction between the reactive oxygen generated from the nitrate ion and Cs + ion on the metal surface could be easily suspended. For the KOH system, FeOOH was formed during the laser irradiation and it changed into Fe 2 O 3 . It was also suggested that Cs 2 O particulates were formed by the reaction between the reactive oxygen generated from the decomposition of K 2 O and Cs + ion on the metal surface. (author)

  20. High Br- Content CsPb(Cl yBr1- y)3 Perovskite Nanocrystals with Strong Mn2+ Emission through Diverse Cation/Anion Exchange Engineering.

    Science.gov (United States)

    Li, Fei; Xia, Zhiguo; Pan, Caofeng; Gong, Yue; Gu, Lin; Liu, Quanlin; Zhang, Jin Z

    2018-04-11

    The unification of tunable band edge (BE) emission and strong Mn 2+ doping luminescence in all-inorganic cesium lead halide perovskite nanocrystals (NCs) CsPbX 3 (X = Cl and Br) is of fundamental importance in fine tuning their optical properties. Herein, we demonstrate that benefiting from the differentiation of the cation/anion exchange rate, ZnBr 2 and preformed CsPb 1- x Cl 3 : xMn 2+ NCs can be used to obtain high Br - content Cs(Pb 1- x- z Zn z )(Cl y Br 1- y ) 3 : xMn 2+ perovskite NCs with strong Mn 2+ emission, and the Mn 2+ substitution ratio can reach about 22%. More specifically, the fast anion exchange could be realized by the soluble halide precursors, leading to anion exchange within a few seconds as observed from the strong BE emission evolution, whereas the cation exchange instead generally required at least a few hours; moreover, their exchange mechanism and dynamics process have been evaluated. The Mn 2+ emission intensity could be further varied by controlling the replacement of Mn 2+ by Zn 2+ with prolonged ion exchange reaction time. White light emission of the doped perovskite NCs via this cation/anion synergistic exchange strategy has been realized, which was also successfully demonstrated in a prototype white light-emitting diode (LED) device based on a commercially available 365 nm LED chip.

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

    International Nuclear Information System (INIS)

    Kumar, A.; Varshney, L.

    2010-01-01

    137 Cs (t 1/2 = 30 years) is one of the major radioisotope present in high level liquid waste (HLLW) generated during the reprocessing of nuclear fuel. Separation of 137 Cs from HLLW results in reduction of personal radiation exposure during the conditioning, transportation, storage and disposal. In addition, 137 Cs 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

  2. Study of the Fixation and Migration of Radioactive Cations in a Natural Ion-Exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Baetsle, L. [Centre d' Etudes de l' Energie Nucleaire, Mol (Belgium)

    1960-07-01

    The purpose of this study is to analyse the behaviour of Sr90 and Cs137 on natural ion-exchangers such as lignite and soil. Lignite is a substance which is found in large quantities near the Belgian Nuclear Energy Research Centre (CEN) at Mol and is particularly useful in the processing of radioactive liquid wastes because of its ion-exchange properties. The physical and chemical characteristics of lignite which have a bearing on ion exchange are given in section 1 of this paper. The various ion equilibria which affect the processing of.radioactive liquid wastes are studied in section 2, which also lists the basic factors required for calculating the rate of saturation of a lignite column. The speed of ion migration in the soil is studied along the same lines as for lignite.

  3. An Empirical Formula From Ion Exchange Chromatography and Colorimetry.

    Science.gov (United States)

    Johnson, Steven D.

    1996-01-01

    Presents a detailed procedure for finding an empirical formula from ion exchange chromatography and colorimetry. Introduces students to more varied techniques including volumetric manipulation, titration, ion-exchange, preparation of a calibration curve, and the use of colorimetry. (JRH)

  4. Poster 29. Modelling of ion exchange processes in ultrapure water

    International Nuclear Information System (INIS)

    Berg, A.; Torstenfelt, B.; Fejes, P.; Foutch, G.L.

    1992-01-01

    The ion exchange process of the Reactor Water Clean-up (RWCU) system has been studied to better use the maximum possible exchange capacity of the ion exchange resin. Laboratory data have been correlated with computer simulations of the ion exchange process. Data were correlated using a mixed-bed ion exchange model for ultralow ionic concentrations developed at Oklahoma State University. Experimental results of the ion exchange column operation in the concentration range of 10 -3 M boric acid is compared with the simulated performance predicted by the computer model. The model is found to agree reasonably well with the data. (author)

  5. Charge exchange with ion excitation: asymptotic theory

    International Nuclear Information System (INIS)

    Ivakin, I.A.; Karbovanets, M.I.; Ostrovskii, V.N.

    1987-01-01

    There is developed an asymptotic (with respect to the large internuclear separation R) theory for computing the matrix element of the exchange interaction between states of quasimolecules, which is responsible for charge transfer with ion excitation: B + +A→B+A + *. A semiclassical approximation is used, which enables one to apply the theory to processes with the participation of multiply charged ions. The case of s--s transitions for excitation of the ion A + →A + *, where it is appropriate to take into account the distortion of the wave functions of the ion A + by the particle B, is treated separately. Calculations of cross sections and comparison with the results of experiments for He + --Cd and Ne + --Mg collisions at thermal energies are given. It is shown that it is impossible to explain the experimental data by the interaction of terms of the quasimolecules at large R only, and a possible mechanism for populating at small R is proposed

  6. 3.5 Radiation stability of ion exchangers

    International Nuclear Information System (INIS)

    Marhol, M.

    1976-01-01

    The main knowledge is summed up of the radiation stability of ion exchangers. No basic changes occur in inorganic ion exchangers with the exception of the exchange capacity at doses of up to 10 9 rad. This also applies to coal-based ion exchangers. Tables are given showing the changes in specific volume, exchange capacity and weight of different types of organic ion exchangers in dependence on the radiation dose. The effects are discussed of the structure of organic cation and anion exchangers, polymeric strong basic anion exchangers, polycondensate anion exchangers and ion exchange membranes on their radiation stability. General experimental procedures are given for laboratory tests of the radiation stability of exchangers. (L.K.)

  7. Porous solid ion exchange wafer for immobilizing biomolecules

    Science.gov (United States)

    Arora, Michelle B.; Hestekin, Jamie A.; Lin, YuPo J.; St. Martin, Edward J.; Snyder, Seth W.

    2007-12-11

    A porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer. Also disclosed is a porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer containing a biomolecule with a tag. A separate bioreactor is also disclosed incorporating the wafer described above.

  8. Charge exchange processes involving iron ions

    International Nuclear Information System (INIS)

    Phaneuf, R.A.

    1985-01-01

    A review and evaluation is given of the experimental data which are available for charge exchange processes involving iron ions and neutral H, H 2 and He. Appropriate scaling laws are presented, and their accuracy estimated for these systems. A bibliography is given of available data sources, as well as of useful data compilations and review articles. A procedure is recommended for providing single approximate formulae to the fusion community to describe total cross sections for electron capture by partially-stripped Fe/sup q+/ ions in collisions with H, H 2 and He, based on the scaling relationships suggested by Janev and Hvelplund

  9. 21 CFR 173.21 - Perfluorinated ion exchange membranes.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Perfluorinated ion exchange membranes. 173.21... ion exchange membranes. Substances identified in paragraph (a) of this section may be safely used as ion exchange membranes intended for use in the treatment of bulk quantities of liquid food under the...

  10. Ion exchange properties of carboxylate bagasse

    International Nuclear Information System (INIS)

    Nada, A.M.A.; Hassan, M.L.

    2005-01-01

    Bagasse fibers were chemically modified using three different reactions: esterification using monochloro acetic acid, esterification using succinic anhydride, and oxidation using sodium periodate and sodium chlorite to prepare cation exchanger bearing carboxylic groups. Bagasse was crosslinked using epichlorohydrin before chemical modification to avoid loss of its constituents during the chemical modification. The structure of the prepared derivatives was proved using Fourier transform infrared (FTIR) and chemical methods. The ability of the prepared bagasse cation exchangers to adsorb heavy metal ions (Cu +2 , Ni +2 , Cr +3 , Fe +3 ), on a separate basis or in a mixture of them, at different metal ion concentration was tested. Thermal stability of the different bagasse derivative was studied using thermogravimetric analysis (TGA)

  11. Ion Exchange Temperature Testing with SRF Resin - 12088

    Energy Technology Data Exchange (ETDEWEB)

    Russell, R.L.; Rinehart, D.E.; Brown, G.N.; Peterson, R.A. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States)

    2012-07-01

    Ion exchange using the Spherical Resorcinol-Formaldehyde (SRF) resin has been selected by the U.S. Department of Energy's Office of River Protection for use in the Pretreatment Facility of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) and for potential application in an at-tank deployment for removing Cs-137. Recent proposed changes to the WTP ion exchange process baseline indicate that higher temperatures (50 deg. C) to alleviate post-filtration precipitation issues prior to reaching the ion exchange columns may be required. Therefore, it is important to understand the behavior of SRF resin performance under the conditions expected with the new equipment and process changes. This research examined the impact of elevated temperature on resin loading and resin degradation during extended solution flow at elevated temperature (45 deg., 50 deg., 55 deg., 60 deg., 65 deg., 75 deg. C). Testing for extended times at elevated temperatures showed that the resin does degrade and loading capacity is reduced at and above 45 deg. C. Above 60 deg. C the resin appears to not load at all. It was observed that the resin disintegrated at 75 deg. C until not much was left and partially disintegrated at 65 deg. C, which caused the column to plug in both tests after ∼336 hours. The results indicate that WTP will lose resin loading capacity if the ion exchange process is performed above 25 deg. C, and the resin will disintegrate above 65 deg. C. Therefore, WTP will have a restricted operating range of temperatures to perform the ion exchange process with this resin. PNNL and WTP are currently evaluating the operating limits of the resin in further detail. Aging in 0.5 M HNO{sub 3} also caused the resin to lose capacity above 25 deg. C and to completely dissolve at 55 deg. C. Again, WTP will have a restricted operating range of temperatures when eluting the resin with nitric acid in order to maintain resin loading capacity and avoid disintegration of the resin

  12. PRTR ion exchange vault water removal

    International Nuclear Information System (INIS)

    Ham, J.E.

    1995-11-01

    This report documents the removal of radiologically contaminated water from the Plutonium Recycle Test Reactor (PRTR) ion exchange vault. Approximately 57,000 liters (15,000 gallons) of water had accumulated in the vault due to the absence of a rain cover. The water was removed and the vault inspected for signs of leakage. No evidence of leakage was found. The removal and disposal of the radiologically contaminated water decreased the risk of environmental contamination

  13. Low-level liquid waste decontamination by inorganic ion exchange

    International Nuclear Information System (INIS)

    Campbell, D.O.; Lee, D.D.; Dillow, T.A.

    1990-01-01

    Improved processes are being developed to treat contaminated liquid wastes that have been and continue to be generated at Oak Ridge National Laboratory. The most serious contaminants are 137 Cs and 90 Sr, and certain inorganic ion-exchange material have given promising results. Nickel and cobalt hexacyanoferrate (II) compounds are extremely selective for cesium removal, with distribution coefficients in excess of 10 6 even in the presence of high cesium and moderate potassium concentrations. Sodium titanate is selective for strontium removal from solutions with high alkali metal concentrations, especially at high pH. These separations are so efficient that one or two stages of simple, batch separation can yield large DFs (∼10 4 ) while still generating small volumes of solid waste

  14. Ion-exchange equilibria and diffusion in engineered backfill

    International Nuclear Information System (INIS)

    Soudek, A.; Jahnke, F.M.; Radke, C.J.

    1984-01-01

    Engineered backfill can add confidence to confinement times of high-level nuclear waste stored in geologic media. This paper discusses the design and operation of a unique radial-flow diffusion cell to determine ion migration rates in backfill material under realistic repository conditions. New experimental results were reported for diffusion of CsCl in a background of NaCl into compacted bentonite and bentonite/quartz mixtures. Representation of the measured diffusion rates by the traditional, homogeneous porous-medium model significantly underestimates cesium penetration distances into the backfill. Surface diffusion is suggested as an additional mechanism by which cations transport in swollen montmorillonite; the surface diffusion coefficients for cesium is determined to be approximately 10 -7 cm 2 /s. An electrostatic site-binding model is developed for ion-exchange equilibria on montmorillonite clay. The effect of pH, ionic strength, and specific adsorption are evaluated and compared favorably to new, experimental exchange isotherms measured on disaggregated clay. The electrostatic site-binding model permits a prediction of the influence of backfill compaction on K/sub d/ values. We find that for strongly adsorbing cations, compactions has little effect. However, anions exhibit significant Donnan exclusion with clay compaction. 40 references, 12 figures

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

    International Nuclear Information System (INIS)

    Brooks, K.P.

    1996-04-01

    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

  16. Vitrification of cesium-contaminated organic ion exchange resin

    International Nuclear Information System (INIS)

    Sargent, T.N. Jr.

    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

  17. Ion exchange flowsheet for recovery of cesium from purex sludge supernatant at B Plant

    International Nuclear Information System (INIS)

    Carlstrom, R.F.

    1977-01-01

    Purex Sludge Supernatant (PSS) contains significant amounts of 137 Cs left after removal of strontium from fission product bearing Purex wastes. To remove cesium from PSS, an Ion Exchange Recovery system has been set up in Cells 17-21 at B Plant. The cesium that is recovered is stored within B Plant for eventual purification through the Cesium Purification process in Cell 38 and eventual encapsulation and storage in a powdered form at the Waste Encapsulation Storage Facility. Cesium depleted waste streams from the Ion Exchange processes are transferred to underground storage

  18. Method of pyrolysis for spent ion-exchange resins

    International Nuclear Information System (INIS)

    Aoyama, Yoshiyuki; Matsuda, Masami; Kawamura, Fumio; Yusa, Hideo.

    1985-01-01

    Purpose: To prevent the generation of noxious sulfur oxide and ammonia on the pyrolysis for spent ion-exchange resins discharged from nuclear power plants. Method: In the case where the pyrolysis is made for the cationic exchange resins having sulfonic acids as the ion-exchange group, alkali metals or alkaline earth metals capable of reacting with sulfonic acid groups to form solid sulfates are previously deposited by way of ion-exchange reactions prior to the pyrolysis. In another case of the anionic exchange resins having quarternary ammonium groups as the ion-exchange groups, halogenic elements capable of reacting with the ammonium groups to form solid ammonium salts are deposited to the ion-exchange resins through ion-exchange reactions prior to the pyrolysis. As a result, the amount of the binders used can be reduced, and this method can be used in a relatively simple processing facility. (Horiuchi, T.)

  19. Method of burning ion-exchange resin contaminated with radioactivity

    International Nuclear Information System (INIS)

    Suzuki, Shigenori.

    1986-01-01

    Purpose: To process spent ion exchange resins to reduce their volume, without increasing the load on a off-gas system and in a stable state and at the same time not leaving any uncombusted portions. Method: The water slurries of the ion exchange resins contaminated with radioactive materials is dehydrated or dry combusted to reduce the water content. A binder is then added to solidify the ion exchange resin. The solidified ion exchange resins are then combusted in a furnace. This prevents the ion exchange resin from being dispersed by air and combustion gases. Furthermore, the solidified ion exchange resins in the form of small pellets burn from the surface inwards. Moreover the binder is carbonized by the combustion heat and promotes combustion to convert the ion exchange resins into a solid mass, making sure that no uncombusted portion is left. (Takahashi, M.)

  20. Novel silica-based ion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    Eichrom`s highly successful Diphonixo resin resembles a conventional ion exchange resin in its use of sulfonic acid ligands on a styrene- divinylbenzene matrix. Diphonix resin exhibits rapid exchange kinetics that allow economical operation of ion exchange systems. Unlike conventional resins, Diphonix resin contains chelating ligands that are diphosphonic acid groups that recognize and remove the targeted metals and reject the more common elements such as sodium, calcium and magnesium. This latter property makes Diphonix ideal for many industrial scale applications, including those involving waste treatment. For treatment of low-level, transuranic (TRU) and high- level radioactive wastes, Diphonix`s polystyrene backbone hinders its application due to radiolytic stability of the carbon-hydrogen bonds and lack of compatibility with expected vitrification schemes. Polystyrene-based Diphonix is approximately 60% carbon- hydrogen. In response to an identified need within the Department of Energy for a resin with the positive attributes of Diphonix that also exhibits greater radiolytic stability and final waste form compatibility, Eichrom has successfully developed a new, silica-based resin version of Diphonix. Target application for this new resin is for use in environmental restoration and waste management situations involving the processing of low-level, transuranic and high-level radioactive wastes. The resin can also be used for processing liquid mixed waste (waste that contains low level radioactivity and hazardous constituents) including mixed wastes contaminated with organic compounds. Silica-based Diphonix is only 10% carbon-hydrogen, with the bulk of the matrix silica.

  1. Microbial treatment of ion exchange resins

    International Nuclear Information System (INIS)

    Kouznetsov, A.; Kniazev, O.

    2001-01-01

    A bioavailability of ion exchange resins to a microbial destruction as one of the alternative methods of compacting used ionites from the nuclear fuel manufacturing cycle enterprises has been investigated. The bio-destruction was studied after a preliminary chemical treatment or without it. A sensitivity of the ion exchange resins (including highly acidic cationite KU-2-8) to the microbial destruction by heterotrophic and chemo-litho-trophic microorganisms under aerobic conditions was shown in principle. The biodegradation of the original polymer is possible in the presence of the water soluble fraction of the resin obtained after its treatment by Fenton reagent and accelerated in the presence of Mn-ions in optimal concentration 1-2 g of Mn per liter of medium. Thus, the process of bio-destruction of ionite polymer by heterotrophic microorganisms can be compared with the bio-destruction of lignin or humic substances. The optimum parameters of bio-destruction and microorganisms used must be different for resins with different functional groups. (authors)

  2. A structural study of nepheline hydrate I, an inorganic ion exchanger

    International Nuclear Information System (INIS)

    Hansen, S.

    1985-01-01

    The crystal structures of nepheline hydrates I, Na 3 Al 3 Si 3 O 12 x 2H 2 O, and three compounds produced by ion exchange with aqueous KCl, RbCl and CsCl at 80 degrees C, have been studied using X-ray diffraction methods. This synthetic silicate has a tetrahedral framework with a two-dimensional pore system consisting of perpendicular 8-ring and 6-ring channels. The long-range ordering of Si and Al into adjacent tetrahedra is well developed. Some aspects of the topology, geometry and bonding of the tetrahedral frame are discussed. Related framework types are derived by unit cell twinning of the idealized cristobalite structure. A limit in the ion exchange is observed when about 1/3 of the Na + ions have been replaced. This behaviour is explained by the restricted volume of two Na sites situated in the 6-ring channel. The readily exchangeable ions and water molecules in the 8-ring channels an arrangement which gradually changes when the size of the alkali metal-ion increases. Most K + -exchanged crystals have a unit cell which is determined by the translational symmetry of the framework, while the original Na form has a two-fold superstructure and the Rb + -exchanged form has a five-fold superstructure. Caesium-ion-exchanged crystals have incommensurate structures. The occurrence of superstructures is related to long-range ordering of the species in the 8-ring channels. (author)

  3. Probing molecules on a surface by Cs+ reactive ion scattering: identification of C2Hx (x≤4) hydrocarbons

    International Nuclear Information System (INIS)

    Kang, H.; Lee, C.W.; Hwang, C.H.; Kim, C.M.

    2003-01-01

    We studied molecular species appearing in the reactions of ethylene on a Pt(1 1 1) surface by the technique of Cs + reactive ion scattering (Cs + RIS). Dehydrogenation reaction of ethylene was examined for a surface temperature range of 100-800 K, and the RIS result verified the well-known sequence of forming di-σ-bonded ethylene (-CH 2 -CH 2 -), ethylidyne (≡C-CH 3 ), CH, and then surface carbons, as the temperature increased. In particular, the intermediate species in the conversion of ethylene to ethylidyne was closely investigated, which showed the presence of an ethylidene intermediate (≡CH-CH 3 ). In a study of H/D exchange reactions between surface C 2 D 4 and H, we successfully identified the ethylenes in which several deuterium atoms were substituted by hydrogen (C 2 D 4-x H x ,x=0-4), and quantitatively determined their relative populations. These examples demonstrate the ability of the Cs + RIS method to identify small hydrocarbons and their isotope-exchanged species on surfaces

  4. Generation of CsI cluster ions for mass calibration in matrix-assisted laser desorption/ionization mass spectrometry

    NARCIS (Netherlands)

    Lou, X.; Dongen, van J.L.J.; Meijer, E.W.

    2010-01-01

    A simple method was developed for the generation of cesium iodide (CsI) cluster ions up to m/z over 20,000 in matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS). Calibration ions in both positive and negative ion modes can readily be generated from a single MALDI spot of CsI(3)

  5. Properties of the Carboxylate ion exchange resins

    International Nuclear Information System (INIS)

    Allard, Bert; Dario, Maarten; Boren, Hans; Torstenfelt, Boerje; Puigdomenech, Ignasi; Johansson, Claes

    2002-09-01

    Weakly acidic, carboxylic resin has been selected, together with strong base anion resins, for water purification at the Forsmark 1 and 2 reactors. For the strong (but not the weak) ion exchange resin the Nuclear Power Inspectorate has given permission to dispose the spent resins in the SFR 1 (the Final Repository for Radioactive Operational Waste). This report gives a review of the carboxylic resins and comes to the conclusion that the resins are very stable and that there should not exist any risks for increased leaching of radionuclides from SFR 1 if these resins are disposed (compared to the strong resins)

  6. Immobilisation of ion exchange resins in cement

    International Nuclear Information System (INIS)

    Howard, C.G.; Jolliffe, C.B.; Lee, D.J.

    1990-09-01

    The removal of activity from spent decontaminating solutions eg LOMI can be achieved using organic ion exchange resins. These resins can be successfully immobilised in cement based matrices. The optimum cement system contained 10% ordinary Portland cement 84% gg blast furnace slag, 6% microsilica with a water cement ratio of 0.5 and a dry resin loading of 36% with respect to total weight. This formulation was successfully scaled up to 200 litres giving a product with acceptable compressive strength, dimensional stability and elastic modulus. Storage of samples under water appears to have no detrimental effects on the product's properties. (author)

  7. Immobilisation of ion exchange resins in cement

    International Nuclear Information System (INIS)

    Howard, C.G.; Jolliffe, C.B.; Lee, D.J.

    1990-09-01

    The removal of activity from spent decontaminating solutions eg LOMI can be achieved using organic ion exchange resins. These resins can be successfully immobilised in cement based matrices. The optimum cement system contained 10% ordinary Portland cement, 84% gg blast furnace slag, 6% microsilica with a water cement ratio of 0.5 and a dry resin loading of 36% with respect to total weight. This formulation was successfully scaled up to 200 litres giving a product with acceptable compressive strength, dimensional stability and elastic modulus. Storage of samples under water appears to have no detrimental effects on the products' properties. (author)

  8. Biodegradation of ion-exchange media

    International Nuclear Information System (INIS)

    Bowerman, B.S.; Clinton, J.H.; Cowdery, S.R.

    1988-01-01

    The purpose of this study was to investigate further the potential for ion-exchange media (resin beads or powdered filter media) to support biological growth. A mixed microbial culture was grown from resin wastes obtained from the BNL HFBR by mixing the resin with a nutrient salt solution containing peptone and yeast extract. Bacterial and fungal growths appeared in the solution and on the resins after 7 to 10 days incubation at 337/degree/C. The mixed microbial cultures were used to inoculate several resin types, both irradiated and unirradiated. 12 refs., 5 tabs

  9. Extraction of Co ions from ion-exchange resin by supercritical carbon dioxide

    International Nuclear Information System (INIS)

    Ju, Min Su; Koh, Moon Sung; Yang, Sung Woo; Park, Kwang Heon; Kim, Hak Won; Kim, Hong Doo

    2005-01-01

    There are a number of liquid treatment processes for eliminating radioactive ionic contaminants in nuclear facilities. One of the most common treatment methods for aqueous streams is the use of ion exchange, which is a well-developed technique that has been employed for many years in the nuclear industry. More specifically speaking, systems that ion exchange method is applied to in nuclear power plants are liquid radioactive waste treatment system, chemical and volume control system, steam generator blowdown treatment system, and service water supply system. During the operation of nuclear power plants, radioactive contaminants such as Co-60, Mn-54, Fe-59 and Cs-137 are contained in liquid radioactive wastes. And the wastes containing small amount of uranium are generated in nuclear fuel cycle facilities. To treat the liquid radioactive waste, we usually install ion exchangers rather than evaporators due to their simplicity and effectiveness, and this trend is increasing. However, the ion exchange process produces large volume of spent organic resin, and has some problems of radiation damage and thermal instability. And the reuse of the resin is limited due to the degradation of ion-exchanging ability. For this reason, were should consider a better method to expand the lifetime of the resin or to reduce the volume of radioactive resin wastes by extracting radioactive contaminants located in the resin. Supercritical fluid CO 2 has many good points as a process solvent that include low viscosity, negligible surface tension, and variable selectivity. And supercritical fluids have physical properties of both liquid and gas such as good penetration with a high dissolution capability. Supercritical fluids have been widely used in extraction, purification, and recovery processes. A number of workers applied supercritical CO 2 solvent for cleaning of precision devices and waste treatments. Since supercritical CO 2 has its mild critical point at 31 and 73.8bar as .deg. C

  10. Anisotropic microporous supports impregnated with polymeric ion-exchange materials

    Science.gov (United States)

    Friesen, Dwayne; Babcock, Walter C.; Tuttle, Mark

    1985-05-07

    Novel ion-exchange media are disclosed, the media comprising polymeric anisotropic microporous supports containing polymeric ion-exchange or ion-complexing materials. The supports are anisotropic, having small exterior pores and larger interior pores, and are preferably in the form of beads, fibers and sheets.

  11. Ion exchanger material based on Titanium phosphate for liquid radioactive waste treatment

    Energy Technology Data Exchange (ETDEWEB)

    Maslova, M.; Gerasimova, L. [Tananaev Institute of Chemistry and Technology of Rare Elements and Mineral Resources, Kola Scientific Center, Russian Academy of Sciences, Apatity (Russian Federation)

    2013-07-01

    A comparative study of the physicochemical and service properties of samples of Ti(OH) 1.36(HPO4) 1.32 * 2.3H2O sorbent in the finely dispersed and granulated forms, mastered for commercial production, was made. The sorption of Cs and Sr cations from solutions of various, compositions was studied in batch experiments, and the diffusion coefficients of the exchanging ions were determined. The hydrolytic stability of the. sorbents was examined with the aim to determine the optimal operation conditions. Experiments showed that the cation exchangers based on titanium phosphate are the most efficient in removal from liquid radioactive waste of induced radioactive isotopes of corrosion products, which is due to formation of weakly dissociating compounds of nonferrous metal ions with functional groups of the ion exchangers in the sorbent phase. (author)

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

    International Nuclear Information System (INIS)

    CHARLES, NASH

    2004-01-01

    The River Protection Project - Hanford Tank Waste Treatment and Immobilization Plant will use cesium ion exchange to remove 137Cs from Low Activity Waste down to 0.3 Ci/m3 in the Immobilized LAW, ILAW product. The 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 the Department of Energy approved equivalent. SL-644 is solely available through IBC Advanced Technologies. To provide an alternative to this sole-source resin supply, the RPP--WTP initiated a three-stage process for selection and qualification of an alternative ion exchange resin for cesium removal in the RPPWTP. It was recommended that resorcinol formaldehyde RF be pursued as a potential alternative to SL-644

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

    International Nuclear Information System (INIS)

    Manosso, Helena Cristina

    2006-01-01

    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

  14. Ion exchange separation of rare earths. I

    International Nuclear Information System (INIS)

    Nghi, Nguyen danh; Matous, K.

    1977-01-01

    The optimal conditions of separating selected rare earths by two ion exchange chromatography using Ostion KS cation exchange resin were studied. The effect of acetic acid concentration in the sorption solution was investigated. The elution process was studied in dependence on the concentration of Na 2 H 2 EDTA, on the total concentration of EDTA 4- ion, on elution agent flow, and on temperature. The optimal conditions were determined by evaluating integral elution curves and changes in acid concentration for systems Y-Pr, La-Pr, Er-Pr, Eu-Pr as follows: The sorption solution requires the presence of Na 2 H 2 EDTA of 0.03M in concentration. The basic elution solution was prepared in the following way: 0.183M Na 2 Mg 2 EDTA, 9.6x10 -3 M Na 2 H 2 EDTA, 3.84x10 -3 M CH 3 COOH, 2.30x10 -2 M CH 3 COONH 4 , 2.30x10 -2 M (NH 4 ) 2 SO 4 . Approximate pH 5.7 to 6.0. The optimal elution solution was prepared by diluting the basic solution so that the total concentration of EDTA 4- equalled 0.075M. The optimal flow was determined to be 0.86 ml.cm -2 .min -1 at a temperature of 55 degC. (author)

  15. Radionuclide Leaching from Organic Ion Exchange Resin

    International Nuclear Information System (INIS)

    Delegard, C.H.; Rinehart, D.E.

    1998-01-01

    Laboratory tests were performed to examine the efficacy of leach treatments for decontaminating organic ion exchange resins (OIER), which have been found in a number of samples retrieved from K East Basin sludge. Based on process records, the OIER found in the K Basins is a mixed-bet strong acid/strong base material marketed as Purolitetrademark NRW-037. Radionuclides sorbed or associated with the OIER can restrict its disposal to the Environmental Restoration Disposal Facility (ERDF). The need for testing to support development of a treatment process for K Basin sludge has been described in Section 4.2 of ''Testing Strategy to Support the Development of K Basins Sludge Treatment Process'' (Flament 1998). To help understand the effects of anticipated OIER elutriation and washing, tests were performed with well-rinsed OIER material from K East Basin floor sludge (sample H-08 BEAD G) and with well-rinsed OIER having approximately 5% added K East canister composite sludge (sample KECOMP). The rinsed resin-bearing material also contained the inorganic ion exchanger Zeolon-900trademark, a zeolite primarily composed of the mineral mordenite. The zeolite was estimated to comprise 27 weight percent of the dry H-08 BEAD G material

  16. Study of the advantage and drawback of using Cs+ primary ion beam on metal targets

    International Nuclear Information System (INIS)

    Vallerand, P.; Baril, M.

    1977-01-01

    The simplicity of the design of the thermoionic primary ion-source renders its use very easy. Four groups of targets were studied: 1) pure metals (Cu, Cd, Al, Mo, Pb, Zn); 2) various phosphor bronzes of certified composition; 3) four different iron and nickel stainless steels; 4) two kinds of Babbitt alloys. The intensity of the positive spectra is much lower than that of the negative ones. But both contain useful complementary information. Combining the use of a leak of oxygen with the bombardment by Cs + ion enables the detection of many elements at a much lower level of concentration. The easiness of cluster production is another characteristic of Cs + bombardment. (Auth.)

  17. Application to ion exchange study of an interferometry method

    International Nuclear Information System (INIS)

    Platzer, R.

    1960-01-01

    The numerous experiments carried out on ion exchange between clay suspensions and solutions have so far been done by studying the equilibrium between the two phases; by this method it is very difficult to obtain the kinetic properties of the exchange reactions. At method consisting of observation with an interferential microscope using polarised white light shows up the variations in concentration which take place during the ion exchange between an ionic solution and a montmorillonite slab as well as between an ionic solution and a grain of organic ion exchanger. By analysing the results it will be possible to compare the exchange constants of organic ion exchangers with those of mineral ion exchangers. (author) [fr

  18. Small-Scale Ion Exchange Removal of Cesium and Technetium from Hanford Tank 241-AN-102

    International Nuclear Information System (INIS)

    Hassan, N.M.

    2000-01-01

    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 and high activity waste glass, respectively. The pretreatment includes sludge washing, filtration, precipitation, and ion exchange processes to remove entrained solids, cesium, transuranics, technetium, and strontium. The cesium (Cs-137) and technetium (Tc-99) ion exchange removal 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 anionic 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 Tech nology Center2 demonstrated the conceptualized flow sheet parameters with an Envelope C sample from Hanford Tank 241-AN-107. Those experiments also 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

  19. Leaching studies on ion exchange resins immobilized in bitument matrix

    International Nuclear Information System (INIS)

    Grosche Filho, C.E.; Chandra, U.; Villalobos, J.P.

    1987-01-01

    To study radionuclide leaching from bitumen waste forms, many samples of bitumen mixed with ion-exchange resin labelled with 134 Cs were prepared. The resins used in the tests were nuclear grade mixed cationic/anionic bead resins. Different bittumen types were assayed: two destilled and to oxidized bitumens. Laboratory to scale samples, with surface/volume ratio (S/V) = 1, were molded to 5 cm diameter and 10 cm height. The composition of the mixtures were: 30, 40, 50 and 60% by weight of dried resin with bitumen. The leachant was deionized water with a leachant volume to sample surface rario of about 8 cm. Leached fractions were collected according to the recommendation of ISO method, with complete exchange of leachant beckers after each sampling. The volume collected for analysis was one liter. Marinelli were used for counting in a Ge(Li) detector. Up to now, results of 250 days have been accumulated. Samples prepared with distilled bitumen have shown a diffusion coefficient of the order of 10 -14 cm 2 /sec and those prepared with oxidized bitumen yielded a diffusion coefficient of the order of 10 -12 cm 2 /sec. Mathematical models of transport phenomena applied to cylindrical geometry were employed to fit experimental data. (Author) [pt

  20. Effects of the spaces available for cations in strongly acidic cation-exchange resins on the exchange equilibria by quaternary ammonium ions and on the hydration states of metal ions.

    Science.gov (United States)

    Watanabe, Yuuya; Ohnaka, Kenji; Fujita, Saki; Kishi, Midori; Yuchi, Akio

    2011-10-01

    The spaces (voids) available for cations in the five exchange resins with varying exchange capacities and cross-linking degrees were estimated, on the basis of the additivity of molar volumes of the constituents. Tetraalkylammonium ions (NR(4)(+); R: Me, Et, Pr) may completely exchange potassium ion on the resin having a larger void radius. In contrast, the ratio of saturated adsorption capacity to exchange capacity of the resin having a smaller void radius decreased with an increase in size of NR(4)(+) ions, due to the interionic contacts. Alkali metal ions could be exchanged quantitatively. While the hydration numbers of K(+), Rb(+), and Cs(+) were independent of the void radius, those of Li(+) and Na(+), especially Na(+), decreased with a decrease in void radius. Interionic contacts between the hydrated ions enhance the dehydration. Multivalent metal ions have the hydration numbers, comparable to or rather greater than those in water. A greater void volume available due to exchange stoichiometry released the interionic contacts and occasionally promoted the involvement of water molecules other than directly bound molecules. The close proximity between ions in the conventional ion-exchange resins having higher exchange capacities may induce varying interactions.

  1. Complexation ion-exchange chromatography of some metal ions on papers impregnated with Ti(IV)-based inorganic ion exchangers.

    Science.gov (United States)

    Sharma, S D; Gupta, R

    2000-02-01

    The chromatographic behavior of 40 metal ions is studied on titanium (IV) arsenate, titanium (IV) phosphate-, titanium (IV) molybdate-, titanium(IV) tungstate-, and titanium(IV) selenite-impregnated papers in 0.1M oxalic, citric, and tartaric acid as mobile phases. Similar studies are carried out on Whatman No. 1 papers for comparison. The ion-exchange capacity of these papers is determined, and their selectivity for different cations is discussed. The mechanism of migration is explained in terms of ion-exchange, precipitation, and adsorption. The prediction of elution sequence from RF values is also checked. The average Ri is found to be almost linearly dependent on the charge of the metal ions. The effect of the pKa of complexing acids on average RF values of 3d series metal ions is explained. A number of binary and ternary separations are achieved.

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

    International Nuclear Information System (INIS)

    Dosch, R.G.; Klavetter, E.A.; Stephens, H.P.; Brown, N.E.; Anthony, R.G.

    1996-08-01

    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

  3. A review of the radiation stability of ion exchange materials

    International Nuclear Information System (INIS)

    Pillay, K.K.S.

    1986-01-01

    A comprehensive literature survey on the radiation stability of synthetic organic ion exchangers was published in this journal (Vol. 97, No. 1.). This paper is a brief review of the major findings of this survey along with similar information on synthetic inorganic ion exchangers. The primary goal of this literature survey is to review present knowledge on the effects of ionizing radiations on synthetic ion exchange materials used in radiochemical processing. The information available in the literature shows some general trends in observed qualitative effects by different types of organic and inorganic ion exchange materials. (author)

  4. 309 plutonium recycle test reactor ion exchanger vault deactivitation report

    International Nuclear Information System (INIS)

    Griffin, P.W.

    1996-03-01

    This report documents the deactivation of the ion exchanger vault at the 309 Plutonium Recycle Test Reactor (PRTR) Facility in the 300 Area. The vault deactivation began in May 1995 and was completed in June 1995. The final site restoration and shipment of the low-level waste for disposal was finished in September 1995. The ion exchanger vault deactivation project involved the removal and disposal of twelve ion exchangers and decontaminating and fixing of residual smearable contamination on the ion exchanger vault concrete surfaces

  5. The Quantitative Ion Exchange Separation of Uranium from Impurities

    National Research Council Canada - National Science Library

    Narayanan, Usha

    1995-01-01

    .... This procedure involve adsorption of uranium onto Bio-Rad AG 1X8 or MP-1 ion exchange resins in 8 M HCl, separation of uncomplexed or weakly complexed matrix ions with an 8 M HCl wash, and subsequent...

  6. Large aperture contact ionized Cs+1 ion source for an induction linac

    International Nuclear Information System (INIS)

    Abbott, S.; Chupp, W.; Faltens, A.; Herrmannsfeldt, W.; Hoyer, E.; Keefe, D.; Kim, C.H.; Rosenblum, S.; Shiloh, J.

    1979-03-01

    A 500 KeV one-ampere Cs +1 ion beam has been generated by contact ionization with a 30 cm dia. iridium hot plate. Reproducibility of space charge limited ion current wave forms at repetition rates up to 1 Hz has been verified. The beam is characterized to be very bright and suitable as an ion source for the induction linac based heavy ion fusion scheme. The hot anode plate was found to be reliable and self-cleaning during the operation

  7. Development of a new all solid contact Cs"+ ion selective electrode

    International Nuclear Information System (INIS)

    Ramanjaneyulu, P.S.; Abha Naveen Kumar; Sharma, M.K.

    2017-01-01

    Studies were carried out to develop all solid contact cesium ion selective electrode with 25,27-bis(1-octyloxy)calix[4]arene-crown-6 as an ionophore. Polyaniline (PANI), deposited on Pt electrode by electrochemical method, was used as a transducer. Three different types of electrodes were made with variation in thickness of PANI film and gold nanoparticles doped PANI as transducers. The best response was observed with ISE having Au nanoparticles doped PANI as a transducer. The optimised ISE gave Nernstian response in the range 10"-"7 to 10"-"2 M with the slope of 55.0 ± 0.6 mV/decade of Cs"+. The response of ISE for Cs"+ is fairly constant above the pH 4. The developed ISE was successfully employed to determine Cs"+ in simulated high level nuclear waste solutions and CsCl spiked tap water samples. (author)

  8. Electrodeionization 2: the migration of nickel ions adsorbed in a flexible ion-exchange resin

    NARCIS (Netherlands)

    Spoor, P.B.; Veen, ter W.R.; Janssen, L.J.J.

    2001-01-01

    The removal of nickel ions from a low cross-linked ion-exchange resin using an applied electrical potential gradient was studied. The potential gradient across a bed of ion-exchange particles, in which nickel ions were absorbed, was varied by two methods. One involved a change of cell voltage across

  9. Exchange scattering of quasiparticles by positive ion in He3

    International Nuclear Information System (INIS)

    Ehdel'shtejn, V.M.

    1983-01-01

    The difference in the mobility of negative and positive ions in normal 3 He at low temperatures is discussed. The mobility mechanisms for the ions of different sign are qualitatively different since the positive ion can exchange quasiparticles with the helium atoms from the ice-like shell surrounding the ion. A study of the mobility in a magnetic field may yield quantitative information on the magnitude of the exchange interaction. A calculation for the exchange scattering model is carried out and it is shown that a logarithmic contribution to the positive ion mobility μsub(+)(T) appears which is analogous to the Kondo effect

  10. SYNTHESIS OF METHYL TERT-BUTYL ETHER CATALYZED BY ACIDIC ION-EXCHANGE RESINS - INFLUENCE OF THE PROTON ACTIVITY

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    1995-01-01

    The catalytic activity of various strong acid ion-exchange resins on the synthesis of methyl tert-butyl ether (MtBE) from methanol and isobutene has been investigated. Relative to Amberlyst 15, Kastel CS 381 and Amberlyst CSP have similar rate constants, whereas Duolite ES 276 and Amberlyst XE 307

  11. A self-calibrating ion beam profiler based on a CsI scintillator

    Energy Technology Data Exchange (ETDEWEB)

    Finocchiaro, P. E-mail: finocchiaro@lns.infn.it; Ciavola, G.; Cosentino, L.; Gu, M.; Raia, G.; Rovelli, A

    1999-11-21

    We report on the test results obtained with a prototype beam profiler based on a thin slit and a CsI scintillator, read out by means of a compact photomultiplier. Such a device has proven to be suitable to perform ion beam diagnostics at low and very low intensities. In particular, our device is suitable for being used in the energy and intensity ranges expected at the EXCYT radioactive ion beam facility, that is currently under development at LNS Catania.

  12. A self-calibrating ion beam profiler based on a CsI scintillator

    International Nuclear Information System (INIS)

    Finocchiaro, P.; Ciavola, G.; Cosentino, L.; Gu, M.; Raia, G.; Rovelli, A.

    1999-01-01

    We report on the test results obtained with a prototype beam profiler based on a thin slit and a CsI scintillator, read out by means of a compact photomultiplier. Such a device has proven to be suitable to perform ion beam diagnostics at low and very low intensities. In particular, our device is suitable for being used in the energy and intensity ranges expected at the EXCYT radioactive ion beam facility, that is currently under development at LNS Catania

  13. Treatment of spent ion-exchange resins

    International Nuclear Information System (INIS)

    Ghattas, N.K.; Ikladious, N.E.; Eskander, S.B.

    1981-01-01

    PMMA was studied with the aim to evaluate its usefulness as an incorporation medium for the final containment of spent ion-exchange resins. The study of the effect of water content (ranging from 25 to 100%) of the incorporated resin into PMMA on the compression strength of the final solid products shows that with the increasing water content the compression strength of the final products decreases sharply. Hardness of the final products follows nearly the same trend of compression strength. Increasing gamma irradiation doses, up to 7.77x10 7 rad, PMMA shows increase in compression strength and hardness for small doses and then decreases with increasing irradiation dose due to the increase in polymerization process and the degradation of the incorporation medium

  14. Effects of ionizing radiation on modern ion exchange materials

    International Nuclear Information System (INIS)

    Marsh, S.F.; Pillay, K.K.S.

    1993-10-01

    We review published studies of the effects of ionizing radiation on ion exchange materials, emphasizing those published in recent years. A brief overview is followed by a more detailed examination of recent developments. Our review includes styrene/divinylbenzene copolymers with cation-exchange or anion-exchange functional groups, polyvinylpyridine anion exchangers, chelating resins, multifunctional resins, and inorganic exchangers. In general, strong-acid cation exchange resins are more resistant to radiation than are strong-base anion exchange resins, and polyvinylpyridine resins are more resistant than polystyrene resins. Cross-linkage, salt form, moisture content, and the surrounding medium all affect the radiation stability of a specific exchanger. Inorganic exchangers usually, but not always, exhibit high radiation resistance. Liquid ion exchangers, which have been used so extensively in nuclear processing applications, also are included

  15. Comment on the effect of Cs on photon and secondary ion emission during sputtering

    International Nuclear Information System (INIS)

    Yu, M.L.

    1978-01-01

    The effect of Cs on photon and negative ion emission was discussed for the situations where the sputtered atom interacts either very weakly or very strongly with the target surface. The experimental data seem to favor the strong interaction case. 5 references

  16. Intrinsic Lead Ion Emissions in Zero-Dimensional Cs4PbBr6 Nanocrystals

    KAUST Repository

    Yin, Jun; Zhang, Yuhai; Bruno, Annalisa; Soci, Cesare; Bakr, Osman; Bredas, Jean-Luc; Mohammed, Omar F.

    2017-01-01

    -energy UV emission at approximately 350 nm to the allowed optical transition of 3P1 to 1S0 in Pb2+ ions and the low-energy UV emission at approximately 400 nm to the charge-transfer state involved in the 0D NC host lattice (D-state). In the emissive Cs4PbBr6

  17. Intrinsic Lead Ion Emissions in Zero-Dimensional Cs4PbBr6 Nanocrystals

    KAUST Repository

    Yin, Jun

    2017-11-07

    We investigate the intrinsic lead ion (Pb2+) emissions in zero-dimensional (0D) perovskite nanocrystals (NCs) using a combination of experimental and theoretical approaches. The temperature-dependent photoluminescence experiments for both “nonemissive” (highly suppressed green emission) and emissive (bright green emission) Cs4PbBr6 NCs show a splitting of emission spectra into high- and low-energy transitions in the ultraviolet (UV) spectral range. In the nonemissive case, we attribute the high-energy UV emission at approximately 350 nm to the allowed optical transition of 3P1 to 1S0 in Pb2+ ions and the low-energy UV emission at approximately 400 nm to the charge-transfer state involved in the 0D NC host lattice (D-state). In the emissive Cs4PbBr6 NCs, in addition to the broad UV emission, we demonstrate that energy transfer occurs from Pb2+ ions to green luminescent centers. The optical phonon modes in Cs4PbBr6 NCs can be assigned to both Pb–Br stretching and rocking motions from density functional theory calculations. Our results address the origin of the dual broadband Pb2+ ion emissions observed in Cs4PbBr6 NCs and provide insights into the mechanism of ionic exciton–optical phonon interactions in these 0D perovskites.

  18. TECHNICAL COMPARISON OF CANDIDATE ION EXCHANGE MEDIA FOR SMALL COLUMN ION EXCHANGE (SCIX) APPLICATIONS IN SUPPORT OF SUPPLEMENTAL LAW PRETREATMENT

    International Nuclear Information System (INIS)

    Ramsey, A.A.; Thorson, M.R.

    2010-01-01

    At-tank supplemental pretreatment including both filtration and small column ion exchange is currently under evaluation to facilitate salt waste retrieval and processing in the Hanford tank farms. Spherical resorcinol formaldehyde (sRF) resin is the baseline ion exchange resin for use in the Waste Treatment and Immobilization Plant (WTP). This document provides background and technical rationale to assist in determining whether spherical resorcinol formaldehyde (sRF) is also the appropriate ion exchange resin for supplemental LAW pretreatment processes and compares sRF with crystalline silicotitanate (CST) as potential supplemental pretreatment ion exchange media.

  19. Use of inorganic ion exchange materials for the treatment of liquid waste

    International Nuclear Information System (INIS)

    El-Naggar, I.M.; Zakaria, E.S.; El-Absy, M.A.; Abdel-Hamid, M.M.; Abo-Mesalam, M.M.; Shady, S.A.; Abdelwahab, M.A.; Aly, H.F.

    1997-01-01

    To examine the ion exchange behaviour of the double salts of polybasic acid with tetravalent metals type such as cerium(IV) and tin(IV) antimonates, different samples were prepared, heated at different temperatures and exposed to γ-irradiation. These samples were subject to X-ray, infra-red and thermal analysis. The exchange properties of the studied materials improved on increasing the Sb, Ce or Sn molar ratios and the drying temperature. The rate of the isotopic exchange was controlled by particle diffusion for the metal ions studied and was faster as the heating temperature was increased but slower for materials with a higher exchange capacity. The physical thermodynamic parameters have been evaluated which give some information regarding the mechanism of ion exchange on the surface of inorganic materials. The removal of radioactive isotopes of Na + , Cs + , Sr 2+ , Co 2+ and Eu 3+ was carried out by in-situ precipitation or by using preformed precipitate of tin(IV) and cerium(IV) antimonates. The products of in-situ precipitations act as ion exchange materials with high chemical and radioactive stabilities. The new materials have relatively high capacity compared with CeSb and SnSb. The irradiated cerium(IV) antimonate has been successfully used for the quantitative separation of cesium which suggests its use in the treatment of active liquid waste. (author). 24 refs, 7 figs, 17 tabs

  20. Ion exchange studies with ferrocyanide molybdate and zirconium phosphate in mixed solvent media. Part 1: Synthesis of the exchangers

    International Nuclear Information System (INIS)

    Ramaswamy, M.; Sunder Rajan, N.S.

    1979-01-01

    The present research forms the first part of the series on the investigation of the ion exchange behaviour of ferrocyanide molybdate(FeMo) and zirconium phosphate(ZrP) in water-alcohol and water-dioxane media. Since the above exchangers are not available indigenously, they were synthesized following published methods. That the reported methods of synthesis yield products with reproducible characteristics, were checked. pH titration of these two preparations in aqueous media showed that FeMo is a stronger acid than ZrP, the former, moreover, in its Cs + and Na + forms commence dissolving at pH values close to 5 and 2 respectively, and are completely dissolved at pH values 7.5 and 2.85 respectively. Titration curves with ZrP further indicated that as the pH increases, there occurs a reversal in the order of arrangement of Na + and Cs + curves, which reversal is attributed to a corresponding reversal of selectivity. Finally, both the chemical analysis and pH titration of FeMo confirm the existence of 4 replaceable H + ions corresponding to H 4 Fe(CN) 6 , a constituent of ferrocyanide molybdate, while those of ZrP are consistent with the empirical formula Zr(HPO 4 ) 2 .4.5 H 2 O, having two replaceable H + ions. (auth.)

  1. Waste treatment by selective mineral ion exchanger

    International Nuclear Information System (INIS)

    Polito, Aurelie

    2007-01-01

    STMI, subsidiary company of the AREVA Group with over 40 years in the D and D business, has been continuously innovating and developing new decontamination techniques, with the objectives of achieving more efficient decontaminations on a growing spectrum of media. In the field of liquid waste treatment, STMI manufactures uses and commercialises selective inorganic ion exchangers (RAN). These are hydrated synthetic inorganic compounds prepared from very pure raw materials. Different types of RANs (POLYAN, OXTAIN, Fe-Cu, Fe-CoK, Si-Fe-CoK) can be used to trap a large number of radioactive elements in contaminated effluents. Different implementations could be applied depending on technical conditions. STMI's offers consist in building global solution and preliminary design of installation either in dispersed form (batch) or in column (cartridge filtration). Those products are used all over the world not only in the nuclear business (Canada, US, Belgium, France...) but also in other fields. Indeed, it provides competitive solutions to many domains of application especially water pollution control, liquid waste treatment in the nuclear business by decreasing the activity level of waste. The following paper will focus on the theoretical principle of the mineral exchanger, its implementation and the feed back collected by STMI. (author)

  2. Methods for eluting radiocesium from zeolite ion exchange material in a column in the TMI-2 reactor containment building

    International Nuclear Information System (INIS)

    Knauer, J.B.; Campbell, D.O.; Collins, E.D.; King, L.J.

    1982-07-01

    Two alternative procedures were evaluated at Oak Ridge National Laboratory for potential use in eluting the radiocesium from Linde Ionsiv IE-95 zeolite in the pushcart ion exchange column in the TMI-2 containment building. The elution mechanism was iosotopic exchange of the radiocesium with stable cesium. Small zeolite ion exchange columns that had been loaded during ORNL tests of the Submerged Demineralizer System (SDS) flowsheet were eluted during these tests. One column was eluted using 0.25 M CsNO 3 , and a second column was eluted using 0.25 M CsH 2 BO 3 . Both eluent solutions were effective for removing the cesium. The 0.25 CsNO 3 eluent removed approx. 91% of the 137 Cs in 20 bed volumes and approx. 92% in 37.5 bed volumes. The 0.25 M CsH 2 BO 3 eluent removed approx. 82% of the 137 Cs in 20 bed volumes and approx. 85% in 40 bed volumes. In both cases, the radiation levels on the columns were reduced by a factor of approx. 30

  3. Thermal change and ion exchange properties of zeolite L with cesium and strontium

    International Nuclear Information System (INIS)

    Mimura, Hitoshi; Akiba, Kenichi

    1986-01-01

    Thermal change and ion exchange properties of Cs and Sr have been studied for zeolite L. The zeolite structure is stable below 900 deg C and converts to the amorphous phase above 1000 deg C. The cesium form of zeolite L recrystallized to pollucite (CsAlSi 2 O 6 ) by calcination at 1400 deg C for 1 h or under hydrothermal condition (300 deg C, 290 atm, 24 h). Hydrogen-form zeolites were prepared by the acid treatment in 10 -2 ∼ 10 -1 M HNO 3 solutions or thermal decomposition of NH 4 form zeolites at 460 ∼ 500 deg C. The distribution of Cs and Sr was dependent on equilibrium pH and the distribution coefficient (K d ) was about 10 4 (ml/g) at pH 5 ∼ 7. The exchange capacity of Cs and Sr was 0.89 (meq./g zeolite) and exchanging ratio was 68 % at D sites in main channel. These cations in zeolite were completely eluted with 10 -1 M HNO 3 solution. (author)

  4. The effect of organic ion-exchange resin on properties of heterogeneous ion-exchange membranes

    Czech Academy of Sciences Publication Activity Database

    Křivčík, J.; Vladařová, J.; Hadrava, J.; Černín, A.; Brožová, Libuše

    2010-01-01

    Roč. 14, - (2010), s. 179-184 ISSN 1944-3994. [Membrane Science and Technology Conference of Visegrad Countries /4./ PERMEA 2009, 07.07.2009-11.07.2009] R&D Projects: GA MPO FT-TA4/116 Institutional research plan: CEZ:AV0Z40500505 Keywords : heterogeneous ion-exchange membrane * membrane modification * particle size of distribution Subject RIV: CG - Electrochemistry Impact factor: 0.752, year: 2010

  5. Pyrolysis of Spent Ion Exchange Resins

    International Nuclear Information System (INIS)

    Braehler, Georg; Slametschka, Rainer

    2012-09-01

    Ion exchangers (IEX in international language) are used to remove radionuclides from the primary coolant in all nuclear power stations with a water cooling circuit. This is done by continuously removing a volume of coolant from the primary circuit and passing it through coolers, filters and the ion exchange beds. Cation and anion exchangers, in the form of coarse-grained resin beads in pressurized-water reactors and as finely ground powdered resins in boiling water reactors, are used. The trend for new power stations is to exploit all the possibilities for avoiding the generation of contaminated liquids and then to clean, as far as possible, the solutions that are nevertheless generated using ion exchange for it to be possible to dispose of them as non-radioactive waste. This relieves the burden on evaporator facilities, or means that these can even be dispensed with entirely. Regeneration is possible in principle, but little use is made of it. As the regeneration usual in conventional technologies is not employed in nuclear power stations, it is necessary to dispose of this material as radioactive waste. On the international level, a great number of processes are offered that are intended to meet the relevant national regulations, and these will be discussed in brief with their advantages and disadvantages. The aim is then to find a process which reduces the volume, yields an inert or mineralized product, works at temperatures of no more than approximately 600 deg. C and can be run in a simple facility. Originally, the pyrolysis process was developed to treat liquid organic waste from reprocessing. A typical application is the decomposition of spent solvent (TBP, tributyl phosphate, mixed with kerosene). In this process TBP is pyrolyzed together with calcium hydroxide in a fluidized bed facility at temperatures of around 500 deg. C, the calcium hydroxide reacts with the phosphate groups directly to form calcium pyrophosphate which contains all the radioactivity

  6. Development of long-lived radionuclide partitioning technology - Preparation of ion exchanges for selective separation of radioactive elements

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Si Joong; Jeong, Hae In; Shim, Min Sook [Korea University, Seoul (Korea, Republic of); Kim, Jeong [Seonam University, Namwon (Korea, Republic of)

    1995-07-01

    Ion exchanger contained nitrogen-oxygen donor macrocyclic units was synthesized, and immobilization process was carried out by adsorption of the exchanger to silica gel. The binding constants were measured with acid concentration. From the binding constants, selectivity for Pt(II) ion and acid concentration of eluents were determined. The most optimum conditions for the separation were also determined from investigating the effects of amount of immobile phase and column length. And liarit aza-crown ethers were synthesized and selectively separated Cs/Sr ion from mixed metal solution. 37= refs., 24 tabs., 40 figs. (author)

  7. Investigations on Cs-free alternative materials for negative hydrogen ion formation

    Energy Technology Data Exchange (ETDEWEB)

    Kurutz, Uwe

    2017-01-19

    Neutral beam injection (NBI) represents a main auxiliary heating and current drive system for thermonuclear fusion devices. For ITER, a total heating power of up to 33 MW will be delivered for up to one hour pulses at particle energies of up to 1 MeV by two NBI systems. The respective ion sources will therefore have to allow for the extraction and acceleration of negative hydrogen ions at a current density of 200 A/m{sup 2} from a low pressure low temperature hydrogen plasma. Also for the succeeding demonstration reactor DEMO the application of NBI is currently discussed. Respective systems will, however, have to fulfil even higher demands, like higher powers (up to 135 MW), longer pulse lengths (2 h or even cw operation), and more restrictive constrains regarding the reliability and stability. Today efficient NBI negative hydrogen ion sources are based mainly on the conversion of positive hydrogen ions and/or hydrogen atoms at a grid surface coated with caesium. Cs is used for reducing the grid's work function which significantly enhances the particle conversion probability. However, the alkali metal is chemically very reactive and easily forms compounds with residual gas impurities. Furthermore, complex redistribution dynamics of the deposited Cs layer is given. This inherently links the application of Cs with a temporal and spatial non-stability of the negative ion yield, which contradicts the required reliability of a DEMO NBI system. Thus, for DEMO, Cs-free alternative materials for negative ion formation are investigated within this work at a flexible laboratory experiment. An ECR discharge is used which provides comparable parameters (pressure, densities, particle fluxes and -energies) to the NBI ion sources. Negative ion formation is measured above different material samples via laser photodetachment together with global plasma parameters using a Langmuir probe and optical emission spectroscopy. The plasma parameters are used for modelling the

  8. Investigations on Cs-free alternative materials for negative hydrogen ion formation

    International Nuclear Information System (INIS)

    Kurutz, Uwe

    2017-01-01

    Neutral beam injection (NBI) represents a main auxiliary heating and current drive system for thermonuclear fusion devices. For ITER, a total heating power of up to 33 MW will be delivered for up to one hour pulses at particle energies of up to 1 MeV by two NBI systems. The respective ion sources will therefore have to allow for the extraction and acceleration of negative hydrogen ions at a current density of 200 A/m 2 from a low pressure low temperature hydrogen plasma. Also for the succeeding demonstration reactor DEMO the application of NBI is currently discussed. Respective systems will, however, have to fulfil even higher demands, like higher powers (up to 135 MW), longer pulse lengths (2 h or even cw operation), and more restrictive constrains regarding the reliability and stability. Today efficient NBI negative hydrogen ion sources are based mainly on the conversion of positive hydrogen ions and/or hydrogen atoms at a grid surface coated with caesium. Cs is used for reducing the grid's work function which significantly enhances the particle conversion probability. However, the alkali metal is chemically very reactive and easily forms compounds with residual gas impurities. Furthermore, complex redistribution dynamics of the deposited Cs layer is given. This inherently links the application of Cs with a temporal and spatial non-stability of the negative ion yield, which contradicts the required reliability of a DEMO NBI system. Thus, for DEMO, Cs-free alternative materials for negative ion formation are investigated within this work at a flexible laboratory experiment. An ECR discharge is used which provides comparable parameters (pressure, densities, particle fluxes and -energies) to the NBI ion sources. Negative ion formation is measured above different material samples via laser photodetachment together with global plasma parameters using a Langmuir probe and optical emission spectroscopy. The plasma parameters are used for modelling the inherently

  9. Development of heat resistant ion exchange resin. First Report

    International Nuclear Information System (INIS)

    Onozuka, Teruo; Shindo, Manabu

    1995-01-01

    In nuclear power stations, as a means of maintaining the soundness of nuclear reactors, the cleaning of reactor cooling water has been carried out. But as for the ion exchange resin which is used as the cleaning agent in the filtrating and desalting facility in reactor water cleaning system, since the heat resistance is low, high temperature reactor water is cooled once and cleaned, therefore large heat loss occurs. If the cleaning can be done at higher temperature, the reduction of heat loss and compact cleaning facilities become possible. In this study, a new ion exchange resin having superior heat resistance has been developed, and the results of the test of evaluating the performance of the developed ion exchange resin are reported. The heat loss in reactor water cleaning system, the heat deterioration of conventional ion exchange resin, and the development of the anion exchange resin of alkyl spacer type are described. The outline of the performance evaluation test, the experimental method, and the results of the heat resistance, ion exchange characteristics and so on of C4 resin are reported. The with standable temperature of the developed anion exchange resin was estimated as 80 - 90degC. The ion exchange performance at 95degC of this resin did not change from that at low temperature in chloride ions and silica, and was equivalent to that of existing anion exchange resin. (K.I.)

  10. Development of heat resistant ion exchange resin. First Report

    Energy Technology Data Exchange (ETDEWEB)

    Onozuka, Teruo; Shindo, Manabu [Tohoku Electric Power Co., Inc., Sendai (Japan)

    1995-01-01

    In nuclear power stations, as a means of maintaining the soundness of nuclear reactors, the cleaning of reactor cooling water has been carried out. But as for the ion exchange resin which is used as the cleaning agent in the filtrating and desalting facility in reactor water cleaning system, since the heat resistance is low, high temperature reactor water is cooled once and cleaned, therefore large heat loss occurs. If the cleaning can be done at higher temperature, the reduction of heat loss and compact cleaning facilities become possible. In this study, a new ion exchange resin having superior heat resistance has been developed, and the results of the test of evaluating the performance of the developed ion exchange resin are reported. The heat loss in reactor water cleaning system, the heat deterioration of conventional ion exchange resin, and the development of the anion exchange resin of alkyl spacer type are described. The outline of the performance evaluation test, the experimental method, and the results of the heat resistance, ion exchange characteristics and so on of C4 resin are reported. The with standable temperature of the developed anion exchange resin was estimated as 80 - 90degC. The ion exchange performance at 95degC of this resin did not change from that at low temperature in chloride ions and silica, and was equivalent to that of existing anion exchange resin. (K.I.).

  11. Oxidation of cyclohexane catalyzed by metal-ion-exchanged zeolites.

    Science.gov (United States)

    Sökmen, Ilkay; Sevin, Fatma

    2003-08-01

    The ion-exchange rates and capacities of the zeolite NaY for the Cu(II), Co(II), and Pb(II) metal ions were investigated. Ion-exchange equilibria were achieved in approximately 72 h for all the metal ions. The maximum ion exchange of metal ions into the zeolite was found to be 120 mg Pb(II), 110 mg Cu(II), and 100 mg Co(II) per gram of zeolite NaY. It is observed that the exchange capacity of a zeolite varies with the exchanged metal ion and the amount of metal ions exchanged into zeolite decreases in the sequence Pb(II) > Cu(II) > Co(II). Application of the metal-ion-exchanged zeolites in oxidation of cyclohexane in liquid phase with visible light was examined and it is observed that the order of reactivity of the zeolites for the conversion of cyclohexane to cyclohexanone and cyclohexanol is CuY > CoY > PbY. It is found that conversion increases by increase of the empty active sites of a zeolite and the formation of cyclohexanol is favored initially, but the cyclohexanol is subsequently converted to cyclohexanone.

  12. Comments on H- volume production in Cs-seeded ion sources. Appendix I

    International Nuclear Information System (INIS)

    Peterson, J.R.

    1986-01-01

    Considerable interest was generated at the IAEA Negative Ion Beam Workshop in Grenoble, France, in March, 1985, by a report from the Kurchatov Institute on the development of a 2-ampere steady-state H - ion source, in which the ions were volume-produced in a discharge in H 2 , seeded with Cs vapor. The mechanism primarily responsible for this remarkably high current from a volume production source was not yet understood, but it was tentatively presumed to involve the collisional energy transfer from electronically excited Cs 6p atoms into H 2 vibrations. In any case, it was apparently different from the surface-plasma interactions that have been assumed to control the H - production in the Dudnikov-Dimov type sources

  13. Study of the secondary negative ion emission of copper and several of its alloys by impact with Cs+ ions

    International Nuclear Information System (INIS)

    Vallerand, P.; Baril, M.

    1977-01-01

    Secondary ion emission studies have been undertaken using Cs + as the primary ion beam. A good vacuum (ca. 10 -8 torr) is needed to eliminate contamination by residual gases. Negative ion emission of pure copper is compared with its alloys. The thermodynamic equilibrium model of Andersen is discussed. For low element concentrations, the experimental data show enhancement in negative emission of P, Al, Fe, Sn, Ni, and attenuation for Zn, Pb. The order of magnitude of ionic efficiency S - for copper is evaluated at 10 -4 . (Auth.)

  14. Effect of alkali ions (Na+, K+, Cs+) on reaction mechanism of CZTS nano-particles synthesis

    Science.gov (United States)

    Kumar, Suresh; Altosaar, Mare; Grossberg, Maarja; Mikli, Valdek

    2018-04-01

    The control of morphology, elemental composition and phase composition of Cu2ZnSnS4 (CZTS) nano-crystals depends on the control of complex formation and surface stabilization of nano-particles in solution-based synthesis in oleylamine. At temperatures ≥280 °C, the control of nano-crystal's morphology and homogenous growth is difficult because of fast poly-nuclear growth occurring at higher temperatures. In the present work the effect of oleylamine complex formation with different alkali ions (Na+, K+ and Cs+) on nano-crystals growth at synthesis temperature of 280 °C was studied. It was found that nano-powders synthesized in the presence of Na+ and K+ ions showed the formation of crystals of different sizes - small nano-particles (18 nm-30 nm), large aggregated crystals (few nm to 1 μm) and large single crystals (1 μm - 4 μm). The presence of Cs+ ions in the nano-powder synthesis in oleylamine-metal precursor-CsOH solution promoted growth of nano-crystals of homogenous size. It is proposed that the formed oleylamine-Cs complexes a) enhance the formation and stabilization of oleylamine-metal (Cu, Zn and Sn) complexes before the injection of sulphur precursor into the oleylamine-metal precursor solution and b) after addition of sulphur stabilize the fast nucleated nano-particles and promote diffusion limited growth.

  15. Composite inorganic ion-exchangers and their applications

    International Nuclear Information System (INIS)

    Sebesta, F.; John, J.; Motl, A.

    1998-01-01

    Composite inorganic ion exchangers are described containing modified polyacrylonitrile as the binding polymer. An overview of existing composite ion exchangers is presented, and the universality and assets of the developed procedure of treatment of inorganic ion exchanger powders are highlighted. Examples of applicability of the ion exchangers to the separation and concentration of radionuclides include in particular: wastes from the operation of nuclear power plants, contaminated surface waters and ground water, high level radioactive wastes from spent fuel reprocessing, and wastewaters from uranium ore mining and milling. In addition, composite ion exchangers find use in the monitoring of contamination of the hydrosphere and the environment and in the investigation of radionuclide migration in surface waters and ground water

  16. Implanting very low energy atomic ions into surface adsorbed cage molecules: the formation/emission of Cs/C60+

    International Nuclear Information System (INIS)

    Kolodney, Eli; Kaplan, Andrey; Manor, Yoni; Bekkerman, Anatoly; Tsipinyuk, Boris

    2004-01-01

    Full Text: We demonstrate the formation of an endo-complex via a collision of energetic ions with molecular overlayers on a surface. An incoming atomic ion is encapsulated inside a very large molecule or cluster by implanting the primary ion into the target species, which then recovers its original structure or rearrange itself around the implanted ion in some stable configuration. Here we describe an experiment resulting in the formation and ejection of an endo-complex, within a single collision. We study the formation and emission of endohedral fullerenes, Cs/C 60 + and Cs/C 70 + , following a single collision of Cs + ion with a sub-monolayer of C 60 (steady state coverage) on gold and silicon surfaces and with a sub-monolayer of C 70 on gold. A continuous low energy (E 0 =35-220 eV) Cs + ion beam hit the Cs + covered surface and the collisional formation and ejection of the endohedral Cs/Cs 60 + complex, within a single Cs + /C 60 collision was observed and characterized. Several experimental observations clearly demonstrate the single collision nature of the combined atom penetration endo-complex ejection event. The fullerene molecule is actually being picked up off the surface by the penetrating Cs + ion. The evidence for the trapping of the Cs + ion inside the fullerene cage is given both by the appearance of the Cs/Cs (602-2n) + (n=1-5) sequence and its termination at Cs/Cs 50 + . Kinetic Energy Distributions (KEDs) of the outgoing Cs/Cs 60 + were measured for two different Cs + impact energies under field-free conditions. The most striking observation is the near independence of the KEDs on the impact energy. Both KEDs peak around 1.2 eV with similar line shapes. A simple model for the formation/ejection/fragmentation dynamics of the endohedral complex is proposed and is found to be in good agreement with the experimental results

  17. Study on actinoid isolation by antimonide ion exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Tsuji, Masamichi [Tokyo Inst. of Tech. (Japan). Faculty of Science; Kubota, Masumitsu; Yamagishi, Isao

    1996-01-01

    To establish a containment of long-life nuclides and an effective reduction of waste volume is important to reduce the loadings on the natural environment. Chemical isolation of radioactive nuclides from wastes was attempted by using inorganic ion exchanger with high specificity and thermal stability. In this study, titanium antimonide was used as an ion exchanger to investigate the adsorption of trivalent metallic ions according to Kielland plot curves. When the ionic equivalent fraction (X-bar{sub M}) was around 0.005, Kielland plot curve of either of 3-valent metallic ions was bent, suggesting the exchanger had two different adsorption sites. The slope of the curve became smaller as an elevation of temperature. These results show that the ion radius was decreased resulting from partial elimination of the hydrated water of ion and thus, the steric conditions around the exchange site might be improved. (M.N.)

  18. Thermodynamics of ion exchange equilibrium for some uni ...

    African Journals Online (AJOL)

    The study on thermodynamics of ion exchange equilibrium for uni-univalent Cl-/I-, Cl-/Br-, and uni-divalent Cl-/SO42-, Cl-/C2O42- reaction systems was carried out using ion exchange resin Indion FF-IP. The equilibrium constant K was calculated by taking into account the activity coefficient of ions both in solution as well as ...

  19. Rod-shaped ion exchanger useful for purifying liquids or recovering components from liquids comprises a metal wire core surrounded by an ion-exchange resin

    NARCIS (Netherlands)

    Koopman, C.; Witkamp, G.J.

    2002-01-01

    Rod-shaped ion exchanger comprises a metal wire core surrounded by an ion-exchange resin. Independent claims are also included for: (1) a module comprising a housing with an inlet and outlet and one or more ion exchangers as above; (2) a process for producing an ion exchanger as above, comprising

  20. Application of ion exchange processes for the treatment of radioactive waste and management of spent ion exchangers

    International Nuclear Information System (INIS)

    2002-01-01

    This report describes the ion exchange technologies currently used and under development in nuclear industry, in particular for waste management practices, along with the experience gained in their application and with the subsequent handling, treatment and conditioning of spent ion exchange media for long term storage and/or disposal. The increased role of inorganic ion exchangers for treatment of radioactive liquid waste, both in nuclear power plant operations and in the fuel reprocessing sector, is recognised in this report. The intention of this report is to consolidate the previous publications, document recent developments and describe the state of the art in the application of ion exchange processes for the treatment of radioactive liquid waste and the management of spent ion exchange materials

  1. Ion exchange nonwoven fabric chemical filter. 2

    International Nuclear Information System (INIS)

    Sekiguchi, Hideaki

    2000-01-01

    This report outlined the characteristics of EPIX filter and its complex with activated carbon to eliminate organic compounds from solvent. Elimination performance of this filter was determined using an ion chromatographic analyzer. EPIX filter showed high performance to eliminate trace amount of ionic compounds. The rate of elimination was both 99% or more for NH 3 and SO 2 in an early phase of filtration. Release of dust as well as impurities was significantly reduced by the use of EPIX filter. Gases once adsorbed on the filter were not released even at an elevated temperature of atmosphere. Combined use of non-woven fabrics was possible. For EPIX filter, there are three kinds; strong acid cation exchange filter and strong/weak basic anion filters. The weak basic anion filter has been applied to the conventional apparatus in wafer makers because the filter was very effective for selective boron trapping. When polyethyleneterephthalate was used as the base polymer, radical groups produced on the polymer were co-polymerized with monomer substances. The lifetime of filter was estimated on a base of gas concentration and wind velocity to determine the time to replace with a new one. Furthermore, the loss of pressure became less than a half when EPIX filter was used. (M.N.)

  2. Uranium refining process using ion exchange membrane

    International Nuclear Information System (INIS)

    Yamaguchi, Akira

    1977-01-01

    As for the method of refining uranium ore being carried out in Europe and America at present, uranium ore is roughly refined at the mine sites to yellow cake, then this is transported to refineries and refined by dry method. This method has the following faults, namely the number of processes is large, it requires expensive corrosion-resistant materials because of high temperature treatment, and the impurities in uranium tend to increase. On the other hand, in case of EXCER method, treatment is carried out at low temperature, and high purity uranium can be obtained, but the efficiency of electrolytic reduction process is extremely low, and economically infeasible. In the wet refining method called PNC process, uranium tetrafluoride is produced from uranium ore without making yellow cake, therefore the process is rationalized largely, and highly economical. The electrolytic reduction process in this method was developed by Asahi Chemical Industry Co., Ltd. by constructing the pilot plant in Ningyotoge Mine. The ion exchange membrane, the electrodes, and the problems concerning the process and the engineering for commercial plants were investigated. The electrolytic reduction process, the pilot plant, the development of the elements of electrolytic cells, the establishment of analytical process, the measurement of the electrolytic characteristics, the demonstration operation, and the life time of the electrolytic diaphragm are reported. (Kako, I.)

  3. Pyrolysis of spent ion-exchanger resins

    International Nuclear Information System (INIS)

    Slametschka, Rainer; Braehler, Georg

    2012-01-01

    Initial tests have shown that ion exchangers (IEX) can be decomposed by pyrolysis with very good results, yielding an inert and chemically resistant product. No additives are necessary. The main constituent of the product, the pyrolysis residues or ash, is carbon. It has been discovered that the entire radioactive inventory remains in the pyrolysis residues during pyrolysis of the IEX. This is achieved by relatively low process temperatures that prevent highly volatile nuclides such as the caesium nuclides from passing into the gaseous phase. Sintered metal filters in pyrolysis plant ensure that even the radioactivity bonded to the dust remains in the pyrolysis residues. In addition to the radionuclides, the main constituents of the residue are carbon from the original polystyrene matrix and sulphur from the functional groups. The pyrolysis residues form a flowable solid material and not a melt. It is thus easy to handle and can be compacted or cemented, depending on the requirements for interim and permanent storage. Any further constituents such as inorganic filter materials or even other organic materials do not interfere with the process, they are dried, calcined or also pyrolysed. (orig.)

  4. Ion exchange fiber prepared by radiation grafting, (2)

    International Nuclear Information System (INIS)

    Sekiguchi, Hideaki; Fujiwara, Kunio; Fujii, Toshiaki; Takai, Takeshi; Kobayashi, Atsushi

    1991-01-01

    Ion exchange fiber prepared by radiation grafting has the capabilities for wide application as high performance materials. Extensive studies were made to evaluate the ion exchange fiber prepared by radiation grafting for removing some toxic or malodorous gases, continuing from the previous work (presented in Ebara Engng. Review, No. 146), in which the ability of removing ammonia with cation exchange fiber was investigated. The results of this study can be summarized by the following conclusions: (1) Methods of evaluating the ability of removing ammonia, acetaldehyde, and some lower fatty acids in low concentration were established, (2) Besides being effective for the removal of acidic or basic gases, neutral gas such as acetaldehyde can also be removed by adding some functional compounds to the ion exchange fiber, and (3) Ion exchange fiber prepared by radiation grafting is effective as a deodorizing filter. (author)

  5. Study of kinetics, equilibrium and isotope exchange in ion exchange systems Pt. 4

    International Nuclear Information System (INIS)

    Stamberg, K.; Plicka, J.; Calibar, J.; Gosman, A.

    1985-01-01

    The kinetics of ion exchange in the Nasup(+)-Mgsup(2+)-strongly acidic cation exchanger system in a batch stirred reactor was studied. The samples of exchangers OSTION KS (containing DVB in the range of 1.5 - 12%) and AMBERLITE IR 120 for experimental work were used; the concentration of the aqueous nitrate solution was always 0.2M. The Nernst-Planck equation for description of diffusion of ions in a particle was used. The values of diffusion coefficients of magnesium ions in the exchangers and their dependence on the content of DVB were obtained by evaluating the experimental data and using the self-diffusion coefficients of sodium. (author)

  6. High-energy particle emission from galena and pyrite bombarded with Cs and O ions

    International Nuclear Information System (INIS)

    Karpuzov, D.S.; McIntyre, N.S.

    2002-01-01

    The ejection of energetic particles during steady-state ion surface bombardment has been investigated by means of a dynamic computer simulation as well as in a secondary ion mass spectrometry (SIMS)/low-energy ion scattering from surfaces (LEIS) experiment. The emphasis of this comparative study is on the mass dependence of high-energy tails in sputtering and backscattering for the bombardment of galena (PbS) and pyrite (FeS 2 ) with keV energy ion beam of cesium and oxygen. In the experiment, kinetic energy distributions of sputtered secondary ions (S + , Fe + , Pb + , S - ), as well as backscattered or re-sputtered primary ions (Cs + , O + , O - ), have been measured on a modified Cameca IMS-3f magnetic sector mass spectrometer for keV cesium (Cs + ) and oxygen (O 2 + , O - ) bombardment of galena and pyrite. Ejection of high-energy particles, with emission energies of up to ∼40% or up to ∼60% of the bombarding energy for sputtering of the lighter component (S ± ) with cesium or oxygen, respectively, and of up to ∼40% (Cs + ) and ∼80% (O ± ) for backscattering, has been observed for PbS. The computer simulations were based on the well-known MARLOWE code. In order to model the change of the stoichiometry of the binary compounds, dynamic modification of the target composition in the near-surface region was introduced. Cs incorporation was included, and a relative enrichment of the metallic component (Pb, Fe) in the top few layers due to preferential sputtering of sulfur was allowed. The computer simulations provide information on the formation of altered layer under sputter equilibrium as well as on the energy and angular emission distributions of sputtered and backscattered particles in steady-state conditions. Multiple scattering of Cs projectiles and dynamic re-sputtering of cesium that was previously incorporated in the altered near-surface region can be distinguished in the simulation, and matched with the experimental observations. In addition

  7. Gadolinium-hydrogen ion exchange of zirconium phosphate

    Science.gov (United States)

    Liu, D. C.; Power, J. L.

    1972-01-01

    The Gd(+3)/H(+) ion exchange on a commercial zirconium phosphate ion exchanger was investigated in chloride, sulfate, and phosphate solutions of Gd(+3) at gadolinium concentrations of 0.001 to 1 millimole per cc and in the pH range of 0 to 3.5. Relatively low Gd(+3) capacities, in the range of 0.01 to 0.1 millimole per g of ion exchanger were found at room temperature. A significant difference in Gd(+3) sorption was observed, depending on whether the ion exchanger was converted from initial conditions of greater or lesser Gd(+3) sorption than the specific final conditions. Correlations were found between decrease in Gd(+3) capacity and loss of exchanger phosphate groups due to hydrolysis during washing and between increase in capacity and treatment with H3PO4. Fitting of the experimental data to ideal ion exchange equilibrium expressions indicated that each Gd(+3) ion is sorbed on only one site of the ion exchanger. The selectivity quotient was determined to be 2.5 + or - 0.4 at room temperature on gadolinium desorption in chloride solutions.

  8. Ion exchange kinetics of alkaline earths on Zr(IV) arsenosilicate cation exchanger

    International Nuclear Information System (INIS)

    Varshney, K.G.; Agrawal, S.; Varshney, K.

    1984-01-01

    A new approach based on the Nernst-Planck equations was applied to study the ion exchange kinetics for the exchange reactions of Mg(II), Ca(II), Sr(II) and Ba(II) with H + -ions at various temperatures on the zirconium(IV) arsenosilicate phase. Under the conditions of particle diffusion, the rate of exchange was found to be independent of the metal ion concentration at and above 0.1 M in aqueous medium. Energy and entropy of activation were determined and found to vary linearly with the ionic radii and mobilities of alkaline earths, a unique feature observed for an inorganic ion exchanger. The results are useful for predicting the ion exchange processes occurring on the surface of an inorganic material of the type studied. (author)

  9. 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)

    Brown, G.N.; Bontha, J.R.; Carlson, C.D.

    1995-09-01

    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

  10. Study of kinetics, equilibrium and isotope exchange in ion exchange systems Pt. 6

    International Nuclear Information System (INIS)

    Plicka, J.; Stamberg, K.; Cabicar, J.; Gosman, A.

    1986-01-01

    The description of kinetics of ion exchange in ternary system was based upon three Nernst-Planck equations, each of them describing the particle diffusion flux of a given counterion as an independent process. For experimental verification, the strongly acidic cation exchanger OSTION KS 08 the shallow-bed technique, and 0.2 mol x dm -3 aqueous nitrate solutions were chosen. The kinetics of ion exchange in the system of cations Na + - Mg 2+ - UO 2 2+ was studied. The values of diffusion coefficients obtained by evaluating of kinetics of isotope exchange and binary ion exchange were used for calculation. The comparison of calculated exchange rate curves with the experimental ones was made. It was found that the exchanging counterions were affected by each other. (author)

  11. Immobilization of inorganic ion-exchanger into bio-polymer foams - Application to cesium sorption

    International Nuclear Information System (INIS)

    Vincent, Chloe; Hertz, Audrey; Barre, Yves; Vincent, Thierry; Guibal, Eric

    2014-01-01

    Nickel-potassium ferrocyanide (along with other ferrocyanide sub-products, as shown by mineralization, SEM-EDX and XRD 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). Cesium sorption is hardly affected by the pH between pH 2 and 8. The sorbent is selective to Cs(I) even in the presence of high concentrations of Na(I), K(I), Rb(I) or NH 4+ . 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. In fixed-bed columns, the breakthrough curve is accurately described by the Clark model and the sorption capacity (at sorbent saturation) is consistent with the values obtained in sorption isotherms. Preliminary tests performed on 137 Cs spiked solutions confirm the efficiency of the material for the treatment of effluents bearing radionuclides. (authors)

  12. Ion-exchange properties of microporous tungstates: novel adsorbents for nuclear waste management applications

    International Nuclear Information System (INIS)

    Griffith, C.S.; Luca, V.; Eddowes, R.C.; Keegan, E.A.; Scales, N.

    2003-01-01

    A hydrothermally prepared tungsten oxide-based phase, ATS-1 (ANSTO Tungstate Sorbent), of nominal composition, Na 0.3 Mo 0.1 W 0.9O3 .χH 2 O, has been shown to display promising selectivity for both Cs + and Sr 2+ cations from acidic simulant, indicative of the Intermediate Level Liquid Waste (ILLW) produced from 99 Mo radioisotope production at the ANSTO site. The development of an inorganic ion-exchanger that displays such selectivity for both Cs + and Sr 2+ in acidic solutions has previously eluded researchers in the field of inorganic ion-exchangers. The ATS-1 adsorbent also displays exquisite selectivity for lead (and polonium) in low to high acidity solutions, and as such is being further investigated as a method to reduce the radiological hazard from 210 Pb and 210 Po during the processing of uranium ore bodies. The adsorption of Cs + , Sr 2+ and Pb 2+ cations by ATS-1 has been extensively investigated with respect to the kinetics of adsorption, capacity and the effect of competing cations viz. Na + , K + . The ATS-1 adsorbent has also been successfully granulated with an inert, organic matrix, which has consequently allowed the study of cation adsorption using more application-based, column separations. The results of these investigations suggest that these materials have potential application in several nuclear waste management issues in Australia at the present

  13. Ion exchange resins as high-dose radiation dosimeters

    International Nuclear Information System (INIS)

    Alian, A.; Dessouki, A.; El-Assay, N.B.

    1984-01-01

    This paper reports on the possibility of using various types of ion exchange resins as high-dose radiation dosimeters, by analysis of the decrease in exchange capacity with absorbed dose. The resins studied are Sojuzchim-export-Moscow Cation Exchanger KU-2 and Anion Exchanger AV-17 and Merck Cation Exchanger I, and Merck Anion Exchangers II and III. Over the dose range 1 to 100 kGy, the systems show linearity between log absorbed dose and decrease in resin ion exchange capacity. The slope of this response function differs for the different resins, depending on their ionic form and degree of cross-linking. The radiation sensitivity increases in the order KU-2; Exchanger I; AV-17; Exchanger II; Exchanger III. Merck resins with moisture content of 21% showed considerably higher radiation sensitivity than those with 2 to 3% moisture content. The mechanism of radiation-induced denaturing of the ion exchanger resins involves cleavage and decomposition of functional substituents, with crosslinking playing a stabilizing role, with water and its radiolytic products serving to inhibit radical recombination and interfering with the protection cage effect of crosslinking. (author)

  14. Development of composite ion exchangers and their use in treatment of liquid radioactive wastes

    International Nuclear Information System (INIS)

    Sebesta, F.; John, J.; Motl, A.

    1997-01-01

    Composite inorganic-organic absorbers represent a group of inorganic ion exchangers modified by using binding organic material for preparation of larger size particles having higher granular strength. Such modification of originally powdered or microcrystalline inorganic ion exchangers makes their application in packed beds possible. Modified polyacrylonitrile (PAN) has been used as a universal binding polymer for a number of inorganic ion exchangers. The kinetics of ion exchange and sorption capacity of such composite absorbers is not influenced by the binding polymer mentioned above. The contents of active component in composite absorber can be varied over a very broad range (5-95% of the dry weight of the composite absorber). These composite absorbers have been tested for separation and concentration of various contaminants from aqueous solutions. Their high selectivity and sorption efficiency are advantageous for treatment of various radioactive and/or industrial waste waters, removal of natural and/or artificial radionuclides and heavy or toxic metals from underground water, determination of radionuclides ( 137 Cs, 60 Co, U, Ra) in the environment, etc. Examples of some of these applications are presented in this report. (author). 21 refs, 9 figs, 10 tabs

  15. Decontamination and dismantlement of the building 594 waste ion exchange facility at Argonne National Laboratory-East project final report

    International Nuclear Information System (INIS)

    Wiese, E. C.

    1998-01-01

    The Building 594 D and D Project was directed toward the following goals: Removal of any radioactive and hazardous materials associated with the Waste Ion Exchange Facility; Decontamination of the Waste Ion Exchange Facility to unrestricted use levels; Demolition of Building 594; and Documentation of all project activities affecting quality (i.e., waste packaging, instrument calibration, audit results, and personnel exposure) These goals had been set in order to eliminate the radiological and hazardous safety concerns inherent in the Waste Ion Exchange Facility and to allow, upon completion of the project, unescorted and unmonitored access to the area. The ion exchange system and the resin contained in the system were the primary areas of concern, while the condition of the building which housed the system was of secondary concern. ANL-E health physics technicians characterized the Building 594 Waste Ion Exchange Facility in September 1996. The characterization identified a total of three radionuclides present in the Waste Ion Exchange Facility with a total activity of less than 5 microCi (175 kBq). The radionuclides of concern were Co 60 , Cs 137 , and Am 241 . The highest dose rates observed during the project were associated with the resin in the exchange vessels. DOE Order 5480.2A establishes the maximum whole body exposure for occupational workers at 5 rem (50 mSv)/yr; the administrative limit at ANL-E is 1 rem/yr (10 mSv/yr)

  16. Adsorption behaviour and kinetics of exchange of Zn2+ and Eu3+ ions on a composite ion exchanger

    International Nuclear Information System (INIS)

    Morcos, T.N.

    2007-01-01

    Equilibria and kinetics of exchange of both Zn2+ and Eu3+ ions on a composite ion-exchanger, cobalt hexacyanocobaltate (III) (CoHCC) incorporated in polyacrylonitrile (PAN), has been studied. The apparent capacity of CoHCC-PAN for Zn2+ and Eu3+ was determined and found to be 0.353 and 0.69 meq/g, respectively. The higher capacity for Eu3+ ions than that for Zn2+ ions is due to the higher electrostatic interaction strength of the higher charge ion with the surface. Freundlich and Langmiur adsorption isotherms were used to investigate solute (Zn2+ or Eu3+) exchange phenomenon at the liquid/solid interface. The results indicated that both Langmuir and Freundlich isotherms fit well for both Zn2+ and Eu3+. Sorption data have been also treated with the Dubinin-Radushkevich equation. The kinetics of Zn2+ or Eu3+ sorption on the composite seems to show that the reaction was proceed via two steps. The first one was fast and probably due to adsorption followed by a slow exchange reaction. In view of the data obtained on the effect of particle size and metal ion concentrations on the rate of exchange reaction, it is concluded that the mechanism for both ions was chemical control. Generally, it seems that there are two exchange sites chemically equivalent but present in pores of different sizes which lead to different degrees of dehydration of the ions sorbed on the two sites

  17. Pilot scale ion exchange column study for reducing radioactivity discharges to environment

    International Nuclear Information System (INIS)

    Kore, S.G.; Yadav, V.K.; Sonar, N.L.; Valsala, T.P.; Narayan, J.; Sharma, S.P.; Chattopadhyay, S.; Dani, U.; Vishwaraj, I.

    2013-01-01

    Low level liquid waste (LLW) is generated during operation of Tarapur Atomic Power Station (TAPS). Chemical co-precipitation is the treatment method used for decontamination of this waste with respect to radionuclide prior to discharge to environment. Further polishing of effluent from the treated LLW was planned using ion exchange column to reduce the discharges to the environment In view of this ion exchange column study was carried out in the laboratory using in-house prepared cobalt ferrocyanide (COFC) based composite resin. Based on the encouraging results obtained in the lab studies, pilot scale study was carried out in the plant. Decontamination factor (DF) of 14-15 was obtained with respect to Cs isotopes and overall DF of 2-5 was obtained with respect to gross beta activity. (author)

  18. Small Column Ion Exchange Analysis for Removal of Cesium from SRS Low Curie Salt Solutions Using Crystalline Silicotitanate (CST) Resin

    International Nuclear Information System (INIS)

    ALEMAN, SEBASTIAN

    2004-01-01

    Savannah River Technology Center (SRTC) researchers modeled ion exchange removal of cesium from dissolved salt waste solutions. The results assist in evaluating proposed configurations for an ion exchange process to remove residual cesium from low curie waste streams. A process for polishing (i.e., removing small amounts) of cesium may prove useful should supernate draining fail to meet the Low Curie Salt (LCS) target limit of 0.1 Ci of Cs-137 per gallon of salt solution. Cesium loading isotherms and column breakthrough curves for Low Curie dissolved salt solutions were computed to provide performance predictions for various column designs

  19. Application of pressurized ion exchange to separations of transplutonium elements

    International Nuclear Information System (INIS)

    Campbell, D.O.

    1980-01-01

    High-pressure ion exchange chromatography, used first for nucleic acid separations, was applied to the production of the heavier actinides, particularly the transcurium elements. Its use at the TRU plant is described. Future developments are considered briefly

  20. Overview of technologies to reprocess ion-exchange resins

    International Nuclear Information System (INIS)

    Gavrish, V.M.; Chernikova, N.P.; Ivanets, V.G.

    2010-01-01

    The article deals with overview of technologies for reprocessing of ion-exchange resins and determining the most optimal solutions for Ukraine. The technologies for cementations, thermal reprocessing, bituminization and deep decontamination are considered.

  1. Triple-membrane reduces need for ion exchange regeneration

    International Nuclear Information System (INIS)

    Valcour, H.

    1989-01-01

    Triple-membrane water treatment systems are comprised of ultrafiltration units for pretreatment, electrodialysis reversal primary demineralizers, reverse osmosis secondary demineralizers, portable ion exchange unit polishing demineralizers, and ultraviolet sterilizers. The triple-membrane process is designed to provide an unprecedented degree of pretreatment to maximize efficiency, durability and reliability of the reverse osmosis, whilst reducing the required regeneration frequency of the ion exchange demineralizer by one to two orders of magnitude. (author)

  2. A Simple Apparatus for Fast Ion Exchange Separations

    International Nuclear Information System (INIS)

    Samsahl, K.

    1964-09-01

    An apparatus suitable for very fast ion exchange group separations in radiochemistry has been elaborated. The apparatus which consists of a system of glass tubes with pistons driven by the same force, allows the exact adjustment of influent solutions to a long series of ion-exchange columns. The practical application of the apparatus to the simultaneous separation of six groups of trace elements in the neutron activation analysis of biological material is described

  3. Inorganic ion exchangers. Application to liquid effluent processing

    International Nuclear Information System (INIS)

    Dozol, M.

    1983-10-01

    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 [fr

  4. Isotherms of ion exchange on titanates of alkaline metals

    International Nuclear Information System (INIS)

    Fillina, L.P.; Belinskaya, F.A.

    1986-01-01

    Present article is devoted to isotherms of ion exchange on titanates of alkaline metals. Therefore, finely dispersed hydrated titanates of alkaline metals (lithium, sodium, potassium) with ion exchange properties are obtained by means of alkaline hydrolysis of titanium chloride at high ph rates. Sorption of cations from salts solution of Li 2 SO 4 , NaNO 3 , Ca(NO 3 ) 2 , AgNO 3 by titanates is studied.

  5. A Simple Apparatus for Fast Ion Exchange Separations

    Energy Technology Data Exchange (ETDEWEB)

    Samsahl, K

    1964-09-15

    An apparatus suitable for very fast ion exchange group separations in radiochemistry has been elaborated. The apparatus which consists of a system of glass tubes with pistons driven by the same force, allows the exact adjustment of influent solutions to a long series of ion-exchange columns. The practical application of the apparatus to the simultaneous separation of six groups of trace elements in the neutron activation analysis of biological material is described.

  6. Samarium ion exchanged montmorillonite for high temperature cumene cracking reaction

    International Nuclear Information System (INIS)

    Binitha, N.N.

    2009-01-01

    Full text: Nano material Montmorillonite clay is cation exchanged with samarium and its catalytic influence in cumene cracking reaction is investigated. Effect of exchange with sodium ions on further exchange with samarium ions is also noted. Acidity measurements are done using TPD of ammonia. The retention of basic structure is proved from FTIR spectra and XRD patterns. Elemental analysis result shows that samarium exchange has occurred, which is responsible for the higher catalytic activity. Surface area and pore volume remains more or less unaffected upon exchange. Thermogravimetric analysis indicates the enhanced thermal stability on exchanging. Cumene cracking reaction is carried out at atmospheric pressure in a fixed bed glass reactor at 673 K. The predominance of Bronsted acidity is confirmed from high selectivity to benzene. (author)

  7. Comparative study on bromide and iodide ion-isotopic exchange reactions using strongly basic anion exchange resin Duolite A-113

    International Nuclear Information System (INIS)

    Lokhande, R.S.; Dole, M.H.; Singare, P.U.

    2006-01-01

    Kinetics of ion-isotopic exchange reaction was studied using industrial grade ion exchange resin Duolite A-113. The radioactive isotopes 131 I and 82 Br were used to trace the ion-isotopic exchange reaction. The experiments were performed in the temperature range of 26.0degC to 43.0degC and the concentration of external ionic solution varying from 0.005 M to 0.100 M. For bromide ion-isotopic exchange reaction, the calculated values of specific reaction rate, initial rate of bromide ion exchange, and amount of bromide ions exchanged were obtained higher than that for iodide ion-isotopic exchange reaction under identical experimental conditions. The observed variation in the results for two ion-isotopic exchange reactions was due to the difference in the ionic size of bromide and iodide ions. (author)

  8. Conditioning of inorganic ion exchangers based on cerium (IV) antimonate in cement matrix. Vol. 3

    International Nuclear Information System (INIS)

    Aly, H.F.; Zakareia, N.; El-Dessouky, M.I.; Abo-Mosallem, N.M.; EL-Naggar, I.M.

    1996-01-01

    The use of inorganic adsorbents for treatment of aqueous radioactive waste has many advantages; namely; better resistance to chemical action, thermal stability, compatibility with immobilization matrices and resistance to radiation. Inorganic ion exchangers process many properties which make them more suitable for rad waste treatment than organic exchange resins. Inorganic ion exchange materials can be immobilized using cement matrix to obtain good solidified waste form. In this work, the removal of radioactive nuclides from radioactive waste is carried out by chemical in-situ precipitation. The addition of cerium (IV) antimonate (cesb) to cement mixture enhances the compressive strength more than plain cement. Waste package containing cesb increased the compressive strength relative to original ordinary portland cement (OPC) matrix for waste products immersed in tap water for one month. The compressive strength increases in the order; st Ce Sb> mix Ce Sb> Na Ce Sb> Co Ce Sb> Cs Ce Sb> OPC> Eu Ce Sb> Ce Sb; (mix refers to all the radionuclides used here). The cumulative leached fractions of 60 Co and 134 Cs decreased for solidified waste products containing Ce Sb in comparison to plain cement. 2 figs., 9 tabs

  9. Conditioning of inorganic ion exchangers based on cerium (IV) antimonate in cement matrix. Vol. 3

    Energy Technology Data Exchange (ETDEWEB)

    Aly, H F; Zakareia, N; El-Dessouky, M I; Abo-Mosallem, N M; EL-Naggar, I M [Hot Laboratory and Waste Management Centre, Atomic Energy Authority, P.O. Box 13759, Cairo (Egypt)

    1996-03-01

    The use of inorganic adsorbents for treatment of aqueous radioactive waste has many advantages; namely; better resistance to chemical action, thermal stability, compatibility with immobilization matrices and resistance to radiation. Inorganic ion exchangers process many properties which make them more suitable for rad waste treatment than organic exchange resins. Inorganic ion exchange materials can be immobilized using cement matrix to obtain good solidified waste form. In this work, the removal of radioactive nuclides from radioactive waste is carried out by chemical in-situ precipitation. The addition of cerium (IV) antimonate (cesb) to cement mixture enhances the compressive strength more than plain cement. Waste package containing cesb increased the compressive strength relative to original ordinary portland cement (OPC) matrix for waste products immersed in tap water for one month. The compressive strength increases in the order; st Ce Sb> mix Ce Sb> Na Ce Sb> Co Ce Sb> Cs Ce Sb> OPC> Eu Ce Sb> Ce Sb; (mix refers to all the radionuclides used here). The cumulative leached fractions of {sup 60} Co and {sup 134} Cs decreased for solidified waste products containing Ce Sb in comparison to plain cement. 2 figs., 9 tabs.

  10. Mixed matrix microporous hollow fibers with ion-exchange functionality

    NARCIS (Netherlands)

    Kiyono, R.; Kiyono, R.; Koops, G.H.; Wessling, Matthias; Strathmann, H.

    2004-01-01

    Heterogeneous hollow fiber membranes with cation exchange functionality are prepared using a wet spinning technique. The spinning dope solutions are prepared by dispersing finely ground cation ion-exchange resin (CER) particles in an N-methyl pyrrolidone solution of polysulfone (PSF). The polymer

  11. Isotope exchange of strontium and molybdate ions in strontium polymolybdates

    International Nuclear Information System (INIS)

    Atun, G.

    2002-01-01

    The heterogeneous isotopic exchange reactions in strontium polymolybdates of Sr 2+ and MoO 4 2- ions in the strontium nitrate and sodium molybdate solutions have been studied using 90 Sr and 99 Mo as tracers. Electrometric methods have been used to study the compositions of strontium molybdates obtained by adding strontium chloride to a progressively acidified solution of sodium molybdate. It has been found that the exchange fraction increases with increasing chain length of strontium polymolybdate. The exchange equilibrium constant (K ex ) has been calculated between 298 and 348 K as well as ΔG deg, ΔH deg and ΔS deg. The results indicate that Sr 2+ cations have a much higher affinity for exchangers than MoO 4 2- anions. By fitting the data to the Dubinin-Radushkevich (D-R) isotherm it has been shown that the exchange capacity (X m ) for both ions is affected by the ion adsorption process at low temperatures and by the ion exchange process at high temperatures. At high concentrations, the recrystallization process contributes to on the cation exchange but is ineffective on the anion exchange mechanism. (author)

  12. Isotopic exchange reaction between barium ion and tri barium phosphate

    International Nuclear Information System (INIS)

    Bilgin, G.B.; Cetin, I.

    1982-01-01

    Heterogeneous exchange reaction of tri barium phosphate in barium chloride solution has been studied using 133 Ba as a tracer. The results show that the exchange fraction increases as barium chloride concentration increases for different mole ratio of the exchange ion on the solid surface and in the solution. The phenomenon was studied with respect to the previous treatment of the precipitate leading to different crystal sizes and the effect of reaction time. (author)

  13. Ion-exchange concentration of inorganic anions from aqueous solution

    Directory of Open Access Journals (Sweden)

    L. P. Bondareva

    2016-01-01

    Full Text Available Monitoring of natural waters in the present time - consuming process, the accuracy of which is influenced by many factors: the composition of water, the presence of impurities and "interfering" components. The water sample preparation process includes the step of concentration and separation of ions determined. The most versatile, efficient, and frequently used method is the concentration of inorganic anions from aqueous solutions by ion exchanger, which can optimize the composition of water to the optimal for identification and quantitative determination of anions. The characteristics of sorption chloride, nitrate and sulfate ions of basic anion exchange resin AВ-17 and Purolite A430 were compared in the article. The constants of protolysis of ion exchangers both AB 17 and Purolite A430 are the same and equal 0.037 ± 0,002. The value of total capacity (POE Purolite A430 was 4.3 mmol/g, AB 17 – 3.4 mmol/g. The studied ion exchangers have the same type of ionic groups – quaternary ammonium, but their number and denotes differ. The number of quaternary ammonium groups is higher in Purolite A430, respectively the number of absorbed anions of these ion exchanger is higher. The values of dynamic exchange capacity (DOE of ion exchanger Purolite A430 is higher than these values of AB-17 and equal to 1.48 ± 0.03 mmol / dm3 for chloride ion, 1.50 ± 0.03 mmol / dm3 for nitrate ion, 1.62 ± 0.03 mmol / dm3 for sulfate ion. The values of the POE and DOE of anion-exchange resins Purolite A430 and AV-17 and the characteristics of the individual sorption of chloride, nitrate, sulfate ions showed an advantage of the Purolite for the concentrationing of anions. It is found that times of anions sorption from triple-anion solutions by Purolite A430 are significantly different for different anions, and these times are close for anion-exchanger AV-17. It proves the possibility of quantitative separation and concentration by anion-exchanger Purolite A430.

  14. Ion conductivities of ZrF4-BaF2-CsF glasses

    International Nuclear Information System (INIS)

    Kawamoto, Yoji; Nohara, Ichiro

    1987-01-01

    The glass-forming region in the ZrF 4 -BaF 2 -CsF glass system has been determined and the ac conductivity and the transport number of fluoride ions have been measured. The conductivities of compounds β-Cs 2 ZrF 6 , α-SrZrF 6 , α-BaZrF 6 , β-BaZrF 6 and α-PbZrF 6 have also been measured. These results and a previous study of ZrF 4 -BaF 2 -MF n (M: the groups I-IV metals) glasses revealed the following: (1) the ZrF 4 -BaF 2 -CsF glasses are exclusively fluoride-ion conductors; (2) the ionic conductivities of ZrF 4 -based glasses are predominantly determined by the activation energies for conduction; (3) the activation energy for conduction decreases with an increase in the average polarizability of glass-constituting cations; (4) a decrease in average Zr-F bond length and a lowering of the average F coordination number of Zr are presumed to increase the activation energy for conduction. Principles of developing ZrF 4 -based glasses with higher conductivities have also been proposed. (Auth.)

  15. Immobilization of ion exchange radioactive resins of the TRIGA Mark III nuclear reactor

    International Nuclear Information System (INIS)

    Garcia M, H.; Emeterio H, M.; Canizal S, C.

    1999-01-01

    This work has the objective to develop the process and to define the agglutinating material which allows the immobilization of the ion exchange radioactive resins coming from the TRIGA Mark III nuclear reactor contaminated with Ba-133, Co-60, Cs-137, Eu-152, and Mn-54 through the behavior analysis of different immobilization agents such as: bitumens, cement and polyester resin. According to the International Standardization the archetype samples were observed with the following tests: determination of free liquid, leaching, charge resistance, biodegradation, irradiation, thermal cycle, burned resistance. Generally all the tests were satisfactorily achieved, for each agent. Therefore, the polyester resin could be considered as the main immobilizing. (Author)

  16. Kinetics of solid-phase in ion exchange on tin hydrogen phosphate

    International Nuclear Information System (INIS)

    Kislitsyn, M.N.; Ketsko, V.A.; Yaroslavtsev, A.B.

    2004-01-01

    Solid state reactions in mixture of tin hydrogen phosphate and alkali metal (M=Na, K, Cs) chlorides have been studied both in the mode of polythermal heating and at a fixed temperature, using data of X-ray phase and thermogravimetric analyses. In the range 400-750 Deg C solid state ion exchange reactions occur in the systems studied and yield mono-- and dialkali phosphates MHSn(PO 4 ) 2 and M 2 Sn(PO 4 ) 2 . Counter diffusion coefficients for alkali metal cations and protons in the matrices of compositions MHSn(PO 4 ) 2 and M 2 Sn(PO 4 ) 2 have been determined [ru

  17. Synthesis and characterization of some inorganic ion exchange materials and its application in the treatment of hazardous waste

    International Nuclear Information System (INIS)

    El-Deeb, A.B.I.M.

    2008-01-01

    inorganic ion exchange materials play an important role in the last decays in the fields of industry, medicine, agriculture and nuclear technology due to their stabilities towards thermal and radiation and their resistance to chemical attack. the most important property of inorganic ion exchangers enabling their use in the various chemical separation is the selectivity. the selectivity behaviour of synthetic inorganic ion exchanges are still far from being clearly understood. this work had been done in an attempt to synthesize of inorganic ion exchangers such as zircon-titanate and doping alkali metals with zircon-titanate to produce a new developed ion exchanger with properties allow to used in the treatment of hazardous wastes. this work is concerned with the preparation of zircon-titanate and the doping of some alkali metals (K,Na,Li and Cs)with zircon-titanate. characterization of the synthesized ion exchangers using x-ray diffraction, x-ray fluorescence, infrared spectroscopy, surface area and thermal analysis were conducted. equilibrium measurements and effect of batch factor, ph of the medium on percent uptake were determined. capacity measurements and sorption isotherm studies were also investigated on zircon-titanate and its dopant products.

  18. Ion exchange of alkaline metals on the thin-layer zinc ferrocyanide

    International Nuclear Information System (INIS)

    Betenekov, N.D.; Buklanov, G.V.; Ipatova, E.G.; Korotkin, Yu.S.

    1991-01-01

    Basic regularities of interphase distribution in the system of thin-layer sorbent on the basis of mixed zinc ferrocyanide (FZ)-alkaline metal solution (Na, K, Rb, Cs, Fr) in the column chromatography made are studied. It is established that interphase distribution of microgram amounts of alkaline metals in the systems thin-layer FZ-NH 4 NO 3 electrolyte solutions is of ion-exchange character and subjected to of law effective mass. It is shown that FZ thin-layer material is applicable for effective chromatographic separation of alkaline metal trace amounts. An approach to the choice of a conditions of separate elution of Na, K, Rb, Cs, Fr in the column chromatography mode

  19. Ion exchange removal of technetium from salt solutions

    International Nuclear Information System (INIS)

    Walker, D.D.

    1983-01-01

    Ion exchange methods for removing technetium from waste salt solutions have been investigated by the Savannah River Laboratory (SRL). These experiments have shown: Commercially available anion exchange resins show high selectivity and capacity for technetium. In column runs, 150 column volumes of salt solution were passed through an ion exchange column before 50% 99 Tc breakthrough was reached. The technetium can be eluted from the resin with nitric acid. Reducing resins (containing borohydride) work well in simple hydroxide solutions, but not in simulated salt solutions. A mercarbide resin showed a very high selectivity for Tc, but did not work well in column operation

  20. Advanced ion exchange resins for PWR condensate polishing

    International Nuclear Information System (INIS)

    Hoffman, B.; Tsuzuki, S.

    2002-01-01

    The severe chemical and mechanical requirements of a pressurized water reactor (PWR) condensate polishing plant (CPP) present a major challenge to the design of ion exchange resins. This paper describes the development and initial operating experience of improved cation and anion exchange resins that were specifically designed to meet PWR CPP needs. Although this paper focuses specifically on the ion exchange resins and their role in plant performance, it is also recognized and acknowledged that excellent mechanical design and operation of the CPP system are equally essential to obtaining good results. (authors)

  1. Minimization of storage and disposal volumes by treatment of liquids by highly selective ion exchangers

    International Nuclear Information System (INIS)

    Tusa, E.; Harjula, R.; Lehto, J.

    2000-01-01

    Novel highly selective inorganic ion exchangers provide new efficient methods for the treatment of nuclear waste liquids. These methods have several advantages compared to conventional technologies such as evaporation, direct solidification or treatment by organic ion exchange resins. Due to high selectivity, the radionuclides can be concentrated to a very small volume even from high-salt effluents. This means that the volume waste will be very small compared to other methods, which brings considerable savings in the cost of intermediate storage and final disposal. Process equipment are highly compact and require little supervision, which brings down the capital and operation costs. The new selective inorganic ion exchangers CsTreat, SrTreat and CoTreat (manufactured by Fortum Engineering Ltd., Finland) have the highest selectivities and processing capacities, exceeding those of zeolites by several orders of magnitude. The materials are now in use in a number of nuclear sites worldwide, including those in the USA, Europe and Japan. Installations include mobile and stationary systems. Considerable experience has been gained in the use of these new materials. Lessons learned, as well as advantages and economic benefits of these highly selective exchangers will be discussed in this paper. (authors)

  2. Mechanism of ion exchange in zirconium phosphates. 17. Dehydration behavior of lithium ion exchanged phases

    Energy Technology Data Exchange (ETDEWEB)

    Clearfield, A; Pack, S P; Troup, J M [Ohio Univ., Athens (USA). Dept. of Chemistry

    1977-01-01

    The phases formed by the dehydration of lithium exchanged ..cap alpha..-zirconium phosphate, Zr(HP0/sub 4/).H/sub 2/0, were determined by a combination of X-ray, TGA and DTA studies. Samples containing 10, 20, 30 ..... 100% of theoretical lithium ion capacity were examined. The data are summarized in a phase diagram which however is not an equilibrium diagram because of the slowness of approach to equilibrium. The numerous phases obtained and the ease with which they rearrange indicates a high mobility for the incorporated cations. This suggested that ..cap alpha..-zirconium phosphate may behave as a solid electrolyte and indeed this was demonstrated by having it serve in that capacity in a small sodium sulfur battery.

  3. Enrichment of 15N by ion exchange chromatography

    International Nuclear Information System (INIS)

    Ohwaki, Masao; Ohtsuka, Haruhisa; Nomura, Masao; Okamoto, Makoto; Fujii, Yasuhiko

    1996-01-01

    15 N isotope separation was studied using cation exchange resins which consist of functional groups: sulfonic acid, carboxylic acid and phenol at various concentration of the eluent LiOH. The isotope separation coefficients for these ion exchange resins were observed to be nearly equal, in spite of the large difference in ion exchange characteristics. The effect of flow rate on 15 N isotope separation was also studied, and the results indicate that the operation at high flow rate would be preferable for the industrial process of 15 N enrichment. Based on the preliminary investigations, a continuous operation using a series of ion exchange columns has been carried out in order to achieve high enrichment of 15 N. (author)

  4. The Role of Ion Exchange Membranes in Membrane Capacitive Deionisation.

    Science.gov (United States)

    Hassanvand, Armineh; Wei, Kajia; Talebi, Sahar; Chen, George Q; Kentish, Sandra E

    2017-09-14

    Ion-exchange membranes (IEMs) are unique in combining the electrochemical properties of ion exchange resins and the permeability of a membrane. They are being used widely to treat industrial effluents, and in seawater and brackish water desalination. Membrane Capacitive Deionisation (MCDI) is an emerging, energy efficient technology for brackish water desalination in which these ion-exchange membranes act as selective gates allowing the transport of counter-ions toward carbon electrodes. This article provides a summary of recent developments in the preparation, characterization, and performance of ion exchange membranes in the MCDI field. In some parts of this review, the most relevant literature in the area of electrodialysis (ED) is also discussed to better elucidate the role of the ion exchange membranes. We conclude that more work is required to better define the desalination performance of the proposed novel materials and cell designs for MCDI in treating a wide range of feed waters. The extent of fouling, the development of cleaning strategies, and further techno-economic studies, will add value to this emerging technique.

  5. Formulation study on immobilization of spent ion exchange resins in polymer cement

    International Nuclear Information System (INIS)

    Xia Lili; Lin Meiqiong; Bao Liangjin; Fan Xianhua

    2006-01-01

    The aim of this study is to develop a formulation of cement-solidified spent radioactive ion exchange resin form. The solidified form consists of a sort of composite cement, epoxide resin emulsion, and spent ion exchange resins. The composite cement is made up of quick-setting sulphoaluminate cement, silica powder, zeolite, and fly ash in the proportion 1:0.05:0.10:0.05. Sixteen combinations of composite cement, epoxide resin emulsion and mixed anion-cation exchange resins are selected according to a three-factors-four-levels normal design table with the compression strength as the evaluation criterion. The resulted formulation is as follows: the mass ratio of polymer emulsion to composite cement is 0.55:1, the loading of mixed anion-cation exchange resins is 0.3, and the anionic-to-cationic exchange resins ratio is 2:1. The polymer cement solidified forms were tested after 28 d curing for Cs + and Sr 2+ leaching rates, pH and conductivity of the leaching water, and radiation-resistant property in addition to their compressive strength. The measurement results indicate that the performance of thus prepared solidified forms can meet the requirements of the National Standard GB14569.1-93 for near earth's surface disposal of low radioactive waste. (authors)

  6. Chromate ion-exchange study for cooling water

    International Nuclear Information System (INIS)

    Sengupta, A.K.

    1985-01-01

    In spite of high chromate selectivity, the ion-exchange process for Cr(IV) recovery from cooling tower blowdown is yet to be commercially popular. Possible degradation of the ion-exchange resin by the oxidative action of Cr(IV) during ion exchange has been considered as the prime obstacle. Resins have been manufactured with fairly acceptable properties to withstand both physical attrition and chemical oxidation. Demonstrated during the course of this research is early, gradual Cr(VI) breakthrough during fixed-bed column runs at acidic pH in the presence of competing sulfate and chloride anions. The advantage of high chromate selectivity is essentially lost due to the early Cr(VI) breakthrough because the column runs are always terminated after a pre-determined level of Cr(VI) has appeared in the treated water. Experimental results provide sufficient evidence that this is not due to poor column kinetics or electrolyte penetration. The chromate ion-exchange mechanism has been investigated in order to explain the foregoing anomalies for the chromate-exchange process. The knowledge of chromate ion-exchange mechanism has been used to overcome the shortcoming of gradual Cr(VI) breakthrough. This study shows that: (a) a continuous counter-current ion-exchange system theoretically offers much higher Cr(VI) removal capacity compared to conventional single-unit fixed-bed system for any pre-determined level of Cr(VI) breakthrough; (b) by modifying the resin composition, the gradual Cr(VI) breakthrough can be greatly eliminated

  7. THERMODYNAMICS OF ION-EXCHANGED NATURAL CLINOPTILOLITE

    Science.gov (United States)

    Natural clinoptilolite from Castle Creek, Idaho, and its cation-exchanged variants (Na-Cpt, NaK-Cpt, K-Cpt, and Ca-Cpt) were studied by high-temperature calorimetry. The hydration enthalpy for all clinoptilolites is about -30 kJ/mol H2O (liquid water reference state) at 25 C. T...

  8. Removal of Cs+, Sr2+, and Co2+ ions from the mixture of organics and suspended solids aqueous solutions by zeolites

    International Nuclear Information System (INIS)

    Fang, Xiang Hong; Fang, Fang; Lu, Chun Hai; Zheng, Lei

    2017-01-01

    Serving as an excellent adsorbent and inorganic ion exchanger in the water purification field, zeolite 4A has in this work presented a strong capability for purifying radioactive waste, such as Sr 2+ , Cs + , and Co 2+ in water. During the processes of decontamination and decommissioning of suspended solids and organics in low-level radioactive wastewater, the purification performance of zeolite 4A has been studied. Under ambient temperature and neutral condition, zeolite 4A absorbed simulated radionuclides such as Sr 2+ , Cs + , and Co 2+ with an absorption rate of almost 90%. Additionally, in alkaline condition, the adsorption percentage even approached 98.7%. After conducting research on suspended solids and organics of zeolite 4A for the treatment of radionuclides, it was found that the suspended clay was conducive to absorption, whereas the absorption of organics in solution was determined by the species of radionuclides and organics. Therefore, zeolite 4A has considerable potential in the treatment of radioactive wastewater

  9. Transient effects in SIMS analysis of Si with Cs sup + at high incidence angles Secondary ion yield variations

    CERN Document Server

    Heide, P A W

    2002-01-01

    Secondary ion mass spectrometry (SIMS) depth profile analysis of Si wafers using 1 keV Cs sup + primary ions at large incidence angles (80 deg. ) is plagued by unusually strong transient effects (variations in both sputter and ion yields). Analysis of a native oxide terminated Si wafer with and without the aid of an O sub 2 leak, and an Ar sup + pre-sputtered wafer revealed correlations between the implanted Cs content and various secondary ion intensities consistent with that expected from a resonance charge transfer process (that assumed by the electron tunneling model). Cs concentrations were defined through X-ray photoelectron spectroscopy of the sputtered surface from SIMS profiles terminated within the transient region. These scaled with the surface roughening occurring under these conditions and can be explained as resulting from the associated drop in sputter rates. An O induced transient effect from the native oxide was also identified. Characterization of these effects allowed the reconstruction of ...

  10. Minor Actinide Separations Using Ion Exchangers Or Ionic Liquids

    International Nuclear Information System (INIS)

    Hobbs, D.; Visser, A.; Bridges, N.

    2011-01-01

    This project seeks to determine if (1) inorganic-based ion exchange materials or (2) electrochemical methods in ionic liquids can be exploited to provide effective Am and Cm separations. Specifically, we seek to understand the fundamental structural and chemical factors responsible for the selectivity of inorganic-based ion-exchange materials for actinide and lanthanide ions. Furthermore, we seek to determine whether ionic liquids can serve as the electrolyte that would enable formation of higher oxidation states of Am and other actinides. Experiments indicated that pH, presence of complexants and Am oxidation state exhibit significant influence on the uptake of actinides and lanthanides by layered sodium titanate and hybrid zirconium and tin phosphonate ion exchangers. The affinity of the ion exchangers increased with increasing pH. Greater selectivity among Ln(III) ions with sodium titanate materials occurs at a pH close to the isoelectric potential of the ion exchanger. The addition of DTPA decreased uptake of Am and Ln, whereas the addition of TPEN generally increases uptake of Am and Ln ions by sodium titanate. Testing confirmed two different methods for producing Am(IV) by oxidation of Am(III) in ionic liquids (ILs). Experimental results suggest that the unique coordination environment of ionic liquids inhibits the direct electrochemical oxidation of Am(III). The non-coordinating environment increases the oxidation potential to a higher value, while making it difficult to remove the inner coordination of water. Both confirmed cases of Am(IV) were from the in-situ formation of strong chemical oxidizers.

  11. Radiocarbon detection by ion charge exchange mass spectrometry

    International Nuclear Information System (INIS)

    Hotchkis, Michael; Wei, Tao

    2007-01-01

    A method for detection of radiocarbon at low levels is described and the results of tests are presented. We refer to this method as ion charge exchange mass spectrometry (ICE-MS). The ICE-MS instrument is a two stage mass spectrometer. In the first stage, molecular interferences which would otherwise affect radiocarbon detection at mass 14 are eliminated by producing high charge state ions directly in the ion source (charge state ≥2). 14 N interference is eliminated in the second stage by converting the beam to negative ions in a charge exchange cell. The beam is mass-analysed at each stage. We have built a test apparatus consisting of an electron cyclotron resonance ion source and a pair of analysing magnets with a charge exchange cell in between, followed by an electrostatic analyser to improve the signal to background ratio. With this apparatus we have measured charge exchange probabilities for (C n+ → C - ) from 4.5 to 40.5 keV (n = 1-3). We have studied the sources of background including assessment of limits for nitrogen interference by searching for negative ions from charge exchange of 14 N ions. Our system has been used to detect 14 C in enriched samples of CO 2 gas with 14 C/ 12 C isotopic ratio down to the 10 -9 level. Combined with a measured sample consumption rate of 4 ng/s, this corresponds to a capability to detect transient signals containing only a few μBq of 14 C activity, such as may be obtained from chromatographic separation. The method will require further development to match the sensitivity of AMS with a gas ion source; however, even in its present state its sensitivity is well suited to tracer studies in biomedical research and drug development

  12. Cesium removal flow studies using ion exchange

    International Nuclear Information System (INIS)

    Lee, D.D.; Walker, J.F. Jr.; Taylor, P.A.

    1997-01-01

    Cesium and strontium radionuclides are a small fraction of the mainly sodium and potassium salts in underground storage tank supernatant at US Department of Energy (DOE) sites at Hanford, Oak Ridge, Savannah River, and Idaho that DOE must remediate. Cesium-137 ( 137 Cs) is the primary gamma radiation source in the dissolved tank waste at these sites, and its removal from the supernatant can reduce the hazard and waste classification of the treated waste reducing the further treatment and disposal costs. Several cesium removal sorbents have been developed by private industry and the US DOE's Office of Science and Technology. Several of these removal technologies have been previously tested in small batch and column tests using simulated and a few actual supernatant under DOE's Environmental Management (EM) programs including the Tanks Focus Area (TFA) and the Efficient Separations and Processing (ESP) Cross-Cutting Program

  13. Design of fixed-bed ion exchange columns for wastewater treatment

    International Nuclear Information System (INIS)

    Robinson, S.M.; Arnold, W.D.; Byers, C.H.

    1990-01-01

    Oak Ridge National Laboratory plans to use chabazite zeolites for decontamination of process wastewater which contains ppb levels of Sr-90 and Cs-137. Treatability studies have indicated that chabazite zeolites have high selectivities and loadings for removal of trace amounts of Cs-137 and Sr-90 from wastewater containing high concentrations of calcium and magnesium. These studies also indicated that the efficiency of the zeolite system is dependent on the column design and operating conditions. Results from 20-mL, 566-L, and 3,760-L column tests indicated that the optimized design of full-scale columns could halve the generation rate of loaded zeolite. The corresponding annual waste disposal costs for loaded zeolite generated at the ORNL plant varied from $80,000 to $170,000 based on the present disposal charges of $1400/m 3 indicating that design of zeolite ion exchange systems for minimization of secondary waste is imperative. This report summarizes the results of study to model multicomponent ion-exchange columns. 7 refs., 10 figs., 5 tabs

  14. Design of fixed-bed ion exchange columns for wastewater treatment

    International Nuclear Information System (INIS)

    Robinson, S.M.; Arnold, W.D.; Byers, C.H.

    1990-01-01

    Oak Ridge National Laboratory plans to use chabazite zeolites for decontamination of process wastewater which contains ppb levels of Sr-90 and Cs-137. Treatability studies have indicated that chabazite zeolites have high selectivities and loadings for removal of trace amounts of Cs-137 and Sr-90 from wastewater containing high concentrations of calcium and magnesium. These studies also indicated that the efficiency of the zeolite system is dependent on the column design and operating conditions. Results from 20-mL, 566-L, and 3,760-L column tests indicated that the optimized design of full-scale columns could halve the generation rate of loaded zeolite. The corresponding annual waste disposal costs for loaded zeolite generated at the ORNL plant varied from $80,000 to $170,000 based on the present disposal charges of $1400/m 3 indicating that design of zeolite ion exchange systems for minimization of secondary waste is imperative. This report summarizes the results of a study to model multicomponent ion-exchange columns. 7 refs., 10 figs., 5 tabs

  15. Potential curves and spectroscopic study of the electronic states of the molecular ion LiCs+

    International Nuclear Information System (INIS)

    Moughrabi, A.; Korek, M.; Allouche, A.R.

    2004-01-01

    Full text.Due to a very accurate high-resolution techniques and to the spectacular developments in ultracold alkali atom trapping developments which are at the root of photo association spectroscopy there has been a renewed interest on the spectroscopic study of alkali dimers. The existence of new experimental data on these species has stimulated theoretical approaches, necessary to provide predictions accurate enough to be useful for interpretation and evenly for guidance of experiments. With the aim of improving the accuracy of predictions we will perform a theoretical study of the electronic structure of the molecular ion LiCs + , using a method mainly in the way by which core-valence effects are taken into account. To investigate the electronic structure of LiCs + we will use the package CIPSI (Configuration Interaction by Perturbation of a multiconfiguration wave function Selected Interactively) of the Laboratoire de Physique Quantique (Toulouse, France). The atoms Li and Cs will be treated through non-empirical effective one electron core potentials of Durand and Barthelat type. Molecular orbitals for LiCs + will be derived from Self Consistent Field Calculations (SCF) and full valence Configuration Interaction (IC) calculations. A core-core interaction more elaborated than the usual approximation 1/R will be taken into account as the sum of an exponential repulsive term plus a long range dispersion term approximated by the well known London formula. Potential energy calculations will be performed for different molecular states, for numerous values of the inter-nuclear distance R in a wide range. Spectroscopic constants have been derived for the bound states with a regular shape A ro vibrational study have been performed for the ground states with a calculation of the rotational and centrifugal distortion constants. A calculation for the transition dipole moment and matrix elements have been done for the bound states

  16. The use of fibrous ion exchangers in gold hydrometallurgy

    Science.gov (United States)

    Kautzmann, R. M.; Sampaio, C. H.; Cortina, J. L.; Soldatov, V.; Shunkevich, A.

    2002-10-01

    This article examines a family of ion-exchange fibers, FIBAN, containing primary and secondary amine groups. These ion exchangers have a fiber diameter of 20 40 Μm, high osmotic and mechanic stability, a high rate of adsorption and regeneration, and excellent dynamic characteristics as filtering media. Inparticular, this article discusses the use of FIBAN fibrous ion exchangers in the recovery of gold cyanide andbase-metal cyanides (copper and mercury) from mineral-leaching solutions. The influence of polymer structure and water content on their extraction ability is described, along with key parameters of gold hydrometallurgy such as extraction efficiency, selectivity, pH dependence, gold cyanide loading, kinetics, and stripping.

  17. Evaluation of electrochemical ion exchange for cesium elution

    International Nuclear Information System (INIS)

    Bontha, J.D.; Kurath, D.E.; Surma, J.E.; Buehler, M.F.

    1996-04-01

    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

  18. Ion exchange in the 1980's in South Africa

    International Nuclear Information System (INIS)

    Giddey, T.B.S.

    1981-01-01

    In South Africa ion exchange plants have been modified into very sophisticated plants. This article looks at the development of- and application of resins and their manufacturing. At first it looks into how the equipment side has developed and changed in the last twenty years. High purity water production, desalination, waste water treatment and other applications of ion exchange in mineral recovery, like uranium, gold and base metals, and in chemical areas, like sugar processing, catalysis, tartaric acid and soda ash, are also discussed. Klipfontein Organic Products is setting up a plant to manufacture the whole range of ion exchange resins and thus to make SA needs to be independent of overseas suppliers of resin

  19. Modality analysis of anchored ion exchange tower using Ansys

    International Nuclear Information System (INIS)

    Li Liang; Lei Zeyong

    2008-01-01

    Ion exchange towers are exposed to serious damage in the event of earthquakes. It is very necessary to study the seismic resistance of ion exchange tower. A finite element model of anchored ion exchange tower was made by Ansys. The first 10 ranks of inherent frequencies were made out, and three-dimensional main vibratory model figures were drawn out. The maximal stress along x-axis and y-axis and the main displacement were found at the bottom part of the wall of tower junction with the pillars. It is concluded that the breakage of tower wall easily occurs at the bottom part of the wall of tower junction with the pillars. Therefore, it is very important to reinforce the junction of the tower body, and the strengthening plate should lie near the bottom of wall. (authors)

  20. Structural transitions, ion mobility, and conductivity in CsSbF3(H2PO4)

    Science.gov (United States)

    Kavun, V. Ya.; Uvarov, N. F.; Slobodyuk, A. B.; Ulihin, A. S.; Kovaleva, E. V.; Zemnukhova, L. A.

    2018-02-01

    Structural transitions, ion mobility, and conductivity in CsSbF3(H2PO4) (I) have been investigated by the methods of 1H, 19F, 31P NMR (including 1H, 19F, 31P MAS NMR), DSC, X-ray diffraction, and impedance spectroscopy. It was found that the fundamental changes in 1H, 19F, 31P NMR spectra (above 390 K) were associated with the formation of a crystalline disorder phase I with high ionic mobility in the proton and fluoride sublattices, as a result of a phase transition in the 400-420 K range. In the same temperature range, the transition of PO2(OH)2- anions from the "rigid lattice" to fast reorientations takes place. Above 430 K, there occurs a transition from the crystalline disordered phase to the amorphous one. The types of ion mobility in CsSbF3(H2PO4) and its amorphous phase have been established and temperature ranges of their realization have been determined (150-450 K). According to the NMR data, the diffusion in the proton sublattice of the disordered crystalline and amorphous phases is preserved even at room temperature. The ionic conductivity in CsSbF3(H2PO4) reaches the values of 2.6 × 10-4 S/cm in the temperature range 410-425 K and decreases down to 2.0 × 10-5 S/cm upon transition to the amorphous phase (435-445 K).

  1. Operating experience with a high-current Cs+1 injector for heavy-ion fusion

    International Nuclear Information System (INIS)

    Chupp, W.; Faltens, A.; Herrmannsfeldt, W.

    1981-03-01

    The construction and assembly of a Cs ion injector consisting of a pulsed source and 3 pulsed drift tubes has been complete since April 1980. The measurement program, underway since then to characterize the beam, has been interspersed with the development of diagnostic equipment. The Cs contact ionization source and each of the 3 drift tubes are driven by 500 kV Marx generators. The injector has been operated reliably at 300 kV/stage at a repetition rate of 1 pulse/4 sec. About 10 5 pulses have been accumulated. The space charge limited diode and drift tube acceleration system were designed with the aid of the EGUN code of Herrmannsfeldt. Measurements of the beam envelope have been made by means of a movable biased charge collector. Good agreement with the EGUN calculation is found. Measurements of the beam emittance have been made at the exit of the third drift tube. The normalized emittance π epsilon N = 2 x 10 -6 π m-rad is of better optical quality than that required for further acceleration and transport in a Heavy Ion Fusion (HIF) Induction Linac Driver

  2. Behavior study of spend ion exchange resins immobilized in pyrolyzed polymer matrix

    International Nuclear Information System (INIS)

    Ramos, P.B; Fuentes, N.O; Luca, V.

    2012-01-01

    The pyrolysis of spent ion exchange resins contained in epoxy resins represents an attractive alternative to cementation as a confining method. In this sense, a significant reduction of volume can be achieved, as well as avoiding the dispersion of the exhausted ion exchange resin by the means of an epoxy resin used as a matrix, while potentially limiting the release of highly radioactive long life isotopes such us Cs-137, Sr-90 and Co-60 among others. Three types of monoliths were made: (i) epoxy resin, (ii) epoxy resin with carbon and (iii) a binder of epoxy resin and clay. In every case, the monolith contained the ion exchange resin. They were prepared by the mixing of resin pearl loaded with epoxy cations and a subsequent pyrolysis process with a temperature increase ratio of 2 o C /min reaching maximum values in the range between 200 o C - 800 o C, remaining in it for 1 hour. Monoliths obtained for each final temperature had been characterized to obtain data corresponding to the mass loss, volume reduction and lixiviation, as well as mechanical and microstructural properties (author)

  3. Treatment of low-activity-level process wastewaters by continuous countercurrent ion exchange

    International Nuclear Information System (INIS)

    Hall, R.; Watson, J.S.; Robinson, S.M.

    1990-01-01

    A mobile pilot-scale continuous countercurrent ion-exchange (CCIX) system is being operated at the Oak Ridge National Laboratory (ORNL) for the treatment of wastewaters that contain predominantly calcium sodium, and magnesium bicarbonates and are slightly contaminated with 90 Sr and 137 Cs radioisotopes. A demonstration study is being conducted to evaluate the near-steady-state performance and feasibility of a pilot-scale CCIX column for the selective removal of strontium from wastewater. Test results show that the process removes strontium sufficiently from the wastewater to permit discharge while significantly reducing the volume of secondary waste generation. CCIX has the potential for effective use in several applications; however, it has not been frequently utilized by industries to date. The CCIX system could offer an economical alternative for decontamination of wastewaters containing trace amounts of contaminants prior to discharge into the environment. This paper discusses (a) application of the Thomas model for predicting breakthrough curves from ion exchange column tests, (b) methods for scaleup of experimental small-scale ion-exchange columns to industrial-scale columns, and (c) methods for predicting effluent compositions in a CCIX system. 20 refs., 6 figs., 2 tabs

  4. Recovery of boric acid from ion exchangers

    International Nuclear Information System (INIS)

    Pollock, C.W.

    1976-01-01

    The recovery of boric acid from an anion exchange resin is improved by eluting the boric acid with an aqueous solution of ammonium bicarbonate. The boric acid can be readily purified and concentrated by distilling off the water and ammonium bicarbonate. This process is especially useful for the recovery of boric acid containing a high percentage of 10 B which may be found in some nuclear reactor coolant solutions. 10 claims

  5. Ultrafiltration Membrane Fouling and the Effect of Ion Exchange Resins

    KAUST Repository

    Jamaly, Sanaa

    2011-12-01

    Membrane fouling is a challenging process for the ultrafiltration membrane during wastewater treatment. This research paper determines the organic character of foulants of different kinds of wastewater before and after adding some ion exchange resins. Two advanced organic characterization methods are compared in terms of concentration of dissolved organic carbons: The liquid chromatography with organic carbon (LC-OCD) and Shimadzu total organic carbon (TOC). In this study, two secondary wastewater effluents were treated using ultrafiltration membrane. To reduce fouling, pretreatment using some adsorbents were used in the study. Six ion exchange resins out of twenty were chosen to compare the effect of adsorbents on fouling membrane. Based on the percent of dissolved organic carbon’s removal, three adsorbents were determined to be the most efficient (DOWEX Marathon 11 anion exchange resin, DOWEX Optipore SD2 polymeric adsorbent, and DOWEX PSR2 anion exchange), and three other ones were determined to the least efficient (DOWEX Marathon A2 anion exchange resin, DOWEX SAR anion exchange resin, and DOWEX Optipore L493 polymeric adsorbent). Organic characterization for feed, permeate, and backwash samples were tested using LC-OCD and TOC to better understand the characteristics of foulants to prevent ultrafiltration membrane fouling. The results suggested that the polymeric ion exchange resin, DOWEX SD2, reduced fouling potential for both treated wastewaters. All the six ion exchange resins removed more humic fraction than other organic fractions in different percent, so this fraction is not the main for cause for UF membrane fouling. The fouling of colloids was tested before and after adding calcium. There is a severe fouling after adding Ca2+ to effluent colloids.

  6. Ionization and charge exchange in atom collision with multicharged ion

    International Nuclear Information System (INIS)

    Presnyakov, L.P.; Uskov, D.B.

    1984-01-01

    Single-electron ionization and charge exchange are considered in collisions of an atom with an ion of charge Z> or =3 and at velocities v>Z -1 /sup // 3 . The approach is based on the Keldysh quasiclassical method. The ionization and charge exchange processes are described within the framework of a single formalism. Effects of rotation and translation are taken into account. The calculated total and partial cross sections agree well with the available experimental data. OFF

  7. On the mechanism of ion exchange in zirconium phosphates

    International Nuclear Information System (INIS)

    Clearfield, A.; Kalnins, J.M.

    1978-01-01

    The exchange of transition metal (M 2+ ) ions from manganese through cobalt, nickel, copper to zinc with γ-zirconium phosphate was examined. By using acetate salts the hydrogen ion concentration is kept low enough to achieve high loadings. The fully loaded solids have the composition ZrM(PO 4 ) 2 .4H 2 O. Near quantitative uptakes are achieved at 100 0 C. The interlayer spacings change very little with loading indicating that γ-zirconium phosphate is able to accommodate cations and water molecules without appreciable increase in volume. The copper exchanged phase readily forms an acetylacetonate when shaken with 2,4-pentanedione. (author)

  8. Bench-Scale Studies with Argentine Ion Exchange Material

    International Nuclear Information System (INIS)

    Cicero-Herman, C.A.

    2002-01-01

    The United States Department of Energy (DOE), as well as international atomic energy commission, facilities use ion exchange materials for purification of aqueous streams in the nuclear industry. Unfortunately, the use of the ion exchange materials creates a waste stream that can be very high in both organic and radioactive constituents. Therefore, disposal of the spent resins often becomes an economic problem because of the large volumes of resin produced and the relatively few technologies that are capable of economically stabilizing this waste. Vitrification of this waste stream presents a reasonable disposable alternative because of its inherent destruction capabilities, the volume reductions obtainable, and the durable product that it produces

  9. Rupture loop annex ion exchange RLAIX vault deactivation

    Energy Technology Data Exchange (ETDEWEB)

    Ham, J.E.; Harris, D.L., Westinghouse Hanford

    1996-08-01

    This engineering report documents the deactivation, stabilization and final conditions of the Rupture Loop Annex Ion Exchange (RLAIX) Vault located northwest of the 309 Building`s Plutonium Recycle Test Reactor (PRTR). Twelve ion exchange columns, piping debris, and column liquid were removed from the vault, packaged and shipped for disposal. The vault walls and floor were decontaminated, and portions of the vault were painted to fix loose contamination. Process piping and drains were plugged, and the cover blocks and rain cover were installed. Upon closure,the vault was empty, stabilized, isolated.

  10. A summary of methods for conditioning and immobilizing ion-exchange resins

    International Nuclear Information System (INIS)

    Speranzini, R.A.; Buckley, L.P.

    1983-02-01

    Ion-exchange resins are used in CANDU-PHW nuclear power stations to purify heavy water in the primary heat transport (PHT) and moderator systems. Two promising techniques for conditioning spent ion-exchange resins for disposal have been evaluated: direct immobilization and incineration combined with immobilization of the ash and scrubbed off-gases. When ion-exchange resins were immobilized directly, volumes of bitumen products were about 0.75 times the volumes of untreated resin, while the volumes of cement and polyester products were 2 to 3 times larger. While incinerating the resin is an extra processing step, much smaller volumes result from the latter option. Bitumen and glass product volumes were six and ten times smaller, respectively, than the volumes of untreated resin, while cement and polyester product volumes were about one-half the volume of untreated resin. Since the releases of Cs-136 by leaching were lowest for products made by immobilization in glass, PHT resins which have high concentrations of Cs-137 should be vitrified. Moderator resins which have high concentrations of C-14 should be incinerated and the ash and C-14-contaminated scrubbing solutions should be immobilized. By pretreating such resins with calcium chloride or carbon dioxide, the C-14 present on resin could be released at temperatures below the ignition temperature of the resin. The pretreatment technique reduces the amount of inactive carbon dioxide that must be scrubbed to trap the C-14. The releases of C-14 from immobilized barium hydroxide scrubbing solution were the same as releases from immobilized resin

  11. Synthesis and characterization of tin(IV) antimonate and study of its ion-exchange equilibria

    International Nuclear Information System (INIS)

    Burham, N.; Abdel-Halim, S.H.; El-Shahat, M.F.

    1995-01-01

    Tin(IV) antimonate with different Sb/Sn molar ratios has been prepared. The characterization of the product materials was carried out using X-ray diffraction pattern, thermal analysis and infrared spectra. The saturation capacities of sodium and cesium were found to increase with Sb/Sn molar ratios. The K d values on thermal treatment of tin(IV) antimonate, as a cation exchanger, have been measured for some heavy metal ions in the temperature range of 50-400 deg C. The maximum adsorption of 10 -4 M of the metal ions studied was obtained at 400 deg C. The selectivity sequence was Eu 3+ > Co 2+ > Sr 2+ > Cs + for the sample heated up to 400 deg C. No adsorption was observed on the sample heated at 700 deg C because of the formation of SnO 2 and Sb 6 O 13 . (author) 9 refs.; 7 figs.; 5 tabs

  12. Specific ion effects on membrane potential and the permselectivity of ion exchange membranes.

    Science.gov (United States)

    Geise, Geoffrey M; Cassady, Harrison J; Paul, Donald R; Logan, Bruce E; Hickner, Michael A

    2014-10-21

    Membrane potential and permselectivity are critical parameters for a variety of electrochemically-driven separation and energy technologies. An electric potential is developed when a membrane separates electrolyte solutions of different concentrations, and a permselective membrane allows specific species to be transported while restricting the passage of other species. Ion exchange membranes are commonly used in applications that require advanced ionic electrolytes and span technologies such as alkaline batteries to ammonium bicarbonate reverse electrodialysis, but membranes are often only characterized in sodium chloride solutions. Our goal in this work was to better understand membrane behaviour in aqueous ammonium bicarbonate, which is of interest for closed-loop energy generation processes. Here we characterized the permselectivity of four commercial ion exchange membranes in aqueous solutions of sodium chloride, ammonium chloride, sodium bicarbonate, and ammonium bicarbonate. This stepwise approach, using four different ions in aqueous solution, was used to better understand how these specific ions affect ion transport in ion exchange membranes. Characterization of cation and anion exchange membrane permselectivity, using these ions, is discussed from the perspective of the difference in the physical chemistry of the hydrated ions, along with an accompanying re-derivation and examination of the basic equations that describe membrane potential. In general, permselectivity was highest in sodium chloride and lowest in ammonium bicarbonate solutions, and the nature of both the counter- and co-ions appeared to influence measured permselectivity. The counter-ion type influences the binding affinity between counter-ions and polymer fixed charge groups, and higher binding affinity between fixed charge sites and counter-ions within the membrane decreases the effective membrane charge density. As a result permselectivity decreases. The charge density and polarizability

  13. Specific ion effects on membrane potential and the permselectivity of ion exchange membranes

    KAUST Repository

    Geise, Geoffrey M.

    2014-08-26

    © the Partner Organisations 2014. Membrane potential and permselectivity are critical parameters for a variety of electrochemically-driven separation and energy technologies. An electric potential is developed when a membrane separates electrolyte solutions of different concentrations, and a permselective membrane allows specific species to be transported while restricting the passage of other species. Ion exchange membranes are commonly used in applications that require advanced ionic electrolytes and span technologies such as alkaline batteries to ammonium bicarbonate reverse electrodialysis, but membranes are often only characterized in sodium chloride solutions. Our goal in this work was to better understand membrane behaviour in aqueous ammonium bicarbonate, which is of interest for closed-loop energy generation processes. Here we characterized the permselectivity of four commercial ion exchange membranes in aqueous solutions of sodium chloride, ammonium chloride, sodium bicarbonate, and ammonium bicarbonate. This stepwise approach, using four different ions in aqueous solution, was used to better understand how these specific ions affect ion transport in ion exchange membranes. Characterization of cation and anion exchange membrane permselectivity, using these ions, is discussed from the perspective of the difference in the physical chemistry of the hydrated ions, along with an accompanying re-derivation and examination of the basic equations that describe membrane potential. In general, permselectivity was highest in sodium chloride and lowest in ammonium bicarbonate solutions, and the nature of both the counter- and co-ions appeared to influence measured permselectivity. The counter-ion type influences the binding affinity between counter-ions and polymer fixed charge groups, and higher binding affinity between fixed charge sites and counter-ions within the membrane decreases the effective membrane charge density. As a result permselectivity decreases. The

  14. Ion exchange and liquid column chromatography

    International Nuclear Information System (INIS)

    Walton, H.F.

    1980-01-01

    Major accomplishments in liquid chromatography for the past two years and reported in journals available to December 31, 1979 are reviewed. Emphasis has been placed on principles and methodology with some representative examples of application included. Applications are illustrated in two rather lenghtly tables, one covering inorganic ions and the other covering organic compounds. 544 references, 8 books, and 15 reviews are listed in the bibliography

  15. On the mechanism of ion exchange in zirconium phosphates

    International Nuclear Information System (INIS)

    Clearfield, A.; Frianeza, T.N.

    1978-01-01

    α-titanium phosphate, Ti(HPO 4 ) 2 .H 2 O, was found to form two sodium ion exchanged phases. A half exchanged phase of ideal composition TiNaH(PO 4 ) 2 .4H 2 O formed first. However, before all of the titanium phosphate was converted to this phase a second phase of higher Na + content formed. Thus, a three phase solid existed until sufficient sodium ion uptake (approximately 5.5 meq/g) produced only the two exchanged phases. Finally, the half exchanged phase was converted to the more highly loaded one and this latter phase existed from 6 to 8 meq/g of Na + uptake. Severe disordering of the crystal lattice during exchange is proposed to explain this unusual exchange behavior. A broad range of titanium phosphate-zirconium phosphate solid solutions was found to form. Their behavior towards Na + -H + exchange was determined and interpreted on the basis of the known behavior of the pure phases. Mixed Ti-Zr solid solutions of their pyrophosphates were obtained at elevated temperatures. (author)

  16. Estimation of Sputtering Damages on a Magnetron H- Ion Source Induced by Cs+ and H+ Ions

    CERN Document Server

    Pereira, H; Alessi, J; Kalvas, t

    2013-01-01

    An H− ion source is being developed for CERN’s Linac4 accelerator. A beam current requirement of 80 mA and a reliability above 99% during 1 year with 3 month uninterrupted operation periods are mandatory. To design a low-maintenance long life-time source, it is important to investigate and understand the wear mechanisms. A cesiated plasma discharge ion source, such as the BNL magnetron source, is a good candidate for the Linac4 ion source. However, in the magnetron source operated at BNL, the removal of material from the molybdenum cathode and the stainless steel anode cover plate surfaces is visible after extended operation periods. The observed sputtering traces are shown to result from cesium vapors and hydrogen gas ionized in the extraction region and subsequently accelerated by the extraction field. This paper presents a quantitative estimate of the ionization of cesium and hydrogen by the electron and H− beams in the extraction region of BNL’s magnetron ion source. The respective contributions o...

  17. Ion exchange filter transition plan for BWRs and PWRs

    International Nuclear Information System (INIS)

    Garcia, Susan; McElrath, Joel; Varnam, Jeremie; Giannelli, Joseph F.

    2014-01-01

    Analysis and quantification of reactor water, feedwater, and chemical and volume control system (CVCS) soluble metals and radioisotopes are essential for monitoring species that impact fuel performance, steam generator and heat exchanger performance, mitigation of stress corrosion cracking of reactor piping and internals, radiation fields and ensuring that dose mitigation techniques are effective. Soluble species in the CVCS, feedwater, reactor water and other process sample streams are usually collected on ion exchange membranes after the sample has passed through a 0.45 or 0.1 μm membrane filter. Cationic species are predominantly of interest. Most nuclear plants currently use cation exchange membranes from Toray Industries, Inc. In September 2012, it was reported that Toray Industries, Inc. would discontinue the manufacturing of cation exchange membranes at the end of 2012. Similar reports were received concerning ion exchange membranes manufactured by Pall Corporation. These reports prompted several plants and utilities to begin evaluating other products from various vendors to replace their current ion exchange membranes in preparation for a transition. With this possible change having a potential impact on the water chemistry analyses that are important for monitoring fuel reliability and corrosion and dose control, an initial scoping evaluation of ion exchange membrane availability from various vendor and plant experiences was conducted. Recommended approaches were provided to close identified gaps and reduce burden on nuclear plant chemistry laboratories. Additional work required in 2014, includes an independent laboratory review of membrane performance and in-plant demonstrations. These demonstrations and evaluations will assist the industry by providing the technical input needed to manage a change in membrane use so that preferred processes and media can be identified to minimize any adverse impacts on chemistry analyses that support chemistry control

  18. Study of the retention of radionuclides by ion-exchange resins contained in the circuits of a Pressurized Water Reactor

    International Nuclear Information System (INIS)

    Gressier, F.

    2008-11-01

    Physico-chemical quality of fluids in nuclear power plant circuits must be maintained in order to limit contamination and dose rate especially when the shutdown takes place. Nevertheless, an optimum between diminishing liquid waste and limiting solid waste production has to be reached, but at affordable costs. Ion-exchange resins of purification circuits are used to fulfill this goal. In this work, different resin types have been characterized (exchange capacity, water and electrolyte sorption) and their selectivity towards Co 2+ , Ni 2+ , Cs + and Li + cations have been studied. We have shown that the two cation-exchange resins selectivity varies according to the nature and concentrations of their counter-ions. Moreover, flow rate (and thus hydro-kinetics) impact on species retention in a column has been characterized: the more the flow rate, the more the ionic leakage (output concentration divided by input concentration) is fast and the more the output concentration front is spread. A literature revue has enabled to put in light advantages and drawbacks of the models of interest to simulate operations of ion-exchange resins. Thus, the pure end-members mixing model associated to a non-ideality description of the resin phase based on the regular solutions model has been retained for modelling ion-exchange equilibrium. Ion-exchange kinetics has been described by mass transfer coefficients. Using the experimental results to determine model parameters, these last ones have been implemented in a speciation code CHESS, coupled with a hydrodynamic code in HYTEC. On the one hand, equilibrium experiments of ion retention have been simulated and, on the other hand, column retention tests have been modelled. Finally, selectivity variations and hydro-kinetics impacts have been simulated on some test cases so as to demonstrate the importance of taking these into account when simulating ion-exchange resins operations. (author)

  19. Ion exchange of radionuclides on natural and modified micaceous minerals

    International Nuclear Information System (INIS)

    Kojvula, R.; Lekhto, Yu.

    1998-01-01

    Interaction of 134 Cs, 85 Sr and 60 Co with three micaceous minerals: muscovites, biotites and phlogopite is studied. Two types of micaceous minerals: natural ones, wherein potassium is an exchange cation, and samples, converted into sodium form, are studied/ It is found that biotite and phlogopite in the sodium form are specified by high selectivity to cobalt with distribution coefficient above 10 5 ml/g, whereas the muscovite potassium form is characterized by high selectivity to cesium. Neither of the micaceous minerals is characterized by selectivity to strontium. Distribution coefficients strongly depend on pH of the medium

  20. Copper Removal from A-01 Outfall by Ion Exchange

    International Nuclear Information System (INIS)

    Oji, L.N.

    1999-01-01

    Chelex100, a commercially available ion exchange resin, has been identified in this study as having a significant affinity for copper and zinc in the A-01 outfall water. Removal of copper and zinc from A-01 outfall water will ensure that the outfall meets the state of South Carolina's limit on these heavy metals

  1. Ion exchange technology in the nuclear fuel cycle

    International Nuclear Information System (INIS)

    1986-02-01

    The application of ion exchange has been expanded to various parts of the nuclear fuel cycle. Major applications are in uranium production facilities, nuclear power plants, spent fuel reprocessing and waste treatment. Furthermore, application to isotope separation has been under development. The appendix contains a compilation of resin data. A separate abstract was prepared for each of the 6 chapters in this technical document

  2. Thermal Analysis for Ion-Exchange Column System

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Si Y.; King, William D.

    2012-12-20

    Models have been developed to simulate the thermal characteristics of crystalline silicotitanate ion exchange media fully loaded with radioactive cesium either in a column configuration or distributed within a waste storage tank. This work was conducted to support the design and operation of a waste treatment process focused on treating dissolved, high-sodium salt waste solutions for the removal of specific radionuclides. The ion exchange column will be installed inside a high level waste storage tank at the Savannah River Site. After cesium loading, the ion exchange media may be transferred to the waste tank floor for interim storage. Models were used to predict temperature profiles in these areas of the system where the cesium-loaded media is expected to lead to localized regions of elevated temperature due to radiolytic decay. Normal operating conditions and accident scenarios (including loss of solution flow, inadvertent drainage, and loss of active cooling) were evaluated for the ion exchange column using bounding conditions to establish the design safety basis. The modeling results demonstrate that the baseline design using one central and four outer cooling tubes provides a highly efficient cooling mechanism for reducing the maximum column temperature. In-tank modeling results revealed that an idealized hemispherical mound shape leads to the highest tank floor temperatures. In contrast, even large volumes of CST distributed in a flat layer with a cylindrical shape do not result in significant floor heating.

  3. Increasing selectivity of a heterogeneous ion-exchange membrane

    Czech Academy of Sciences Publication Activity Database

    Křivčík, J.; Neděla, D.; Hadrava, J.; Brožová, Libuše

    2015-01-01

    Roč. 56, č. 12 (2015), s. 3160-3166 ISSN 1944-3994. [International Conference on Membrane and Electromembrane Processes - MELPRO 2014. Prague, 18.05.2014-21.05.2014] Institutional support: RVO:61389013 Keywords : ion-exchange membrane * selectivity * permselectivity Subject RIV: JP - Industrial Processing Impact factor: 1.272, year: 2015

  4. Loading ion exchange resins with uranium for HTGR fuel kernels

    International Nuclear Information System (INIS)

    Notz, K.J.; Greene, C.W.

    1976-12-01

    Uranium-loaded ion exchange beads provide an excellent starting material in the production of uranium carbide microspheres for nuclear fuel applications. Both strong-acid (sulfonate) and weak-acid (carboxylate) resins can be fully loaded with uranium from a uranyl nitrate solution utilizing either a batch method or a continuous column technique

  5. Field experiment on multicomponent ion exchange in a sandy aquifer

    International Nuclear Information System (INIS)

    Bjerg, P.L.; Christensen, T.H.

    1990-01-01

    A field experiment is performed in a sandy aquifer in order to study ion exchange processes and multicomponent solute transport modeling. An injection of groundwater spiked with sodium and potassium chloride was performed over a continuous period of 37 days. The plume is monitored by sampling 350 filters in a spatial grid. The sampling aims at establishing compound (calcium, magnesium, potassium, sodium, chloride) breakthrough curves at various filters 15 to 100 m from the point of injection and areal distribution maps at various cross sections from 0 to 200 m from the point of injection. A three-dimensional multicomponent solute transport model will be used to model the field experiments. The chemical model includes cation exchange, precipitation, dissolution, complexation, ionic strength and the carbonate system. Preliminary results from plume monitoring show that the plume migration is relatively well controlled considering the scale and conditions of the experiment. The transverse dispersion is small causing less dilution than expected. The ion exchange processes have an important influence on the plume composition. Retardation of the injected ions is substantial, especially for potassium. Calcium exhibits a substantial peak following chloride due to release from the ion exchange sites on the sediment. (Author) (8 refs., 5 figs., tab.)

  6. Sorption of Molecular Oxygen by Metal-Ion Exchanger Nanocomposites

    Science.gov (United States)

    Krysanov, V. A.; Plotnikova, N. V.; Kravchenko, T. A.

    2018-03-01

    Kinetic features are studied of the chemisorption and reduction of molecular oxygen from water by metal-ion exchanger nanocomposites that differ in the nature of the dispersed metal and state of oxidation. In the Pd equilibrium sorption coefficient for oxygen dissolved in water ranges from 20 to 50, depending on the nature and oxidation state of the metal component.

  7. Device for processing regenerative wastes of ion exchange resin

    International Nuclear Information System (INIS)

    Kuroda, Osamu; Ebara, Katsuya; Shindo, Toshikazu; Takahashi, Sankichi

    1986-01-01

    Purpose: To facilitate the operation and maintenance of a processing device by dividing radioactive wastes produced in the regenerative process of ion exchange resin into a regenerated usable recovery liquid and wastes. Constitution: Sulfuric acid is recovered by a diffusion dialysis method from wastes containing sulfuric acid that are generated in the regenerative process of cation-exchange resin and also caustic soda is recovered by the diffusion dialysis method from wastes containing caustic soda that are generated in the regenerative process of anion-exchange resin. The sulfuric acid and caustic soda thus recovered are used for the regeneration of ion-exchange resin. A concentrator is provided for concentrating the sulfuric acid and caustic soda water solution to concentration suitable for the regeneration of these ion-exchange resins. Also provided is a recovery device for recovering water generated from the concentrator. This device is of so simple a constitution that its operation and maintenance can be performed very easily, thereby greatly reducing the quantity of waste liquid required to be stored in drums. (Takahashi, M.)

  8. Isotope effects in ion-exchange equilibria in aqueous and mixed solvent systems

    International Nuclear Information System (INIS)

    Gupta, A.R.

    1979-01-01

    Isotope effects in ion-exchange equilibria in aqueous and mixed solvents are analyzed in terms of the general features of ion-exchange equilibria and of isotope effects in chemical equilibria. The special role of solvent fractionation effects in ion-exchange equilibria in mixed solvents is pointed out. The various situations arising in isotope fractionation in ion exchange in mixed solvents due to solvent fractionation effects are theoretically discussed. The experimental data on lithium isotope effects in ion-exchange equilibria in mixed solvents are shown to conform to the above situations. The limitations of ion-exchange equilibria in mixed solvents for isotope fractionation are pointed out. 3 tables

  9. Ion exchange characteristics of cerium (IV) and Tin(IV) antimonates and their use in rad waste treatment

    Energy Technology Data Exchange (ETDEWEB)

    Elnaggar, I M; Abdel Hamid, M M; Elabsy, M A; Aly, H F [Hot lab. centre, atomic energy authority, Cairo, (Egypt)

    1995-10-01

    Cerium (IV) and Tin(IV) antimonates cation exchangers have been synthesized. The products were characterized by powdered X-ray diffraction, thermal analysis and infrared spectrometry. The data of the distribution coefficients showed that the selectivity decreased in the order Eu{sup 3+}>Co{sup 2+}>Sr{sup 2+}>Cs{sup +} for both materials. Besides, the drying temperature of the matrices have a profound effect on their ion exchange capacities. Moreover, the obtained results of the effect of gamma radiation on the ion exchange behaviour of the samples showed that a slight decrease of the capacity and the distribution coefficient values with increasing the absorbed dose. 2 figs., 4 tabs.

  10. Co2+ ion exchange with NaY

    International Nuclear Information System (INIS)

    Garcia, I.; Solache-Rios, M.; Bulbulian, S.; Bosch, P.

    1993-01-01

    Co 2+ ion exchange from aqueous cobalt chloride-sodium chloride solutions with NaY zeolite has been investigated. The effect of contact time on the sorption of Co 2+ by dehydrated Y zeolite at 150 degrees C is unusual. A fast sorption uptake is observed in which 1.73 mequiv/g of zeolite of Na + ions is replaced by cobalt ions, followed by a desorption process where the uptake decreases to 1.56 mequiv/g of zeolite. This behavior is explained by the location and coordination of cobalt in Y zeolite sites. It is suggested that the maximum uptake corresponds to cobalt ions being simultaneously in two sites; tetrahedrally coordinated in the sodalite units and octahedrally coordinated in the large cavities. It is also suggested that the desorption process is a consequence of a reaction between Cl - ions and the tetrahedral species. 20 refs., 4 figs

  11. Comparative study on ion-isotopic exchange reaction kinetics by application of tracer technique

    International Nuclear Information System (INIS)

    Lokhande, R.S.; Singare, P.U.

    2007-01-01

    The radioactive isotopes 131 I and 82 Br were used to trace the ion-isotopic exchange reactions using industrial grade ion exchange resins Amberlite IRA-400. The experiments were performed to understand the effect of temperature and concentration of ionic solution on kinetics of exchange reactions. Both the exchange reactions were greatly influenced by rise in temperature, which result in higher percentage of ions exchanged. For bromide ion-isotopic exchange reactions, the calculated values of specific reaction rate/min -1 , and amount of ions exchanged/mmol were obtained higher than that for iodide ion-isotopic exchange reactions under identical experimental conditions. The observed variation in the results for two ion-isotopic exchange reactions was due to the difference in the ionic size of bromide and iodide ions. (orig.)

  12. Removal of Radioactive Nuclides by Multi-Functional Microcapsules Enclosing Inorganic Ion-Exchangers and Organic Extractants

    Energy Technology Data Exchange (ETDEWEB)

    Mimura, H.; Akiba, K.; Onodera, Y.

    2002-02-26

    The microcapsules enclosing two kinds of functional materials, inorganic ion-exchangers and organic extractants, were prepared by taking advantage of the high immobilization ability of alginate gel polymer. The fine powders of inorganic ion-exchanger and oil drops of extractant were kneaded with sodium alginate (NaALG) solution and the kneaded sol readily gelled in a salt solution of CaCl2, BaCl2 or HCl to form spherical gel particles. The uptake properties of various nuclides, 137Cs, 85Sr, 60Co, 88Y, 152Eu and 241Am, for thirty-four specimens of microcapsules in the presence of 10-1-10-4 M HNO3 were evaluated by the batch method. The distribution coefficient (Kd) of Cs+ above 103 cm3/g was obtained for the microcapsules enclosing CuFC or AMP. The Kd of Sr2+ around 102 cm3/g was obtained for the microcapsules containing clinoptilolite, antimonic acid, zeolite A, zeolite X or titanic acid. The microcapsules enclosing DEHPA exhibited relatively large Kd values of trivalent metal ions above 103 cm3/g; for example, the Kd values of Cs+, Sr2+, Co2+, Y3+, Eu3+ and Am3+ for a favorable microcapsule (CuFC/clinoptilolite/DEHPA/CaALG) were 1.1x104, 7.5x10, 1.1x10, 1.0x104, 1.4x104, 3.4x103 cm3/g, respectively. The uptake rates of Cs+, Y3+, Eu3+ and Am3+ for this microcapsule were rather fast; the uptake percentage above 90% was obtained after 19 h-shaking and the uptake equilibrium was attained within 1 d. The AMP/CaALG exhibited high uptake ability for Cs+ even after irradiation of 188 kGy, and DEHPA/CaALG microcapsule had similar Kd values of Cs+, Sr2+, Co2+, Y3+, Eu3+ and Am3+ ions before and after irradiation. The microcapsules with various shapes such as spherical, columnar, fibrous and filmy forms were easily prepared by changing the way of dipping kneaded sol into gelling salt solution. The microcapsules enclosing inorganic ion-exchangers and extractants have a potential possibility for the simultaneous removal of various radioactive nuclides from waste solutions.

  13. Study of the behaviour of inorganic ion exchangers in the treatment of medium active effluents. Part IV

    International Nuclear Information System (INIS)

    Beaven, G.W.; Cross, J.E.; Hooper, E.W.

    1988-01-01

    This report summarises some of the results from an ongoing experimental programme of work for the Department of the Environment on the potential use of inorganic ion exchangers for the treatment of medium active waste streams. Six different absorbers have been examined for their effectiveness in removing Am, Cs, Co, Sb, Ru, Eu, Ag, Zr, Nb, Zn and Mn ions from solutions varying from 4 M HNO 3 to 1 M NaNO 3 at pH 10. The ion exchangers tested were polyantimonic acid, hydrous titanium oxide, manganese dioxide, potassium copper hexacyanoferrate II, titanium phosphate and zirconium phosphate. The experimental results show that by suitable choice of absorber and operating conditions, good decontamination from all the radionuclides examined can be achieved. (author)

  14. Evaluation of selected ion exchangers for the removal of cesium from MVST W-25 supernate

    International Nuclear Information System (INIS)

    Collins, J.L.; Egan, B.Z.; Anderson, K.K.; Chase, C.W.; Mrochek, J.E.; Bell, J.T.; Jernigan, G.E.

    1995-04-01

    The goal of this batch-test equilibration study was to evaluate the effectiveness of certain ion exchangers for removing cesium from supernate taken from tank W-25 of the Melton Valley Storage Tank (MVST) Facility located at the Oak Ridge National Laboratory (ORNL). These exchangers were selective for removing cesium from alkaline supernatant solutions with high salt concentrations. Since the supernates of evaporator concentrates stored in tanks at the MVST facility have compositions similar to some of those stored in tanks at Hanford, the data generated in this study should prove useful in the overall evaluation of the ion exchangers for applications to Hanford and other US Department of Energy (USDOE) sites. A goal of the waste processing effort at Hanford is to remove enough cesium to ensure that the resulting LLW will meet the Nuclear Regulatory Commission (NRC) 10 CFR 61 class A limit for 137 Cs (1 Ci/m 3 or 1 μCi/mL). The separated cesium may be concentrated and vitrified for disposal in the high-level waste repository. The decontaminated effluent would be solidified for near-surface disposal

  15. Separation of seven arsenic species by ion-pair and ion-exchange high performance liquid chromatography

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Hansen, Sven Hedegaard

    1992-01-01

    Arsenite, arsenate, monomethylarsonate, dimethylarsinate, arsenobetaine, arsenocholine and the tetramethylarsonium ion were subjected to ion-exchange and ion-pair reversed phase HPLC. The ion exchange method was superior in selectivity and time of analysis for the arsenic anions. The ammonium ions...... used for the ion-pair method only resulted in separation of some of the anionic arsenic compounds. Flame atomic absorption spectrometry was used for on-line arsenic-specific detection....

  16. Chemical studies on the synthesis and characterization of some ion- exchange materials and its use in the treatment of hazardous wastes

    International Nuclear Information System (INIS)

    El-Deeb, A.B.I.

    2013-01-01

    Now inorganic ion exchange materials play an important role in analytical chemistry, based originally on their thermal and radiation resistance as well as their stability to chemical attack.Vanadate salts are one of the main categories of inorganic ion exchange materials widely used in separation and preconcentration of some toxic and hazardous elements from different waste media. Attempts in this study are focused on the preparation of two inorganic ion exchange materials ,Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) for treatment of hazardous waste.These material were characterized using X-ray spectra (XRD and XRF), IR, TGA-DTA and total elemental analysis studies. On the basis of distribution studies, the materials have been found that they are highly selective for Pb(II) and Cs(I)ions. Thermodynamic parameters (i.e. ΔG, ΔS and ΔH) have also been calculated for the adsorption of Pb 2+ , Cs + , Fe 3+ , Cd 2+ , Cu +2 , Zn 2+ and Co 2+ ions on Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) showing that the overall adsorption process is spontaneous and endothermic. The mechanism of diffusion of Fe 3+ , Co 2+ , Cu 2+ , Zn 2+ , Cd 2+ , Cs + and Pb 2+ ions for Tin Vanadate (SnV) and Titanium Potassium Vanadate(TiKV) as cation exchangers were studied as a function of particle size, concentration of the exchanging ions, reaction temperatures and drying temperatures. The exchange rate was controlled by a particle diffusion mechanism as a limited batch technique and is confirmed from straight lines of B versus 1/r 2 plots. The values of diffusion coefficients, activation energies and entropies of activation were calculated and their significance was discussed. The data obtained have been compared with that reported for other inorganic exchangers. Exchange isotherms for Cs + ,Co 2+ and Cd 2+ ions were determined at 25, 45 and 65±1 degree C. These isotherms showed that Cs + ,Co 2+ and Cd 2+ are physically adsorbed. Finally, separations of the above

  17. Biquadratic Exchange in CsMnxMg1-xBr3

    DEFF Research Database (Denmark)

    Falk, U.; Furrer, A.; Kjems, Jørgen

    1984-01-01

    The importance of higher-order exchange interaction in localized S-state systems is discussed. The equation of motion is solved for a one-dimensional antiferromagnet with bilinear and biquadratic exchange coupling. It is shown that the biquadratic exchange interaction usually cannot be derived from...

  18. Theoretical studies of the electronic structure of the ions KCs+ and RbCs+

    International Nuclear Information System (INIS)

    Abdul Al, Saleh Nabhan

    2000-01-01

    Author.the theoretical investigation of the electronic structure of the molecular ions KCs + and RbCs + , by using ab initio calculation, is being considered. Some of the approximation methods may form a theoretical model; with which many physical properties of molecular systems can be explored by once a mathematical procedure has been implanted through a computer program. This theoretical structure is referred to as ab initio electronic structure. The Hamiltonian for a multi-electron system cannot be separated into one-electron parts without making the independent electron approximation. The one-electron molecular wave function is referred to as molecular orbital (MO). The MOs may be expressed as linear combinations of atomic orbitals. Making the Born-Oppenheimer approximation, we seek to solve for the electronic eigenfunctions and eigenvalues with the nuclei fixed at various separation distances. A rigorous variational calculation on a system involves the following steps: write down the Hamiltonian operator for the system; Select some mathematical functional form ψ as the trial wave function. This form should have variable parameters (we take ψto be made up of Slater determinants containing molecular-spin orbitals); Minimize the average value of the energy (E) with respect to variations in the parameters. We describe an approach in the ab initio calculations, called the self-consistent field (SCF) method. The Hartree-Fock equation is obtained by requiring E to be stationary with respect to variations in ψ. The best MOs are eigenfunctions of the Fock operator. The instantaneous part of the interaction that SCF neglects is referred to as electron correlation. One general technique, for including the effects of correlation, is called configuration interaction (CI). Moeller-Plesset perturbation theory is an alternative approach to the correlation problem. The calculation has been performed for the two molecular ions, through the CI PSI (Configuration Interaction

  19. Ion-Exchange Processes and Mechanisms in Glasses

    International Nuclear Information System (INIS)

    McGrail, B.P.; Icenhower, J.P.; Darab, J.G.; Shuh, D.K.; Baer, D.R.; Shutthanandan, V.; Thevuthasan, S.; Engelhard, M.H.; Steele, J.L.; Rodriguez, E.A.; Liu, P.; Ivanov, K.E.; Booth, C.H.; Nachimuthu, P.

    2001-01-01

    Leaching of alkalis from glass is widely recognized as an important mechanism in the initial stages of glass-water interactions. Pioneering experimental studies [1-3] nearly thirty-five years ago established that alkali (designated as M + ) are lost to solution more rapidly than network-forming cations. The overall chemical reaction describing the process can be written as: (triple b ond)Si-O-M + H + → (triple b ond)Si-OH + M + (1) or (triple b ond)Si-O-M + H 3 O + → (triple b ond)Si-OH + M + + H 2 O. (2) Doremus and coworkers [4-7] fashioned a quantitative model where M + ions in the glass are exchanged for counter-diffusing H 3 O + or H + . Subsequent investigations [8], which have relied heavily on reaction layer analysis, recognized the role of H 2 O molecules in the alkali-exchange process, without minimizing the importance of charged hydrogen species. Beginning in the 1980s, however, interest in M + -H + exchange reactions in silicate glasses diminished considerably because important experimental observations showed that network hydrolysis and dissolution rates were principally controlled by the chemical potential difference between the glass and solution (chemical affinity) [9]. For nuclear waste glasses, formation of alteration products or secondary phases that remove important elements from solution, particularly Si, was found to have very large impacts on glass dissolution rates [10,11]. Consequently, recent work on glass/water interactions has focused on understanding this process and incorporating it into models [12]. The ion-exchange process has been largely ignored because it has been thought to be a short duration, secondary or tertiary process that had little or no bearing on long-term corrosion or radionuclide release rates from glasses [13]. The only significant effect identified in the literature that is attributed to alkali ion exchange is an increase in solution pH in static laboratory tests conducted at high surface area-to-volume ratios

  20. Mobility of Rb{sup +} and Cs{sup +} ions in gases at high pressures; Mobilite des ions Rb{sup +} et Cs{sup +} dans les gaz a haute pression

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    A theoretical study and mobility measurements have been made of Rb{sup +} and Cs{sup +} ions moving in gases at high pressures (10{sup -2} to 25 kg/cm{sup 2}). The theoretical study has been effected using the results of P. Langevin who considers the ions and molecules as elastic spheres and takes into account the electrical polarization forces. The practical work has been carried out using the Rb{sup +} and Cs{sup +} ions emitted by a thermal source; for the measurement of their velocity the method using an ionic beam cut by four grids was employed. Since the source does not work in atmospheres containing oxygen (even in the combined state) the tests only involved pure gases: nitrogen, argon, helium at pressures of from 10{sup -2} to 12 kg/cm{sup 2}. The overall results show that the Rb{sup +} and Cs{sup +} ionic mobilities are very similar and that for fairly-short times spent by the ions in the gas, the measurement results are in agreement with theory. An increase in these times favours a degradation of the ions, which always leads to a decrease in the mobility. This effect is most marked in helium. The gases argon and nitrogen behave identically towards Rb{sup +} and Cs{sup +} ions. (author) [French] Une etude theorique et des mesures de mobilite ont ete effectuees pour des ions Rb{sup +} et Cs{sup +} se deplacant dans des gaz a haute pression (10{sup -2} a 25 kg/cm{sup 2}). L'etude theorique a ete effectuee en utilisant les resultats de P. Langevin qui assimile les ions et les molecules a des spheres elastiques et tient compte des forces de polarisation electrique. L'etude pratique a ete realisee en utilisant des ions Rb{sup +} et Cs{sup +} emis par une source thermique et pour la mesure de leur vitesse, la methode de coupure du faisceau ionique au moyen de quatre grilles a ete adoptee. La source ne fonctionnant pas dans des atmospheres contenant de l'oxygene (meme a l'etat combine) les essais ont seulement porte sur des gaz purs: azote

  1. Mobility of Rb{sup +} and Cs{sup +} ions in gases at high pressures; Mobilite des ions Rb{sup +} et Cs{sup +} dans les gaz a haute pression

    Energy Technology Data Exchange (ETDEWEB)

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

    1965-07-01

    A theoretical study and mobility measurements have been made of Rb{sup +} and Cs{sup +} ions moving in gases at high pressures (10{sup -2} to 25 kg/cm{sup 2}). The theoretical study has been effected using the results of P. Langevin who considers the ions and molecules as elastic spheres and takes into account the electrical polarization forces. The practical work has been carried out using the Rb{sup +} and Cs{sup +} ions emitted by a thermal source; for the measurement of their velocity the method using an ionic beam cut by four grids was employed. Since the source does not work in atmospheres containing oxygen (even in the combined state) the tests only involved pure gases: nitrogen, argon, helium at pressures of from 10{sup -2} to 12 kg/cm{sup 2}. The overall results show that the Rb{sup +} and Cs{sup +} ionic mobilities are very similar and that for fairly-short times spent by the ions in the gas, the measurement results are in agreement with theory. An increase in these times favours a degradation of the ions, which always leads to a decrease in the mobility. This effect is most marked in helium. The gases argon and nitrogen behave identically towards Rb{sup +} and Cs{sup +} ions. (author) [French] Une etude theorique et des mesures de mobilite ont ete effectuees pour des ions Rb{sup +} et Cs{sup +} se deplacant dans des gaz a haute pression (10{sup -2} a 25 kg/cm{sup 2}). L'etude theorique a ete effectuee en utilisant les resultats de P. Langevin qui assimile les ions et les molecules a des spheres elastiques et tient compte des forces de polarisation electrique. L'etude pratique a ete realisee en utilisant des ions Rb{sup +} et Cs{sup +} emis par une source thermique et pour la mesure de leur vitesse, la methode de coupure du faisceau ionique au moyen de quatre grilles a ete adoptee. La source ne fonctionnant pas dans des atmospheres contenant de l'oxygene (meme a l'etat combine) les essais ont seulement porte sur des gaz purs: azote, argon, helium et pour

  2. Application of radioactive tracers in upgradation of industrial grade ion exchange resin (Amberlite IRA-400)

    International Nuclear Information System (INIS)

    Lokhande, R.S.; Singare, P.U.

    1998-01-01

    The exchange rates of ion exchange are determined by application of 131 I as a tracer isotope. The exchange study carried out in this investigation deals with understanding the effectiveness of ion exchange resin (in iodide form) Amberlite IRA-400 at different concentrations of potassium iodide solution (electrolyte) with temperature of solution varying from 27-48 degC by keeping amount of ion exchange resin constant (1.0 g). The exchange study is also carried out by varying amount of ion exchange resins, for fixed temperature (27.0 degC) and for fixed concentration of potassium iodide solution (0.005 M). (author)

  3. Regenerating ion-exchangers used in uranium recovery

    International Nuclear Information System (INIS)

    Yan, T.; Espenscheid, W.F.

    1984-01-01

    The process claimed restores the ion exchange capacity of a strong base anion exchange resin used for recovering uranium from solutions used to leach uranium from subterranean formations. The resin is eluted with hydrochloric acid to remove uranium in the form of uranyl carbonate anions. It is then washed with a solution containing 0.5 to 100 g/l of sodium carbonate, sodium bicarbonate, or mixtures of both carbonate and bicarbonate until it is free of materials which are either soluble in the solution or react with the solution

  4. Study on rare earths complexes separation by means of different type of ion exchangers

    International Nuclear Information System (INIS)

    Hubicka, H.

    1990-01-01

    The applicability of different types of ion exchangers for purification and separation of rare earths complexes has been examined. The experimental work has been carried out on 14 chelating ion exchangers. The investigation results proved the great usefulness chelating ion exchangers especially of amino acid and phosphorus-type. Application of that type ion exchangers in column chromatographic process gave the excellent rare earths separation as well as enabled to obtain their preparates of high purity. 218 refs, 21 figs, 27 tabs

  5. Ion exchange and electrochemical evaluation of the microporous phosphate Li9Fe7(PO4)10

    International Nuclear Information System (INIS)

    Becht, Gregory A.; Vaughey, John T.; Britt, Robin L.; Eagle, Cassandra T.; Hwu, Shiou-Jyh

    2008-01-01

    A new lithium iron(III) phosphate, Li 9 Fe 7 (PO 4 ) 10 , has been synthesized and is currently under electrochemical evaluation as an anode material for rechargeable lithium-ion battery applications. The sample was prepared via the ion exchange reaction of Cs 5 K 4 Fe 7 (PO 4 ) 10 1 in the 1 M LiNO 3 solution under hydrothermal conditions at 200 deg. C. The fully Li + -exchanged sample Li 9 Fe 7 (PO 4 ) 10 2 cannot yet be synthesized by conventional high-temperature, solid-state methods. The parent compound 1 is a member of the Cs 9-x K x Fe 7 (PO 4 ) 10 series that was previously isolated from a high-temperature (750 deg. C) reaction employing the eutectic CsCl/KCl molten salt. The polycrystalline solid 1 was first prepared in a stoichiometric reaction via conventional solid-state method then followed by ion exchange giving rise to 2. Both compounds adopt three-dimensional structures that consist of orthogonally interconnected channels where electropositive ions reside. It has been demonstrated that the Cs 9-x K x Fe 7 (PO 4 ) 10 series possesses versatile ion exchange capabilities with all the monovalent alkali metal and silver cations due to its facile pathways for ion transport. 1 and 2 were subject to electrochemical analysis and preliminary results suggest that the latter can be considered as an anode material. Electrochemical results indicate that Li 9 Fe 7 (PO 4 ) 10 is reduced below 1 V (vs. Li) to most likely form a Fe(0)/Li 3 PO 4 composite material, which can subsequently be cycled reversibly at relatively low potential. An initial capacity of 250 mAh/g was measured, which is equivalent to the insertion of thirteen Li atoms per Li 9+x Fe 7 (PO 4 ) 10 (x = 13) during the charge/discharge process (Fe 2+ + 2e → Fe 0 ). Furthermore, 2 shows a lower reduction potential (0.9 V), by approximately 200 mV, and much better electrochemical reversibility than iron(III) phosphate, FePO 4 , highlighting the value of improving the ionic conductivity of the sample

  6. Treatment of low-activity-level process wastewaters by Continuous Countercurrent Ion Exchange

    International Nuclear Information System (INIS)

    Hall, R.; Watson, J.S.; Robinson, S.M.

    1990-01-01

    This paper discusses application of the Thomas model for predicting breakthrough curves from ion exchange column tests, methods for scale-up of experimental small-scaled ion exchange columns to industrial scale columns, and methods for predicting effluent compositions in a continuous countercurrent ion exchange system. 20 refs., 6 figs., 2 tabs

  7. Organic and inorganic ion exchangers as catalysts for the heterogeneous alkylation of aromatics

    Energy Technology Data Exchange (ETDEWEB)

    Klein, J; Widdecke, H [Technische Univ. Braunschweig (Germany, F.R.). Inst. fuer Chemische Technologie

    1979-06-01

    Ion exchangers have advantages over low molecular for use in industrial alkylation reactions. The reactivity and selectivity behaviour of the polymeric catalysts was found to be markedly influenced by the structure of the polymeric matrix as well as the type and number of the functional groups. In this connection many similarities between inorganic ion exchangers (zeolites) and organic ion exchange resins were detected.

  8. Ion exchange equilibrium for some uni-univalent and uni-divalent

    African Journals Online (AJOL)

    a

    KEY WORDS: Duolite A-102 D ion exchange resin, Equilibrium constant, Endothermic ion exchange reaction,. Enthalpy, Thermodynamic study. INTRODUCTION. For proper selection of ion exchange resin in a particular technical application, it is essential to have adequate knowledge regarding their physical and chemical ...

  9. Method of separating radioactive nuclides from ion exchange resins

    International Nuclear Information System (INIS)

    Suzuki, Kazunori; Saikoku, Masami; Taneta, Daisuke; Yagi, Takuro.

    1987-01-01

    Purpose: To enable to safely process radioactive nuclides from spent ion exchange resins by using existent processing facilities. Method: Ion exchange resins in aqueous medium are at first placed to the ultrasonic wave irradiation site and put into such a state where clads and resins are easily separatable from each other by weakening the bonding force between them. Since the clads are magnetic material such as Fe 3 O 4 or NiFe 2 O 4 , the clads can be collected in the direction of the magnetic force by exerting the magnetic field simultaneously. The collected clads are transported by means of the aqueous medium to a collecting tank by removing the effect of magnetic field, for example, by interrupting the current supply to the electromagnet. Finally, they were subjected to stabilization and fixation into inorganic hardening agent such as cement hardener. Thus, processions can be made safely by using existent facilities. (Takahashi, M.)

  10. Calcium isotope fractionation in ion-exchange chromatography

    International Nuclear Information System (INIS)

    Russell, W.A.; Papanastassiou, D.A.

    1978-01-01

    Significant fractionation of the isotopes of calcium has been observed during elution through short ion-exchange columns packed with Dowex 50W-X8 resin. A double isotopic tracer was used to provide correction for instrumental fractionation effects. The absolute 40 Ca/ 44 Ca ratio is determined by this method to 0.05% and provides a measure of the fractionation of all Ca isotopes. It is found that the lighter isotopes are preferentially retained by the resin, with variations in 40 Ca/ 44 Ca between the first and last fractions of up to 1.1%. An estimate of the separation factor between batch solute and resin gives epsilon = 2.1 x 10 -4 . Details of the chemical or physical mechanisms causing isotope fractionation of Li, Na, Ca, and other elements during ion-exchange chromatography are not yet clear

  11. Solidification of ion exchange resin wastes in hydraulic cement

    International Nuclear Information System (INIS)

    Neilson, R.M. Jr.; Kalb, P.; Fuhrmann, M.; Colombo, P.

    1982-01-01

    Work has been conducted to investigate the solidification of ion exchange resin wastes with portland cements. These efforts have been directed toward the development of acceptable formulations for the solidification of ion exchange resin wastes and the characterization of the resultant waste forms. This paper describes formulation development work and defines acceptable formulations in terms of ternary phase compositional diagrams. The effects of cement type, resin type, resin loading, waste/cement ratio and water/cement ratio are described. The leachability of unsolidified and solidified resin waste forms and its relationship to full-scale waste form behavior is discussed. Gamma irradiation was found to improve waste form integrity, apparently as a result of increased resin crosslinking. Modifications to improve waste form integrity are described. 3 tables

  12. Operating experience with ion exchanger beds in CIRUS

    International Nuclear Information System (INIS)

    Acharya, V.N.; Hajra, P.

    1977-01-01

    Operating experience with the ion exchanger beds in CIRUS reactor is narrated. Ion exchangers are provided for demineralisation of make up water and purification of closed loop water circuits. Exhaustion of resin is assessed on the basis of CO 2 concentration in the helium vent gas of the heavy water system. It is recommended that valves in the resin columns for rod handling bays be located outside the enclosure and each bed to reduce man-rem consumption during maintenance. Repeated backwash of the bed reduces chocking of water space with resin fines. Preventive maintenance avoids leakage past valves. Active resin from the resin beds is removed by hydraulic transfer method. (M.G.B.)

  13. Ion exchange and luminescence of Eu3+ in Nafion membranes

    International Nuclear Information System (INIS)

    Petushkov, A.A.; Shilov, S.M.; Pak, V.N.

    2006-01-01

    Dehydration of Nafion perfluorosulphonic membranes at 110 deg C results in a significant reduction of their void space volume, the accessibility of sulphonic groups and the total exchange capacity towards Eu 3+ cations. Nevertheless, the ion exchange sorption of Eu 3+ takes place in accordance with stoichiometric ratio [-SO 3 H]/[Eu 3+ ]=3. The membranes thermal pretreatment also affects noticeably the spectroscopic features of the fastened Eu 3+ ions, such as the relationship between the intensities of the hypersensitive 5 D 0 → 7 F 2 and magnetic dipolar 5 D 0 → 7 F 1 transitions, the excited state life time, as well as the luminescence quenching in the course of water adsorption

  14. Charge exchange in collisions of beryllium with its ion.

    Science.gov (United States)

    Zhang, Peng; Dalgarno, Alexander; Côté, Robin; Bodo, Enrico

    2011-11-14

    Close-coupling calculations of the resonance and near resonance charge exchange in ion-atom collisions of Be at low and intermediate energies are presented. Accurate ab initio calculations are carried out of the Born-Oppenheimer potentials and the non-adiabatic couplings that are due to the finite nuclear masses and drive the near resonance charge exchange. We show that the near resonance charge exchange cross section follows Wigner's threshold law of inelastic processes for energies below 10(-8) eV and that the zero temperature rate constant for it is 4.5 × 10(-10) cm(3) s(-1). At collision energies much larger than the isotope shift of the ionization potentials of the atoms, we show that the near resonance charge exchange process is equivalent to the resonance charge exchange with cross sections having a logarithmic dependence. We also investigate the perturbation to the charge exchange process due to the non-adiabatic interaction to an electronic excited state. We show that the influence is negligible at low temperatures and still small at intermediate energies despite the presence of resonances.

  15. Thermodynamics of ion-exchange on ferric antimonate

    International Nuclear Information System (INIS)

    Rawat, J.P.; Muktawat, K.P.S.

    1981-01-01

    A simple approach to ion-exchange equilibria on ferric antimonate has been applied. The values of selectivity coefficients for Ba 2+ , Mg 2+ , Ca 2+ and Sr 2+ have been measured using equilibrium experiments at constant ionic strength and at different temperatures from 20 to 60 0 C. The thermodynamic equilibrium constant and values of ΔG 0 , ΔH 0 and ΔS 0 are reported. (author)

  16. Inclusion of radioactive ion-exchange resins into inorganic binders

    International Nuclear Information System (INIS)

    Epimakhov, V.N.; Olejnik, M.S.

    2005-01-01

    The paper is devoted to inclusion of the radioactive ion-exchange resins into the portland, slag-portland and alumina cements. The degree of filling the solidified products achieves 7-10, 12 and 18.9-19.7% correspondingly under conservation of sufficient strength (not less 5 MPa). The coefficient of waste volume increasing during solidification does not exceed 1.5 under consideration of addition of 10 mass % of clay into aluminia cement [ru

  17. Exchange interpretation of anomalous back angle heavy ion elastic scattering

    International Nuclear Information System (INIS)

    Zisman, M.S.

    1977-10-01

    Anomalous back angle oscillations in the angular distributions obtained in the elastic scattering of 16 O + 28 Si and 12 C + 28 Si have been interpreted in terms of an elastic cluster transfer comparable to that observed in other heavy ion reactions. The calculations appear to at least qualitatively explain the data with respect to the existence and phase of the back angle oscillations. The results indicate that an exchange mechanism may play an important role in the oscillations

  18. Momentum transfer in relativistic heavy ion charge-exchange reactions

    Science.gov (United States)

    Townsend, L. W.; Wilson, J. W.; Khan, F.; Khandelwal, G. S.

    1991-01-01

    Relativistic heavy ion charge-exchange reactions yield fragments (Delta-Z = + 1) whose longitudinal momentum distributions are downshifted by larger values than those associated with the remaining fragments (Delta-Z = 1, -2,...). Kinematics alone cannot account for the observed downshifts; therefore, an additional contribution from collision dynamics must be included. In this work, an optical model description of collision momentum transfer is used to estimate the additional dynamical momentum downshift. Good agreement between theoretical estimates and experimental data is obtained.

  19. Separation of organic ion exchange resins from sludge - engineering study

    International Nuclear Information System (INIS)

    Duncan, J.B.

    1998-01-01

    This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation

  20. Separation of organic ion exchange resins from sludge -- engineering study

    Energy Technology Data Exchange (ETDEWEB)

    Duncan, J.B.

    1998-08-25

    This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation.

  1. Recovery of tretrachloroaurate through ion exchange with Dowex 11 resin

    International Nuclear Information System (INIS)

    Alguacil, F.J.

    1998-01-01

    The recovery of the tretrachloroaurate complex by the anionic ion exchange resin Dowex 11 has been studied. The kinetics of gold adsorption were dependent of both gold and resin concentrations and temperature. The adsorption isotherm can be described by the expression Q=kC''n. The loaded resin could be eluted by an acidic thiourea solution at 20 degree centigree. After several adsorption-elution cycles there is not any apparent loss in the adsorption properties of the resin. (Author) 6 refs

  2. Yttrium and rare earths separation by ion exchange resin

    International Nuclear Information System (INIS)

    Pinatti, D.G.; Ayres, M.J.G.; Ribeiro, S.; Silva, G.L.J.P.; Silva, M.L.C.P.; Martins, A.H.

    1988-01-01

    The experimental results of yttrium and rare earths separation from Brazilian xenotime are presented. The research consist in five stage: 1) Preparation of yttrium, erbium and lutetium standard solutions, from solubilization of pure oxides 2) yttrium and rare earths separation by ion exchange chromatrography 3) Separation and recovery of EDTA 4) Precipitation and calcination and 4) Analytical control of process. (C.G.C.) [pt

  3. Synthesis of ion-exchange resin for selective thorium and uranyl ions sorption

    Science.gov (United States)

    Konovalov, Konstantin; Sachkov, Victor

    2017-11-01

    In this work, the method of ion-exchange resin synthesis selective to radionuclides (uranium and thorium) is presented. The method includes synthesis of polymeric styrene-divinylbenzene macroporous matrix with size of 0.1-0.2 mm, and its subsequent transformation by nitration and then reduction by tin (II) chloride. For passivation of active primary amines partially oxidation by oxygen from air is used. Obtained ion-exchange resin has ratio of sorption sum U+Th to sorption sum of other total rare-earth elements as 1:1.88 at ratio of solid to liquid phase 1:200. The proposed method of ion-exchange resin synthesis is scaled-up for laboratory reactors with volume of 5 and 50 liters.

  4. Environmental applications of natural zeolitic materials based on their ion-exchange properties

    International Nuclear Information System (INIS)

    Colella, C.

    1998-01-01

    Natural zeolites, such as clinoptilolite, chabazite, phillipsite and mordenite, exhibit good selectivities for some water pollutants, e.g., Cs + , NH 4 + and Pb 2+ . Zeolite-rich tuffs may be therefore utilized for removing the above and other cations from wastewaters before discharge. Continuous processes with fixed beds are usually employed for water purification, such as those in service in the U.S.A for ammonium removal from municipal sewage. Direct action of the ion exchanger is needed when the pollutant must be removed from soil and trapped in the zeolite framework. Discontinuous processes (addition of zeolite to the waste solution) are also possible, provided the polluted zeolitic sludge is stabilized-solidified in a cement matrix matrix before disposal. Removal of radionuclides from nuclear power plant waters with natural zeolites is discussed

  5. Modeling strontium-cesium-calcium-magnesium-sodium ion exchange equilibria on chabazite with the Wilson equation

    International Nuclear Information System (INIS)

    Perona, J.J.

    1992-01-01

    Chabazite zeolites are used at ORNL for decontamination of wastewaters containing 90 Sr and 137 Cs. Treatability studies have shown that chabazite can remove trace amounts of these nuclides from wastewaters containing much higher concentrations of calcium and magnesium. The design of ion exchange columns for multicomponent systems requires a method for predicting multicomponent equilibria from binary or ternary experiments, since the number of experiments required for an empirical equilibrium model is generally not feasible. Binary interaction parameters for the Wilson equation were used to predict solid-phase activity coefficients for the five-component system, and the sum of squares of deviations between experimental and predicted solution concentrations for the data points available was calculated. The average deviation per data point for the five-component system was about the same as for the calcium-magnesium-sodium ternary system

  6. 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)

    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 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 60 Cs gamma irradiation in water or 0.5M HNO 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).)

  7. Ion exchange properties of zeolite-containing catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Koval' chuk, L V; Takhtarova, G N; Topchieva, K V [Moskovskii Gosudarstvennyi Univ. (USSR). Kafedra Fizicheskoi Khimii

    1975-03-01

    In the paper the reaction of sodium ion exchange for ammonium cations, cations of calcium and lanthanum in the amorphous aluminium silicate Na/sub 0,856/(AlO/sub 2/)(SiO/sub 2/)/sub 9,831/, zeolite Na/sub 1/(AlO/sub 2/)(SiO/sub 2/)/sub 2,33/ and zeolite containing catalyst Na/sub 1,09/(AlO/sub 2/)(SiOsub(2))/sub 7,93/ were studied; exchange isotherms of sodium for ammonium, calcium and lanthanium are presented. Results received in the study indicate high selectivity of zeolite for calcium and lanthanum cations in comparison with amorphous aluminium silicate and also display electroselectivity effect. The highest separation coefficient takes place for lanthanum in the sodium exchange in zeolite.

  8. Ion exchange resin fouling of molybdenum in recovery uranium processess

    International Nuclear Information System (INIS)

    Zhang Guowei; Zhao Guirong

    1990-09-01

    The relationship between anion exchange resin fouling and molybdic acid polymerization was studied. By using potentiometer titration and laser-Raman spectroscopy the relationship of molybdic acid polymerization and the pH value of solution or the molybdenum concentration was determined. It was shown that as the concentration of initial molybdenum in solution decreases from 0.2 mol/L to 0.5 mmol/L, the pH value of starting polymerization decreased from 6.5 to 4.5. The experimental results show that the fouling of 201 x 7 resin in the acidic solution is mainly caused by the adsorbing of Mo 3 O 26 4- ion and occupying the exchange radical site of the resin. Under the leaching conditions the molybdenum and phosphate existing in the leaching liquor can form 12-molybdo-phosphate ion. It also leads to resin fouling. The molybdenum on the fouled resin can synergically be desorbed by mixed desorbents containing ammonium hydroxide and ammonium sulfate. The desorbed resin can be used for uranium adsorption and the desorbed molybdenum can be recovered by ion exchange method

  9. Radiation effects on ion exchange materials used in waste management

    International Nuclear Information System (INIS)

    Pillay, K.K.S.

    1982-01-01

    Radiation damage to process materials used in radioactive waste management has been a topic of little interest in the past. In recent years, as a result of the increasing number of accidents reported in the open literature, there has been some desire to examine the radiation decomposition of ion exchange materials and its consequences to the interim and long-term management of radioactive wastes. Extensive literature surveys and some confirmatory laboratory investigations conducted conclusively demonstrate that radiation damage to ion exchangers has the potential to cause problems of corrosion, elution of adsorbed ionic species, generation of flammable and explosive gaseous products and agglomeration of particulates to form rigid monoliths. This paper is an overview of present knowledge and a presentation of the results of our investigations of this phenomenon. The distinct lack of systematic studies to evaluate the problems of radiation damage to process materials used in the consolidation and isolation of high specific activity radionuclides still leaves considerable gaps in our knowledge of the processes and consequences of radiation effects on ion exchangers used in radioactive waste management

  10. Increase of ionic conductivity in the microporous lithosilicate RUB-29 by Na-ion exchange processes

    International Nuclear Information System (INIS)

    Park, S.-H.; Senyshyn, A.; Paulmann, C.

    2007-01-01

    The ionic conductivity in the zeolite-like lithosilicate RUB-29 (Cs 14 Li 24 [Li 18 Si 72 O 172 ].14H 2 O [S.-H. Park, J.B. Parise, H. Gies, H. Liu, C.P. Grey, B.H. Toby, J. Am. Chem. Soc. 122 (2000) 11023-11024]) increases via simple ion-exchange processes, in particular when Na cations replace a part of Cs + and Li + of the material. The resulting ionic conductivity value of 3.2x10 -3 S cm -1 at 885 K is about two orders higher than that for the original material [S.-H. Park, J.B. Parise, M.E. Franke, T. Seydel, C. Paulmann, Micropor. Mesopor. Mater., in print ( (doi:10.1016/j.micromeso.2007.03.040) available online since April 19, 2007)]. The structural basis of a Na + -exchanged RUB-29 sample (Na-RUB-29) at 673 K could be elucidated by means of neutron powder diffraction. Rietveld refinements confirmed the replacement of Na + for both parts of Cs and Li cations, agreeing with idealized cell content, Na 8 Cs 8 Li 40 Si 72 O 172 . As a result of the incorporation of Na + in large pores, the number of Li + vacancies in dense Li 2 O-layers of the structure could increase. This can be one of the main reasons for the improved conductivity in Na-RUB-29. In addition, mobile Na cations may also contribute to the conductivity in Na-RUB-29 as continuous scattering length densities were found around the sites for Na in difference Fourier map. - Graphical abstract: Li 2 O-layers formed by edge- and corner-sharing LiO 4 - and LiO 3 -moieties in the zeolite-like lithosilicate RUB-29 provide optimal pathways for conducting Li + . The number of empty Li sites in this layer-like configuration could increase via 'simple' Na + -exchange processes, promoting fast Li motions

  11. Composite sorbents of inorganic ion-exchangers and polyacrylonitrile binding matrix. Methods of modification of properties of inorganic ion-exchangers for application in column packed beds

    International Nuclear Information System (INIS)

    Sebesta, F.

    1997-01-01

    Methods of preparation of granules of inorganic ion exchangers as well as methods for improvement of granular strength of these materials are reviewed. The resulting ion exchangers are classified in three groups - 'intrinsic', supported and composite ion exchangers. Their properties are compared and possibilities of their technological application are evaluated. A new method of preparation of inorganic-organic composite sorbents of inorganic ion-exchangers and polyacrylonitrile binding matrix is described, advantages and disadvantages of such sorbents are discussed. Proposed fields of application include tratment of liquid radioactive and/or hazardous wastes, decontamination of natural water as well as analytical applications. (author)

  12. On-line ion chemistry for the AMS analysis of {sup 90}Sr and {sup 135,137}Cs

    Energy Technology Data Exchange (ETDEWEB)

    Eliades, J. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON, M5S 1A7 (Canada); Zhao, X.-L. [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, K1N 6N5 (Canada); Litherland, A.E. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON, M5S 1A7 (Canada); Kieser, W.E., E-mail: liam.kieser@utoronto.ca [Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON, K1N 6N5 (Canada)

    2013-01-15

    The analysis of {sup 90}Sr by AMS has so far required the use of very large tandem accelerators in order to separate the isobar {sup 90}Zr by the rate-of-energy-loss method. The analysis of {sup 135,137}Cs by AMS has never been attempted as the separation of the isobars {sup 135,137}Ba by the traditional method requires even higher energies, so that this approach would become prohibitively expensive for routine analysis. Following the successful demonstration of Cl{sup -}-S{sup -} separation by the Isobar Separator, the same apparatus was used to test the separation of other pairs of isobars. Surprisingly effective results were obtained with NO{sub 2} gas in the cases of SrF{sub 3}{sup -}-ZrF{sub 3}{sup -} and CsF{sub 2}{sup -}-BaF{sub 2}{sup -} separations. Reduction factors of {approx}4 Multiplication-Sign 10{sup -6} for ZrF{sub 3}{sup -}/SrF{sub 3}{sup -} and {approx}2 Multiplication-Sign 10{sup -5} for BaF{sub 2}{sup -}/CsF{sub 2}{sup -} were measured. SrF{sub 3}{sup -} and CsF{sub 2}{sup -} are both super-halogen anions and are preferentially produced in the ion source rather than ZrF{sub 3}{sup -} and BaF{sub 2}{sup -} when using the PbF{sub 2} matrix-assisted method. Reduction factors for ion source production with such targets of {approx}3 Multiplication-Sign 10{sup -5} for ZrF{sub 3}{sup -}-SrF{sub 3}{sup -} and {approx}5 Multiplication-Sign 10{sup -4} for BaF{sub 2}{sup -}-CsF{sub 2}{sup -} were found. The combined methods would suggest a theoretical detection sensitivity for {sup 90}Sr/Sr {approx}6 Multiplication-Sign 10{sup -16}, {sup 135}Cs/Cs {approx}7 Multiplication-Sign 10{sup -15} and {sup 137}Cs/Cs {approx}1 Multiplication-Sign 10{sup -14}, assuming 10 ppm Zr and Ba contamination in the AMS targets. In addition to the earlier Cl{sup -}-S{sup -} separation work, these measurements further illustrate the potential of on-line ion chemical methods for broadening the analytical scope of small AMS systems.

  13. Modeling the ion transfer and polarization of ion exchange membranes in bioelectrochemical systems.

    Science.gov (United States)

    Harnisch, Falk; Warmbier, Robert; Schneider, Ralf; Schröder, Uwe

    2009-06-01

    An explicit numerical model for the charge balancing ion transfer across monopolar ion exchange membranes under conditions of bioelectrochemical systems is presented. Diffusion and migration equations have been solved according to the Nernst-Planck Equation and the resulting ion concentrations, pH values and the resistance values of the membrane for different conditions were computed. The modeling results underline the principle limitations of the application of ion exchange membranes in biological fuel cells and electrolyzers, caused by the inherent occurrence of a pH-gradient between anode and cathode compartment, and an increased ohmic membrane resistance at decreasing electrolyte concentrations. Finally, the physical and numerical limitations of the model are discussed.

  14. Charge-exchange collisions of multiply charged ions with atoms

    International Nuclear Information System (INIS)

    Grozdanov, T.P.; Janev, R.K.

    1978-01-01

    The problem of electron transfer between neutral atoms and multiply charged ions is considered at low and medium energies. It is assumed that a large number of final states are available for the electron transition so that the electron-capture process is treated as a tunnel effect caused by the strong attractive Coulomb field of the multicharged ions. The electron transition probability is obtained in a closed form using the modified-comparison-equation method to solve the Schroedinger equation. An approximately linear dependence of the one-electron transfer cross section on the charge of multicharged ion is found. Cross-section calculations of a number of charge-exchange reactions are performed

  15. Possibility of sorption purification of chromium comprising waste waters of galvanic production by inorganic ion exchangers

    International Nuclear Information System (INIS)

    Khaynakov, S.A.; Likov, E.P.; Bortun, A.I.; Belyukov, V.N.

    1986-01-01

    Present work is devoted to possibilities of sorption purification of chromium comprising waste waters of galvanic production by inorganic ion exchangers. Thus, the comparative study of sorption of chromium ions on anion exchanger A B-17 and on inorganic ion exchangers on the basis of hydrated titanium and zirconium dioxides in static and dynamic conditions is conducted. The influence of chromium ions concentration, solutions acidity (ph=1÷12) and presence of base electrolyte on sorption is studied. The state of chromium ions sorbed by inorganic ion exchangers is studied by means of infrared spectroscopy and spectroscopy. It is defined that inorganic sorbents could be used for chromium extraction from different solutions.

  16. Low-emittance uniform density Cs+ sources for heavy ion fusion accelerators studies

    International Nuclear Information System (INIS)

    Eylon, S.; Henestroza, E.; Garvey, T.; Johnson, R.; Chupp, W.

    1991-04-01

    Low-emittance (high-brightness) Cs + thermionic sources were developed for the heavy ion induction linac experiment MBE-4 at LBL. The MBE-4 linac accelerates four 10 mA beams from 200 ke V to 900 ke V while amplifying the current up to a factor of nine. Recent studies of the transverse beam dynamics suggested that characteristics of the injector geometry were contributing to the normalized transverse emissions growth. Phase-space and current density distribution measurements of the beam extracted from the injector revealed overfocusing of the outermost rays causing a hollow density profile. We shall report on the performance of a 5 mA scraped beam source (which eliminates the outermost beam rays in the diode) and on the design of an improved 10 mA source. The new source is based on EGUN calculations which indicated that a beam with good emissions and uniform current density could be obtained by modifying the cathode Pierce electrodes and using a spherical emitting surface. The measurements of the beam current density profile on a test stand were found to be in agreement with the numerical simulations. 3 refs., 6 figs

  17. Operation and control of ion-exchange processes for treatment of radioactive wastes

    International Nuclear Information System (INIS)

    Emelity, L.A.

    1967-01-01

    A manual dealing with the application of ion-exchange materials to the treatment of radioactive wastes and reviewing the facilities currently using this method. This book is one of three commissioned by the IAEA on the principal methods of concentrating radioactive wastes. The content of this document is: (i) Historical review related to removal of radioactivity; (ii) Principles of ion exchange (iii) Ion-exchange materials; (iv) Limitations of ion exchangers; (v) Application of ion exchange to waste processing; (vi) Operational procedures and experiences; (vii) Cost-of-treatment by ion-exchange. The document also gives a list of producers of ion-exchange material and defines some relevant terms. 101 refs, 31 figs, 27 tabs

  18. Preparation of inorganic ion exchangers with high selectivity for lithium isotopes

    International Nuclear Information System (INIS)

    Oi, Takao

    2004-01-01

    Development of ion exchangers that show large lithium isotope effects is hoped for to establish highly efficient chromatographic processes of lithium isotope separation. In this paper, preparation, characterization, ion exchange properties, and lithium isotope selectivity of inorganic materials that have been and still are being studied by my research group at Sophia University are reviewed. They include manganese oxides-based ion exchangers, antimonic acids and titanium/zirconium phosphates-based ion exchangers. As a result, the lithium isotope separation effects that were one order of magnitude larger than those of organic ion exchangers were obtained. Some inorganic ion exchangers were found to show ion exchange rates more than comparable to those of organic ones. (author)

  19. Operation and control of ion-exchange processes for treatment of radioactive wastes

    Energy Technology Data Exchange (ETDEWEB)

    Emelity, L A [Los Alamos National Lab., NM (United States)

    1967-12-01

    A manual dealing with the application of ion-exchange materials to the treatment of radioactive wastes and reviewing the facilities currently using this method. This book is one of three commissioned by the IAEA on the principal methods of concentrating radioactive wastes. The content of this document is: (i) Historical review related to removal of radioactivity; (ii) Principles of ion exchange (iii) Ion-exchange materials; (iv) Limitations of ion exchangers; (v) Application of ion exchange to waste processing; (vi) Operational procedures and experiences; (vii) Cost-of-treatment by ion-exchange. The document also gives a list of producers of ion-exchange material and defines some relevant terms. 101 refs, 31 figs, 27 tabs.

  20. Characteristics of resin floc dispersion of anion and cation exchange resin in precoat filter using powdered ion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Adachi, Tetsurou (Nitto Denko Corp., Ibaraki, Osaka (Japan)); Sawa, Toshio; Shindoh, Toshikazu

    1989-09-01

    The filtration performance of mixed filter aid consisting of powdered anion and cation exchange resins used in the precoat filter is closely related to the characteristics of resin floc dispersion. The factors related to resin floc dispersion of anion and cation exchange resin were investigated by measuring the specific settle volume of resin floc as an evaluating index in addition to the measurement of physical, chemical and electrochemical properties of powdered ion exchange resin. The effect of adsorption of iron oxide and polymer electrolyte and of ion exchange were determined. In addition, considered floc dispersion with adsorbing iron oxide, it was assumed that the amount and filling ratio of resin floc were related to summation and multiplication of surface electric charge respectively. An experimental expression was obtained for simulation of the change of specific settle volume of resin floc by particle size, surface area, ion exchange capacity and degree of ionization of the powdered ion exchange resin. (author).

  1. Characteristics of resin floc dispersion of anion and cation exchange resin in precoat filter using powdered ion exchange resin

    International Nuclear Information System (INIS)

    Adachi, Tetsurou; Sawa, Toshio; Shindoh, Toshikazu.

    1989-01-01

    The filtration performance of mixed filter aid consisting of powdered anion and cation exchange resins used in the precoat filter is closely related to the characteristics of resin floc dispersion. The factors related to resin floc dispersion of anion and cation exchange resin were investigated by measuring the specific settle volume of resin floc as an evaluating index in addition to the measurement of physical, chemical and electrochemical properties of powdered ion exchange resin. The effect of adsorption of iron oxide and polymer electrolyte and of ion exchange were determined. In addition, considered floc dispersion with adsorbing iron oxide, it was assumed that the amount and filling ratio of resin floc were related to summation and multiplication of surface electric charge respectively. An experimental expression was obtained for simulation of the change of specific settle volume of resin floc by particle size, surface area, ion exchange capacity and degree of ionization of the powdered ion exchange resin. (author)

  2. Respective influence of thermodynamic, hydrodynamic and diffusion factors on ion exchanger operation. Application to the ion exchanger NYMPHEA

    International Nuclear Information System (INIS)

    Nicoud, R.M.

    1987-01-01

    Nymphea is an annular ion exchanger, with a resin bed 30 centimeter-thick, used for purification of the water from the spent fuel storage pool at La Hague reprocessing plant. Very low concentration solutions (10 -12 eq/l for cobalt) are purified by Nymphea, and parameter must be extrapolated from the range 0.01 - 0.0001 eq/l to very low concentrations. A model is developed, describing ion state inside the grains. The limiting step in Nymphea operation is external diffusion. Diffusion time is determined by mean grain size which should be accurately defined for extrapolation of results from monodispersed distribution (often the case in laboratories) to polydispersed (often the case in industry). Operation of an ion exchanger can be simulated for any ion number in solution. In steady state condition of concentration pool purification increases with flow rate. Simulation in transient operation allows the determination of all the concentrations in function of time and hence to calculate the time to reach the maximum permissible concentration for cobalt. This time depends upon calcium pollution (by fuel can dissolution, atmospheric pollution) which is not accurately known [fr

  3. Charge exchange spectroscopy as a fast ion diagnostic on TEXTOR

    International Nuclear Information System (INIS)

    Delabie, E.; Jaspers, R. J. E.; Hellermann, M. G. von; Nielsen, S. K.; Marchuk, O.

    2008-01-01

    An upgraded charge exchange spectroscopy diagnostic has been taken into operation at the TEXTOR tokamak. The angles of the viewing lines with the toroidal magnetic field are close to the pitch angles at birth of fast ions injected by one of the neutral beam injectors. Using another neutral beam for active spectroscopy, injected counter the direction in which fast ions injected by the first beam are circulating, we can simultaneously measure a fast ion tail on the blue wing of the D α spectrum while the beam emission spectrum is Doppler shifted to the red wing. An analysis combining the two parts of the spectrum offers possibilities to improve the accuracy of the absolute (fast) ion density profiles. Fast beam modulation or passive viewing lines cannot be used for background subtraction on this diagnostic setup and therefore the background has to be modeled and fitted to the data together with a spectral model for the slowing down feature. The analysis of the fast ion D α spectrum obtained with the new diagnostic is discussed.

  4. The adsorption of Sr(II) and Cs(I) ions by irradiated Saccharomyces cerevisiae

    International Nuclear Information System (INIS)

    Yiming Tan; Jundong Feng; Liang Qiu; Zhentian Zhao; Xiaohong Zhang; Haiqian Zhang

    2017-01-01

    Adsorption behavior and mechanism of Sr(II) and Cs(I) in single and binary solutions using irradiated Saccharomyces cerevisiae was investigated. The effects of several environmental factors on Sr(II) and Cs(I) adsorption to irradiated Saccharomyces cerevisiae was determined. The equilibrium experimental data were simulated by different kinetic models and isotherm models. The combined effect of Sr(II) and Cs(I) on Saccharomyces cerevisiae is generally antagonistic. SEM and EDS analyses indicate that crystals formed on the cell surface are precipitate of Sr(II) and Cs(I), respectively. (author)

  5. Ra/Ca separation by ion exchange chromatography

    International Nuclear Information System (INIS)

    Flores Mendoza, J.

    1990-01-01

    Ra/Ca separation by ion exchange. The objective of this work was to acquire knowledge of the chromatographic behaviour of the alkaline earth cations calcium, barium and radium and the obtention of well-defined alpha spectra of 226 Ra. Three cationic ion exchange resins (Dower 50 W-X8, AG 50W-XB and Merck I) and three complexing agents (ethylenediaminetetraacetic acid, citric acid and tartaric acid) at various pH values have been investigated. The three types of ions are fixed on the resins at pH 4.8; calcium is eluted at pH between 5 and 6 depending on the resin; barium and radium are eluted at pH values from 8 to 11. Radium is also eluted with a 2 M nitric acid solution, from which it can be electrodeposited on a stainless steel disk potassium fluoride as electrolyte at pH 14. The electrolysis is conducted for 18 hours with a current of mA. Under these conditions high resolution alpha spectra were obtained for 226 Ra, which was practically free from radioactive contaminants (Author)

  6. Study of the secondary negative ion emission of copper and several of its alloys by impact with Cs/sup +/ ions

    Energy Technology Data Exchange (ETDEWEB)

    Vallerand, P; Baril, M [Laval Univ., Quebec City (Canada). Dept. de Physique

    1977-07-01

    Secondary ion emission studies have been undertaken using Cs/sup +/ as the primary ion beam. A good vacuum (ca. 10/sup -8/ torr) is needed to eliminate contamination by residual gases. Negative ion emission of pure copper is compared with its alloys. The thermodynamic equilibrium model of Andersen is discussed. For low element concentrations, the experimental data show enhancement in negative emission of P, Al, Fe, Sn, Ni, and attenuation for Zn, Pb. The order of magnitude of ionic efficiency S/sup -/ for copper is evaluated at 10/sup -4/.

  7. Kinetic study of heavy metal ions removal by ion exchange in batch conical air spouted bed

    Directory of Open Access Journals (Sweden)

    T.M. Zewail

    2015-03-01

    Full Text Available Spouted bed contactor is a hybrid of fixed and fluidized bed contactors, which retains the advantages of each with good hydrodynamic conditions. The aim of the present study is to investigate the performance of a batch conical air spouted vessel for heavy metal removal by strong cation exchange resins (AMBERJET 1200 Na. The effect of various parameters such as type of heavy metal ions (Ni+2 and Pb+2, contact time, superficial air velocity and initial heavy metal ion concentration on % heavy metal ion removal has been investigated. It has been found that under optimum conditions 98% and 99% removal of Ni+2 and Pb+2 were achieved respectively. Several kinetic models were used to test the experimental data and to examine the controlling mechanism of the sorption process. The present results of Ni+2 and Pb+2 well fit pseudo second order kinetic model with a high correlation coefficient. Both film diffusion and intra-particle diffusion contribute to the ion exchange process. The present study revealed that spouted bed vessel may provide an effective alternative for conducting ion exchange reactions.

  8. Phosphate barrier on pore-filled cation-exchange membrane for blocking complexing ions in presence of non-complexing ions

    Science.gov (United States)

    Chavan, Vivek; Agarwal, Chhavi; Shinde, Rakesh N.

    2018-06-01

    In present work, an approach has been used to form a phosphate groups bearing surface barrier on a cation-exchange membrane (CEM). Using optimized conditions, the phosphate bearing monomer bis[2-(methacryloyloxy)ethyl] phosphate has been grafted on the surface of the host poly(ethersulfone) membranes using UV light induced polymerization. The detailed characterizations have shown that less than a micron layer of phosphate barrier is formed without disturbing the original microporous structure of the host membrane. The pores of thus formed membrane have been blocked by cationic-gel formed by in situ UV-initiator induced polymerization of 2-acrylamido-2-methyl-1-propane sulphonic acid along with crosslinker ethylene glycol dimethacrylate in the pores of the membrane. UV-initiator is required for pore-filling as UV light would not penetrate the interior matrix of the membrane. The phosphate functionalized barrier membrane has been examined for permselectivity using a mixture of representative complexing Am3+ ions and non-complexing Cs+ ions. This experiment has demonstrated that complex forming Am3+ ions are blocked by phosphate barrier layer while non-complexing Cs+ ions are allowed to pass through the channels formed by the crosslinked cationic gel.

  9. Nitrate and Perchlorate removal from groundwater by ion exchange; TOPICAL

    International Nuclear Information System (INIS)

    Burge, S; Halden, R

    1999-01-01

    This study was conducted to evaluate the performance of a small scale ion exchange unit (Krudico, Inc of Auborn, IA) for removal of nitrate and perchlorate from groundwater at Lawrence Livermore National Laboratory's Site 300. The unit was able to treat 3,600 gallons of Site 300 groundwater, at an average influent concentration of 100 mg/L NO(sub 3)(sup -) before breakthrough occurred. The unit contained 2.5 ft(sup 3) of Sybron SR-7 resin. Seventy gallons of regeneration waste were generated (water treated to waste ratio of 51:1). The effluent concentration was about 20 mg/L NO(sub 3)(sup -), which is equivalent to a treatment efficiency of at least 80%. There are several options for implementing this technology at Site 300. A target well, in the 817 area, has been selected. It has a 3 to 4 gpm flow rate, and concentrations of 90 mg/L NO(sub 3)(sup -) and 40(micro)g/L perchlorate. The different treatment options include ion exchange treatment of nitrate only, nitrate and perchlorate, or perchlorate only. Option 1: For the treatment of nitrate only, this unit will be able to treat 3,700 gallons of water before regeneration is required. If both columns of the ion exchange unit are used, 7,400 gallons could be treated before the columns will need to be regenerated (producing 140 gallons of waste, per cycle or every 1.5 days). The effluent nitrate concentration is expected to be about 17 mg/L. Annual operation and maintenance costs are estimated to be$0.14 per gallon of water treated. Option 2: If only perchlorate is to be removed with ion exchange at the 817 area, a smaller unit should be considered. A 55 gallon canister filled with ion exchange resin should be able to reduce perchlorate concentrations in the groundwater from 40(micro)g/L to non-detect levels for three years before the resin would need to be replaced. The contaminant-laden resin would be disposed of as hazardous waste. It is not practical to regenerate the resin because of the extreme difficulty of

  10. Electrochemical ion-exchange for medium active liquid waste treatment

    International Nuclear Information System (INIS)

    Bridger, N.J.; Turner, A.D.

    1987-01-01

    Electrochemical ion-exchange has already been demonstrated to be a robust, effective process for the treatment of active liquid wastes -with high decontamination and volume reduction factors, and only a low energy requirement. The primary aim of this new programme is to scale up this process - initially to 0.1m 3 /h, and ultimately to 1 3 m/h. A new 0.4m 2 electrode module has been designed and constructed, together with 3m 3 feed tanks for the first phase of this work. Further development work is also being carried out on alternative electrode designs and fabrication methods, as well as new exchange media (including inorganic absorbers and organic chelating resins) in order to optimize selectivity performance. (author)

  11. Ion exchange in ultramarine blue. Studies using radioactive tracers (1963)

    International Nuclear Information System (INIS)

    Goenvec, H.

    1963-05-01

    A study has been made of the exchange reaction between the constituent sodium in ultramarine blue, and silver in the form of a silver nitrate solution; an attempt hat been made to define the influence of the solvent of the silver nitrate on the kinetics of the exchange reaction. Five solvents have been used: water, methanol, ethanol, n-propanol and acetone. The reaction rates are controlled by a diffusion process inside the ultramarine grains, whatever the solvent used. It seems that the solvated ionic radius of the diffusing ion is one of the factors influencing the rate of reaction. Furthermore, the solvated ionic radius varies with temperature; this variation is different for each solvent and should explain the differences observed in the activation energies. (author) [fr

  12. Ion-Exchange Chromatography: Basic Principles and Application.

    Science.gov (United States)

    Cummins, Philip M; Rochfort, Keith D; O'Connor, Brendan F

    2017-01-01

    Ion-Exchange Chromatography (IEC) allows for the separation of ionizable molecules on the basis of differences in charge properties. Its large sample-handling capacity, broad applicability (particularly to proteins and enzymes), moderate cost, powerful resolving ability, and ease of scale-up and automation have led to it becoming one of the most versatile and widely used of all liquid chromatography (LC) techniques. In this chapter, we review the basic principles of IEC, as well as the broader criteria for selecting IEC conditions. By way of further illustration, we outline basic laboratory protocols to partially purify a soluble serine peptidase from bovine whole brain tissue, covering crude tissue extract preparation through to partial purification of the target enzyme using anion-exchange chromatography. Protocols for assaying total protein and enzyme activity in both pre- and post-IEC fractions are also described.

  13. Anisotropic exchange interaction for magnetic ion pairs in insulators

    International Nuclear Information System (INIS)

    Passeggi, M.C.G.

    1975-12-01

    The sources of possible contributions to the magnetic anisotropy for a pair of orbitally non degenerate magnetic ions are investigated. The problem being formulated with the help of the operator form of perturbation theory and irreducible tensor operators. Apart from the usual dipole-dipole effective interaction, mainly induced by the electronic spin-spin dipole coupling corrected by covalency, other mechanisms mediated by the spin-orbit coupling appear. These are a consequence of an appropriate description of the spin-orbit operators for a system which allows for delocalization of the magnetic electrons. A process similar to that known as pseudodipolar appears from contributions in which spin orbit combined with the Coulomb repulsion and with one-electron interactions (acting analogously as for the ''kinetic exchange'') produce compensating effects in third and fourth order, respectively. However, this effect does not appear to be describable in terms of the phenomenological exchange, as is usually assumed. (Passeggi, M.C.G.)

  14. TRIPLICATE SODIUM IODIDE GAMMA RAY MONITORS FOR THE SMALL COLUMN ION EXCHANGE PROGRAM

    Energy Technology Data Exchange (ETDEWEB)

    Couture, A.

    2011-09-20

    This technical report contains recommendations from the Analytical Development (AD) organization of the Savannah River National Laboratory (SRNL) for a system of triplicate Sodium Iodide (NaI) detectors to be used to monitor Cesium-137 ({sup 137}Cs) content of the Decontaminated Salt Solution (DSS) output of the Small Column Ion Exchange (SCIX) process. These detectors need to be gain stabilized with respect to temperature shifts since they will be installed on top of Tank 41 at the Savannah River Site (SRS). This will be accomplished using NaI crystals doped with the alpha-emitting isotope, Americium-241({sup 241}Am). Two energy regions of the detector output will be monitored using single-channel analyzers (SCAs), the {sup 137}Cs full-energy {gamma}-ray peak and the {sup 241}Am alpha peak. The count rate in the gamma peak region will be proportional to the {sup 137}Cs content in the DSS output. The constant rate of alpha decay in the NaI crystal will be monitored and used as feedback to adjust the high voltage supply to the detector in response to temperature variation. An analysis of theoretical {sup 137}Cs breakthrough curves was used to estimate the gamma activity expected in the DSS output during a single iteration of the process. Count rates arising from the DSS and background sources were predicted using Microshield modeling software. The current plan for shielding the detectors within an enclosure with four-inch thick steel walls should allow the detectors to operate with the sensitivity required to perform these measurements. Calibration, testing, and maintenance requirements for the detector system are outlined as well. The purpose of SCIX is to remove and concentrate high-level radioisotopes from SRS salt waste resulting in two waste streams. The concentrated high-level waste containing {sup 137}Cs will be sent to the Defense Waste Processing Facility (DWPF) for vitrification and the low-level DSS will be sent to the Saltstone Production Facility (SPF

  15. Triplicate Sodium Iodide Gamma Ray Monitors For The Small Column Ion Exchange Program

    International Nuclear Information System (INIS)

    Couture, A.

    2011-01-01

    This technical report contains recommendations from the Analytical Development (AD) organization of the Savannah River National Laboratory (SRNL) for a system of triplicate Sodium Iodide (NaI) detectors to be used to monitor Cesium-137 ( 137 Cs) content of the Decontaminated Salt Solution (DSS) output of the Small Column Ion Exchange (SCIX) process. These detectors need to be gain stabilized with respect to temperature shifts since they will be installed on top of Tank 41 at the Savannah River Site (SRS). This will be accomplished using NaI crystals doped with the alpha-emitting isotope, Americium-241( 241 Am). Two energy regions of the detector output will be monitored using single-channel analyzers (SCAs), the 137 Cs full-energy γ-ray peak and the 241 Am alpha peak. The count rate in the gamma peak region will be proportional to the 137 Cs content in the DSS output. The constant rate of alpha decay in the NaI crystal will be monitored and used as feedback to adjust the high voltage supply to the detector in response to temperature variation. An analysis of theoretical 137 Cs breakthrough curves was used to estimate the gamma activity expected in the DSS output during a single iteration of the process. Count rates arising from the DSS and background sources were predicted using Microshield modeling software. The current plan for shielding the detectors within an enclosure with four-inch thick steel walls should allow the detectors to operate with the sensitivity required to perform these measurements. Calibration, testing, and maintenance requirements for the detector system are outlined as well. The purpose of SCIX is to remove and concentrate high-level radioisotopes from SRS salt waste resulting in two waste streams. The concentrated high-level waste containing 137 Cs will be sent to the Defense Waste Processing Facility (DWPF) for vitrification and the low-level DSS will be sent to the Saltstone Production Facility (SPF) to be incorporated into grout.

  16. Properties of the Carboxylate ion exchange resins; Karboxylatjonbytarmassans egenskaper

    Energy Technology Data Exchange (ETDEWEB)

    Allard, Bert; Dario, Maarten [Oerebro Univ. (Sweden); Boren, Hans [Linkoepings Univ. (Sweden); Torstenfelt, Boerje [Swedpower, Stockholm (Sweden); Puigdomenech, Ignasi; Johansson, Claes [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    2002-09-01

    Weakly acidic, carboxylic resin has been selected, together with strong base anion resins, for water purification at the Forsmark 1 and 2 reactors. For the strong (but not the weak) ion exchange resin the Nuclear Power Inspectorate has given permission to dispose the spent resins in the SFR 1 (the Final Repository for Radioactive Operational Waste). This report gives a review of the carboxylic resins and comes to the conclusion that the resins are very stable and that there should not exist any risks for increased leaching of radionuclides from SFR 1 if these resins are disposed (compared to the strong resins)

  17. Incineration of ion exchange resins using concentric burners

    International Nuclear Information System (INIS)

    Fukasawa, T.; Chino, K.; Kawamura, F.; Kuriyama, O.; Yusa, H.

    1985-01-01

    A new incineration method, using concentric burners, is studied to reduce the volume of spent ion exchange resins generated from nuclear power plants. Resins are ejected into the center of a propane-oxygen flame and burned within it. The flame length is theoretically evaluated by the diffusion-dominant model. By reforming the burner shape, flame length can be reduced by one-half. The decomposition ratio decreases with larger resin diameters due to the loss of unburned resin from the flame. A flame guide tube is adapted to increase resin holding time in the flame, which improves the decomposition ratio to over 98 wt%

  18. Immobilization of ion-exchange resins in cement

    International Nuclear Information System (INIS)

    Howard, C.G.; Jolliffe, C.B.; Lee, D.J.

    1991-01-01

    The removal of activity from spent decontaminating solutions, can be achieved using organic ion-exchange resins. These resins can be successfully immobilized in cement-based matrices. The optimum cement system contained 10% ordinary Portland cement, 84% gg blast furnace slag, 6% microsilica with a water/cement ratio of 0.5 and a dry resin loading of 36% with respect to total weight. This formulation was successfully scaled up to 200 litres, giving a product with acceptable compressive strength, dimensional stability and elastic modulus. Storage of samples under water appears to have no detrimental effects on the product's properties. 26 tabs., 22 figs., 29 refs

  19. Immobilisation of ion exchange resins in cement: final report

    International Nuclear Information System (INIS)

    Howard, C.G.; Jolliffe, C.B.; Lee, D.J.

    1989-03-01

    The removal of activity from spent decontaminating solutions eg LOMI can be achieved using organic ion exchange resins. These resins can be successfully immobilised in cement based matrices. The optimum cement system contained 10% Ordinary Portland Cement 84% gg Blast Furnace Slag, 6% Microsilica with a water cement ratio of 0.5 and a dry resin loading of 36% with respect to total weight. This information was successfully scaled up to 200 litres giving a product with acceptable compressive strength, dimensional stability and elastic modulus. Storage of samples under water appears to have no detrimental effects on the product's properties. (author)

  20. Treatment of spent ion exchange resins IAEA research coordination programme

    International Nuclear Information System (INIS)

    Balu, K.; Bhatia, S.C.; Wattal, P.K.; Chanana, N.

    1981-09-01

    Spent ion-exchange resins arising from steam condensate systems, reactor coolant clean-up systems and rad-waste procession, are considered as a specific solid waste management problem. This is the second report on the product characterisation with respect to thermal properties, flammability, bio-organic degradation and leaching behaviours. All these studies are based on polyester-styrene polymer as a matrix for fixation of these spent Ix-resins. Choice of this matrix was dealt with in the first report. (author)

  1. Modified ion exchange resins - synthesis and properties. Pt. 1

    Energy Technology Data Exchange (ETDEWEB)

    Doescher, F.; Klein, J.; Pohl, F.; Widdecke, H.

    1982-01-22

    Sulfomethylated resins are prepared by polymer analogous reactions, starting from macroporous poly(styrene-co-divinylbenzene) matrices. Different reaction paths are discussed and used in the synthesis. Sulfomethylation can be achieved by reaction of a chloromethylated resin with dimethyl sulfide and sodium sulfonate or alternatively by oxidation of polymer-bound thiol groups. Both methods give high conversions as shown by IR spectra and titration of the sulfonic acid groups. Poly(1-(4-hydroxysulfomethylphenyl)ethylene) (3) is obtained by reaction of poly(1-(4-hydroxyphenyl)ethylene) (2) resin with formaldehyde/sodium sulfonate. The thermal stability, catalytic activity, and ion exchange equilibria of the sulfomethylated resin are investigated.

  2. Lead titanate nanotubes synthesized via ion-exchange method: Characteristics and formation mechanism

    International Nuclear Information System (INIS)

    Song Liang; Cao Lixin; Li Jingyu; Liu Wei; Zhang Fen; Zhu Lin; Su Ge

    2011-01-01

    Highlights: → Lead titanate nanotubes PbTi 3 O 7 were firstly synthesized by ion-exchange method. → Sodium titanate nanotubes have ion exchangeability. → Lead titanate nanotubes show a distinct red shift on absorption edge. - Abstract: A two-step method is presented for the synthesis of one dimensional lead titanate (PbTi 3 O 7 ) nanotubes. Firstly, titanate nanotubes were prepared by an alkaline hydrothermal process with TiO 2 nanopowder as precursor, and then lead titanate nanotubes were formed through an ion-exchange reaction. We found that sodium titanate nanotubes have ion exchangeability with lead ions, while protonated titanate nanotubes have not. For the first time, we distinguished the difference between sodium titanate nanotubes and protonated titanate nanotubes in the ion-exchange process, which reveals a layer space effect of nanotubes in the ion-exchange reaction. In comparison with sodium titanate, the synthesized lead titanate nanotubes show a narrowed bandgap.

  3. Ion-exchange equilibrium of N-acetyl-D-neuraminic acid on a strong anionic exchanger.

    Science.gov (United States)

    Wu, Jinglan; Ke, Xu; Zhang, Xudong; Zhuang, Wei; Zhou, Jingwei; Ying, Hanjie

    2015-09-15

    N-acetyl-D-neuraminic acid (Neu5Ac) is a high value-added product widely applied in the food industry. A suitable equilibrium model is required for purification of Neu5Ac based on ion-exchange chromatography. Hence, the equilibrium uptake of Neu5Ac on a strong anion exchanger, AD-1 was investigated experimentally and theoretically. The uptake of Neu5Ac by the hydroxyl form of the resin occurred primarily by a stoichiometric exchange of Neu5Ac(-) and OH(-). The experimental data showed that the selectivity coefficient for the exchange of Neu5Ac(-) with OH(-) was a non-constant quantity. Subsequently, the Saunders' model, which took into account the dissociation reactions of Neu5Ac and the condition of electroneutrality, was used to correlate the Neu5Ac sorption isotherms at various solution pHs and Neu5Ac concentrations. The model provided an excellent fit to the binary exchange data for Cl(-)/OH(-) and Neu5Ac(-)/OH(-), and an approximate prediction of equilibrium in the ternary system Cl(-)/Neu5Ac(-)/OH(-). This basic information combined with the general mass transfer model could lay the foundation for the prediction of dynamic behavior of fixed bed separation process afterwards. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Kinetic study of ion exchange in phosphoric acid chelating resin

    International Nuclear Information System (INIS)

    Brikci-Nigassa, Mounir; Hamouche, Hafida

    1995-11-01

    Uranium may be recovered as a by product of wet phosphoric acid using a method based on specific ion exchange resins. These resins called chelates contain amino-phosphonic functional groups. The resin studied in this work is a purolite S-940; uranium may be loaded on this resin from 30% P2O5 phosphoric acid in its reduced state. The influence of different parameters on the successive steps of the process have been studied in batch experiments: uranium reduction, loading and oxydation. Uranium may be eluted with ammonium carbonate and the resin regeneration may be done with hydrochloric acid.Ferric ions reduce the effective resin capacity considerably and inert fixation conditions are proposed to enhance uranium loading

  5. ION EXCHANGE SUBSTANCES BY SAPONIFICATION OF ALLYL PHOSPHATE POLYMERS

    Science.gov (United States)

    Kennedy, J.

    1959-04-14

    An ion exchange resin having a relatively high adsorption capacity tor uranyl ion as compared with many common cations is reported. The resin comprises an alphyl-allyl hydrogen phosphate polymer, the alphyl group being either allyl or a lower alkyl group having up to 5 carbon atoins. The resin is prepared by polymerizing compounds such as alkyl-diallyl phosphate and triallyl phosphate in the presence of a free radical generating substance and then partially hydrolyzing the resulting polymer to cause partial replacement of organic radicals by cations. A preferred free radical gencrating agent is dibenzoyl peroxide. The partial hydrolysis is brought about by refluxing the polymer with concentrated aqueous NaOH for three or four hours.

  6. The selectivity of zirconium phosphate for caesium in electrochemical ion exchange

    International Nuclear Information System (INIS)

    Lain, M.J.

    1988-11-01

    The properties of amorphous zirconium phosphate are investigated as an inorganic ion exchanger for use in liquid waste treatment by electrochemical ion exchange. Experiments to determine and increase the selectivity for caesium exchange over sodium are discussed, including various pulsed waveforms and studies with rotating membranes. Automation of a sampling system with pH and atomic absorption measurements is described. (author)

  7. The Cathodic Behavior of Ti(III) Ion in a NaCl-2CsCl Melt

    Science.gov (United States)

    Song, Yang; Jiao, Shuqiang; Hu, Liwen; Guo, Zhancheng

    2016-02-01

    The cathodic behavior of Ti(III) ions in a NaCl-2CsCl melt was investigated by cyclic voltammetry, chronopotentiometry, and square wave voltammetry with a tungsten electrode being the working electrode at different temperatures. The results show that the cathodic behavior of Ti(III) ion consists of two irreversible steps: Ti3+ + e = Ti2+ and Ti2+ + 2 e = Ti. The diffusion coefficient for the Ti(III) ion in the NaCl-2CsCl eutectic is 1.26 × 10-5 cm2 s-1 at 873 K (600 °C), increases to be 5.57 × 10-5 cm2 s-1 at 948K (675°C), and further rises to 10.8 × 10-5 cm2 s-1 at 1023 (750 °C). Moreover, galvanostatic electrolysis performed on a titanium electrode further presents the feasibility of electrodepositing metallic titanium in the molten NaCl-2CsCl-TiCl3 system.

  8. Rational Synthesis of Hollow Prussian Blue Analogue Through Coordination Replication and Controlled-Etching for Cs-Ion Removal.

    Science.gov (United States)

    Xu, Jun; Bu, Fan-Xing; Guo, Yi-Fei; Zhang, Wei; Hu, Ming; Jiang, Ji-Sen

    2018-05-01

    Radioactive cesium pollution have received considerable attention due to the increasing risks in development of the nuclear power plants in the world. Although various functional porous materials are utilized to adsorb Cs+ ions in water, Prussian blue analogues (PBAs) are an impressive class of candidates because of their super affinity of Cs+ ions. The adsorption ability of the PBAs strongly relate to the mesostructure and interstitial sites. To design a hollow PBA with large number of interstitial sites, the traditional hollowing methods are not suitable owing to the difficulty in processing the specific PBAs with large number of interstitial sites. In this work, we empolyed a rational strategy which was to form a "metal oxide"@"PBA" core-shell structure via coordination replication at first, then utilized a mild etching to remove the metal oxide core, led to hollow PBA finally. The obtained hollow PBAs were of high crystallinity and large number of interstitial sites, showing a super adsorption performance for Cs+ ions (221.6 mg/g) within a short period (10 min).

  9. Study of Aging ion exchange membranes used in separation processes

    International Nuclear Information System (INIS)

    Bellakhal, N.; Ghalloussi, R.; Dammak, L.

    2009-01-01

    Presently, the most important application of ion exchange membranes (IEM) is the electrodialysis. This technique consists of a membrane separation using a series of anion exchange membranes alternately and cations, often used for the desalination of brackish water. These membranes are confronted with problems of aging. Indeed, the more they are used more physical and chemical properties will change. A comparative study of the behavior of both EMI and new but the same treatment is carried out by measuring a magnitude transfer characteristic: ion permeability. Ionic permeability is a physical quantity can have an idea about the selectivity of the membrane towards the charged species and the p orosity o f the membrane. It is a transport of ions (cations + anions) through the membrane. Thus, determining the ion permeability is to determine the diffusion flux of a strong electrolyte through a membrane separating two compartments (one containing electrolytes and other water initially ultrapure who will gradually electrolyte through the membrane). The measurement technique used is that by conductimetric detection because of the ease of its implementation and its accuracy. Thus, the variation of the concentration of the electrolyte is continuously monitored by measuring the conductivity of the solution diluted with time. The curves s = f (t) MEA and MEC new and used varying concentration of the electrolyte membranes show that let in less waste of strong electrolyte (NaCl and HCl) than new ones. This can be explained by: - The functional sites are combined with polyvalent ions present even in trace amounts in the solution process and become inactive. The membrane loses its hydrophilic character and turns into a film almost hydrophobic. - The chemical attacks and electrodialysis operations have degraded and eliminated much of the fixed sites leading to the same effects on the hydrophilic membrane. - These two assumptions have been reinforced by the extent of exchange

  10. Incineration of ion-exchange resins in fluidized bed. Part of a coordinated programme on treatment of spent ion exchange resins

    International Nuclear Information System (INIS)

    Valkianinen, M.

    1980-10-01

    Incineration of ion-exchange resins in a fluidized bed was studied on the pilot plant scale. The test programme performed consisted of the testing of various bed materials and finding the optimal conditions of incineration of spent resins. Granular resins were incinerated in an ethanol-water mixture. Incinernation converts the organic resin into inert oxide material, which can be solidified for instance with cement. The weight of the ash was 1...20% and the volume 2...30% of the original resins, which contained 15...25% moisture. When solidified with cement the volume of the ash-concrete is 4...22% of the concrete of equal compressive strength acquired by direct solidification. Water immersion and heat tests of solidified ash showed satisfactory results. The absorption of Cs and Co in various bed materials was studied by means of inactive tracer materials. Biotite and chamotte absorbed significantly, but this absorption does not drastically help on the off gas side. The sintering of the bed materials in the presence of sodium was studied. Corundum, chamotte and biotite have a safety limit of 5% sodium of the bed's weight at 850 0 C

  11. Electrodeionization 1: migration of nickel ions absorbed in a rigid, macroporous cation-exchange resin

    NARCIS (Netherlands)

    Spoor, P.B.; Veen, ter W.R.; Janssen, L.J.J.

    2001-01-01

    The removal of nickel ions from a packed bed of ion-exchange material under an applied potential is studied. This process involves the use of an electrodialysis type cell in which the centre compartment is filled with a packed bed of ion-exchange particles. The bed width, concentration of nickel in

  12. Ion-Isotopic Exchange Reaction Kinetics using Anion Exchange Resins Dowex 550A LC and Indion-930A

    Directory of Open Access Journals (Sweden)

    P.U. Singare

    2014-06-01

    Full Text Available The present paper deals with the characterization of ion exchange resins Dowex 550A LC and Indion-930A based on kinetics of ion-isotopic exchange reactions for which the short lived radioactive isotopes 131I and 82Br were used as a tracers. The study was performed for different concentration of ionic solution varying from 0.001 mol/L to 0.004 mol/L and temperature in the range of 30.0 °C to 45.0 °C. The results indicate that as compared to bromide ion-isotopic exchange reaction, iodide exchange reaction take place at the faster rate. For both the ion-isotopic exchange reactions, under identical experimental conditions, the values of specific reaction rate increases with increase in the ionic concentration and decreases with rise in temperature. It was observed that at 35.00C, 1.000 g of ion exchange resins and 0.002 mol/L labeled iodide ion solution for iodide ion-isotopic exchange reaction, the values of specific reaction rate (min-1, amount of ion exchanged (mmol, initial rate of ion exchange (mmol/min and log Kd were 0.270, 0.342, 0.092 and 11.8 respectively for Dowex 550A LC resin, which was higher than the respective values of 0.156, 0.241, 0.038 and 7.4 as that obtained for Indion-930A resins. From the results, it appears that Dowex 550A LC resins show superior performance over Indion-930A resins under identical experimental conditions.

  13. Evaluation of Ion Exchange Materials in K Basin Floor Sludge and Potential Solvents for PCB Extraction from Ion Exchange Materials

    International Nuclear Information System (INIS)

    Schmidt, A.J.; Klinger, G.S.; Bredt, P.R.

    1998-01-01

    Approximately 73 m 3 of heterogeneous solid material, ''sludge,'' (upper bound estimate, Packer 1997) have accumulated at the bottom of the K Basins in the 100 K Area of the Hanford Site. This sludge is a mixture of spent fuel element corrosion products, ion exchange materials (organic and inorganic), graphite-based gasket materials, iron and aluminum metal corrosion products, sand, and debris (Makenas et al. 1996, 1997). In addition, small amounts of polychlorinated biphenyls (PCBs) have been found. These small amounts are significant from a regulatory standpoint. Ultimately, it is planned to transfer the K Basins sludge to the Hanford double shell tanks (DSTs). Chemical pretreatment is required to address criticality issues and the destruction or removal of PCBs before the K Basin sludge can be transferred to the DSTs. Eleven technologies have been evaluated (Papp 1997) as potential pretreatment methods. Based on the evaluations and engineering studies and limited testing, Fluor Daniel Hanford recommended solvent washing of the K Basin sludge, followed by nitric acid dissolution and, potentially, peroxide addition (FDH 1997). The solvent washing (extraction) and peroxide addition would be used to facilitate PCB removal and destruction. Following solvent extraction, the PCBs could be distilled and concentrated for disposal as a low-level waste. The purpose of the work reported here was to continue investigating solvent extraction, first by better identifying the ion exchange materials in the actual sludge samples and then evaluating various solvents for removing the PCBs or possibly dissolving the resins. This report documents some of the process knowledge on ion exchange materials used and spilled in the K Basins and describes the materials identified from wet sieving KE Basin floor and canister sludge and the results of other analyses. Several photographs are included to compare materials and illustrate material behavior. A summary of previous tests on solvent

  14. Magnetic Exchange Interactions and Estimation of TN in CsNiF3 from first principles

    Czech Academy of Sciences Publication Activity Database

    Legut, Dominik; Rusz, Ján

    2008-01-01

    Roč. 113, č. 1 (2008), s. 503-506 ISSN 0587-4246. [CSMAG'07. Košice, 09.07.2007-12.07.2007] R&D Projects: GA ČR GA106/07/1078 Institutional research plan: CEZ:AV0Z20410507; CEZ:AV0Z10100521 Keywords : exchange interactions * magnetism * Heisenberg model * 1D ferromagnet * Neel temperature Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.321, year: 2008

  15. Retention Behaviour of Copper, Zinc, Cadmium and Lead Ions on Synthesized Zirconium Titanate Ion Exchanger

    International Nuclear Information System (INIS)

    El-Naggar, I.M.; Abdel-Galil, E.A.; Moustafa, M.E.; Mahmoud, M.Y.

    2013-01-01

    Zr(IV) titanate as inorganic ion exchange material has been synthesized and utilized as the adsorbent for the removal of Cu 2+ , Zn 2+ , Cd 2+ and Pb 2+ ions from aqueous waste solutions. The experimental data were analyzed by Langmuir and Freundlich models of adsorption. The results suggest that the adsorption of the studied metals Cu 2+ , Zn 2+ , Cd 2+ and Pb 2+ ions on Zr(IV) titanate was favourable for the Freundlich isotherm more than Langmuir isotherm. The numerical values of 1/n for the studied metal ions were found to be smaller than the one (1/n L ) was found to be R L > 1 which confirmed that the prepared Zr(IV) titanate unfavourable the Langmuir isotherm. Based on the obtained results, practical separation experiments for the above mentioned cations on Zr(IV) titanate (ZrTi) column from aqueous waste solutions were carried out.

  16. Luminescent characteristic of the CsBr phosphor activated with Eu{sup 2+} and Mn{sup 2+} ions

    Energy Technology Data Exchange (ETDEWEB)

    Téllez-Flores, E., E-mail: bluedays8i@hotmail.com [Programa de Posgrado en Ciencias (Física), Departamento de Investigación en Física, Universidad de Sonora, Rosales y Blvd. Transversal S/N, 83000 Hermosillo, Son., México (Mexico); Aceves, R., E-mail: raceves@cifus.uson.mx [Centro de Investigación en Física, Universidad de Sonora, Apartado Postal 5-88, 83190 Hermosillo, Son., México (Mexico); Pérez-Salas, R., E-mail: rperez@cifus.uson.mx [Centro de Investigación en Física, Universidad de Sonora, Apartado Postal 5-88, 83190 Hermosillo, Son., México (Mexico); Camarillo, I., E-mail: as99@xanum.uam.mx [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, Delegación Iztapalapa, C.P. 09340 México D.F. (Mexico); Caldiño, U., E-mail: cald@xanum.uam.mx [Departamento de Física, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Col. Vicentina, Delegación Iztapalapa, C.P. 09340 México D.F. (Mexico)

    2013-12-15

    Spectra of excitation and emission were measured at RT and 15 K in crystals quenched (Q) of CsBr:Eu{sup 2+}, CsBr:Mn{sup 2+} and CsBr:Eu{sup 2+},Mn{sup 2+}. Emission bands at 444, 480, 520 and 570 nm with different relative intensities are generated in the samples after UV excitation. The blue band at 444 nm was ascribed with unknown clusters or aggregated centers (AC) of dipoles type Eu{sup 2+}–V{sub C}{sup −} and insulated dipole centers (IDC) like Eu{sup 2+}–O{sup 2−}. The bands at 480, 520 and 570 nm were assigned to Cs{sub 4}EuBr{sub 6} nanocrystals; AC containing MnBr{sub 4}{sup 2−} units in tetrahedral symmetry and another yet unidentified AC defect, respectively. In crystals of CsBr:Eu{sup 2+},Mn{sup 2+} the excitation and emission spectra taken at 15 K show no clear evidence of an energy transfer mechanism. Instead, the results suggest that the emission is produced by direct excitation of the ions of Eu{sup 2+} and Mn{sup 2+}. Accordingly, single- or double-doped CsBr crystals may contain the same type of defects, either AC and/or IDC. -- Highlights: • The PL consists of several overlapping bands in the entire visible region. • The emission bands were ascribed to dipoles, aggregated and nanocrystals of different nature. • No clear evidence of energy transfer, meaning Eu and Mn pairs are not formed. • The material shows potential characteristics for its use as LED to white emission.

  17. Ion exchangers in radioactive waste management: natural Iranian zeolites.

    Science.gov (United States)

    Nilchi, A; Maalek, B; Khanchi, A; Ghanadi Maragheh, M; Bagheri, A; Savoji, K

    2006-01-01

    Five samples of natural zeolites from different parts of Iran were chosen for this study. In order to characterize and determine their structures, X-ray diffraction and infrared spectrometry were carried out for each sample. The selective absorption properties of each zeolite were found by calculating the distribution coefficient (K(d)) of various simulated wastes which were prepared by spiking the radionuclides with (131)I, (99)Mo, (153)Sm, (140)La and (147)Nd. All the zeolite samples used in this study had extremely high absorption value towards (140)La; clinoptolite from Mianeh and analsite from Ghalehkhargoshi showed good absorption for (147)Nd; clinoptolite from Semnan and clinoptolite from Firozkoh showed high absorption for (153)Sm; mesolite from Arababad Tabas showed good absorption for (99)Mo; and finally mesolite from Arababad Tabas, clinoptolite from Semnan and clinoptolite from Firozkoh could be used to selectively absorb (131)I from the stimulated waste which was prepared. The natural zeolites chosen for these studies show a similar pattern to those synthetic ion exchangers in the literature and in some cases an extremely high selectivity towards certain radioactive elements. Hence the binary separation of radioactive elements could easily be carried out. Furthermore, these zeolites, which are naturally occurring ion exchangers, are viable economically and extremely useful alternatives in this industry.

  18. Radiation stability of sodium titanate ion exchange materials

    International Nuclear Information System (INIS)

    Kenna, B.T.

    1980-02-01

    Sodium titanate and sodium titanate loaded macroreticular resin are being considered as ion exchangers to remove 90 Sr and actinides from the large volume of defense waste stored at Hanford Site in Washington. Preliminary studies to determine the radiation effect on Sr +2 and I - capacity of these ion-exchange materials were conducted. Samples of sodium titanate powder, sodium titanate loaded macroreticular resin, as well as the nitrate form of macroreticular anion resin were irradiated with up to 2 x 10 9 Rads of 60 Co gamma rays. Sodium titanate cation capacity decreased about 50% while the sodium titanate loaded macroeticular resin displayed a dramatic decrease in cation capacity when irradiated with 10 8 -10 9 Rad. The latter decrease is tentatively ascribed to radiation damage to the organic portion which subsequently inhibits interaction with the contained sodium titanate. The anion capacity of both macroreticular resin and sodium titanate loaded macroreticular resin exhibited significant decreases with increasing radiation exposure. These results suggest that consideration should be given to the potential effects of radiation degradation if column regeneration is to be used. 5 figures, 2 tables

  19. Data quality objectives for Ion Exchange Module (IXM) disposition

    International Nuclear Information System (INIS)

    Choi, I.

    1995-01-01

    This Data Quality Objective (DQO) document presents the data needs and accuracy requirements for sampling ion exchange modules at the K Basins, 100 K Area, to determine if there is a hydrogen gas buildup within the modules. This document was produced by PNL, with the assistance of Neptune and Associates, and was partly funded (for facilitator) by DOE-HQ as a demonstration DQO for EM activities. PNL involved a number of PNL, WHC and support contract staff (including external technical consultants) in meetings to define the data needed, along with the necessary accuracy, to resolve issues associated with hydrogen accumulation in Ion Exchange Modules (IXMS) that were generated prior to July 1994 and only have one nuc-fil vent. IXMs generated after July 1994 have multiple nuc-fil vents and do not require sampling. PNL transmitted this DQO to WHC on January 31, 1995. This Supporting Document is to assure that the document is captured into the document retrieval system. WHC review focused on the acceptability of the technical conclusions such that the data collected will meet minimum operational, safety and environmental needs

  20. Synthesis of layered sodium lanthanum selenide through ion exchange reactions

    International Nuclear Information System (INIS)

    Butts, Laura J.; Strickland, Nicholas; Martin, Benjamin R.

    2009-01-01

    Layered hexagonal KLaSe2 (α-NaFeO 2 -type) was synthesized using the reactive flux method and analyzed by powder XRD to determine its lattice constants (space group R-3m, a = 4.40508(5) A, c = 22.7838(5) A). NaLaSe 2 , which normally crystallizes as a disordered rock salt structure with mixed Na+/La + 3 sites, was synthesized through a solid state ion exchange reaction at 585 deg. C from a 1:3 molar ratio mixture of KLaSe 2 :NaI. The product of this reaction was hexagonally layered NaLaSe 2 (space group R-3m, a = 4.3497(3) A, c = 20.808(2) A) isostructural to KLaSe 2 . This product was analyzed by comparison with members of the set of solid solutions Na (1-x) K (x) LaSe 2 to confirm that the extent ion exchange in this reaction was complete. Cubic (disordered) NaLaSe 2 was also reacted with KI to yield the poorly crystalline hexagonally layered product with the approximate formula Na 0.79 K 0.21 LaSe 2

  1. Low-level liquid waste decontamination by ion exchange

    International Nuclear Information System (INIS)

    Campbell, D.O.; Lee, D.D.; Dillow, T.A.

    1991-12-01

    Improved processes are being developed to treat contaminated liquid wastes that have been and continue to be generated at Oak Ridge National Laboratory. Both inorganic and organic ion-exchange methods have given promising results. Nickel and cobalt hexacyanoferrate(2) compounds are extremely selective for cesium removal, with distribution coefficients in excess of 10 6 and remarkable insensitivity to competition from sodium and potassium. They tend to lose effectiveness at pH > ∼11, but some formulations are useful for limited periods of time up to pH ∼13. Sodium titanate is selective for strontium removal at high pH. The separations are so efficient that simple batch processes can yield large decontamination factors while generating small volumes of solid waste. A resorcinol-based resin developed at the Savannah River Site gave superior cesium removal, compared with other organic ion exchangers; the distribution coefficient was limited primarily by competition from potassium and was nearly independent of sodium. The optimum pH was ∼12.5. It was much less effective for strontium removal, which was limited by competition from sodium. 8 refs., 6 figs., 9 tabs

  2. Junction Potentials Bias Measurements of Ion Exchange Membrane Permselectivity.

    Science.gov (United States)

    Kingsbury, Ryan S; Flotron, Sophie; Zhu, Shan; Call, Douglas F; Coronell, Orlando

    2018-04-17

    Ion exchange membranes (IEMs) are versatile materials relevant to a variety of water and waste treatment, energy production, and industrial separation processes. The defining characteristic of IEMs is their ability to selectively allow positive or negative ions to permeate, which is referred to as permselectivity. Measured values of permselectivity that equal unity (corresponding to a perfectly selective membrane) or exceed unity (theoretically impossible) have been reported for cation exchange membranes (CEMs). Such nonphysical results call into question our ability to correctly measure this crucial membrane property. Because weighing errors, temperature, and measurement uncertainty have been shown to not explain these anomalous permselectivity results, we hypothesized that a possible explanation are junction potentials that occur at the tips of reference electrodes. In this work, we tested this hypothesis by comparing permselectivity values obtained from bare Ag/AgCl wire electrodes (which have no junction) to values obtained from single-junction reference electrodes containing two different electrolytes. We show that permselectivity values obtained using reference electrodes with junctions were greater than unity for CEMs. In contrast, electrodes without junctions always produced permselectivities lower than unity. Electrodes with junctions also resulted in artificially low permselectivity values for AEMs compared to electrodes without junctions. Thus, we conclude that junctions in reference electrodes introduce two biases into results in the IEM literature: (i) permselectivity values larger than unity for CEMs and (ii) lower permselectivity values for AEMs compared to those for CEMs. These biases can be avoided by using electrodes without a junction.

  3. Plasma arc pyrolysis of radioactive ion exchange resin

    International Nuclear Information System (INIS)

    Pickles, C.A.; Toguri, J.M.

    1992-01-01

    This paper reports on two ion exchange resins (IRN 77 and IRN 78) which were pyrolysed in a plasma-arc furnace. Both continuous and batch tests were performed. Volume reduction ratios of 10 to 1 and 10 to 3.5 were achieved for IRN 78 and IRN 77 respectively. The product of the resin pyrolysis was a char which contained the radioactive elements such as cobalt. The off-gases consisted of mainly hydrogen and carbon monoxide. There was a relatively small amount of dust in the off-gases. At the present time radioactive ion exchange resign is being kept in storage. The volume of this waste is increasing and it is important that the volume be reduce. The volume reduction ratio should be of the order of ten-to-one. Also, it is required that the radioactive elements can be collected or fixed in a form which could easily be disposed of. Plasma arc treatment offers considerable potential for the processing of the waste

  4. Removal of Cs{sup +}, Sr{sup 2+}, and Co{sup 2+} ions from the mixture of organics and suspended solids aqueous solutions by zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Xiang Hong; Fang, Fang; Lu, Chun Hai [College of Nuclear Technology and Automation Engineering, Chengdu University of Technology, Chengdu (China); Zheng, Lei [Southwest University of Science and Technology, Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Mianyang (China)

    2017-04-15

    Serving as an excellent adsorbent and inorganic ion exchanger in the water purification field, zeolite 4A has in this work presented a strong capability for purifying radioactive waste, such as Sr{sup 2+}, Cs{sup +}, and Co{sup 2+} in water. During the processes of decontamination and decommissioning of suspended solids and organics in low-level radioactive wastewater, the purification performance of zeolite 4A has been studied. Under ambient temperature and neutral condition, zeolite 4A absorbed simulated radionuclides such as Sr{sup 2+}, Cs{sup +}, and Co{sup 2+} with an absorption rate of almost 90%. Additionally, in alkaline condition, the adsorption percentage even approached 98.7%. After conducting research on suspended solids and organics of zeolite 4A for the treatment of radionuclides, it was found that the suspended clay was conducive to absorption, whereas the absorption of organics in solution was determined by the species of radionuclides and organics. Therefore, zeolite 4A has considerable potential in the treatment of radioactive wastewater.

  5. Enhanced DOC removal using anion and cation ion exchange resins.

    Science.gov (United States)

    Arias-Paic, Miguel; Cawley, Kaelin M; Byg, Steve; Rosario-Ortiz, Fernando L

    2016-01-01

    Hardness and DOC removal in a single ion exchange unit operation allows for less infrastructure, is advantageous for process operation and depending on the water source, could enhance anion exchange resin removal of dissolved organic carbon (DOC). Simultaneous application of cationic (Plus) and anionic (MIEX) ion exchange resin in a single contact vessel was tested at pilot and bench scales, under multiple regeneration cycles. Hardness removal correlated with theoretical predictions; where measured hardness was between 88 and 98% of the predicted value. Comparing bench scale DOC removal of solely treating water with MIEX compared to Plus and MIEX treated water showed an enhanced DOC removal, where removal was increased from 0.5 to 1.25 mg/L for the simultaneous resin application compared to solely applying MIEX resin. A full scale MIEX treatment plant (14.5 MGD) reduced raw water DOC from 13.7 mg/L to 4.90 mg/L in the treated effluent at a bed volume (BV) treatment rate of 800, where a parallel operation of a simultaneous MIEX and Plus resin pilot (10 gpm) measured effluent DOC concentrations of no greater than 3.4 mg/L, even at bed volumes of treatment 37.5% greater than the full scale plant. MIEX effluent compared to simultaneous Plus and MIEX effluent resulted in differences in fluorescence intensity that correlated to decreases in DOC concentration. The simultaneous treatment of Plus and MIEX resin produced water with predominantly microbial character, indicating the enhanced DOC removal was principally due to increased removal of terrestrially derived organic matter. The addition of Plus resin to a process train with MIEX resin allows for one treatment process to remove both DOC and hardness, where a single brine waste stream can be sent to sewer at a full-scale plant, completely removing lime chemical addition and sludge waste disposal for precipitative softening processes. Published by Elsevier Ltd.

  6. Determination of {sup 135}Cs and {sup 137}Cs in environmental samples: A review

    Energy Technology Data Exchange (ETDEWEB)

    Russell, B.C., E-mail: ben.russell@npl.co.uk [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom); National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW (United Kingdom); Croudace, Ian W.; Warwick, Phil E. [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom)

    2015-08-26

    Radionuclides of caesium are environmentally important since they are formed as significant high yield fission products ({sup 135}Cs and {sup 137}Cs) and activation products ({sup 134}Cs and {sup 136}Cs) during nuclear fission. They originate from a range of nuclear activities such as weapons testing, nuclear reprocessing and nuclear fuel cycle discharges and nuclear accidents. Whilst {sup 137}Cs, {sup 134}Cs and {sup 136}Cs are routinely measurable at high sensitivity by gamma spectrometry, routine detection of long-lived {sup 135}Cs by radiometric methods is challenging. This measurement is, however, important given its significance in long-term nuclear waste storage and disposal. Furthermore, the {sup 135}Cs/{sup 137}Cs ratio varies with reactor, weapon and fuel type, and accurate measurement of this ratio can therefore be used as a forensic tool in identifying the source(s) of nuclear contamination. The shorter-lived activation products {sup 134}Cs and {sup 136}Cs have a limited application but provide useful early information on fuel irradiation history and have importance in health physics. Detection of {sup 135}Cs (and {sup 137}Cs) is achievable by mass spectrometric techniques; most commonly inductively coupled plasma mass spectrometry (ICP-MS), as well as thermal ionisation (TIMS), accelerator (AMS) and resonance ionisation (RIMS) techniques. The critical issues affecting the accuracy and detection limits achievable by this technique are effective removal of barium to eliminate isobaric interferences arising from {sup 135}Ba and {sup 137}Ba, and elimination of peak tailing of stable {sup 133}Cs on {sup 135}Cs. Isobaric interferences can be removed by chemical separation, most commonly ion exchange chromatography, and/or instrumental separation using an ICP-MS equipped with a reaction cell. The removal of the peak tailing interference is dependent on the instrument used for final measurement. This review summarizes and compares the analytical procedures

  7. Studies of the hydrous titanium oxide ion exchanger. 4. Rate of the isotopic exchange of sodium ions between the exchanger in the Na+ form and aqueous solution

    International Nuclear Information System (INIS)

    Inoue, Yasushi; Yamazaki, Hiromichi; Kasuga, Fuminori

    1995-01-01

    The isotopic exchange rate of Na + between hydrous titanium(IV) oxides, precipitated at pH 6 and 13, in the Na + form and aqueous solution of sodium salt was determined radiochemically. The rate in the exchanger precipitated at pH 6 is controlled by the diffusion of Na + in the exchanger particles (particle diffusion). The diffusion coefficient and its activation energy are 1.9 x 10 -11 m 2 s -1 (pH 12, 5.0degC) and 29 kJ mol -1 (pH 12), respectively. The rate in the exchanger precipitated at pH 13 is also controlled by the particle diffusion. The rate is much slower than that in the other; this can be explained by assuming the existence of two kinds of independently diffusing ions (fast and slow species) in the exchanger. The diffusion coefficients are of the order of 10 -12 and 10 -13 m 2 s -1 for the fast and the slow species, respectively. Their activation energies are 48-60 kJ mol -1 at pH 12. The marked difference in kinetics between two exchanges was interpreted in terms of the difference in the acid-base property and in the microstructure of the matrix. (author)

  8. Application of ion-exchange unit in uranium extraction process in China (to be continued)

    International Nuclear Information System (INIS)

    Gong Chuanwen

    2004-01-01

    The application conditions of five different ion exchange units in uranium milling plant and wastewater treatment plant of uranium mine in China are introduced, including working parameters, existing problems and improvements. The advantages and disadvantages of these units are reviewed briefly. The procedure points to be followed in selecting ion exchange unit are recommended in the engineering design. The primary views are presented upon the application prospects of some ion exchange units in uranium extraction process in China

  9. Safety analysis report for packaging (onsite) for the Waste Encapsulation and Storage Facility ion exchange module

    International Nuclear Information System (INIS)

    Romano, T.

    1997-01-01

    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

  10. Salt-Zeolite Ion Exchange Equilibrium Studies for Complete Set of Fission Products in Molten LiCl-KCl

    International Nuclear Information System (INIS)

    Yoo, Tae-Sic; Frank, Steven M.; Simpson, Michael F.; Hahn, Paula A.; Battisti, Terry J.; Phongikaroon, Supathorn

    2010-01-01

    This paper presents results on LiCl-KCl based molten salts/zeolite-A contact experiments and the associated equilibrium ion exchange model. Experiments examine the contact behaviors of various ternary salts (LiCl-KCl-YCl3, LiCl-KCl-LaCl3, and LiCl-KCl-PrCl3) and quaternary salts (LiCl-KCl-CsCl-NdCl3 and LiCl-KCl-CsCl-SrCl2) with the zeolite-A. The developed equilibrium model assumes that there are ion exchange and occlusion sites, both of which are in equilibrium with the molten salt phase. A systematic approach in estimating total occlusion capacity of the zeolite-A is developed. The parameters of the model, including the total occlusion capacity of the zeolite-A, were determined from fitting experimental data collected via multiple independent studies including the ones reported in this paper. Experiments involving ternary salts were used for estimating the parameters of the model, while those involving quaternary salts were used to validate the model.

  11. Unravelling the secrets of Cs controlled secondary ion formation: Evidence of the dominance of site specific surface chemistry, alloying and ionic bonding

    Science.gov (United States)

    Wittmaack, Klaus

    2013-03-01

    Exposure of ion bombarded solids to Cs gives rise to a very strong enhancement of the yields of negatively charged secondary ions and, concurrently, to a lowering of positive ion yields. The phenomena have been explored in a large number of experimental and theoretical studies but attempts to clarify the mechanism of ion formation were not as successful as assumed. This review examines the state of the art in Cs controlled secondary ion mass spectrometry (SIMS) in great detail, with due consideration of low-energy alkali-ion scattering. In very basic studies on alkali induced secondary ion yield changes, sub-monolayer quantities of Cs or Li were deposited on the sample surface, followed by low-fluence ion bombardment, to avoid significant damage. If SIMS is applied to characterise the composition of solid materials, the simplest approach to achieving sample erosion as well as high negative-ion yields is bombardment with primary ions of Cs. Two other methods of sample loading with Cs provide more flexibility, (i) exposure to a collimated beam of Cs vapour and concurrent bombardment with high-energy non-Cs ions and (ii) the mixed-beam approach involving quasi-simultaneous bombardment with Cs and Xe ions. Both concepts have the advantage that undesirable sample overload with Cs can be avoided. High Cs concentrations reduce the formation probability of target specific molecular ions and lower the yields of all types of positive secondary ions, including Cs+, M+, X+, MCs+ and XCs+ (M and X denoting matrix and impurity elements). Quantitative SIMS analysis using MCs+ and XCs+ ions appears feasible, provided the Cs coverage is kept below about 5%. The semi-classical model of resonant charge transfer, also known as the tunnelling model, has long been considered a solid framework for the interpretation of Cs and Li based SIMS data. The model predicts ionisation probabilities for cases in which, at shallow distances from the surface, the affinity (ionisation) level of the

  12. Ion exchange removal of cesium from Hanford tank waste supernates with SuperLigR 644 resin

    International Nuclear Information System (INIS)

    Hassan, N.M.; McCabe, D.J.; King, W.D.; Hamm, L.L.

    2002-01-01

    SuperLig R 644 ion exchange resin is currently being evaluated for cesium ( 137 Cs) removal from radioactive Hanford tank waste supernates as part of the River Protection Project. Testing was performed with actual Hanford tank wastes of widely different compositions using two identical ion exchange columns connected in series each containing approximately 5.5-6.5 ml of SuperLig R 644 resin. The ion exchange columns utilized the same resin material that was eluted between the column tests. This was done to demonstrate the performance of the SuperLig R 644 resin for cesium removal from waste samples of different compositions, determine the loading and elution profiles, and to validate design assumptions for full-scale column performances. Decontaminated product solutions generated at the same operating temperature and constant residence times (bed volumes per hour) exhibited the same chemical compositions as their feed samples. The compositions of eluate solutions were generally as expected with the exception of uranium and total organic carbon, which where concentrated by the resin. Development of a pretreatment method for the SuperLig R 644 resin has been critical to successful column operation with different waste solutions. (author)

  13. Asymptotically exact calculation of the exchange energies of one-active-electron diatomic ions with the surface integral method

    International Nuclear Information System (INIS)

    Scott, Tony C; Aubert-Frecon, Monique; Hadinger, Gisele; Andrae, Dirk; Grotendorst, Johannes; III, John D Morgan

    2004-01-01

    We present a general procedure, based on the Holstein-Herring method, for calculating exactly the leading term in the exponentially small exchange energy splitting between two asymptotically degenerate states of a diatomic molecule or molecular ion. The general formulae we have derived are shown to reduce correctly to the previously known exact results for the specific cases of the lowest Σ and Π states of H + 2 . We then apply our general formulae to calculate the exchange energy splittings between the lowest states of the diatomic alkali cations K + 2 , Rb + 2 and Cs + 2 , which are isovalent to H + 2 . Our results are found to be in very good agreement with the best available experimental data and ab initio calculations

  14. Ion Exchange Column Tests Supporting Technetium Removal Resin Maturation

    Energy Technology Data Exchange (ETDEWEB)

    Nash, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); McCabe, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hamm, L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Smith, F. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Morse, M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2013-12-20

    The primary treatment of the tank waste at the DOE Hanford site will be done in the Waste Treatment and Immobilization Plant, currently under construction. The baseline plan for this facility is to treat the waste, splitting it into High Level Waste (HLW) and Low Activity Waste (LAW). Both waste streams are then separately vitrified as glass and sealed in canisters. The LAW glass will be disposed on site. There are currently no plans to treat the waste to remove technetium, so its disposition path is the LAW glass. Due to the soluble properties of pertechnetate and long half-life of 99Tc, effective management of 99Tc is important. Options are being explored to immobilize the supplemental LAW portion of the tank waste, as well as to examine the volatility of 99Tc during the vitrification process. Removal of 99Tc, followed by off-site disposal has potential to reduce treatment and disposal costs. A conceptual flow sheets for supplemental LAW treatment and disposal that could benefit from technetium removal will specifically examine removing 99Tc from the LAW feed stream to supplemental immobilization. SuperLig® 639 is an elutable ion exchange resin. In the tank waste, 99Tc is predominantly found in the tank supernate as pertechnetate (TcO4-). Perrhenate (ReO4-) has been shown to be a good non-radioactive surrogate for pertechnetate in laboratory testing for this ion exchange resin. This report contains results of experimental ion exchange distribution coefficient and column resin maturation kinetics testing using the resin SuperLig® 639a to selectively remove perrhenate from simulated LAW. This revision includes results from testing to determine effective resin operating temperature range. Loading tests were performed at 45°C, and the computer modeling was updated to include the temperature effects. Equilibrium contact testing indicated that this batch of

  15. Small Column Ion Exchange Design and Safety Strategy

    International Nuclear Information System (INIS)

    Huff, T.; Rios-Armstrong, M.; Edwards, R.; Herman, D.

    2011-01-01

    Small Column Ion Exchange (SCIX) is a transformational technology originally developed by the Department of Energy (DOE) Environmental Management (EM-30) office and is now being deployed at the Savannah River Site (SRS) to significantly increase overall salt processing capacity and accelerate the Liquid Waste System life-cycle. The process combines strontium and actinide removal using Monosodium Titanate (MST), Rotary Microfiltration, and cesium removal using Crystalline Silicotitanate (CST, specifically UOP IONSIV(reg s ign)IE-911 ion exchanger) to create a low level waste stream to be disposed in grout and a high level waste stream to be vitrified. The process also includes preparation of the streams for disposal, e.g., grinding of the loaded CST material. These waste processing components are technically mature and flowsheet integration studies are being performed including glass formulations studies, application specific thermal modeling, and mixing studies. The deployment program includes design and fabrication of the Rotary Microfilter (RMF) assembly, ion-exchange columns (IXCs), and grinder module, utilizing an integrated system safety design approach. The design concept is to install the process inside an existing waste tank, Tank 41H. The process consists of a feed pump with a set of four RMFs, two IXCs, a media grinder, three Submersible Mixer Pumps (SMPs), and all supporting infrastructure including media receipt and preparation facilities. The design addresses MST mixing to achieve the required strontium and actinide removal and to prevent future retrieval problems. CST achieves very high cesium loadings (up to 1,100 curies per gallon (Ci/gal) bed volume). The design addresses the hazards associated with this material including heat management (in column and in-tank), as detailed in the thermal modeling. The CST must be size reduced for compatibility with downstream processes. The design addresses material transport into and out of the grinder and

  16. Fine structure of excitons and electron-hole exchange energy in polymorphic CsPbBr3 single nanocrystals.

    Science.gov (United States)

    Ramade, Julien; Andriambariarijaona, Léon Marcel; Steinmetz, Violette; Goubet, Nicolas; Legrand, Laurent; Barisien, Thierry; Bernardot, Frédérick; Testelin, Christophe; Lhuillier, Emmanuel; Bramati, Alberto; Chamarro, Maria

    2018-04-05

    All inorganic CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) belong to the novel class of confined metal-halide perovskites which are currently arousing enthusiasm and stimulating huge activity across several fields of optoelectronics due to outstanding properties. A deep knowledge of the band-edge excitonic properties of these materials is thus crucial to further optimize their performances. Here, high-resolution photoluminescence (PL) spectroscopy of single bromide-based NCs reveals the exciton fine structure in the form of sharp peaks that are linearly polarized and grouped in doublets or triplets, which directly mirror the adopted crystalline structure, tetragonal (D4h symmetry) or orthorhombic (D2h symmetry). Intelligible equations are found that show how the fundamental parameters (spin-orbit coupling, ΔSO, crystal field term, T, and electron-hole exchange energy, J) rule the energy spacings in doublets and triplets. From experimental data, fine estimations of each parameter are obtained. The analysis of the absorption spectra of an ensemble of NCs with a "quasi-bulk" behavior leads to ΔSO = 1.20 ± 0.06 eV and T = -0.34 ± 0.05 eV in CsPbBr3. The study of individual luminescence responses of NCs having sizes comparable to the exciton Bohr diameter, 7 nm, allows us to estimate the value of J to be around ≈3 meV in both tetragonal and orthorhombic phases. This value is already enhanced by confinement.

  17. The novel composite mechanism of ammonium molybdophosphate loaded on silica matrix and its ion exchange breakthrough curves for cesium

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Hao [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Li, Yuxiang, E-mail: superfigure@163.com [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); National Defense Key Discipline Laboratory for Nuclear Wastes and Environmental Safety, Southwest University of Science and Technology, Mianyang 621010 (China); Wu, Lang [State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Ma, Xue [School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China)

    2017-02-15

    Highlights: • The granular composites were fabricated by the sequential annealing mechanism. • The method controls the porous characteristics and stable structure of materials. • The breakthrough curve of Cs{sup +} follows the Thomas model with a high removal rate. • It is a probable for SM-AMP20 to recycle Cs{sup +} using an eluent of 2–3 mol/L NH{sub 4}NO{sub 3}. - Abstract: Long-lived {sup 137}Cs (over 30 years), a byproduct of the spent fuel fission processes, comprises the majority of high-level and prolific heat-generating waste in downstream processing. This study reports a novel sequential annealing mechanism with cross-linked network of polyvinyl alcohol, fabricating the composite of ammonium molybdophosphate loaded on silica matrix (SM-AMP20, 20 wt% AMP) as an excellent granular ion exchanger for removal Cs{sup +}. When the matrix is remarkably sequential annealed, well-dispersed SM-AMP20 particles are formed by firmly anchoring themselves on controlling the porous characteristics and stable structure. The material crystallizes in the complex cubic space group Pn-3m with cell parameters of crystalline AMP formation. The breakthrough curve of Cs{sup +} by SM-AMP20 follows the Thomas model with a high removal rate of 88.23% (∼10 mg/L of Cs{sup +}) and breakthrough time as high as 26 h (flow rate Q ≈ 2.5 mL/min and bed height Z ≈ 11 cm) at neutral pH. We also report on sorbents that could efficiently remove Cs{sup +} ions from complex solutions containing different competitive cations (Na{sup +}, Al{sup 3+}, Fe{sup 3+}, and Ni{sup 2+}, respectively) in large excess. Furthermore, this study shows that there is a probability for SM-AMP20 to recycle cesium using an eluent of 2–3 mol/L NH{sub 4}NO{sub 3} solution.

  18. Development of Electrically Switched Ion Exchange Process for Selective Ion Separations

    International Nuclear Information System (INIS)

    Rassat, Scot D.; Sukamto, Johanes H.; Orth, Rick J.; Lilga, Michael A.; Hallen, Richard T.

    1999-01-01

    The electrically switched ion exchange (ESIX) process, being developed at Pacific Northwest National Laboratory, provides an alternative separation method to selectively remove ions from process and waste streams. In the ESIX process, in which an electroactive ion exchange film is deposited onto a high surface area electrode, uptake and elution are controlled directly by modulating the electrochemical potential of the film. This paper addresses engineering issues necessary to fully develop ESIX for specific industrial alkali cation separation challenges. The cycling and chemical stability and alkali cation selectivity of nickel hexacyanoferrate (NiHCF) electroactive films were investigated. The selectivity of NiHCF was determined using cyclic voltammetry and a quartz crystal microbalance to quantify ion uptake in the film. Separation factors indicated a high selectivity for cesium and a moderate selectivity for potassium in high sodium content solutions. A NiHCF film with improved redox cycling and chemical stability in a simulated pulp mill process stream, a targeted application for ESIX, was also prepared and tested

  19. Electrodialysis-ion exchange for the separation of dissolved salts

    International Nuclear Information System (INIS)

    Baroch, C.J.; Grant, P.J.

    1995-01-01

    The Department of Energy generates and stores a significant quantity of low level, high level, and mixed wastes. As some of the DOE facilities are decontaminated and decommissioned, additional and possibly different forms of wastes will be generated. A significant portion of these wastes are aqueous streams containing acids, bases, and salts, or are wet solids containing inorganic salts. Some of these wastes are quite dilute solutions, whereas others contain large quantities of nitrates either in the form of dissolved salts or acids. Many of the wastes are also contaminated with heavy metals, radioactive products, or organics. Some of these wastes are in storage because a satisfactory treatment and disposal processes have not been developed. This report describes the process of electrodialysis-ion exchange (EDIX) for treating aqueous wastes streams consisting of nitrates, sodium, organics, heavy metals, and radioactive species

  20. Ion exchange resins for water purification : properties and characterisation

    International Nuclear Information System (INIS)

    Gokhale, A.S.; Mathur, P.K.; Venkateswarlu, K.S.

    1987-01-01

    The report is divided into three sections. The first section contains a general introduction to ion exchange resins used in various processes, the second section describes characteristic properties of the polymer materials and the inter relation between them. This will, in turn, be useful to interpret the data obtained from the various tests carried out on the resins in the laboratory. In the third section of the report, are given the details of each method used for a particular test to be carried out on a routine basis. Each method describes the principle involved, the reagents and apparatus used in the experiment, the actual procedure and calculations and recording of the data. 3 refs. (author)

  1. Design of an ion exchange column for plutonium recovery

    International Nuclear Information System (INIS)

    Araujo, J.A. de; Matsuda, H.T.; Santos Tome Lobao, A. dos; Quesada, A.C.

    1994-01-01

    An ion exchange column design for plutonium recovering from scraps of the MOX fuel elements fabrication is presented. The proposed column is constructed in 304 stainless steel and borosilicate glass provided of heating-jacket and temperature control and pressure relief devices. Safety aspects required for alpha emitters handling have been also considered. The design and construction were performed totally at Brazilian Institute for Energetic and Nuclear Research. The equipment will be used in the plutonium separation step as a part of an installation named Facilidad Alfa at the Centro Atomico de Constituyentes-CNEA/Buenos Aires, where other processes, including dissolution denitration by microwaves and final steps of MOX pellets re-fabrication will be performed. (author). 4 refs, 3 figs

  2. Bovine plasma protein fractionation by ion exchange chromatography.

    Science.gov (United States)

    Moure, F; Rendueles, M; Díaz, M

    2004-12-01

    An ion exchange chromatography process was developed to separate the main protein fractions of bovine blood plasma using a composite material, Q-HyperD resin, and a gel material, DEAE-Sepharose. The experiments were carried out at semipreparative scale. It was necessary to establish analytical methods of electrophoresis and HPLC to identify the fractionated proteins. Results show that these materials are able to adequately fractionate different protein groups from the raw blood plasma. This method may be used to avoid chemical fractionation using agents such as ethanol or PEG and, thus, decrease protein denaturation of the different fractions to be used for research or pharmaceutical purposes. The Q-HyperD resin presents a better retention capacity for plasma protein than DEAE-Sepharose under the experimental conditions employed.

  3. Volume reduction of ion exchange resin by a pyrolysis technique

    International Nuclear Information System (INIS)

    Matsuda, M.; Funabashi, K.; Uchida, S.; Kikuchi, M.

    1985-01-01

    Volume reduction techniques, such as incineration and acid digestion, of spent ion exchange resins from nuclear power plants are being developed with a view toward reducing radioactive waste volume and also making the final waste form more stable. The authors chose pyrolysis as a technique that can be done at low operating temperatures and low gas flow rates in a reactor vessel. Fundamental experiments were performed to clarify the resin pyrolysis characteristics, and the optimum pyrolysis temperature was determined. Consequently, a pilot plant with a treatment capacity of approx. 50 kg/batch was constructed based on the results. Using the pilot plant, the authors are now performing pyrolysis of the resins and solidification of their residues. This report will give the results of fundamental experiments and pilot plant tests

  4. Advances in the disposal of radioactive ion exchange resins

    International Nuclear Information System (INIS)

    McCoy, S.B.

    1983-01-01

    During the last several years, more stringent regulations have been imposed on the disposal of low-level radioactive wastes. In particular, the disposal of high-activity ion exchange resins has been affected by the recent requirements intended to enhance waste stability. High-activity resins must now be either solidified or placed in a ''high-integrity'' container. The allowable levels of free liquids in the containers have also been reduced. Solidification of resins has long been applied at nuclear power stations, but new designs in high-integrity containers and dewatering techniques to enhance the waste stability and ensure regulatory compliance have been developed and are being introduced for use at power stations

  5. Ion exchange and adsorption in nuclear chemical engineering

    International Nuclear Information System (INIS)

    Schultz, W.W.; Wheelwright, E.J.; Godbee, H.; Mallory, C.W.; Burney, G.A.; Wallace, R.M.

    1983-01-01

    The nuclear industry involves a number of operations. Uranium ore must first be mined and the uranium recovered from the ore, purified, and concentrated. After the uranium has been enriched and fabricated into fuel elements, it is placed in nuclear reactors where it produces energy, fission products, and transmutation products. Finally, if the fuel cycle is completed, the uranium and useful transmutation products are recovered and separated from each other as well as from the fission products. The uranium may be recycled or used elsewhere, while most of the fission products become waste. Ion exchange finds use in nearly every part of the nuclear fuel cycle; these uses are the subject of this paper

  6. Electrodialysis-ion exchange for the separation of dissolved salts

    Energy Technology Data Exchange (ETDEWEB)

    Baroch, C.J. [Wastren, Inc., Westminster, CO (United States); Grant, P.J. [Wastren, Inc., Hummelstown, PA (United States)

    1995-10-01

    The Department of Energy generates and stores a significant quantity of low level, high level, and mixed wastes. As some of the DOE facilities are decontaminated and decommissioned, additional and possibly different forms of wastes will be generated. A significant portion of these wastes are aqueous streams containing acids, bases, and salts, or are wet solids containing inorganic salts. Some of these wastes are quite dilute solutions, whereas others contain large quantities of nitrates either in the form of dissolved salts or acids. Many of the wastes are also contaminated with heavy metals, radioactive products, or organics. Some of these wastes are in storage because a satisfactory treatment and disposal processes have not been developed. There is considerable interest in developing processes that remove or destroy the nitrate wastes. Electrodialysis-Ion Exchange (EDIX) is a possible process that should be more cost effective in treating aqueous waste steams. This report describes the EDIX process.

  7. Viscosity calculations of simulated ion-exchange resin waste glasses

    International Nuclear Information System (INIS)

    Kim, Cheon Woo; Park, Jong Kil; Lee, Kyung Ho; Lee, Myung Chan; Song, Myung Jae; BRUNELOT, Pierre

    2000-01-01

    An induction cold crucible melter (CCM) located in the NETEC-KEPCO has been used to vitrify simulated ion-exchange resin. During vitrification, the CCM operations were tightly constrained by glass viscosity as an important process parameter. Understanding the role of viscosity and quantifying viscosity is highly required in the determination of optimized feed formulations and in the selection of the processing temperature. Therefore, existing process models of glass viscosity based on a relationship between the glass composition, its structure polymerization, and the temperature were searched and adapted to our borosilicate glass systems. Calculated data using a viscosity model based on calculation of non-bridging oxygen (NBO) were in good agreement with the measured viscosity data of benchmark glasses

  8. Design of systems for handling radioactive ion exchange resin beads

    International Nuclear Information System (INIS)

    Shapiro, S.A.; Story, G.L.

    1979-01-01

    The flow of slurries in pipes is a complex phenomenon. There are little slurry data available on which to base the design of systems for radioactive ion exchange resin beads and, as a result, the designs vary markedly in operating plants. With several plants on-line, the opportunity now exists to evaluate the designs of systems handling high activity spent resin beads. Results of testing at Robbins and Meyers Pump Division to quantify the behavior of resin bead slurries are presented. These tests evaluated the following slurry parameters; resin slurry velocity, pressure drop, bead degradation, and slurry concentration effects. A discussion of the general characteristics of resin bead slurries is presented along with a correlation to enable the designer to establish the proper flowrate for a given slurry composition and flow regime as a function of line size. Guidelines to follow in designing a resin handling system are presented

  9. Manifestation of exchange effects in heavy-ion interactions

    International Nuclear Information System (INIS)

    Igashov, S. Yu.; Tchuvil’sky, Yu. M.

    2011-01-01

    Three different approaches to taking into account exchange effects in heavy-ion collisions are studied. Within the first of them, the lowest eigenstates of the Hamiltonian are treated as forbidden states. In the second approach, the eigenstates of the normalization kernel of the resonating-group model that correspond to zero eigenvalues are treated as forbidden states. The third approach takes additionally into account semiforbidden states. The 16 O + 16 O system is considered. A hybrid approach that combines the methods of discrete and continuous mathematics is developed for calculating the widths of narrow resonance states. The resonance width calculated within the approach that takes into account semiforbidden states proves to be sharply different from the widths obtained within traditional approaches.

  10. Open-framework micro- and meso-structured chalcogenides and their ion exchange properties

    Science.gov (United States)

    Ding, Nan

    2007-12-01

    are aligned through each layer, adding a pseudo-3D feature to the compounds. This leads to excellent ion-exchange properties. More remarkably, these compounds showed exceptional selectivity for Cs+ ions than any other alkali metal and alkaline earth metal cations due to the soft acid (Cs +)/soft base (S2-) attraction and the size discrimination imposed by the open windows within the frameworks. These properties point to a new direction of designing compounds for possible radioactive 137Cs+ remediation. With the even larger surfactant molecules in water, metal cations In 3+, Zn2+ and Cd2+ can connect [SbSe 4]3- clusters via coordination chemistry to form cubic and hexagonal mesophases. In addition to the linking effect, these metal cations also played the role of Lewis acids and partially reduced [SbSe4] 3- to [SbSe3]3-, both of which are present in the long-range ordered mesostructures. Short range order in a mesostuctured chalcogenide was approached, when structurally rigid Chevrel clusters [Re 6Se6Br8]2- were linked by triselenide anions via metathesis. Higher angle Bragg reflections of this compound provided an opportunity to build a structural model for the first time for a chalcogen-based mesophase.

  11. Separation of zirconium from hafnium by ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Felipe, Elaine C.B.; Palhares, Hugo G.; Ladeira, Ana Claudia Q., E-mail: elainecfelipe@yahoo.com.br, E-mail: hugopalhares@gmail.com, E-mail: ana.ladeira@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    Zirconium and hafnium are two of the most important metals for the nuclear industry. Hafnium occurs in all zirconium ores usually in the range 2 - 3%. However, for the most nuclear industry applications, it is necessary to use a zirconium of extremely pure level. The current work consists in the separation of zirconium and hafnium by the ion exchange method in order to obtain a zirconium concentrate of high purity. The zirconium and hafnium liquors were produced from the leaching of the Zr(OH){sub 4} and Hf(OH){sub 4} with nitric acid for 24 hours. From these two liquors it was prepared one solution containing 7.5 x 10{sup -2} mol L{sup -1} of Zr and 5.8 x 10{sup -3} mol L{sup -1} of Hf with acidity of 1 M. Ion exchange experiments were carried out in batch with the resins Dowex 50WX4, Dowex 50WX8 100, Dowex 50WX8 50, Amberlite IR-120 and Marathon C at constant temperature 28 deg C. Other variables such as, acidity and agitation were kept constant. The data were adjusted to Langmuir equation in order to calculate the maximum loading capacity (q{sub max}) of the resins, the distribution coefficient (K{sub d}) for Zr and Hf and the separation factor (α{sub Hf}{sup Zr} ). The results of maximum loading capacity (q{sub max}) for Zr and Hf, in mmol g{sup -}1, showed that the most suitable resins for columns experiments are: Dowex 50WX4 50 (q{sub max} Z{sub r} = 2.21, Hf = 0.18), Dowex 50WX8 50 (q{sub max} Zr = 1.89, Hf = 0.13) and Amberlite (q{sub max} Zr = 1.64, Hf = 0.12). However, separations factors, α{sub Hf}{sup Zr}, showed that the resins are not selective. (author)

  12. Ion exchange and dehydration experimental studies of clinoptilolite: Implications to zeolite dating

    International Nuclear Information System (INIS)

    WoldeGabriel, G.

    1995-02-01

    Variable effects were noted on the argon (Ar) and potassium (K) contents of clinoptilolite fractions used in ion-exchange and dehydration experiments. The K contents of clinoptilolite fractions were differently affected during cation exchange with Ca-, Cs-, K-, and Na-chloride solutions. Ar was generally less affected during these experiments, except for a Na-clinoptitolite fraction exchanged for five days. Loss of Ar during organic heavy-liquid treatment and cleaning using acetone and deionized water does occur, as indicated by comparing the amounts of radiogenic Ar of treated and untreated fractions. Moreover, a regular decrease in radiogenic Ar contents was noted in clinoptilolite fractions during dehydration experiments at different temperatures for 16 hours. Comparable losses do not occur from saturated samples that were heated in 100 C for more than five months. Water appears to play a vital role in stabilizing the clinoptilolite framework structure and in the retention of Ar. The radiogenic Ar depletion pattern noted in clinoptilolite fractions dehydrated in unsaturated environment at different temperatures is similar to variations in the amount of radiogenic Ar observed in clinoptilolite samples from the unsaturated zone of an altered tuff. These results can be used to evaluate the extent of zeolitic water (and hence Ar) retention in unsaturated geologic settings. The utility of alkali zeolites (e.g., phillipsite, clinoptilolite, and mordenite) from low-temperature, open-hydrologic alteration as potential dateable minerals was evaluated using the K/Ar method as part of the Yucca Mountain Site Characterization Project, which is evaluating Yucca Mountain, Nevada, as a potential high-level radioactive waste repository site

  13. Sorptive Removal of Cesium and Cobalt Ions in a Fixed bed Column Using Lewatit S100 Cation Exchange Resin

    International Nuclear Information System (INIS)

    El-Naggar, M.R.; Ibrahim, H.A.; El-Kamash, A.M.

    2014-01-01

    The sorptive removal of cesium and cobalt ions from aqueous solutions in a fixed bed column packed with Lewatit S100® cation exchange resin has been investigated. A preliminary batch studies were performed to estimate the effect of pH and contact time on the sorption process. Results indicated that Cs + and Co 2+ could be efficiently removed using Lewatit S100® at a ph range of 4-7 with more affinity towards Cs than Co 2+ . Kinetic models have been applied to the sorption rate data and the relevant parameters were determined. The obtained results indicated that the sorption of both Cs + and Co 2+ on Lewatit S100 followed pseudo second-order rather than pseudo first-order or Morris-Webber model. Fixed bed experiments were conducted at a constant initial concentration of 100 mg/l whereas the effect of bed depth (3, 4.5 and 6 cm) and volumetric flow rate (3 and 5 ml/min.) on the breakthrough characteristics of the fixed bed sorption systems were determined. The experimental sorption data were fitted to the well-established column models namely; Thomas and BDST models to compute the different model parameters. The higher column sorption capacities were obtained at bed depth of 3 cm with a flow rate of 3 ml/min., for both Cs + and Co 2+ . The BDST model appeared to describe experimental results better than Thomas model. Results indicate that Lewatit S100® is an efficient material for the removal of cesium and cobalt ions from aqueous solutions.

  14. Study of plasma off-gas treatment from spent ion exchange resin pyrolysis.

    Science.gov (United States)

    Castro, Hernán Ariel; Luca, Vittorio; Bianchi, Hugo Luis

    2017-03-23

    Polystyrene divinylbenzene-based ion exchange resins are employed extensively within nuclear power plants (NPPs) and research reactors for purification and chemical control of the cooling water system. To maintain the highest possible water quality, the resins are regularly replaced as they become contaminated with a range of isotopes derived from compromised fuel elements as well as corrosion and activation products including 14 C, 60 Co, 90 Sr, 129 I, and 137 Cs. Such spent resins constitute a major proportion (in volume terms) of the solid radioactive waste generated by the nuclear industry. Several treatment and conditioning techniques have been developed with a view toward reducing the spent resin volume and generating a stable waste product suitable for long-term storage and disposal. Between them, pyrolysis emerges as an attractive option. Previous work of our group suggests that the pyrolysis treatment of the resins at low temperatures between 300 and 350 °C resulted in a stable waste product with a significant volume reduction (>50%) and characteristics suitable for long-term storage and/or disposal. However, another important issue to take into account is the complexity of the off-gas generated during the process and the different technical alternatives for its conditioning. Ongoing work addresses the characterization of the ion exchange resin treatment's off-gas. Additionally, the application of plasma technology for the treatment of the off-gas current was studied as an alternative to more conventional processes utilizing oil- or gas-fired post-combustion chambers operating at temperatures in excess of 1000 °C. A laboratory-scale flow reactor, using inductively coupled plasma, operating under sub-atmospheric conditions was developed. Fundamental experiments using model compounds have been performed, demonstrating a high destruction and removal ratio (>99.99%) for different reaction media, at low reactor temperatures and moderate power consumption

  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. Cs2.5H0.5PWO40/SiO2 as addition self-humidifying composite membrane for proton exchange membrane fuel cells

    International Nuclear Information System (INIS)

    Wang, L.; Yi, B.L.; Zhang, H.M.; Xing, D.M.

    2007-01-01

    In this paper, we first reported a novel self-humidifying composite membrane for the proton exchange membrane fuel cell (PEMFC). Cs 2.5 H 0.5 PWO 40 /SiO 2 catalyst particles were dispersed uniformly into the Nafion (registered) resin, and then Cs 2.5 H 0.5 PWO 40 -SiO 2 /Nafion composite membrane was prepared using solution-cast method. Compared with the H 3 PWO 40 (PTA) , the Cs 2.5 H 0.5 PWO 40 /SiO 2 was steady due to the substitute of H + with Cs + and the interaction between the Cs 2.5 H 0.5 PWO 40 and SiO 2 . And compared with the performance of the fuel cell with commercial Nafion (registered) NRE-212 membrane, the cell performance with the self-humidifying composite membrane was obviously improved under both humidified and dry conditions at 60 and 80 o C. The best performance under dry condition was obtained at 60 o C. The self-humidifying composite membrane could minimize membrane conductivity loss under dry conditions due to the presence of catalyst and hydrophilic Cs 2.5 H 0.5 PWO 40 /SiO 2 particles

  17. Use of water as displacing agent in ion exchange chromatographic separation of isotope of boron using weak base ion exchange resin

    International Nuclear Information System (INIS)

    Sharma, B.K.; Mohanakrishnan, G.; Anand Babu, C.; Krishna Prabhu, R.

    2008-01-01

    Experiments were undertaken to study the feasibility of using weakly basic anion exchange resin for enrichment of isotopes of boron by ion exchange chromatography and water as eluent. The results of experiments carried out to determine total chloride capacity (TCC), strong base capacity (SBC) of the resin at different concentrations of boric acid and enrichment profiles are reported in this paper. (author)

  18. Ion exchange separation of nitrate from uranium compounds and its determination by spectrophotometry and ion chromatography

    International Nuclear Information System (INIS)

    Pires, M.A.F.; Atalla, L.T.; Abrao, A.

    1985-11-01

    A procedure for the separation of nitrate from uranium compounds by retaintion of uranyl ion on a cationic ion exchanger and its determination in the effluent is described. Nitrate is analysed by the spectrometric method with 1-phenol-2,4-dissulphonic acid. This determination covers the 1 to 10 μg NO - 3 /mL range and requires an amount of 10 to 100 μg NO - 3 . The main interference is uranium (VI) due its own intense yellow color. This difficulty is overcome by the complete separation of UO 2 ++ with the cationic resin. Alternatively, the ion chromatography technique is used for the determination of nitrate in the effluent of the cationic resin. The determination was easily made by the comparison of the nitrate peak hights of the analyte and the standard solutions. The ion chromatography method is very sensitive (0,3 μg NO - 3 /mL), reproducible and suitable for routine analysis and permits the determination of fraction of part per million of nitrate in uranium. The results of nitrate determination using both spectrophotometric and ion chromatography techniques are compared. The method is being routinely applied for the quality control of uranium compounds in the fuel cycle, specially uranium oxide, ammonium diuranate, uranium peroxide and ammonium uranyl tricarbonate. (Author) [pt

  19. Isotopic exchange rate of cobalt ions between hydrous tin(IV) oxide and aqueous solutions

    International Nuclear Information System (INIS)

    Inoue, Yasushi; Yamazaki, Hiromichi; Itami, Akira

    1989-01-01

    The isotopic exchange rate of cobalt ions between hydrous tin(IV) oxide ion exchanger and aqueous solutions was radiochemically measured to obtain fundamental data which are useful for elucidating the ion-exchange kinetics of the material for the transition metal elements. The rate can be understood by considering that the cobalt ions were present in the exchanger as three kinds of species: (A 1 ) Free ions which can diffuse in the exchanger particles, (A 2 ) Weakly bound ions to the exchange sites which exchange rapidly with A 1 , and (B) Covalently fixed ions to the exchange sites which exchange very slowly with A 1 . At low fraction of B, the rate is controlled by the diffusion of A 1 with the effective diffusion coefficient, D eff , the values of which depend on the concentration ratios of A 2 to A 1 . When B predominates over the A species, the concentration ratios of B to A 1 affect greatly D eff . The values of D eff and their activation energy(20 kJ/mol) were also estimated

  20. Development of a multi-functional reprocessing process based on ion-exchange method by using tertiary pyridine-type resin

    International Nuclear Information System (INIS)

    Koyama, Shin-ichi; Ozawa, Masaki; Suzuki, Tatsuya; Fujii, Yasuhiko

    2006-01-01

    A series of separation experiment was performed in order to study a multi-functional spent fuel reprocessing process based on ion-exchange technique. The tertiary pyridine-type anion-exchange resin was used in this experiment and the mixed oxide fuel highly irradiated in the experimental fast reactor ''JOYO'' was used as a reference spent fuel. As the result, 106 Ru + 125 Sb, 137 Cs + 155 Eu + 144 Ce, plutonium, americium and curium could be separated from the irradiated fuel by only three steps of ion-exchange. The decontamination factor of 137 Cs and trivalent lanthanides ( 155 Eu, 144 Ce) in the final americium product exceeded 3.9 x 10 4 and 1.0 x 10 5 , respectively. The decontamination factor for the mutual separation of 243 Cm and 241 Am was larger than 2.2 x 10 3 for the americium product and, moreover, the content of 137 Cs, trivalent lanthanides and 243 Cm included in 241 Am product did not exceed 2 ppm. These results prove that the proposed simplified separation process has a reality as a candidate for future reprocessing process based on the partitioning and transmutation concept. (author)

  1. An isotopic method to distinguish between ion exchange and adsorption of diazonium cations of zeolites

    International Nuclear Information System (INIS)

    Mohl, M.; Fejes, P.; Horvath, G.

    1984-01-01

    The ion exchange isotherms of two different diazonium cations have been determined on synthetic mordenite and faujasite using 22 Na as radiotracer. Under similar conditions (but with no radiotracer) the isotherms were followed spectrophotometrically so that a comparison between the amounts of ion exchanged and adsorbed cations can be made. (author)

  2. Group IV nanocrystals with ion-exchangeable surface ligands and methods of making the same

    Science.gov (United States)

    Wheeler, Lance M.; Nichols, Asa W.; Chernomordik, Boris D.; Anderson, Nicholas C.; Beard, Matthew C.; Neale, Nathan R.

    2018-01-09

    Methods are described that include reacting a starting nanocrystal that includes a starting nanocrystal core and a covalently bound surface species to create an ion-exchangeable (IE) nanocrystal that includes a surface charge and a first ion-exchangeable (IE) surface ligand ionically bound to the surface charge, where the starting nanocrystal core includes a group IV element.

  3. High-capacity, selective solid sequestrants for innovative chemical separation: Inorganic ion exchange approach

    International Nuclear Information System (INIS)

    Bray, L.

    1995-01-01

    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

  4. Isolation of nitrosylruthenium nitrato complexes by ion exchange and extraction chromatography

    International Nuclear Information System (INIS)

    Huang, H.; Liu, L.

    TBP Levextrel and cation exchange resins were used to separate RuNO nitrato complexes of different nitric acid concentrations. 7402 quaternary ammonium salt Levextrel was used instead of an anionic exchange resin to separate anionic and neutral complex ions. The results indicated that D 3 and D 4 , which can easily be extracted by TBP, were anionic and neutral complex ions

  5. A method for embedding granulated or spent ion-exchanging organic substances in concrete

    International Nuclear Information System (INIS)

    Christensen, H.; Jejes, P.

    1976-01-01

    A method of embedding in concrete a spent ion-exchanging organic substance originating from a scrubbing-circuit of a nuclear reactor Prior to solidification of the mixture, a substance is incorporated therewith said substance being capable of preventing water in the grains of the ion-exchanging substance from penetrating into the solidified product

  6. Nanomaterials-Enhanced Electrically Switched Ion Exchange Process for Water Treatment

    International Nuclear Information System (INIS)

    Lin, Yuehe; Choi, Daiwon; Wang, Jun; Bontha, Jagannadha R.

    2009-01-01

    The objective of our work is to develop an electrically switched ion exchange (ESIX) system based on conducting polymer/carbon nanotube (CNT) nanocomposites as a new and cost-effective approach for removal of radioactive cesium, chromate, and perchlorate from contaminated groundwater. The ESIX technology combines ion exchange and electrochemistry to provide a selective, reversible method for the removal of target species from wastewater. In this technique, an electroactive ion exchange layer is deposited on a conducting substrate, and ion uptake and elution are controlled directly by modulation of the potential of the layer. ESIX offers the advantages of highly-efficient use of electrical energy combined with no secondary waste generation. Recently, we have improved upon the ESIX process by modifying the conducting substrate with carbon nanotubes prior to the deposition of the electroactive ion exchanger. The nanomaterial-based electroactive ion exchange technology will remove cesium-137, chromate, and perchlorate rapidly from wastewater. The high porosity and high surface area of the electroactive ion exchange nanocomposites results in high loading capacity and minimize interferences for non-target species. Since the ion adsorption/desorption is controlled electrically without generating a secondary waste, this electrically active ion exchange process is a green process technology that will greatly reduce operating costs

  7. Proceedings of the 5. Symposium on ion exchange held at the Lake Balaton, Hungary, 28-31 May 1986

    International Nuclear Information System (INIS)

    Hajos, P.; Marton, A.

    1986-01-01

    Major trends of ion exchange researches and applications were discussed at the 5th international conference on ion echange held at Lake Balaton, Balatonfuered, Hungary. The 5 plenary lectures and the 98 papers delivered in 4 sessions dealt with theoretical aspects of ion exchange, different types of ion exchange materials including organic and inorganic ones, analytical applications of ion exchange processes, e.g. ion chromatography, HPLC and special technological procedures. Several examples were presented for ion exchange separations of nuclear interest such as the decontamination of radioactive wastes, the radiochemical analysis of the primary coolant, uranium recovery, the application of selective inorganic sorbents. (V.N.)

  8. Complex ion kinetics. Reaction rates on ion-exchange resins compared to those in water

    International Nuclear Information System (INIS)

    Liss, I.B.; Murmann, R.K.

    1975-01-01

    A comparison has been made between the rates in water and on an ion-exchange resin for the aquation of [(NH 3 ) 5 CoOReO 3 ] 2+ and [(H 2 O) 5 CrCl] 2+ and for the 18 O isotopic exchange of water with [(NH 3 ) 5 Co(OH 2 )] 3+ and ReO 4 - . The rate of water exchange on [(NH 3 ) 5 Co(OH 2 )] 3+ was not changed by association with Dowex 50W resins. Aquation of [(NH 3 ) 5 CoOReO 3 ] 2+ and water exchange on ReO 4 - had modified pH dependencies when associated with a resin. With the cobalt complex the rates were faster on the resin in the acidic region and slower on the resin in the basic region. A new term in the rate equation was observed when ReO 4 - was on the resin, first order in H + , while the other terms appear to be unchanged. Aquation of [(H 2 O) 5 CrCl] 2+ was much slower when it was absorbed on the resin. This was related to the known ionic strength effect of the reaction. (auth)

  9. Ion mobility spectrometry-hydrogen deuterium exchange mass spectrometry of anions: part 1. Peptides to proteins.

    Science.gov (United States)

    Donohoe, Gregory C; Khakinejad, Mahdiar; Valentine, Stephen J

    2015-04-01

    Ion mobility spectrometry (IMS) coupled with hydrogen deuterium exchange (HDX)-mass spectrometry (MS) has been used to study the conformations of negatively-charged peptide and protein ions. Results are presented for ion conformers of angiotensin 1, a synthetic peptide (SP), bovine insulin, ubiquitin, and equine cytochrome c. In general, the SP ion conformers demonstrate a greater level of HDX efficiency as a greater proportion of the sites undergo HDX. Additionally, these ions exhibit the fastest rates of exchange. Comparatively, the angiotensin 1 ions exhibit a lower rate of exchange and HDX level presumably because of decreased accessibility of exchange sites by charge sites. The latter are likely confined to the peptide termini. Insulin ions show dramatically reduced HDX levels and exchange rates, which can be attributed to decreased conformational flexibility resulting from the disulfide bonds. For the larger ubiquitin and protein ions, increased HDX is observed for larger ions of higher charge state. For ubiquitin, a conformational transition from compact to more elongated species (from lower to higher charge states) is reflected by an increase in HDX levels. These results can be explained by a combination of interior site protection by compact conformers as well as decreased access by charge sites. The elongated cytochrome c ions provide the largest HDX levels where higher values correlate with charge state. These results are consistent with increased exchange site accessibility by additional charge sites. The data from these enhanced IMS-HDX experiments are described in terms of charge site location, conformer rigidity, and interior site protection.

  10. Transition from the constant ion mobility regime to the ion-atom charge-exchange regime for bounded collisional plasmas

    International Nuclear Information System (INIS)

    Poggie, Jonathan; Sternberg, Natalia

    2005-01-01

    A numerical and analytical study of a planar, collisional, direct-current, plasma-wall problem is presented. The fluid model for the problem is first validated by comparing numerical solutions with experimental data for low-pressure (∼0.1 Pa) electrode sheaths with wall potentials on the order of -100 V. For electric potential, ion number density, and ion velocity, good agreement was found between theory and experiment from within the sheath out to the bulk plasma. The frictional drag resulting from ion-neutral collisions is described by a model incorporating both linear and quadratic velocity terms. In order to study the transition from the constant ion mobility regime (linear friction) to the ion-atom charge-exchange collision regime (quadratic friction), the theoretical model was examined numerically for a range of ion temperatures and ion-neutral collision rates. It was found that the solution profiles in the quasineutral plasma depend on the ion temperature. For low ion temperatures they are governed mainly by the ion-atom charge-exchange regime, whereas for high temperatures they are governed by the constant ion mobility regime. Quasineutral plasma models corresponding to these two limiting cases were solved analytically. In particular, an analytical plasma solution is given for the ion-atom charge exchange regime that includes the effects of ion inertia. In contrast to the quasineutral plasma, the sheath is always governed for low to moderate collision rates by the ion-atom charge-exchange regime, independent of the ion temperature. Varying the collision rate, it was shown that when the wall potential is sufficiently high, the sheath cannot be considered collisionless, even if the collision rate is quite small

  11. chemical studies and sorption behavior of some hazardous metal ions on polyacrylamide stannic (IV) molybdophosphate as 'organic - inorganic' composite cation - exchanger

    International Nuclear Information System (INIS)

    Abdel-Galil, E.A.M.

    2010-01-01

    compsite materials formed by the combination of multivalent metal acid salts and organic polymers provide a new class of (organic-inorganic) hypride ion exchangers with better mechanical and granulometric properties, good ion-exchange capacity, higher chemical and radiation stabilites, reproducibility and selectivity for heavy metals. this material was characterized using X-ray (XRD and XRF), IR, TGA-DTA and total elemental analysis studies. on the basis of distribution studies, the material has been found to be highly selective for pb(II). thermodynamic parameters (i.e δG 0 , δ S 0 and δH 0 ) have also been calculated for the adsorption of Pb 2+ , Cs + , Fe 3+ , Cd 2+ , Cu +2 , Zn 2+ , Co 2+ and Eu 3+ ions on polyacrylamide Sn(IV) molybdophosphate showing that the overall adsorption process is spontaneous endothermic. the mechanism of diffusion of Fe 3+ , Co 2+ , Cu +2 , Zn 2+ , Cd 2+ , Cs + , Pb 2+ and Eu 3+ in the H-form of polyacrylamide Sn(IV) molybdophosphate composite as cation exchanger was studied as a function of particle size, concentration of the exchanging ions, reaction temperature, dring temperature and pH. the exchange rate was controlled by particle diffusion mechanism as a limited batch techneque and is confirmed from straight lines of B versus 1/r 2 polts. the values of diffusion coefficients, activation energy and entropy of activation were calculated and their significance was discussed. the data obtained have been comared with that reported for other organic and inorganic exchangers.

  12. Praseodymium ion doped phosphate glasses for integrated broadband ion-exchanged waveguide amplifier

    Energy Technology Data Exchange (ETDEWEB)

    Shen, L.F. [School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034 (China); Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong (China); Chen, B.J. [Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong (China); Lin, H., E-mail: lhai8686@yahoo.com [School of Textile and Material Engineering, Dalian Polytechnic University, Dalian 116034 (China); Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong (China); Pun, E.Y.B. [Department of Electronic Engineering, City University of Hong Kong, Kowloon, Hong Kong (China)

    2015-02-15

    Highlights: • Effective near-infrared emission (1380-1525 nm) is observed in Pr{sup 3+}-doped phosphate glasses. • Effective bandwidth of {sup 1}D{sub 2} → {sup 1}G{sub 4} transition emission is obtained to be 124 nm. • Channel waveguides have been fabricated by K{sup +}-Na{sup +} ion-exchange method. • Pr{sup 3+}-doped phosphate glasses are promising in developing integrated broadband waveguide amplifier. - Abstract: Effective near-infrared emission covering the fifth optical telecommunication window (1380-1525 nm) has been observed in Pr{sup 3+}-doped phosphate (NMAP) glasses. Judd-Ofelt parameters Ω{sub 2} (6.38 × 10{sup −20} cm{sup 2}), Ω{sub 4} (20.30 × 10{sup −20} cm{sup 2}) and Ω{sub 6} (0.40 × 10{sup −20} cm{sup 2}) indicate a high inversion asymmetrical and strong covalent environment in the optical glasses. The effective bandwidth (Δλ{sub eff}) of the corresponding {sup 1}D{sub 2} → {sup 1}G{sub 4} transition emission is obtained to be 124 nm, and the maximum stimulated emission cross-section (σ{sub em-max}) at 1468 nm is derived to be 1.14 × 10{sup −20} cm{sup 2}. Channel waveguide was fabricated successfully by K{sup +}-Na{sup +} ion-exchange method with mode field diameter of 8.8 μm in the horizontal direction and 6.7 μm in the vertical direction. Broad effective bandwidth, large emission cross-section and perfect thermal ion-exchangeability indicate that Pr{sup 3+}-doped NMAP phosphate glasses are promising in developing integrated broadband waveguide amplifier, especially operating at E- and S-bands which belong to the fifth optical telecommunication window.

  13. Exchange of Th, U and Pu on macroporous ion exchange resins

    International Nuclear Information System (INIS)

    Nadkarni, M.N.; Mayankutty, P.C.; Pillai, N.S.; Shinde, S.S.

    1977-01-01

    Absorption of Th, U and Pu on macroporous ion exchangers, Amberlyst 15 (cationic) and Amberlyst A-26 (anionic) were studied in nitric acid solutions and the results were found comparable with those on their microreticular counter parts, Dowex 50x8 and Dowex IX4. With a view to evalute the efficiency of Amberlyst A-26 for the final purification of plutonium from the purex process stream, detailed studies conducted to determine the breakthrough capacity of Pu(IV) from 7.2 M nitric acid, elution by 0.5 M nitric acid and the decontamination factors for uranium and zirconium-95. Because of its faster kinetics, Amberlyst A-26 exhibited a much more efficient elution of Pu(IV) by 0.5 M nitric acid than Dowex IX4. (author)

  14. Revised Thermal Analysis of LANL Ion Exchange Column

    Energy Technology Data Exchange (ETDEWEB)

    Laurinat, J

    2006-04-11

    This document updates a previous calculation of the temperature distributions in a Los Alamos National Laboratory (LANL) ion exchange column.1 LANL operates two laboratory-scale anion exchange columns, in series, to extract Pu-238 from nitric acid solutions. The Defense Nuclear Facilities Safety Board has requested an updated analysis to calculate maximum temperatures for higher resin loading capacities obtained with a new formulation of the Reillex HPQ anion exchange resin. The increased resin loading capacity will not exceed 118 g plutonium per L of resin bed. Calculations were requested for normal operation of the resin bed at the minimum allowable solution feed rate of 30 mL/min and after an interruption of flow at the end of the feed stage, when one of the columns is fully loaded. The object of the analysis is to demonstrate that the decay heat from the Pu-238 will not cause resin bed temperatures to increase to a level where the resin significantly degrades. At low temperatures, resin bed temperatures increase primarily due to decay heat. At {approx}70 C a Low Temperature Exotherm (LTE) resulting from the reaction between 8-12 M HNO{sub 3} and the resin has been observed. The LTE has been attributed to an irreversible oxidation of pendant ethyl benzene groups at the termini of the resin polymer chains by nitric acid. The ethyl benzene groups are converted to benzoic acid moities. The resin can be treated to permanently remove the LTE by heating a resin suspension in 8M HNO{sub 3} for 30-45 minutes. No degradation of the resin performance is observed after the LTE removal treatment. In fact, heating the resin in boiling ({approx}115-120 C) 12 M HNO{sub 3} for 3 hr displays thermal stability analogous to resin that has been treated to remove the LTE. The analysis is based on a previous study of the SRS Frames Waste Recovery (FWR) column, performed in support of the Pu-238 production campaign for NASA's Cassini mission. In that study, temperature transients

  15. Influence of ion bombardment induced patterning of exchange bias in pinned artificial ferrimagnets on the interlayer exchange coupling

    Energy Technology Data Exchange (ETDEWEB)

    Schmalhorst, Jan; Reiss, Guenter; Hoenik, V. [Thin Films and Nanostructures, Department of Physics, Univ. Bielefeld (Germany); Weis, Tanja; Engel, Dieter; Ehresmann, Arno [Institute of Physics and Center for Interdisciplinary Nanostructure Science and Technology, Kassel Univ. (Germany)

    2007-07-01

    Artificial ferrimagnets (AFi) have many applications as, e.g., pinned reference electrodes in magnetic tunnel junctions. It is known that the application of ion bombardment induced magnetic patterning with He ions on a single layer reference electrode of magnetic tunnel junctions is possible. For some applications a combination of ion bombardment induced magnetic patterning and artificial ferrimagnets as a reference electrode is desirable. The effect of ion bombardment induced magnetic patterning on pinned artificial ferrimagnets with a Ru interlayer which is frequently used in magnetic tunnel junctions as well as pinned AFis with a Cu interlayer has been tested. Special attention has been given to the question whether the antiferromagnetic interlayer exchange coupling can withstand the ion dose necessary to turn the exchange bias.

  16. Ion exchange equilibrium for some uni-univalent and uni-divalent ...

    African Journals Online (AJOL)

    The study on thermodynamics of ion exchange equilibrium for uni-univalent Cl-/I-, Cl-/Br-, and uni-divalent Cl-/SO42-, Cl-/C2O42- reaction systems was carried out using ion exchange resin Duolite A-102 D. The equilibrium constant K was calculated by taking into account the activity coefficient of ions both in solution as well ...

  17. Coupled acoustic-gravity field for dynamic evaluation of ion exchange with a single resin bead.

    Science.gov (United States)

    Kanazaki, Takahiro; Hirawa, Shungo; Harada, Makoto; Okada, Tetsuo

    2010-06-01

    A coupled acoustic-gravity field is efficient for entrapping a particle at the position determined by its acoustic properties rather than its size. This field has been applied to the dynamic observation of ion-exchange reactions occurring in a single resin bead. The replacement of counterions in an ion-exchange resin induces changes in its acoustic properties, such as density and compressibility. Therefore, we can visually trace the advancement of an ion-exchange reaction as a time change in the levitation position of a resin bead entrapped in the field. Cation-exchange reactions occurring in resin beads with diameters of 40-120 microm are typically completed within 100-200 s. Ion-exchange equilibrium or kinetics is often evaluated with off-line chemical analyses, which require a batch amount of ion exchangers. Measurements with a single resin particle allow us to evaluate ion-exchange dynamics and kinetics of ions including those that are difficult to measure by usual off-line analyses. The diffusion properties of ions in resins have been successfully evaluated from the time change in the levitation positions of resin beads.

  18. Ion-exchange equilibrium of Fe3+-Cl- and UO22+-Cl- systems in a porous anion exchanger

    International Nuclear Information System (INIS)

    Takeda, Kunihiko; Kawakami, Fumiaki; Sasaki, Mitsunaga

    1985-01-01

    The ion-exchange equilibrium behavior of complex ions was investigatided in the systems of UO 2 2+ - Cl - and Fe 3+ - Cl - using an anion exchanger. It was performed by examining the dependency of adsorption distribution and selectivity of complexes on the micro structure of ion-exchangers, and temperature-dependency of selectivity. Changes in micropore structure of the ion-exchanger were found to have a significant effect on selectivity; the coefficient of selectivity and the average valence of the adsorbed species increased as the discrete pore ratio used as the index for pore structure decreased. In this study, equilibrium reactions were regarded as a sort of addition reaction for a easier analysis. This analysis based on the concept of addition chemical potential suggested that decreases in the discrete pore ratio were advantageous for the adsorption of complex ion species with higher valence, and average valence of the adsorbed species within the exchanger was shifted to the higher side. For this reason, it is assumed that the coefficient of selectivity became larger with a decrease in the discrete pore ratio. There is also a marked change in the coefficient of selectivity with temperature, and this becomes greater the higher the temperature. The ΔH of the present system accompanying the complex forming reaction is estimated to be 7 to 8 kcal/mol, and this value suggests that the temperature effect of the complex forming reaction contributes greatly to the change in selectivity with temperature. (author)

  19. Accelerated electron exchange between U4+ and UO22+ by foreign metal ions

    International Nuclear Information System (INIS)

    Obanawa, Heiichiro; Onitsuka, Hatsuki; Takeda, Kunihiko

    1990-01-01

    The rate constant of U 4+ -UO 2 2+ electron exchange (k et ) was increased by more than 100 times in the presence of various metal ions. The larger rate constant was observed for the smaller difference of the standard reduction potential strength between metal ion and UO 2 2+ ion (Δμ θ e ). Detailed investigation of the electron exchange reaction in the presence of Mo 5+ suggested that the mechanism of the electron transfer reaction catalyzed by metal ions is the outer-sphere type independent of U-Clcomplex ions. (author)

  20. Work function dependence and isotope effect in the production of negative hydrogen ions during sputtering of adsorbed hydrogen on Cs covered Mo(100) surfaces

    International Nuclear Information System (INIS)

    Yu, M.L.

    1977-01-01

    The enhancement of the H - yield, during sputtering of adsorbed hydrogen on a Mo(100) surface, by a Cs overlayer was investigated. An exponential dependence of the H - yield on the work function was observed for a wide range of Cs coverages. A simple electron tunneling model was proposed. A large reduction in the ion yield was also observed when D 2 replaced H 2 as the adsorbate

  1. Recovery of gold with ion exchange resin from leaching solution by acidothioureation. Ion kokan jushiho ni yoru ryusan sansei chio nyoso kinshinshutsueki kara no kin no kaishu ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Nakahiro, Y.; Ninae, M.; Kusaka, E.; Wakamatsu, T. (Kyoto University, Kyoto (Japan). Faculty of Engineering); Horio, Y. (Yamaha Co. Ltd., Tokyo (Japan))

    1991-12-25

    Recovery of gold with ion exchange resin from leaching solution by acidothioureation, and elution of gold from ion exchange resin with gold were studied experimentally. As the result of batch adsorption experiments of Au(TU){sub 2}{sup +} into various kinds of ion exchange resins, strong acidic cation exchange resin was most suitable, and gold was fully adsorbed into such resin in the pH range from 1.2 to 2.0 without any effects of thiourea in the leaching solution on adsorption of gold. As the result of batch elution experiments in various kinds of eluates, copper was eluted in HNO{sub 3}(1 N) + H{sub 2}O{sub 2}(1wt%) elute, both iron and zinc in NH{sub 4}NO{sub 3}(0.5 M) elute, and gold in Na{sub 2}S{sub 2} O{sub 3}(0.05 M) elute resulting in the recovery of gold. As the result of column elution experiments, Amberlite 200C was most effective among some ion exchangers used for recovery of Au(CS(NH{sub 2}){sub 2}){sub 2}{sup +}. 16 refs., 15 figs.

  2. Pilot plant of continuous ion-exchange in fluidized bed

    International Nuclear Information System (INIS)

    Botella, T.; Otero de Becerra, J.; Gasos, P.

    1985-01-01

    Research and development on continuous ion-exchange processes has been a major item in hydrometallurgy. This new technology has been under development during the last 15 years in the leading countries at uranium hydrometallurgy. The fluidized bed multi-stage column technique is proven to be the most attractive one, and since 1977 several commercial plants have begun production, some of them with a throughput of 500 cubic meters of pregnant liquour per hour. J.E.N. undertook the study of this new technology for uranium recovery in the early 70's. In 1979 a pilot plant had been installed, based on previous laboratory and smaller pilot plant experience. The plant was designed following JEN's own technology and has been operating successfully at a flow rate of near 0.5 cubic meters per hour. The test runs and the main processing, engineering and operation features are described. At present a demonstation plant is under design, and this installation will provide the necessary know-how for the construction and operation of a commercial scale plant. (author)

  3. Electrochemical ion-exchange for active liquid waste treatment

    International Nuclear Information System (INIS)

    Turner, A.D.; Bridger, N.J.; Jones, C.P.

    1992-10-01

    Electrochemical ion exchange (EIX) has been firmly established as an effective process for the treatment of a wide range of liquid radioactive wastes. Both organic (for low specific activity streams) and inorganic systems (for higher activity wastes) have been demonstrated. A low cost current feeder electrode has also been developed, with a projected lifetime of > 6 years. While cation EIX can be used for the treatment of low salt content streams, combination with anion EIX to control the pH can extend its range of application. At the same time, it is also able to remove activity complexed in an anionic form. AEIX has also demonstrated its ability to remove radionuclides with insoluble hydroxides (eg Co, U and Pu) from both high and low salt content streams. EIX has been successfully scaled-up form the bench-top scale by increasing electrode size by a factor of 11, and then by operating five units in parallel. An improvement in performance of by a factor 3 was observed over a simple increase in area, due to the minimization of edge effects in the larger units. The most significant advantage of EIX is its compactness -with plant sizes of 1000). (Author)

  4. Ion Exchange Resin and Clay Vitrification by Plasma Discharges

    International Nuclear Information System (INIS)

    Diaz A, Laura V.; Pacheco S, Joel O.; Pacheco P, Marquidia; Monroy G, Fabiola; Emeterio H, Miguel; Ramos F, Fidel

    2006-01-01

    The lack of treatment of a low and intermediate level radioactive waste (LILRW) lead us to propose a vitrification process based on a plasma discharge; this technique incorporates LILRW into a matrix glass composed of ceramic clays material. The Mexican Institute of Nuclear Research (ININ), uses an ion exchange resin IRN 150 (styrene-divinilbence copolymer) in the TRIGA MARK III nuclear reactor. The principal objective of this resin is to absorb particles containing heavy metals and low-level radioactive particles. Once the IRN 150 resin filter capacity has been exceeded, it should be replaced and treated as LILRW. In this work, a transferred plasma system was realized to vitrify this resin taking advantage of its high power density, enthalpy and chemical reactivity as well as its rapid quenching and high operation temperatures. In order to characterize the morphological structure of these clay samples, Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Thermogravimetric analysis (TGA) techniques were applied before and after the plasma treatment

  5. Application of ion exchange resin in floating drug delivery system.

    Science.gov (United States)

    Upadhye, Abhijeet A; Ambike, Anshuman A; Mahadik, Kakasaheb R; Paradkar, Anant

    2008-10-01

    The purpose of this study was to explore the application of low-density ion exchange resin (IER) Tulsion(R) 344, for floating drug delivery system (FDDS), and study the effect of its particle size on rate of complexation, water uptake, drug release, and in situ complex formation. Batch method was used for the preparation of complexes, which were characterized by physical methods. Tablet containing resin with high degree of crosslinking showed buoyancy lag time (BLT) of 5-8 min. Decreasing the particle size of resin showed decrease in water uptake and drug release, with no significant effect on the rate of complexation and in situ complex formation for both preformed complexes (PCs) and physical mixtures (PMs). Thus, low-density and high degree of crosslinking of resin and water uptake may be the governing factor for controlling the initial release of tablet containing PMs but not in situ complex formation. However, further sustained release may be due to in situ complex formation.

  6. Ion-exchange chromatography for the characterization of biopharmaceuticals.

    Science.gov (United States)

    Fekete, Szabolcs; Beck, Alain; Veuthey, Jean-Luc; Guillarme, Davy

    2015-09-10

    Ion-exchange chromatography (IEX) is a historical technique widely used for the detailed characterization of therapeutic proteins and can be considered as a reference and powerful technique for the qualitative and quantitative evaluation of charge heterogeneity. The goal of this review is to provide an overview of theoretical and practical aspects of modern IEX applied for the characterization of therapeutic proteins including monoclonal antibodies (Mabs) and antibody drug conjugates (ADCs). The section on method development describes how to select a suitable stationary phase chemistry and dimensions, the mobile phase conditions (pH, nature and concentration of salt), as well as the temperature and flow rate, considering proteins isoelectric point (pI). In addition, both salt-gradient and pH-gradient approaches were critically reviewed and benefits as well as limitations of these two strategies were provided. Finally, several applications, mostly from pharmaceutical industries, illustrate the potential of IEX for the characterization of charge variants of various types of biopharmaceutical products. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Wastewater treatment with ion-exchange chitin membrane

    International Nuclear Information System (INIS)

    Paulenova, A.; Fjeld, R. A.; Visacky, V.

    2001-01-01

    Chitin, poly(N-acetyl-D glucosamine) and chitosan, its deacetylated derivates have recently obtained attention as bio-sorbents, because they shown a great ability to accumulate heavy metals and other pollutants. It was found that recovery of metals is strongly affected by pH. At low acidic pH range 4-5 chitin membrane exhibits better selectivity for lead than for cadmium or zinc. Sorption preference for metals decreases in the order: Pb > Cd > Zn. For uranium, as well for strontium was observed significant increase of recovery at decrease of pH to slightly acidic, close to neutral value. It was shown that chemical behavior of chitin membrane is excellent; ion-exchange nature of chitin was not changed during chitin membrane manufacturing process. Using of chitin membrane instead of chitin flake column brings significant increasing of driving force of the separation process, limited in the case of column experimental design by diffusion coefficient, while in the case of membrane process only by mass transfer coefficient. (authors)

  8. Supercritical water oxidation of ion exchange resins: Degradation mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Leybros, A.; Roubaud, A. [CEA Marcoule, DEN DTCD SPDE LFSM, F-30207 Bagnols Sur Ceze (France); Guichardon, P. [Ecole Cent Marseille, F-13451 Marseille 20 (France); Boutin, O. [Aix Marseille Univ, UMR CNRS 6181, F-13545 Aix En Provence 4 (France)

    2010-07-01

    Spent ion exchange resins are radioactive process wastes for which there is no satisfactory industrial treatment. Supercritical water oxidation could offer a viable treatment alternative to destroy the organic structure of resins and contain radioactivity. IER degradation experiments were carried out in a continuous supercritical water reactor. Total organic carbon degradation rates in the range of 95-98% were obtained depending on operating conditions. GC-MS chromatography analyses were carried out to determine intermediate products formed during the reaction. Around 50 species were identified for cationic and anionic resins. Degradation of poly-styrenic structure leads to the formation of low molecular weight compounds. Benzoic acid, phenol and acetic acid are the main compounds. However, other products are detected in appreciable yields such as phenolic species or heterocycles, for anionic IERs degradation. Intermediates produced by intramolecular rearrangements are also obtained. A radical degradation mechanism is proposed for each resin. In this overall mechanism, several hypotheses are foreseen, according to HOO center dot radical attack sites. (authors)

  9. Exchange of charges between fast ions and neutral atoms; Change de charges entre ions rapides et atomes neutres

    Energy Technology Data Exchange (ETDEWEB)

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

    1955-07-01

    In this paper, we summarize the most significant theoretical and experimental results obtained so far on the exchange of charges between fast ions and neutral atoms. (author) [French] Dans l'expose qui suit, nous resumons les resultats theoriques et experimentaux interessants obtenus jusqu'a nos jours dans le domaine de l'echange de charges entre ions rapides et atomes neutres. (auteur)

  10. Use of the ion exchange method for determination of stability constants of uranyl ions with three soil humic acids

    International Nuclear Information System (INIS)

    Tao Zuyi; Du Jinzhou

    1994-01-01

    The ion exchange equilibrium method proposed by Ardakani and Stevenson has not been widely used to determine the stability constants of metal-soil organic matter complexes. In this paper the Ardakani-Stevenson's method has been modified and the stability constants of uranyl ion complexes with three soil humic acids were determined by using the modified Ardakani-Stevenson's method. (orig.)

  11. Thermal Modeling Analysis Of CST Media In The Small Column Ion Exchange Project

    International Nuclear Information System (INIS)

    Lee, S.

    2010-01-01

    Models have been developed to simulate the thermal characteristics of Crystalline Silicotitanate (CST) ion exchange media fully loaded with radioactive cesium in a column configuration and distributed within a waste storage tank. This work was conducted to support the Small Column Ion Exchange (SCIX) program which is focused on processing dissolved, high-sodium salt waste for the removal of specific radionuclides (including Cs-137, Sr-90, and actinides) within a High Level Waste (HLW) storage tank at the Savannah River Site. The SCIX design includes CST columns inserted and supported in the tank top risers for cesium removal. Temperature distributions and maximum temperatures across the column were calculated with a focus on process upset conditions. A two-dimensional computational modeling approach for the in-column ion-exchange domain was taken to include conservative, bounding estimates for key parameters such that the results would provide the maximum centerline temperatures achievable under the design configurations using a feed composition known to promote high cesium loading on CST. One salt processing scenario includes the transport of the loaded (and possibly ground) CST media to the treatment tank floor. Therefore, additional thermal modeling calculations were conducted using a three-dimensional approach to evaluate temperature distributions for the entire in-tank domain including distribution of the spent CST media either as a mound or a flat layer on the tank floor. These calculations included mixtures of CST with HLW sludge or loaded Monosodium Titanate (MST) media used for strontium/actinide sorption. The current full-scale design for the CST column includes one central cooling pipe and four outer cooling tubes. Most calculations assumed that the fluid within the column was stagnant (i.e. no buoyancy-induced flow) for a conservative estimate. A primary objective of these calculations was to estimate temperature distributions across packed CST beds

  12. Inorganic ion-exchangers for the treatment and disposal of industrial effluents

    International Nuclear Information System (INIS)

    Hasany, S.M.

    2000-01-01

    Ion-exchangers can be broadly classified into organic and inorganic ion-exchangers. Inorganic ion-exchangers are stable at high temperatures and radiation dosage, resistant towards oxidizing agents and organic solvents. They are cheap and easy to prepare. Inorganic ion-exchangers, due to their superiority over organic ion-exchangers, have been extensively used for a wide variety of applications including treatment and management of industrial effluents. The criteria governing the division into essential and toxic elements for animal life have been described. The occupational sources of toxic elements and their compounds in the environment have been identified and their tolerance limits prescribed in air, water and food are given. The toxicity and adverse effects of harmful elements and their hazardous compounds are mentioned. Factors influencing sorption of trace elements onto inorganic ion-exchangers are highlighted. Examples of inorganic ion-exchangers are cited where they can be utilized for the treatment of industrial effluents before their safe discharge into waterways and biosphere. (author)

  13. Investigation of the resistance of some naturally occurring and synthetic inorganic ion exchangers against gamma radiation

    International Nuclear Information System (INIS)

    Nilchi, A.; Khanchi, A.; Ghanadi Maragheh, M.; Bagheri, A.

    2003-01-01

    The effect of various doses of gamma radiation on the ion-exchange capacity, distribution coefficient values, elution behaviour, physical effect, pH titration and infrared spectra of some synthetic inorganic ion exchangers, namely the cerium substituted phosphates; and naturally occurring inorganic ion exchangers, zeolites from different parts of Iran, have been studied systematically. No significant change has been observed in the ion-exchange capacity (with the exception of CeP(Na), CeP(Di·Na) and zeolite 5 (deposits of arababad talas)), elution behaviour, physical effect, chemical stability and the infrared spectra of the synthetic ion exchangers irradiated up to a total dose of 200 kGy, while a change has been observed in the pH-titration and distribution behaviour. The increase in pH is sharper for irradiated samples with divalent cations than for the normal samples. Furthermore, the K d values, and hence the selectivity towards certain cations increase with the total dose absorbed, reaching its optimum selectivity with the dose of 50-100 kGy. The natural zeolites chosen for these studies, show, similar pattern to those of synthetic ion exchangers, and in some cases an extremely high selectivity toward certain cations, like Be II . These make, zeolites, which are naturally occurring ion exchangers more viable economically, and extremely useful alternative in this industry

  14. Separation of uranium from sodium carbonate - sodium bicarbonate eluate by ion exchange method

    International Nuclear Information System (INIS)

    Sakane, Kohji; Hirotsu, Takahiro; Fujii, Ayako; Katoh, Shunsaku; Sugasaka, Kazuhiko

    1982-01-01

    The ion exchange method was used for separating uranium from the eluate (0.5 N Na 2 CO 3 -0.5 N NaHCO 3 ) that was obtained in the extraction process of uranium from natural sea water by using the titanium-activated carbon composite adsorbent. Uranium in the eluate containing 3 mg/1 uranium was adsorbed by ion exchange resin (Amberlite IRA-400), and was eluted with the eluant (5 % NaCl-0.5 % Na 2 CO 3 ). The concentration ratio of uranium in the final concentrated-eluate became more than 20 times. The eluting solution to the adsorbent and the eluant to the resin could be repeatedly used in the desorption-ion exchange process. Sodium carbonate was consumed at the desorption step, and sodium bicarbonate was consumed at the ion exchange step. The concentration ratio of uranium was found to decrease as chloride ion in the eluate increased. (author)

  15. Separation of uranium from sodium carbonate-sodium bicarbonate eluate by ion exchange method

    International Nuclear Information System (INIS)

    Sakane, Kohji; Hirotsu, Takahiro; Fujii, Ayako; Katoh, Shunsaku; Sugasaka, Kazuhiko

    1982-01-01

    The ion exchange method was used for separating uranium from the eluate (0.5 N Na 2 CO 3 -0.5 N NaHCO 3 ) that was obtained in the extraction process of uranium from natural sea water by using the titanium-activated carbon composite adsorbent. Uranium in the eluate containing 3 mg/l uranium was adsorbed by ion exchange resin (Amberlite IRA-400), and was eluted with the eluent (5% NaCl-0.5% Na 2 CO 3 ). The concentration ratio of uranium in the final concentrated-eluate became more than 20 times. The eluting solution to the adsorbent and the eluant to the resin could be repeatedly used in the desorption-ion exchange process. Sodium carbonate was consumed at the desorption step, and sodium bicarbonate was consumed at the ion exchange step. The concentration ratio of uranium was found to decrease as chloride ion in the eluate increased. (author)

  16. Study of the Fixation and Migration of Radioactive Cations in a Natural Ion Exchanger; Etude de la Fixation et de la Migration de Cations Radioactifs dans un Echangeur d'Ions Naturel; 0418 0417 0423 0427 0415 0414 ; Estudio de la Fijacion y de la Migracion de Cationes Radiactivos en un Cambiador Natural de Iones

    Energy Technology Data Exchange (ETDEWEB)

    Baetsle, L. [Centre d' Etudes de l' Energie Nucleaire, Mol (Belgium)

    1960-07-01

    With a view to utilizing lignite as a natural ion exchanger in the treatment of radioactive waste, a study was made of its physical and physico-chemical properties with reference to ion exchange. The distribution of Sr{sup 90} and Cs{sup 137} ions in the presence of Ca, Na and H was first examined and the equilibrium constants calculated. The kinetics and fixation of ions were then studied, and various parameters required for the calculation of ion-exchange beds were established. Study of the complex phenomenon of radioactive ion migration in the soil was started by the separate investigation of each component ionic equilibrium. (author) [French] Afin d'utiliser le lignite comme echangeur d'ions naturel dans le traitement d'eaux residuaires radioactives, uene etude a ete faite de ses proprietes physiques et physiochimiques, ayant trait a l'echange d'ions. En premier lieu on a etudie la distribution des ions {sup 90}Sr et {sup 137}Cs en presence de Ca, Na et H, et calcule les constantes d'equilibre. En second heu on a traite la cinetique de la fixation des ions, et etabli quelques parametres necessaires au calcul de hts d'echangeurs d'ions. L'etude du phenomene complexe de la migration des ions radioactifs dans le sol a ete abordee par l 'investigation separee de chacun des equilibres ioniques composants. (author) [Spanish] Con objeto de utilizar el lignito como cambiador natural de iones en el tratamiento de aguas residuales radiactivas, se han estudiado sus propiedades fisicas y fisicoquimicas en relacion con el intercambio de iones. En primer lugar, el autor ha estudiado la distribucion de los iones {sup 90}Sr y {sup 137}Cs en presencia de Ca, Na y H, y ha calculado las constantes de equilibrio. En segundo lugar ha estudiado la cinetica de la fijacion de iones y ha establecido algunos parametros necesarios para calcular los lechos de cambiadores de iones. El autor ha abordado el estudio del complejo fenomeno de la migracion de iones radiactivos en el suelo

  17. Silicon-CsI detector array for heavy-ion reactions

    CERN Document Server

    Norbeck, E; Pogodin, P I; Cheng, Y W; Ingram, F D; Bjarki, O; Grévy, S; Magestro, D J; Molen, A M V; Westfall, G D

    2000-01-01

    An array of 60 silicon-CsI(Tl) detector telescopes has been developed along with associated electronics. The close packing of the telescopes required novel designs for the photodiodes and the silicon DELTA E detectors. Newly developed electronics include preamplifiers, shaping amplifiers, test pulse circuitry, and a module to monitor leakage currents in the silicon diodes. The array covers angles from 5 deg. to 18 deg. in the 4 pi Array at the National Superconducting Cyclotron Laboratory at Michigan State University. It measures protons to 150 MeV and has isotopic resolution for intermediate mass nuclei.

  18. Intercalation of gaseous thiols and sulfides into Ag+ ion-exchanged aluminum dihydrogen triphosphate.

    Science.gov (United States)

    Hayashi, Aki; Saimen, Hiroki; Watanabe, Nobuaki; Kimura, Hitomi; Kobayashi, Ayumi; Nakayama, Hirokazu; Tsuhako, Mitsutomo

    2005-08-02

    Ag(+) ion-exchanged layered aluminum dihydrogen triphosphate (AlP) with the interlayer distance of 0.85 nm was synthesized by the ion-exchange of proton in triphosphate with Ag(+) ion. The amount of exchanged Ag(+) ion depended on the concentration of AgNO(3) aqueous solution. Ag(+) ion-exchanged AlP adsorbed gaseous thiols and sulfides into the interlayer region. The adsorption amounts of thiols were more than those of sulfides, thiols with one mercapto group > thiol with two mercapto groups > sulfides, and depended on the amount of exchanged Ag(+) ion in the interlayer region. The thiols with one mercapto group were intercalated to expand the interlayer distance of Ag(+) ion-exchanged AlP, whereas there was no expansion in the adsorption of sulfide. In the case of thiol with two mercapto groups, there was observed contraction of the interlayer distance through the bridging with Ag(+) ions of the upper and lower sides of the interlayer region.

  19. Treatment of Simulated Soil Decontamination Waste Solution by Ferrocyanide-Anion Exchange Resin Beads

    Energy Technology Data Exchange (ETDEWEB)

    Won, Hui Jun; Kim, Min Gil; Kim, Gye Nam; Jung, Chung Hun; Park, Jin Ho; Oh, Won Zin [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2005-03-15

    Preparation of ferrocyanide-anion exchange resin and adsorption test of the prepared resin on the Cs{sup -} ion were performed. Adsorption capability of the prepared resin on the Cs{sup -} ion in the simulated citric acid based soil decontamination waste solution was 4 times greater than that of the commercial cation exchange resin. Adsorption equilibrium of the prepared resin on the Cs{sup -} ion reached within 360 minutes. Adsorption capability on the Cs{sup -} ion became to decrease above the necessary Co{sup 2-} ion concentration in the experimental range. Recycling test of the spent ion exchange resin by the successive application of hydrogen peroxide and hydrazine was also performed. It was found that desorption of Cs{sup -} ion from the resin occurred to satisfy the electroneutrality condition without any degradation of the resin.

  20. Electrical Resistance and Transport Numbers of Ion-Exchange Membranes Used in Electrodialytic Soil Remediation

    DEFF Research Database (Denmark)

    Hansen, Henrik; Ottosen, Lisbeth M.; Villumsen, Arne

    1999-01-01

    Electrodialytic soil remediation is a recently developed method to decontaminate heavy metal polluted soil using ion-exchange membranes. In this method one side of the ion-exchange membrane is in direct contact with the polluted soil. It is of great importance to know if this contact with the soil...... different electrodialytic soil remediation experiments. The experiments showed that after the use in electrodialytic soil remediation, the ion-exchange membranes had transport numbers in the same magnitude as new membranes. The electrical resistance for six membranes did not differ from that of new...

  1. Ion exchange system design for removal of heavy metals from acid mine drainage wastewater

    Directory of Open Access Journals (Sweden)

    R. S. Sapkal

    2010-11-01

    Full Text Available This paper discusses the methodology used to determine the optimal ion-exchange column size to process all separate batchesof feeds from acid mine drainage wastewater.The optimal design ensures the best utilization of resin material and therefore results in a minimum amount of spent resins.Ion exchanger materials have been studied for removing heavy metals from a metal bearing wastes. For the current treatment,a facility has been designed for the removal of heavy metals from the acid mine drainage (AMD waste by the ion-exchange technology.

  2. Electrospun Zeolite/Cellulose Acetate Fibers for Ion Exchange of Pb2+

    Directory of Open Access Journals (Sweden)

    Daniel N. Tran

    2014-12-01

    Full Text Available The ion exchange capability of electrospun cellulose acetate (CA fibers containing zeolite A nanoparticles is reported. Solid and porous CA fibers were used to make a zeolite-embedded filter paper, which was then used to ion exchange Na+ with Cu2+ and Pb2+. The composite Linde Type A (LTA zeolite CA fibers exchanged 0.39 mmol/g more Pb2+ than LTA nanoparticles in the solid CA fibers. These fibers could provide a simple and effective method for heavy metal ion removal in water.

  3. Scandium sorption by immobilized microdispersed forms of phosporus-containing ion exchangers

    International Nuclear Information System (INIS)

    Sokolova, Yu.V.; Kurdyumov, G.M.; Smirnov, A.V.; Mezhirov, M.S.

    1991-01-01

    The possibility to improve considerably kinetics of scandium sorption by phosphate ion exchangers, immobilized into polyacrylonitrile (PAN) fibers, as compared with granular samples of ion exchangers, was shown. The influence of dispersion degree of immobilized ionite particles on sorption rate was studied. It is ascertained that the ionite grinding to the particle size ≤ 52 μm is sufficient for the rate increase by 1-1.5 orders. A lower swelling of the immobilized ion exchanger is its additional advantage as compared with granular form

  4. Advance in the study of removal of cesium from radioactive wastewater by inorganic ion exchangers

    International Nuclear Information System (INIS)

    Wang Songping; Wang Xiaowei; Du Zhihui

    2014-01-01

    The excellent performance in the removal of cesium from radioactive wastewater by inorganic ion exchangers has received extensive attention due to their characteristic physico-chemical features. The paper summarized research progress of removal of cesium by different inorganic ion exchangers such as silicoaluminate, salts of hetero polyacid, hexacyanoferrate, insoluble salts of acid with multivalent metals, insoluble hydrous oxides of multivalent metals and silicotitanate and reviewed several removal systems of cesium by inorganic ion exchangers which might offer China some reference in treatment and disposal of radioactive wastewater. (authors)

  5. Separation of boron isotopes by ion exchange chromatography: studies with Duolite-162, a type-II resin

    International Nuclear Information System (INIS)

    Sharma, B.K.; Subramanian, R.; Balasubramanian, R.; Mathur, P.K.

    1994-01-01

    The selection of resin plays an important role in the process of separation of boron isotopes by ion exchange chromatography. The determination of (i) ion exchange capacity of Duolite-162 resin for hydroxyl - chloride exchange, (ii) hydroxyl - borate exchange, (iii) isotopic exchange separation factor by batch method and (iv) effect of concentration of boric acid on isotopic exchange separation factor to test the suitability of the above resin for this process are discussed in this report. (author)

  6. Isotopic exchange rate of sodium ions between hydrous metal oxides and aqueous solutions

    International Nuclear Information System (INIS)

    Inoue, Yasushi; Yamazaki, Hiromichi

    1991-01-01

    To elucidate the kinetics of ion-exchange reaction on hydrous metal oxide, the isotopic exchange rates of sodium ions between hydrous metal oxides such as hydrous tin (IV), niobium (V), zirconium (IV) and titanium (IV) oxides, and aqueous solutions were measured radiochemically and compared with each other. The rate of reaction cannot be understood by an unified view since the rate controlling step differs with the kind of exchangers. The rate constants relevant to each exchanger such as diffusion constants and their activation energies were also determined. (author)

  7. Possibility of ion-exchange column studies using stabilised montmorillonite-H aggregates

    International Nuclear Information System (INIS)

    Platzer, R.; Bittel, R.

    1959-01-01

    The conditions necessary for obtaining stable aggregates of montmorillonite-H, prepared without addition of organic flocculant, is discussed. These aggregates possess the same general ion-exchange properties as montmorillonite-H suspensions, about which many papers have been written. Their insolubility and their stable physical form enable them to be used in columns in exactly the same way as the usual organic ion exchangers. The examples of cation fixation and separation described in this report emphasize the similarities between the properties of this exchanger and those of organic cation-exchange resins, and open up possibilities for the extrapolation of the many investigations carried out on organic exchangers to mineral exchangers of this type. Amongst the essential differences to be remarked, we have shown that the properties of physical stability and chemical exchange remain the same at temperatures up to 300 deg. C, to a first approximation, under very intense γ irradiation. (author) [fr

  8. The induction of genomic instability in related human lymphoblasts following exposure to Cs gamma radiation vs accelerated 56Fe Ions

    International Nuclear Information System (INIS)

    Evans, H.H.; Horng, M.-F.; Ricanati, M.; Diaz-Insua, M.

    2003-01-01

    Full text: The induction of genomic instability by exposure to Cs-137 gamma radiation and Fe-56 accelerated ions was investigated by measuring the frequency and characteristics of TK6 and WTK1 unstable clones isolated 36 generations after exposure. While the two cell lines are related, TK6 is more sensitive to radiation, has normal p53 expression, and is repair deficient. Clones surviving the radiation and respective controls were analyzed for 17 characteristics including chromosomal aberrations, growth defects, alterations in response to a second radiation and mutant frequencies at two different loci. Putative unstable clones were defined as those exhibiting a significant alteration in one or more characteristics as compared to the respective control medians. Over half of the unstable WTK1 clones and over 90% of the TK6 unstable clones surviving exposure to either radiation exhibited chromosomal instability, the major aberrations consisting of chromatid breaks and dicentric chromosomes formed by end-to-end fusions. Alterations in the other measured characteristics occurred much less often than cytogenetic alterations in the TK6 unstable clones. The phenotype of the WTK1 unstable clones was more diverse and complex than in the case of TK6 unstable clones. The phenotype of the TK6 unstable clones differed in the survivors of Cs-137 vs. Fe-56. In the clones surviving Cs-137, the aberrations consisted mainly of dicentric chromosomes, while clones surviving exposure to Fe-56 exhibited both breaks and dicentrics. The uniform prevalence of chromosomal aberrations in the unstable TK6 clones vs. the relatively diverse phenotype of the unstable WTK1 clones suggests that the deficiency in DNA double-strand break repair in TK6 cells may be accompanied by a deficiency in telomere maintenance that leads to telomere fusion, dicentric chromosomes, anaphase bridges, breakage and the occurrence of chromosomal instability in the majority of clones isolated following exposure

  9. Separation of boron isotopes by ion exchange chromatography: studies on regeneration of strong base anion exchange resins

    International Nuclear Information System (INIS)

    Sharma, B.K.; Subramanian, R.; Mathur, P.K.

    1994-01-01

    The optimum conditions for the regeneration of strong base anion exchange resins of type-I and type-II were determined for cost-effective separation of isotopes of boron by ion exchange chromatography where the hydroxyl form of an anion exchange resin is equilibrated with boric acid solution containing mannitol as a complexing reagent. The possibility of using unspent alkali content of the effluent was also exploited. Removal of carbonate impurity from Rayon grade caustic lye (used as regenerant after dilution) and recycling of Ba(OH) 2 was studied to avoid waste disposal problems. (author)

  10. Desirable levels of exchangeable K and Ca and their concentration in the soil solution to reduce uptake of radioactive Cs by rice plants

    International Nuclear Information System (INIS)

    Sekimoto, Hitoshi; Yamada, Takashi; Hotsuki, Tomoe; Matsuzaki, Akio; Mimura, Tetsuro

    2014-01-01

    K in the soil solution can control the uptake of radioactive Cs by rice plants, but this control is not accomplished only by K; it is affected by other ionic species. It is therefore important to investigate uptake of radioactive Cs from the perspective of the concentration of major cations such as Ca in the soil solution and the levels of exchangeable cations in the soil. To clarify the effects of K and Ca in the soil solution and of the levels of soil exchangeable cations to prevent uptake of radioactive Cs, we conducted a pot experiment and field experiments in a paddy soil in 2011 and 2012. To reduce the uptake of radioactive Cs, it was necessary to achieve a K concentration in the soil solution of 0.5 mmol L"-"1, and a Ca concentration higher than 2 mmol L"-"1 based on the results of the pot experiment. In addition, we obtained the desirable levels of exchangeable cations and the cation exchange capacity (CEC) in the soil from previous reports and the results of our field experiments. On this basis, we propose the following threshold levels for exchangeable cations and CEC in the soil as a standard: 0.53 K cmol_c kg"-"1, 18.0 Ca cmol_c kg"-"1, 2.0 Mg cmol_c kg"-"1, i.e. 25 mg K_2O 100 g"-"1, 505 mg CaO 100 g"-"1, 40 Mg O mg 100 g"-"1, and a CEC of 30 cmol_c kg"-"1. Converting these values into the corresponding levels in the soil solution, we obtained concentrations of 0.71 mmol K L"-"1, 4.22 mmol Ca L"-"1, and 1.35 mmol Mg L"-"1. These levels are within the improving standard for fertility of paddy soils in Japan. Consequently, it will be necessary to improve the fertility of paddy soils to control the uptake of radioactive Cs by rice plants. (author)

  11. Bituminous solidification, disposal, transport and burial of spent ion-exchange resins. Part of a coordinated programme on treatment of spent ion exchange resins

    International Nuclear Information System (INIS)

    Mozes, G.; Kristof, M.

    1983-07-01

    The project dealing with the incorporation of spent ion-exchange resins into bitumen was performed within the Agency coordinated research programme on treatment of spent ion-exchange resins. Physical and chemical properties of commercial ion-exchange resins, bitumens and bituminized resins were studied. It was shown that bitumen with low oil content and with a softening point of 60-70 deg. C are applicable for the incorporation of resins. The final waste form is allowed to contain maximum 50% resin. The comprehensive study of the biological resistance of B-30 bitumen was performed. That showed that any bacteriological attack can be regarded as generally insignificant. A continuously operating technology was realized on a semi-plant scale. The best operating conditions of this technology were determined. On the basis of the experience gained from the experiments a design of the bituminization plant of 50m 3 dry resin/year treatment capacity was proposed

  12. Wetting of bituminized ion-exchangers under simulated repository conditions

    International Nuclear Information System (INIS)

    Aalto, H.; Valkiainen, M.

    2001-01-01

    According to the present plans the spent nuclear fuel from four Finnish nuclear power units will be transferred after interim storage to the final disposal site where it will be encapsulated and disposed of in a final repository constructed into the bedrock at a depth of 500 meters. Low and medium level waste generated at nuclear power plants will be finally disposed of in caverns constructed in the bedrock at the power plant site. The safety of the final disposal is based on a multibarrier concept and the degree of safety is estimated by using predictive models. The properties of the waste form are taken into account in the design of the repository construction. Bitumen has been chosen as an immobilisation agent for the wet wastes at Olkiluoto Power Plant, where two BWR units, TVO 1 and TVO 2, have separate bituminization facilities designed by Asea-Atom. Properties of bituminized spent ion-exchange resins from Olkiluoto power plant have been studied by VTT Chemical Technology since the late 70's. These studies have concentrated mainly on determining the long-term behaviour of the bituminization product under the repository conditions. Current interest lies on wetted product as a diffusion barrier. For this purpose a microscopic method for the visualisation of the structure of the wetted product has been developed. The equilibration of the samples in simulated concrete groundwater is currently going on at a temperature of 5-8 deg. C. Preliminary results are presented in this paper. Diffusion experiments have been planned for the further characterising of the wetted product as a release barrier for radionuclides including modelling. (author)

  13. Problems and remedy programme of an ion-exchange filter

    International Nuclear Information System (INIS)

    Khattab, M.; Mekhemar, S.

    1994-01-01

    Practical problems of the ion exchange filter of ET-R R-1 reactor are discussed. Remedy program is described. The program includes:- Evaluating the efficiency of the resins. -Discharging of the radio-active resins from the filter - Identification of corrosion and repairing process of the filter vessel - Charging process of the fresh resins. -Evaluating the efficiency of the new resins. Waste radio-active resins were discharged by siphon effect. The chloride content in reactor cooling water decreased from 5.8 ppm to 1.1 ppm after changing the resins. Nevertheless, the chloride content is still much higher than the standard value 0.05 ppm. This is due to the high level of the chloride in the demineralized water produced by the demineralizer, 0.8 ppm. Therefore, it is recommended that the resins of the mixed bed demineralizer be tailored to produce the standard water quality. The filter vessel cannot be quarantined to be in good service condition for a long period. The vessel should be replaced by a new design which would facilitate the process of discharging the radioactive resins and charging the fresh resins. The inner surface of the vessel should be coated or cladded to withstand the aggressive environment of the water. Periodical water chemical analysis is necessary to investigate reactor coolant and filter conditions. The aging effect of the stored water supply to the reactor should be taken into consideration. New demineralized should be installed near the feed water supply tanks so that the stored water could be refreshed. The device save the costs of production of fresh demineralized water. Development of radioactive waste transportation mechanisms and storing are necessary. 12 figs., 4 tabs

  14. The application of synthetic inorganic ion exchangers to analytical chemistry, 2

    International Nuclear Information System (INIS)

    Abe, Mitsuo

    1974-01-01

    Regarding acidic salts, description is made on the general behaviour of the acidic salts of tetravalent metals and each of zirconium salts, titanium salts, stannic salts, cerium salts, thorium salts, chromium salts, and others. On heteropolyacid salts, ammonium 12-molybdophosphated and phosphorus wolframate are described. On insoluble ferrocyanides, the behaviour of various complex salts is explained. In the discussion on the general behaviour of the acidic salts of tetravalent metals, the ideality of ion exchange, the stability and solubility of the acidic salts, thermal stability and radiation resistance, the ion sieving effect of various acidic salts, and the selectivity of the acidic salts are stated. Zirconium gives a number of acidic salts, such as zirconium phosphate, crystalline zirconium phosphate, zirconium phrophosphate, various polyphosphates of zirconium, zirconium phosphate-silicate, zirconium arsenate, zirconium antimonate, zirconium molybdate, zirconium tungstate, etc. Useful titanium salts for ion exchange are titanium phosphate, titanium aresenate, titanium antimonate, titanium tungstate, titanium molybdate, titanium vanadate, and titanium selenate. The distribution coefficients of metal ions, inorganic-separation of various inorganic ion exchangers, the exchange characteristics of various elements on various ion exchangers, and the selectivity of various inorganic ion-exchangers are tabulated. (Fukutomi, T.)

  15. 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)

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

    International Nuclear Information System (INIS)

    Tawfic, A.F.; Dickson, S.E.; Kim, Y.; Mekky, W.

    2015-01-01

    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)

  17. Sorption and migration of 137Cs attached to organic materials of tea in silty clay soil

    International Nuclear Information System (INIS)

    Yuecel, H.; Oezmen, A.

    1996-01-01

    The effect of the organic material of tea on the adsorption behavior of 137 Cs on the silty clay soil has been examined by batch experiments, using 137 Cs extracted tea contaminated by the Chernobyl accident, with water. The variation of K d values was studied as a function of contact time and a volume-solid ratio (V/m). The equilibrium time of 137 Cs extracted from the tea is slower by 9 times than that of 137 Cs + ions for the silty clay soil. The V/m ratio did not affect the 137 Cs adsorption strongly. The sorption of 137 Cs extracted form the tea in terms of the distribution coefficient K d is higher (a factor of 2.5) than that of 137 Cs + ions. This result indicates that 137 Cs-complexes with organic materials of tea are much sorbed than 137 C + ions on the silty clay soil. The migration of 137 Cs extracted from the tea in the silty clay soil has been studied under a steady flow of tea-extract by using a soil zone apparatus. The 137 Cs concentrations contained in both effluent fractions and in soil samples were measured using a HPGe detector. The distribution patterns of 137 Cs in the layers of the soil zone were obtained as one- and two-dimensional. The migration of 137 Cs extracted from the tea in soil is mainly influenced by flow. The results indicate that the migration of 137 Cs-complexes with organic materials and 137 Cs adsorbed fine silts cannot be described by such a K d based on ion-exchange reactions, but it is important to consider the moving mechanism of particulates besides ion-exchange reactions. (Author)

  18. Treatment of low level radioactive liquid wastes using composite ion-exchange resins based on polyurethane foam

    International Nuclear Information System (INIS)

    Rao, S.V.S.; Lekshmi, R.; Mani, A.G.S.; Sinha, P.K.

    2010-01-01

    Composite ion-exchange resins were prepared by coating copper-ferrocyanide (CFC) and hydrous manganese oxide (HMO) powders on polyurethane (PU) foam. Polyvinyl acetate/Acetone was used as a binder. The foam was loaded with about five times its weight with CFC and HMO powders. The distribution coefficients of CFC-PU foam and HMO-PU foam for cesium and strontium respectively were estimated. Under similar conditions the HMO-PU foam showed higher capacity as well as better kinetics for removal of strontium than CFC-PU foam for Cs. The pilot plant scale studies were conducted using a mixed composite ion-exchange resin bed. About 1000 bed volumes could be passed before attaining a DF of 10 from an initial value of 60-80. The spent resin was digested in alkaline KMnO 4 and the digested liquid was fixed in cement matrix. The matrices were characterized with respect to compressive strength and leach resistance. (author)

  19. Determination of γ-hydroxybutyrate in human urine samples by ion exclusion and ion exchange two-dimensional chromatography system.

    Science.gov (United States)

    Liu, Junwei; Deng, Zhifen; Zhu, Zuoyi; Wang, Yong; Wang, Guoqing; Sun, Yu-An; Zhu, Yan

    2017-12-15

    A two-dimensional ion chromatography system was developed for the determination of γ-hydroxybutyrate (GHB) in human urine samples. Ion exclusion chromatography was used in the first dimensional separation for elimination of urine matrices and detection of GHB above 10mgL -1 , ion exchange chromatography was used in the second dimensional separation via column-switching technique for detection of GHB above 0.08mgL -1 . Under the optimized chromatographic conditions, the ion exclusion and ion exchange chromatography separation system exhibited satisfactory repeatability (RSDchromatography system was convenient and practical for the determination of GHB in human urine samples. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Development Of An Approach To Modeling Loading And Elution Of Spherical Resorcinol Formaldehyde Ion-Exchange Resin

    International Nuclear Information System (INIS)

    Aleman, S.; Hamm, L.; Smith, F.

    2011-01-01

    The current strategy for removal of cesium from the Hanford waste stream is ion-exchange using spherical Resorcinol-Formaldehyde (sRF) resin. The original resin of choice was granular SuperLig 644 resin and during testing of this resin several operational issues were identified. For example, the granular material had a high angle of internal friction resulting in fragmentation of resin particles along its edges during cycling and adverse hydraulic performance. Efforts to replace SuperLig 644 were undertaken and one candidate was the granular Resorcinol-Formaldehyde (RF) resin where experience with this cation exchanger dates back to the late 1940's. To minimize hydraulic concerns a spherical version of RF was developed and several different chemically produced batches were created. The 5E-370/641 batch of sRF was selected and for the last decade numerous studies have been performed (e.g., batch contact tests, column loading and elution tests). The Waste Treatment Plant (WTP) flowsheet shows that the aqueous phase waste stream will have a wide range of ionic concentrations (e.g., during the loading step 0-3 M free OH, 5+ M Na, 0-1 M K, 0-3 M NO 3 ). Several steps are required in the ion-exchange process to achieve the required Cs separation factors: loading, displacement, washing, elution, and regeneration. The sRF resin will be operated over a wide range in pH (i.e., pH of 12-14 during the loading step and pH of 0.01-1 during the elution step). During some of these steps very high levels of counter-ions and co-ions will be present within the aqueous phase. Alternative process feeds are under consideration as well (e.g., sodium levels as high as 8 M and column operation up to 45 C during loading, reduced and recycled HNO 3 during elution). In order to model the performance of sRF resin through an entire ion-exchange cycle, a more robust isotherm model is required. To achieve this more robust isotherm model requires knowledge of the numbers and kinds of fixed