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Sample records for acidic cation-exchange resin

  1. Separation of aliphatic carboxylic acids and benzenecarboxylic acids by ion-exclusion chromatography with various cation-exchange resin columns and sulfuric acid as eluent.

    Science.gov (United States)

    Ohta, Kazutoku; Ohashi, Masayoshi; Jin, Ji-Ye; Takeuchi, Toyohide; Fujimoto, Chuzo; Choi, Seong-Ho; Ryoo, Jae-Jeong; Lee, Kwang-Pill

    2003-05-16

    The application of various hydrophilic cation-exchange resins for high-performance liquid chromatography (sulfonated silica gel: TSKgel SP-2SW, carboxylated silica gel: TSKgel CM-2SW, sulfonated polymethacrylate resin: TSKgel SP-5PW, carboxylated polymethacrylate resins: TSKgel CM-5PW and TSKgel OA-Pak A) as stationary phases in ion-exclusion chromatography for C1-C7 aliphatic carboxylic acids (formic, acetic, propionic, butyric, isovaleric, valeric, isocaproic, caproic, 2-methylhexanoic and heptanoic acids) and benzenecarboxylic acids (pyromellitic, trimellitic, hemimellitic, o-phthalic, m-phthalic, p-phthalic, benzoic, salicylic acids and phenol) was carried out using diluted sulfuric acid as the eluent. Silica-based cation-exchange resins (TSKgel SP-2SW and TSKgel CM-2SW) were very suitable for the ion-exclusion chromatographic separation of these benzenecarboxylic acids. Excellent simultaneous separation of these benzenecarboxylic acids was achieved on a TSKgel SP-2SW column (150 x 6 mm I.D.) in 17 min using a 2.5 mM sulfuric acid at pH 2.4 as the eluent. Polymethacrylate-based cation-exchange resins (TSKgel SP-5PW, TSKgel CM-5PW and TSKgel OA-Pak A) acted as advanced stationary phases for the ion-exclusion chromatographic separation of these C1-C7 aliphatic carboxylic acids. Excellent simultaneous separation of these C1-C7 acids was achieved on a TSKgel CM-5PW column (150 x 6 mm I.D.) in 32 min using a 0.05 mM sulfuric acid at pH 4.0 as the eluent.

  2. Synthesis, characterization and applications of a new cation exchanger tamarind sulphonic acid (TSA) resin.

    Science.gov (United States)

    Singh, A V; Sharma, Naresh Kumar; Rathore, Abhay S

    2012-01-01

    A new composite cation exchanger, tamarind sulphonic acid (TSA) resin has been synthesized. The chemically modified TSA ion exchange resin has been used for the removal and preconcentration of Zn2+, Cd2+, Fe2+, Co2+ and Cu2+ ions in aqueous solution and effluent from the Laxmi steel plant in Jodhpur, India. This type of composite represents a new class of hybrid ion exchangers with good ion exchange capacity, stability, reproducibility and selectivity for toxic metal ions found in effluent from the steel industry. The characterization of the resin was carried out by determining the ion-exchange capacity, elemental analysis, pH titration, Fourier transform infrared spectra and thermal analysis. The distribution coefficients (K(d)) of toxic metal ions were determined in a reference aqueous solution and the steel plant effluent at different pH values; the absorbency of different metal ions on the TSA resin was studied for up to 10 cycles. The adsorption of different metal ions on TSA resin follows the order: Co2+ > Cu2+ > Zn2+ > Fe2+ > Cd2+. The ion exchange capacity of TSA resin is 2.87%.

  3. Safety evaluation of cation-exchange resins

    International Nuclear Information System (INIS)

    Kalkwarf, D.R.

    1977-08-01

    Results are presented of a study to evaluate whether sufficient information is available to establish conservative limits for the safe use of cation-exchange resins in separating radionuclides and, if not, to recommend what new data should be acquired. The study was also an attempt to identify in-line analytical techniques for the evaluation of resin degradation during radionuclide processing. The report is based upon a review of the published literature and upon discussions with many people engaged in the use of these resins. It was concluded that the chief hazard in the use of cation-exchange resins for separating radionuclides is a thermal explosion if nitric acid or other strong oxidants are present in the process solution. Thermal explosions can be avoided by limiting process parameters so that the rates of heat and gas generation in the system do not exceed the rates for their transfer to the surroundings. Such parameters include temperature, oxidant concentration, the amounts of possible catalysts, the radiation dose absorbed by the resin and the diameter of the resin column. Current information is not sufficient to define safe upper limits for these parameters. They can be evaluated, however, from equations derived from the Frank-Kamenetskii theory of thermal explosions provided the heat capacities, thermal conductivities and rates of heat evolution in the relevant resin-oxidant mixtures are known. It is recommended that such measurements be made and the appropriate limits be evaluated. A list of additional safety precautions are also presented to aid in the application of these limits and to provide additional margins of safety. In-line evaluation of resin degradation to assess its safety hazard is considered impractical. Rather, it is recommended that the resin be removed from use before it has received the limiting radiation dose, evaluated as described above

  4. 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).

  5. 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)

  6. Cation exchange of 53 elements in nitric acid

    International Nuclear Information System (INIS)

    Marsh, S.F.; Alarid, J.E.; Hamond, C.F.; McLeod, M.J.; Roensch, F.R.; Rein, J.E.

    1978-02-01

    Cation-exchange distribution data are presented for 53 elements from 3 to 12M HNO 3 for three strong-acid resins, having cross-linkages of 8%, 4%, and macroporous. Data obtained by 16- to 18-h dynamic batch contacts are compared to cation-exchange distribution data from strong HCl and HClO 4

  7. Ion-exclusion chromatography with conductimetric detection of aliphatic carboxylic acids on a weakly acidic cation-exchange resin by elution with benzoic acid-beta-cyclodextrin.

    Science.gov (United States)

    Tanaka, Kazuhiko; Mori, Masanobu; Xu, Qun; Helaleh, Murad I H; Ikedo, Mikaru; Taoda, Hiroshi; Hu, Wenzhi; Hasebe, Kiyoshi; Fritz, James S; Haddad, Paul R

    2003-05-16

    In this study, an aqueous solution consisting of benzoic acid with low background conductivity and beta-cyclodextrin (beta-CD) of hydrophilic nature and the inclusion effect to benzoic acid were used as eluent for the ion-exclusion chromatographic separation of aliphatic carboxylic acids with different pKa values and hydrophobicity on a polymethacrylate-based weakly acidic cation-exchange resin in the H+ form. With increasing concentration of beta-cyclodextrin in the eluent, the retention times of the carboxylic acids decreased due to the increased hydrophilicity of the polymethacrylate-based cation-exchange resin surface from the adsorption of OH groups of beta-cyclodextrin. Moreover, the eluent background conductivity decreased with increasing concentration of beta-cyclodextrin in 1 mM benzoic acid, which could result in higher sensitivity for conductimetric detection. The ion-exclusion chromatographic separation of carboxylic acids with high resolution and sensitivity was accomplished successfully by elution with a 1 mM benzoic acid-10 mM cyclodextrin solution without chemical suppression.

  8. Uranium adsorption from the sulphuric acid leach liquor containing more chlorides with cation-exchange resin SL-406

    International Nuclear Information System (INIS)

    Hu Jun; Wang Zhaoguo; Chi Renqing; Niu Xuejun

    1994-01-01

    The feasibility of uranium adsorption was studied from the sulphuric acid leach liquor of a uranium ore containing more chlorides with cation-exchange resin SL-406. The influence of some factors on uranium adsorption was investigated. It was shown that the resin possesses better selectivity, stability and higher capacity. It can be effectively used to recovery uranium from leach liquors of uranium ores containing more chlorides

  9. Characteristics of floc formation 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 floc formation. The physical, chemical and electrochemical properties of powdered ion exchange resin were measured and the factors related to floc formation of anion and cation exchange resin were investigated by measuring the specific settle volume of resin floc as an evaluating index. It was found that these factors were mixing ratio, nature of resins and particle size of resins. In addition, it was assumed on the bases of these results that the amount of resin floc was related to sum of the surface electric charges of both resins. The filling ratio of resin floc was related to their product by multiplication and an experimental expression was obtained. The specific settle volume of resin floc could then be simulated by particle size, surface area, ion exchange capacity and degree of ionization of the powdered ion exchange resin. (author)

  10. Characteristics of floc formation 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 floc formation. The physical, chemical and electrochemical properties of powdered ion exchange resin were measured and the factors related to floc formation of anion and cation exchange resin were investigated by measuring the specific settle volume of resin floc as an evaluating index. It was found that these factors were mixing ratio, nature of resins and particle size of resins. In addition, it was assumed on the bases of these results that the amount of resin floc was related to sum of the surface electric charges of both resins. The filling ratio of resin floc was related to their product by multiplication and an experimental expression was obtained. The specific settle volume of resin floc could then be simulated by particle size, surface area, ion exchange capacity and degree of ionization of the powdered ion exchange resin. (author).

  11. Distribution of 14 elements from two solutions simulating Hanford HLW Tank 102-SY (acid-dissolved sludge and acidified supernate) on four cation exchange resins and five anion exchange resins having different functional groups

    International Nuclear Information System (INIS)

    Marsh, S.F.; Svitra, Z.V.; Bowen, S.M.

    1995-01-01

    As part of the Tank Waste Remediation System program at Los Alamos, we evaluated a series of cation exchange and anion exchange resins for their ability to remove hazardous components from radioactive high-level waste (HLW). The anion exchangers were Reillex TM HPQ, a polyvinyl pyridine resin, and four strong-base polystyrene resins having trimethyl, tri ethyl, tri propyl, and tributyl amine as their respective functional groups. The cation exchange resins included Amberlyst TM 15 and Amberlyst tM XN-1010 with sulfonic acid functionality, Duolite TM C-467 with phosphonic acid functionality, and poly functional Diphonix TM with di phosphonic acid, sulfonic acid, and carboxylic acid functionalities. We measured the distributions of 14 elements on these resins from solutions simulating acid-dissolved sludge (pH 0.6) and acidified supernate (pH 3.5) from underground storage tank 102-SY at the Hanford Reservation near Richland, Washington, USA. To these simulants, we added the appropriate radionuclides and used gamma spectrometry to measure fission products (Ce, Cs, Sr, Tc, and Y), actinides (U, Pu, and Am), and matrix elements (Cr, Co, Fe, Mn, Zn, and Zr). For each of the 252 element/resin/solution combinations, distribution coefficients (Kds) were measured for dynamic contact periods of 30 minutes, 2 hours, and 6 hours to obtain information about sorption kinetics from these complex media. Because we measured the sorption of many different elements, the tabulated results indicate which unwanted elements are most likely to interfere with the sorption of elements of special interest. On the basis of these 756 measured Kd values, we conclude that some of the tested resins appear suitable for partitioning hazardous components from Hanford HLW. (author). 10 refs., 11 tabs

  12. Use of a polystyrene-divinylbenzene-based weakly acidic cation-exchange resin column and propionic acid as an eluent in ion-exclusion/adsorption chromatography of aliphatic carboxylic acids and ethanol in food samples.

    Science.gov (United States)

    Mori, Masanobu; Hironaga, Takahiro; Kajiwara, Hiroe; Nakatani, Nobutake; Kozaki, Daisuke; Itabashi, Hideyuki; Tanaka, Kazuhiko

    2011-01-01

    We developed an ion-exclusion/adsorption chromatography (IEAC) method employing a polystyrene-divinylbenzene-based weakly acidic cation-exchange resin (PS-WCX) column with propionic acid as the eluent for the simultaneous determination of multivalent aliphatic carboxylic acids and ethanol in food samples. The PS-WCX column well resolved mono-, di-, and trivalent carboxylic acids in the acidic eluent. Propionic acid as the eluent gave a higher signal-to-noise ratio, and enabled sensitive conductimetric detection of analyte acids. We found the optimal separation condition to be the combination of a PS-WCX column and 20-mM propionic acid. Practical applicability of the developed method was confirmed by using a short precolumn with a strongly acidic cation-exchange resin in the H(+)-form connected before the separation column; this was to remove cations from food samples by converting them to hydrogen ions. Consequently, common carboxylic acids and ethanol in beer, wine, and soy sauce were successfully separated by the developed method.

  13. Ion exchange removal of chromium (iii) from tannery wastes by using a strong acid cation exchange resin amberlite ir-120 h+ and its hybrids

    International Nuclear Information System (INIS)

    Ahmad, T.

    2014-01-01

    A strong acid cation exchange resin Amberlite IR-120 H+ and its hybrids with Mn(OH)/sub 2/, Cu(OH)/sub 2/ and Fe(OH)/sub 3/ are used for the removal of chromium (III) from spent tannery bath. The experimental data give good fits with the Langmuir sorption model. The thermodynamic parameters entropy (delta S), enthalpy (delta H) and free energy (delta G) changes are computed, which reveal that the chromium removal from tannery wastes by ion exchangers is an endothermic, physical sorption and entropically driven process. The rate of sorption is found to increase with the increase of resin dosage, stirring speed and temperature. Different kinetic models such as film diffusion, particle diffusion and Lagergren pseudo first order are used to evaluate the mechanism of the process. It is found that the hybrid ion exchange resins have better removal capacity as compared to the parent ion exchanger. The increase in the removal capacity is found to be in the order of the corresponding PZC values of the hybrid ion exchangers. Further, it is suggested that the higher exchange capacity is the result of Donnan effect and specific adsorption of chromium by the oxides / hydroxides present inside the matrix of the organic cation exchanger. (author)

  14. Phenolic cation exchange resin material for recovery of cesium and strontium

    Science.gov (United States)

    Ebra, Martha A.; Wallace, Richard M.

    1983-01-01

    A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear waste solutions. The organic resins are condensation polymers of resorcinol and formaldehyde with attached chelating groups. The column performance of the resins compares favorably with that of commercially available resins for either cesium or strontium removal. By combining Cs.sup.+ and Sr.sup.2+ removal in the same bed, the resins allow significant reduction of the size and complexity of facilities for processing nuclear waste.

  15. HTGR fuel development: loading of uranium on carboxylic acid cation-exchange resins using solvent extraction of nitrate

    International Nuclear Information System (INIS)

    Haas, P.A.

    1975-09-01

    The reference fuel kernel for recycle of 233 U to HTGR's (High-Temperature Gas-Cooled Reactors) is prepared by loading carboxylic acid cation-exchange resins with uranium and carbonizing at controlled conditions. The purified 233 UO 2 (NO 3 ) 2 solution from a fuel reprocessing plant contains excess HNO 3 (NO 3 - /U ratio of approximately 2.2). The reference flowsheet for a 233 U recycle fuel facility at Oak Ridge uses solvent extraction of nitrate by a 0.3 M secondary amine in a hydrocarbon diluent to prepare acid-deficient uranyl nitrate. This nitrate extraction, along with resin loading and amine regeneration steps, was demonstrated in 14 runs. No significant operating difficulties were encountered. The process is controlled via in-line pH measurements for the acid-deficient uranyl nitrate solutions. Information was developed on pH values for uranyl nitrate solution vs NO 3 - /U mole ratios, resin loading kinetics, resin drying requirements, and other resin loading process parameters. Calculations made to estimate the capacities of equipment that is geometrically safe with respect to control of nuclear criticality indicate 100 kg/day or more of uranium for single nitrate extraction lines with one continuous resin loading contactor or four batch loading contactors. (auth)

  16. System for processing ion exchange resin regeneration waste liquid in atomic power plant

    International Nuclear Information System (INIS)

    Onaka, Noriyuki; Tanno, Kazuo; Shoji, Saburo.

    1976-01-01

    Object: To reduce the quantity of radioactive waste to be solidified by recovering and repeatedly using sulfuric acid and sodium hydroxide which constitute the ion exchange resin regeneration waste liquid. Structure: Cation exchange resin regeneration waste liquid is supplied to an anion exchange film electrolytic dialyzer for recovering sulfuric acid through separation from impurity cations, while at the same time anion exchange resin regeneration waste liquid is supplied to a cation exchange film electrolytic dialyzer for recovering sodium hydroxide through separation from impurity anions. The sulfuric acid and sodium hydroxide thus recovered are condensed by a thermal condenser and then, after density adjustment, repeatedly used for the regeneration of the ion exchange resin. (Aizawa, K.)

  17. Removal of radiocesium using cation exchange resin

    International Nuclear Information System (INIS)

    Morita-Murase, Yuko; Mizumura, Ryosuke; Tachibana, Yoshitaka; Kanazawa, Hideko

    2013-01-01

    Cation exchange resins (calcium polystyrene sulfonate, Ca-resin and sodium polystyrene sulfonate, Na-resin) have been used as agents to improve hyperkerlemia. For removing 137 Cs from the human body, the adsorption ability of the resin for 137 Cs was examined and evaluated. Resin (0.03 g) and 137 Cs (ca.1 kBq) were introduced into 3 mL of water, the Japanese Pharmacopoeia 1st fluid for a dissolution test (pH 1.2) and 2nd fluid (pH 6.8), respectively, and shaken. After 1-3 hours, the 137 Cs adsorption (%) of Na-resin was 99% in water, 60% in a pH 1.2 fluid and, 66% in a pH 6.8 fluid. By adding potassium, the 137 Cs adsorption (%) of Ca-resin was reduced. However, the 137 Cs adsorption (%) of Na-resin was almost unchanged. These results show that both resins have adsorption ability for 137 Cs in the stomach and the intestines. Therefore, the proposed method will be an effective means in the case of a radiological emergency due to 137 Cs. (author)

  18. Phenolic cation-exchange resin material for recovery of cesium and strontium. [Patent application

    Science.gov (United States)

    Ebra, M.A.; Wallace, R.M.

    1982-05-05

    A phenolic cation exchange resin with a chelating group has been prepared by reacting resorcinol with iminodiacetic acid in the presence of formaldehyde at a molar ratio of about 1:1:6. The material is highly selective for the simultaneous recovery of both cesium and strontium from aqueous alkaline solutions, such as, aqueous alkaline nuclear wate solutions. The organic resins are condensation polymers of resorcinol and formaldehyde with attached chelating groups. The column performance of the resins compares favorably with that of commercially available resins for either cesium or strontium removal. By combining Cs/sup +/ and Sr/sup 2 +/ removal in the same bed, the resins allow significant reduction of the size and complexity of facilities for processing nuclear waste.

  19. Uptake of actinides by sulphonated phosphinic acid resin from acid medium

    International Nuclear Information System (INIS)

    Jaya Mohandas; Srinivasa Rao, V.; Vijayakumar, N.; Kumar, T.; Velmurugan, S.; Narasimhan, S.V.

    2014-01-01

    The removal of uranium and americium from nitric acid solutions by sulphonated phosphinic acid resin has been investigated. The capacity of the sulphonated resin exceeds the capacities of phosphinic acid resin and commercial cation exchange resin. Other advantages of the sulphonated resin for uranium and americium removal include reduced sensitivity to acidity and inert salt concentration. (author)

  20. On the real performance of cation exchange resins in wastewater treatment under conditions of cation competition: the case of heavy metal pollution.

    Science.gov (United States)

    Prelot, Benedicte; Ayed, Imen; Marchandeau, Franck; Zajac, Jerzy

    2014-01-01

    Sorption performance of cation-exchange resins Amberlite® IRN77 and Amberlite™ IRN9652 toward Cs(I) and Sr(II) has been tested in single-component aqueous solutions and simulated waste effluents containing other monovalent (Effluent 1) or divalent (Effluent 2) metal cations, as well as nitrate, borate, or carbonate anions. The individual sorption isotherms of each main component were measured by the solution depletion method. The differential molar enthalpy changes accompanying the ion-exchange between Cs+ or Sr2+ ions and protons at the resin surface from single-component nitrate solutions were measured by isothermal titration calorimetry and they showed a higher specificity of the two resins toward cesium. Compared to the retention limits of both resins under such idealized conditions, an important depression in the maximum adsorption capacity toward each main component was observed in multication systems. The overall effect of ion exchange process appeared to be an unpredictable outcome of the individual sorption capacities of the two resins toward various cations as a function of the cation charge, size, and concentration. The cesium retention capacity of the resins was diminished to about 25% of the "ideal" value in Effluent 1 and 50% in Effluent 2; a further decrease to about 15% was observed upon concomitant strontium addition. The uptake of strontium by the resins was found to be less sensitive to the addition of other metal components: the greatest decrease in the amount adsorbed was 60% of the ideal value in the two effluents for Amberlite® IRN77 and 75% for Amberlite™ IRN9652. It was therefore demonstrated that any performance tests carried out under idealized conditions should be exploited with much caution to predict the real performance of cation exchange resins under conditions of cation competition.

  1. Lysine purification with cation exchange resin

    International Nuclear Information System (INIS)

    Khayati, GH.; Mottaghi Talab, M.; Hamooni Hagheeghat, M.; Fatemi, M.

    2003-01-01

    L-lysine is an essential amino acid for the growth most of animal species and the number one limiting amino acid for poultry. After production and biomass removal by filtration and centrifugation, the essential next step is the lysine purification and recovery. There are different methods for lysine purification. The ion exchange process is one of the most commonly used purification methods. Lysine recovery was done from broth by ion exchange resin in three different ways: repeated passing, resin soaking and the usual method. Impurities were isolated from the column by repeated wash with distilled water. Recovery and purification was done with NH 4 OH and different alcohol volumes respectively. The results showed that repeated passing is the best method for lysine absorption (maximum range 86.21 %). Washing with alkali solution revealed that most of lysine is obtained in the first step of washing. The highest degree of lysine purification was achieved with the use of 4 volumes of alcohol

  2. 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.

  3. Extraction and derivatization of chemical weapons convention relevant aminoalcohols on magnetic cation-exchange resins.

    Science.gov (United States)

    Singh, Varoon; Garg, Prabhat; Chinthakindi, Sridhar; Tak, Vijay; Dubey, Devendra Kumar

    2014-02-14

    Analysis and identification of nitrogen containing aminoalcohols is an integral part of the verification analysis of chemical weapons convention (CWC). This study was aimed to develop extraction and derivatization of aminoalcohols of CWC relevance by using magnetic dispersive solid-phase extraction (MDSPE) in combination with on-resin derivatization (ORD). For this purpose, sulfonated magnetic cation-exchange resins (SMRs) were prepared using magnetite nanoparticles as core, styrene and divinylbenzene as polymer coat and sulfonic acid as acidic cation exchanger. SMRs were successfully employed as extractant for targeted basic analytes. Adsorbed analytes were derivatized with hexamethyldisilazane (HMDS) on the surface of extractant. Derivatized (silylated) compounds were analyzed by GC-MS in SIM and full scan mode. The linearity of the method ranged from 5 to 200ngmL(-1). The LOD and LOQ ranged from 2 to 6ngmL(-1) and 5 to 19ngmL(-1) respectively. The relative standard deviation for intra-day repeatability and inter-day intermediate precision ranged from 5.1% to 6.6% and 0.2% to 7.6% respectively. Recoveries of analytes from spiked water samples from different sources varied from 28.4% to 89.3%. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Solidification of ion-exchange resins by hydrothermal hot-pressing

    International Nuclear Information System (INIS)

    Kaneko, M.

    1993-01-01

    The solidification reaction which easily occurs while continuously keeping the mixture of cation and anion exchange resins compressed under hydrothermal conditions has been demonstrated. Dehydration was considered to occur between sulphonic acid (-SO 3 H) from the cation exchange resin and quaternary ammonium [-CH 2 -N(CH 3 ) 3 OH] from anion-exchange resin-on terminal groups. The cation-and anion-exchange resins were mixed in a 1:1 weight ratio, put in a hot-pressing autoclave and compressed between pistons from the top and bottom at 600 kg cm -2 pressure. The material was continuously compressed during hydrothermal treatment at 200 kg cm -2 by a hydraulic jack and heated to a desired temperature with an induction heater. This system could be used for rapid temperature increasing up to 30 o c min -1 . The pressure and temperature were kept constant for 10 min. The autoclave was cooled to room temperature after the hydrothermal treatment. After the specimen was taken out, the ion-exchange radical reactions were estimated and the product structures were examined. The cation- and anion-exchange resin mixture was solidified. The resultant solidified body at a 300 o C reaction condition for 10 min had a 1.0 g cm -3 density and 700 kg cm -2 compressive strength, and the weight loss did not change in distilled water for 2 weeks. On the other hand, a solidification reaction did not occur at below 250 o C when only the cation or anion was solidified, but they were decomposed. These results suggest that a mixture of cation- and anion-exchange resins causes a solidification reaction under hydrothermal hot-pressing conditions at 300 o C. (author)

  5. CATION EXCHANGE METHOD FOR THE RECOVERY OF PROTACTINIUM

    Science.gov (United States)

    Studier, M.H.; Sullivan, J.C.

    1959-07-14

    A cation exchange prccess is described for separating protactinium values from thorium values whereby they are initially adsorbed together from an aqueous 0.1 to 2 N hydrochloric acid on a cation exchange resin in a column. Then selectively eluting the thorium by an ammonium sulfate solution and subsequently eluting the protactinium by an oxalate solution.

  6. 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.)

  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. Behavior of cationic, anionic and colloidal species of titanium, zirconium and thorium in presence of ion exchange resins

    International Nuclear Information System (INIS)

    Souza Filho, G. de; Abrao, A.

    1976-01-01

    The distribution of titanium, zirconium and thorium is aqueous and resin phases has been studied using strong cationic resin in the R-NH 4 form. Solutions of the above elements in perchloric, nitric, hydrochloric and suphuric media were used. Each set of experiments was made by separately varying one of the five parameters - type of anion present, acidity of solution, temperature of percolation, age of solution and concentration of the element. It was found that, depending on the particular balance of these parameters, the elements investigated may be found in acidic solutions either as cationic, anionic or colloidal species. It is emphasized that the colloidal species of titanium, zirconium or thorium are not retained by the ion exchangers, and from this property a method for the separation and purification of the above elements has been outlined [pt

  9. Separation of actinium-227 from its daughter products by cationic resins technique

    International Nuclear Information System (INIS)

    Nastasi, M.J.C.

    1976-01-01

    A method for separating actinium-227 from its daughter products based on ion exchange principle is shown. Radionuclides mixture in perchloric acid 8,5 N and chloridric acid 0,5 N medium pass by a cationic resin column. Thorium-227 and actinium-227, which are retained by the resin, are eluted with nitric acid 6 N which releases actinium-227 while oxalic acid 7% is used for thorium-227 elution [pt

  10. Experimental Characterization and Modelization of Ion Exchange Kinetics for a Carboxylic Resin in Infinite Solution Volume Conditions. Application to Monovalent-Trivalent Cations Exchange

    Energy Technology Data Exchange (ETDEWEB)

    Picart, S.; Mokhtari, H.; Jobelin, I. [CEA Marcoule, Nucl Energy Div, RadioChem and Proc Dept, Actinides Chem and Convers Lab, F-30207 Bagnols Sur Ceze (France); Ramiere, I. [Fuel Simulat Lab, Fuel Study Dept, F-13108 St Paul Les Durance (France)

    2010-07-01

    This study is devoted to the characterization of ion exchange inside a microsphere of carboxylic resin. It aims at describing the kinetics of this exchange reaction which is known to be controlled by interdiffusion in the particle. The fractional attainment of equilibrium function of time depends on the concentration of the cations in the resin which can be modelled by the Nernst-Planck equation. A powerful approach for the numerical resolution of this equation is introduced in this paper. This modeling is based on the work of Helfferich but involves an implicit numerical scheme which reduces the computational cost. Knowing the diffusion coefficients of the cations in the resin and the radius of the spherical exchanger, the kinetics can be hence completely determined. When those diffusion parameters are missing, they can be deduced by fitting experimental data of fractional attainment of equilibrium. An efficient optimization tool coupled with the implicit resolution has been developed for this purpose. A monovalent/trivalent cation exchange had been experimentally characterized for a carboxylic resin. Diffusion coefficients and concentration profiles in the resin were then deduced through this new model. (authors)

  11. Experimental Characterization and Modelization of Ion Exchange Kinetics for a Carboxylic Resin in Infinite Solution Volume Conditions. Application to Monovalent-Trivalent Cations Exchange

    International Nuclear Information System (INIS)

    Picart, S.; Mokhtari, H.; Jobelin, I.; Ramiere, I.

    2010-01-01

    This study is devoted to the characterization of ion exchange inside a microsphere of carboxylic resin. It aims at describing the kinetics of this exchange reaction which is known to be controlled by interdiffusion in the particle. The fractional attainment of equilibrium function of time depends on the concentration of the cations in the resin which can be modelled by the Nernst-Planck equation. A powerful approach for the numerical resolution of this equation is introduced in this paper. This modeling is based on the work of Helfferich but involves an implicit numerical scheme which reduces the computational cost. Knowing the diffusion coefficients of the cations in the resin and the radius of the spherical exchanger, the kinetics can be hence completely determined. When those diffusion parameters are missing, they can be deduced by fitting experimental data of fractional attainment of equilibrium. An efficient optimization tool coupled with the implicit resolution has been developed for this purpose. A monovalent/trivalent cation exchange had been experimentally characterized for a carboxylic resin. Diffusion coefficients and concentration profiles in the resin were then deduced through this new model. (authors)

  12. 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)

  13. Approach to the surface characteristics of the H+ and H+-La3+ forms of cation-exchange resins by measurement of the heat of immersion

    International Nuclear Information System (INIS)

    Suzuki, T.; Uematsu, T.

    1985-01-01

    Surface characteristics of H + and its multivalent cation-exchanged resins, which have been used as catalysts, were probed by measurement of the heats of immersion in 1-nitropropane, n-hexane, and water. It was found that the electrostatic field strengths (F) calculated from the heats of immersion in 1-nitropropane and n-hexane increased with increasing ratios of the exchanged multivalent cation (La 3+ ) in the univalent form (H + ) cation-exchange resin. This tendency was also observed in the differences in F between the La 3+ exchanged resins and H + form of the resin by using the calorimetric data obtained from the heats of immersion in water. These results suggest that the exchanged La 3 μ ion does not homogeneously interact with three univalent anionic sites (SO 3 - ) of the cation-exchange resin, but interacts with only two SO 3 - ions, that is, the La 3+ ion is localized on the surface of the resin. The difference in F obtained from the heats of immersion into water was found to be useful as a simple and rapid criterion of the surface characteristics of the cation-exchange resins. 18 references, 4 figures, 1 table

  14. Esterification of oleic acid in a three-phase, fixed-bed reactor packed with a cation exchange resin catalyst.

    Science.gov (United States)

    Son, Sung Mo; Kimura, Hiroko; Kusakabe, Katsuki

    2011-01-01

    Esterification of oleic acid was performed in a three-phase fixed-bed reactor with a cation exchange resin catalyst (Amberlyst-15) at high temperature, which was varied from 80 to 120 °C. The fatty acid methyl ester (FAME) yields in the fixed-bed reactor were increased with increases in the reaction temperature, methanol flow rate and bed height. Moreover, the FAME yields were higher than those obtained using a batch reactor due to an equilibrium shift toward the product that resulted from continuous evaporation of the produced water. In addition, there was no catalyst deactivation during the esterification of oleic acid. However, addition of sunflower oil to the oleic acid reduced the FAME yield obtained from simultaneous esterification and transesterification. The FAME yield was 97.5% at a reaction temperature of 100 °C in the fixed-bed with a height of 5 cm when the methanol and oleic acid feed rates were 8.6 and 9.0 mL/h, respectively. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Solid-phase extraction sorbent consisting of alkyltrimethylammonium surfactants immobilized onto strong cation-exchange polystyrene resin.

    Science.gov (United States)

    Reid, Kendra R; Kennedy, Lonnie J; Crick, Eric W; Conte, Eric D

    2002-10-25

    Presented is a solid-phase extraction sorbent material composed of cationic alkyltrimethylammonium surfactants attached to a strong cation-exchange resin via ion-exchange. The original hydrophilic cation-exchange resin is made hydrophobic by covering the surface with alkyl chains from the hydrophobic portion of the surfactant. The sorbent material now has a better ability to extract hydrophobic molecules from aqueous samples. The entire stationary phase (alkyltrimethylammonium surfactant) is removed along with the analyte during the elution step. The elution step requires a mild elution solvent consisting of 0.25 M Mg2+ in a 50% 2-propanol solution. The main advantage of using a removable stationary phase is that traditionally utilized toxic elution solvents such as methylene chloride, which are necessary to efficiently release strongly hydrophobic species from SPE stationary phases, may now be avoided. Also, the final extract is directly compatible with reversed-phase liquid chromatography. The performance of this procedure is presented using pyrene as a test molecule.

  16. 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

  17. Cationic mobility in polystyrene sulfone exchangers - Application to the elution of a cation on an exchange column

    International Nuclear Information System (INIS)

    Menin, Jean-Pierre

    1969-01-01

    The aim of this work is to improve elutions and separations carried out on inorganic exchangers by selective electromigration of the ionic species to be displaced. To do this, it has been found indispensable to make a fundamental study of the mobility of cations in exchangers. As the field for this research we have chosen those organic exchangers whose structure and behaviour with respect to ion-exchange are much better known that in the case of their inorganic equivalents. We have related the idea of the equivalent conductivity to that of the cation mobility in the exchanger, and this has entailed determining the specific conductivity of the exchanger and the cation concentration in the resin. The results obtained have allowed us to draw up a hypothesis concerning the cation migration mechanism in the exchanger. The third part of our work has been the application of the preceding results to an operation on an ion-exchange column, viz. the elution by an acid solution of a single fixed ion, magnesium or strontium. This work has enabled us to show that the electromigration of a cation during its elution can markedly accelerate or retard this elution. (author) [fr

  18. 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.

  19. Ontario Hydro Research Division's program for treatment of spent ion-exchange resins

    International Nuclear Information System (INIS)

    Nott, B.R.; Dodd, D.J.R.

    1981-09-01

    A brief review of the evolution of work programmes for chemical treatment of spent ion-exchange resins in Ontario Hydro's Research Division is presented. Attention has been focussed on pre-treatment processes for the treatment of the spent resins prior to encapsulation of the products in solid matrices. Spent Resin Regeneration and Acid Stripping processes were considered in some detail. Particular attention was paid to carbon-14 on spent resins, its determination in and removal from the spent resins (with the acid stripping technique). The use of separate cation and anion resin beds instead of mixed bed resins was examined with a view to reducing the volume of resin usage and consequently the volume of waste radioactive ion-exchange resin generated. (author)

  20. Conventional resin cation exchangers versus EDI for CACE measurement in power plants. Feasibility and practical field results

    Energy Technology Data Exchange (ETDEWEB)

    Sigrist, Manuel [Swan Systeme AG, Hinwil (Switzerland)

    2017-10-15

    The conductivity measurement after a cation exchanger in power plants with steam turbines was introduced soon after 1950 by Larson and Lane. Due to the simple measuring principle, the sensitivity to ionic contaminations and to its high reliability, the conductivity measurement after a cation exchanger (CACE) has become the most commonly used online analytical method in power plants with steam generators. Swan has investigated electro deionisation (EDI) as substitution of the conventional cation exchange resin and has developed a new conductivity instrument using this principle. This paper provides a description of the conventional method for cation conductivity measurements as well as of the new AMI CACE using EDI method.

  1. Conventional resin cation exchangers versus EDI for CACE measurement in power plants. Feasibility and practical field results

    International Nuclear Information System (INIS)

    Sigrist, Manuel

    2017-01-01

    The conductivity measurement after a cation exchanger in power plants with steam turbines was introduced soon after 1950 by Larson and Lane. Due to the simple measuring principle, the sensitivity to ionic contaminations and to its high reliability, the conductivity measurement after a cation exchanger (CACE) has become the most commonly used online analytical method in power plants with steam generators. Swan has investigated electro deionisation (EDI) as substitution of the conventional cation exchange resin and has developed a new conductivity instrument using this principle. This paper provides a description of the conventional method for cation conductivity measurements as well as of the new AMI CACE using EDI method.

  2. Uranium isotopic effect studies on cation and anion exchange resins

    International Nuclear Information System (INIS)

    Sarpal, S.K.; Gupta, A.R.

    1975-01-01

    Uranium isotope effects in exchange reactions involving hexavalent and tetravalent uranium, on ion exchange resins, have been re-examined. The earlier work on uranium isotope effects in electron exchange reactions involving hexavalent and tetravalent uranium, has been critically reviewed. New experimental data on these systems in hydrochloric acid medium, has been obtained, using break-through technique on anion-exchange columns. The isotope effects in these break-through experiments have been reinterpreted in a way which is consistent with the anion exchange behaviour of the various uranium species in these systems. (author)

  3. Study on the use of macroporous cation exchange resins for the separation and purification of uranium from thorium

    International Nuclear Information System (INIS)

    Rastogi, R.K.; Mahajan, M.A.; Chaudhuri, N.K.

    1992-01-01

    The possibility of using macroporous cation exchange resins for the purification of uranium from thorium relevant to the final purification of uranium after reprocessing thorium breeder fuel was explored. Two macroporous cation exchange resins were studied and compared with a commonly used gel type resin. Batch experiments and column experiments were performed to generate equilibrium data and to optimise the procedure for the separation of U from Th under process condition. Under the same condition Tulsion T-42 gave product U containing 0.1% of Th, while Amberlyst-15 gave the product U containing 1% of Th. Loading and washing rates were much higher (120 ml/hr) than those used for gel type resins (40 ml/hr). Though the volume of wash required for >90% recovery of U is more than that required with the gel type resin the disadvantage due to that is more than compensated by the use of high flow rate of loading and washing to give higher throughput. Thus there is a definite advantage of U purification with macroporous resins as compared to usual gel type resins. (author). 23 refs., 3 figs., 10 tabs

  4. Adsorption behavior of cation-exchange resin-mixed polyethersulfone-based fibrous adsorbents with bovine serum albumin

    NARCIS (Netherlands)

    Zhang, Y.; Zhang, Yuzhong; Borneman, Zandrie; Koops, G.H.; Wessling, Matthias

    2006-01-01

    The cation-exchange resin-mixed polyethersulfone (PES)-based fibrous adsorbents were developed to study their adsorption behavior with bovine serum albumin (BSA). A fibrous adsorbent with an open pore surface had much better adsorption behavior with a higher adsorbing rate. The adsorption capacity

  5. 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.)

  6. Removing and recovering of uranium from the acid mine waters by using ion exchange resin

    International Nuclear Information System (INIS)

    Nascimento, Marcos Roberto Lopes do

    1998-01-01

    Ion exchange using resins is one of the few processes capable of reducing ionic contaminants in effluents to very low levels. In this study the process was used to remove and recovery uranium from acid mine waters at Pocos de Caldas-MG Uranium Mining and Milling Plant. The local mineralogical features, allied to the biogeochemical phenomena, owing to presence of pyrite in the rock piles, moreover another factors, resulting acid drainage with several pollutants, including uranium ranging from 6 to 14 mg/l, as sulfate complex, that can be removed by anionic exchanger. The iron interference is eliminated by lime pretreatment of water, increasing pH from 2.6 to 3.3-3.8 to precipitate this cation, without changing the uranium amount. Eight anionic resins were tested, based on the uranium loading, in sorption studies. Retention time, and pH influence was verified for the exchanger chose. With breakthrough of 1 mg U/L and 10 mg U/l in the feed solution, the uranium decontamination level was 94%. Typical values of loading resin were 20-30 g U/l and 70-90 g SO 4 /l. Uranium elution was done with Na Cl solution. Retention time, saline, and acid concentration were the parameters studied. The concentrate, obtained from the eluate by ammonia precipitation, presented uranium (86,8% as U 3 O 8 ) and impurities within commercial specifications. (author)

  7. 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)

  8. Commercial Ion Exchange Resin Vitrification in Borosilicate Glass

    International Nuclear Information System (INIS)

    Cicero-Herman, C.A.; Workman, P.; Poole, K.; Erich, D.; Harden, J.

    1998-05-01

    Bench-scale studies were performed to determine the feasibility of vitrification treatment of six resins representative of those used in the commercial nuclear industry. Each resin was successfully immobilized using the same proprietary borosilicate glass formulation. Waste loadings varied from 38 to 70 g of resin/100 g of glass produced depending on the particular resin, with volume reductions of 28 percent to 68 percent. The bench-scale results were used to perform a melter demonstration with one of the resins at the Clemson Environmental Technologies Laboratory (CETL). The resin used was a weakly acidic meth acrylic cation exchange resin. The vitrification process utilized represented a approximately 64 percent volume reduction. Glass characterization, radionuclide retention, offgas analyses, and system compatibility results will be discussed in this paper

  9. Effect of blastfurnace slag addition to Portland cement for cationic exchange resins encapsulation

    Directory of Open Access Journals (Sweden)

    Stefan L.

    2013-07-01

    Full Text Available In the nuclear industry, cement-based materials are extensively used to encapsulate spent ion exchange resins (IERs before their final disposal in a repository. It is well known that the cement has to be carefully selected to prevent any deleterious expansion of the solidified waste form, but the reasons for this possible expansion are not clearly established. This work aims at filling the gap. The swelling pressure of IERs is first investigated as a function of ions exchange and ionic strength. It is shown that pressures of a few tenths of MPa can be produced by decreases in the ionic strength of the bulk solution, or by ion exchanges (2Na+ instead of Ca2+, Na+ instead of K+. Then, the chemical evolution of cationic resins initially in the Na+ form is characterized in CEM I (Portland cement and CEM III (Portland cement + blastfurnace slag cements at early age and an explanation is proposed for the better stability of CEM III material.

  10. 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

  11. 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.

  12. Development of a new generation of ion exchange resin for nuclear and fossil power plant

    International Nuclear Information System (INIS)

    Tsuzuki, Shintaro; Tagawa, Hidemi; Yamashita, Futoshi; Okamoto, Ryutaro

    2008-01-01

    It is required to maintain water quality supplied to steam generator to the water designed based on its water chemistry in order to keep the sound operation of nuclear power plants or fossil power plants. Condensate Polishing Plant (CPP) is installed for removing ions in the water which uses a mixed bed of cation exchange resin and anion exchange resin. We have developed new generation of CPP resin. The product is a unique combination of super high exchange capacity cation exchange resin and high fouling resistant anion exchange resin. The CPP resin has been used in many power plants. Amberjet 1006 was developed as a cation exchange resin with high oxidative stability, high operational capacity and New IRA900CP was developed as an anion exchange resin with high fouling resistant to leachables released out of cation exchange resin by oxidative degradation over the service period. The novel CPP resin was first used in 2000 and has now been used in many power plants in Japan. The CPP resin has been giving excellent quality of water. (author)

  13. Uranium isotope separation using styrene cation exchangers

    International Nuclear Information System (INIS)

    Kahovec, J.

    1980-01-01

    The separation of 235 U and 238 U isotopes is carried out either by simple isotope exchange in the system uranium-cation exchanger (sulphonated styrene divinylbenzene resin), or by combination of isotope exchange in a uranium-cation exchanger (Dowex 50, Amberlite IR-120) system and a chemical reaction. A review is presented of elution agents used, the degree of cation exchanger cross-linking, columns length, and 235 U enrichment. The results are described of the isotope effect study in a U(IV)-U(VI)-cation exchanger system conducted by Japanese and Romanian authors (isotope exchange kinetics, frontal analysis, reverse (indirect) frontal analysis). (H.S.)

  14. Development of a High-Throughput Ion-Exchange Resin Characterization Workflow.

    Science.gov (United States)

    Liu, Chun; Dermody, Daniel; Harris, Keith; Boomgaard, Thomas; Sweeney, Jeff; Gisch, Daryl; Goltz, Bob

    2017-06-12

    A novel high-throughout (HTR) ion-exchange (IEX) resin workflow has been developed for characterizing ion exchange equilibrium of commercial and experimental IEX resins against a range of different applications where water environment differs from site to site. Because of its much higher throughput, design of experiment (DOE) methodology can be easily applied for studying the effects of multiple factors on resin performance. Two case studies will be presented to illustrate the efficacy of the combined HTR workflow and DOE method. In case study one, a series of anion exchange resins have been screened for selective removal of NO 3 - and NO 2 - in water environments consisting of multiple other anions, varied pH, and ionic strength. The response surface model (RSM) is developed to statistically correlate the resin performance with the water composition and predict the best resin candidate. In case study two, the same HTR workflow and DOE method have been applied for screening different cation exchange resins in terms of the selective removal of Mg 2+ , Ca 2+ , and Ba 2+ from high total dissolved salt (TDS) water. A master DOE model including all of the cation exchange resins is created to predict divalent cation removal by different IEX resins under specific conditions, from which the best resin candidates can be identified. The successful adoption of HTR workflow and DOE method for studying the ion exchange of IEX resins can significantly reduce the resources and time to address industry and application needs.

  15. Comparative study of the ionic exchange of Ca++, Sr++, and Ba++ cations on resins and inorganic exchangers

    International Nuclear Information System (INIS)

    Sanchez Batanero, P.

    1969-03-01

    With a view to applying the results to certain problems related to chemical separations in activation analysis, a study has been made, of the possibilities of separating the alkaline-earth elements Ca, Sr and Ba on organic resins and inorganic exchangers using the radioactive indicator method. The partition coefficients of the cations Ca 2+ , Sr 2+ and Ba 2+ have been measured on Dowex 50 W (NH 4 + ) x 8 resin in the presence of EDTA - NTA - EGTA and DCTA as complexing agents, and on zirconium phosphate, tungstate and molybdate in the presence of HCl and NH 4 Cl. Methods have been developed for separating mixtures of alkaline-earth elements using DCTA-NH 4 + followed by elution on Dowex 50 W (NH 4 + ) x 8 resin columns and on zirconium phosphate. Amongst the complexing agents used on the ion-exchange resins the most promising appears to be DCTA which leads to partition coefficients Ca, Sr and Ba which are very different. The results of measurements of partition coefficients on zirconium phosphate (NH 4 + form) using DCTA-NH 4 + show the interesting possibilities of separations on columns. The separation of the alkaline-earth elements on zirconium phosphate seems to be less quantitative than on Dowex 50 resin; it is however much faster in the former case and this can be useful for treating short half-life radioisotopes in activation analysis. (author) [fr

  16. U3O8 powder from uranyl-loaded cation exchange resin

    International Nuclear Information System (INIS)

    Mosley, W.C.

    1985-01-01

    Large batches of U 3 O 8 , suitable for powder metallurgy fabrication of Al-U 3 O 8 cores for reactor fuel tubes, have been produced by deep-bed calcination of granular uranyl-loaded macroporous sulfonate cation exchange resin at 900 to 950 0 C in air. Deep-bed calcination is the backup process for the reference process of rotary calcination and sintering. These processes are to be used for recycling uranium, and to produce U 3 O 8 in the Fuel Production Facility to be built at the Savannah River Plant. 2 refs., 6 figs

  17. Electrodeposition properties of modified cational epoxy resin-type photoresist

    International Nuclear Information System (INIS)

    Yong He; Yunlong Zhang; Feipeng Wu; Miaozhen Li; Erjian Wang

    1999-01-01

    Multi-component cationic epoxy and acrylic resin system for ED photoresist was used in this work, since they can provide better storage stability for ED emulsion and better physical and chemical properties of deposited film than one-component system. The cationic main resin (AE) was prepared from amine modified epoxy resins and then treated with acetic acid. The amination degree was controlled as required. The synthetic procedure of cationic main resins is described in scheme I. The ED photoresist (AME) is composed of cationic main resin (AE) and nonionic multifunctional acrylic crosslinkers (PETA), in combination with suitable photo-initiator. They can easily be dispersed in deionized water to form a stable ED emulsion. The exposed part of deposited film upon UV irradiation occurs crosslinking to produce an insoluble semi-penetrating network and the unexposed part remains good solubility in the acidic water solution. It is readily utilized for fabrication of fine micropattern. The electrodeposition are carried out on Cu plate at room temperature. To evaluate the electrodeposition properties of ED photoresist (AME), the different influences are examined

  18. Ion chromatography for the analysis of salt splitting capacities of cation and anion resin in premixed resin sample

    International Nuclear Information System (INIS)

    Ghosh, Satinath; Kumar, Rakesh; Tripathy, M.K.; Dhole, K.; Sharma, R.S.; Varde, P.V.

    2017-01-01

    Mixed bed ion exchange resin is commonly used in various plants including nuclear reactors for the purpose of fine polishing. The analysis of ion exchange capacities of cation and anion resin in resin mixture is therefore an agenda in the context of purchasing of premixed resin from the manufacturer. An ion chromatographic method for assaying ion exchange capacities of pure as well as mixed resin has been optimized. The proposed method in contrast to the conventional ASTM method has been found to be quite encouraging to consider it as an alternate method for the analysis of premixed resin. (author)

  19. Capability of cation exchange technology to remove proven N-nitrosodimethylamine precursors.

    Science.gov (United States)

    Li, Shixiang; Zhang, Xulan; Bei, Er; Yue, Huihui; Lin, Pengfei; Wang, Jun; Zhang, Xiaojian; Chen, Chao

    2017-08-01

    N-nitrosodimethylamine (NDMA) precursors consist of a positively charged dimethylamine group and a non-polar moiety, which inspired us to develop a targeted cation exchange technology to remove NDMA precursors. In this study, we tested the removal of two representative NDMA precursors, dimethylamine (DMA) and ranitidine (RNTD), by strong acidic cation exchange resin. The results showed that pH greatly affected the exchange efficiency, with high removal (DMA>78% and RNTD>94%) observed at pHMg 2+ >RNTD + >K + >DMA + >NH 4 + >Na + . The partition coefficient of DMA + to Na + was 1.41±0.26, while that of RNTD + to Na + was 12.1±1.9. The pseudo second-order equation fitted the cation exchange kinetics well. Bivalent inorganic cations such as Ca 2+ were found to have a notable effect on NA precursor removal in softening column test. Besides DMA and RNTD, cation exchange process also worked well for removing other 7 model NDMA precursors. Overall, NDMA precursor removal can be an added benefit of making use of cation exchange water softening processes. Copyright © 2017. Published by Elsevier B.V.

  20. 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.)

  1. Sorption of Pu(IV) from nitric acid by bifunctional anion-exchange resins

    International Nuclear Information System (INIS)

    Bartsch, R.A.; Zhang, Z.Y.; Elshani, S.; Zhao, W.; Jarvinen, G.D.; Barr, M.E.; Marsh, S.F.; Chamberlin, R.M.

    1999-01-01

    Anion exchange is attractive for separating plutonium because the Pu(IV) nitrate complex is very strongly sorbed and few other metal ions form competing anionic nitrate complexes. The major disadvantage of this process has been the unusually slow rate at which the Pu(IV) nitrate complex is sorbed by the resin. The paper summarizes the concept of bifunctional anion-exchange resins, proposed mechanism for Pu(IV) sorption, synthesis of the alkylating agent, calculation of K d values from Pu(IV) sorption results, and conclusions from the study of Pu(IV) sorption from 7M nitric acid by macroporous anion-exchange resins including level of crosslinking, level of alkylation, length of spacer, and bifunctional vs. monofunctional anion-exchange resins

  2. New system applying image processor to automatically separate cation exchange resin and anion exchange resin for condensate demineralizer

    International Nuclear Information System (INIS)

    Adachi, Tsuneyasu; Nagao, Nobuaki; Yoshimori, Yasuhide; Inoue, Takashi; Yoda, Shuji

    2014-01-01

    In PWR plant, condensate demineralizer is equipped to remove corrosive ion in condensate water. Mixed bed packing cation exchange resin (CER) and anion exchange resin (AER) is generally applied, and these are regenerated after separation to each layer periodically. Since the AER particle is slightly lighter than the CER particle, the AER layer is brought up onto the CER layer by feeding water upward from the bottom of column (backwashing). The separation performance is affected by flow rate and temperature of water for backwashing, so normally operators set the proper condition parameters regarding separation manually every time for regeneration. The authors have developed the new separation system applying CCD camera and image processor. The system is comprised of CCD camera, LED lamp, image processor, controller, flow control valves and background color panel. Blue color of the panel, which is corresponding to the complementary color against both ivory color of AER and brown color of CER, is key to secure the system precision. At first the color image of the CER via the CCD camera is digitized and memorized by the image processor. The color of CER in the field of vision of the camera is scanned by the image processor, and the position where the maximum difference of digitized color index is indicated is judged as the interface. The detected interface is able to make the accordance with the set point by adjusting the flow rate of backwashing. By adopting the blue background panel, it is also possible to draw the AER out of the column since detecting the interface of the CER clearly. The system has provided the reduction of instability factor concerning separation of resin during regeneration process. The system has been adopted in two PWR plants in Japan, it has been demonstrating its stable and precise performance. (author)

  3. Exploration of overloaded cation exchange chromatography for monoclonal antibody purification.

    Science.gov (United States)

    Liu, Hui F; McCooey, Beth; Duarte, Tiago; Myers, Deanna E; Hudson, Terry; Amanullah, Ashraf; van Reis, Robert; Kelley, Brian D

    2011-09-28

    Cation exchange chromatography using conventional resins, having either diffusive or perfusive flow paths, operated in bind-elute mode has been commonly employed in monoclonal antibody (MAb) purification processes. In this study, the performance of diffusive and perfusive cation exchange resins (SP-Sepharose FF (SPSFF) and Poros 50HS) and a convective cation exchange membrane (Mustang S) and monolith (SO(3) Monolith) were compared. All matrices were utilized in an isocratic state under typical binding conditions with an antibody load of up to 1000 g/L of chromatographic matrix. The dynamic binding capacity of the cation exchange resins is typically below 100 g/L resin, so they were loaded beyond the point of anticipated MAb break through. All of the matrices performed similarly in that they effectively retained host cell protein and DNA during the loading and wash steps, while antibody flowed through each matrix after its dynamic binding capacity was reached. The matrices differed, though, in that conventional diffusive and perfusive chromatographic resins (SPSFF and Poros 50HS) demonstrated a higher binding capacity for high molecular weight species (HMW) than convective flow matrices (membrane and monolith); Poros 50HS displayed the highest HMW binding capacity. Further exploration of the conventional chromatographic resins in an isocratic overloaded mode demonstrated that the impurity binding capacity was well maintained on Poros 50HS, but not on SPSFF, when the operating flow rate was as high as 36 column volumes per hour. Host cell protein and HMW removal by Poros 50HS was affected by altering the loading conductivity. A higher percentage of host cell protein removal was achieved at a low conductivity of 3 mS/cm. HMW binding capacity was optimized at 5 mS/cm. Our data from runs on Poros 50HS resin also showed that leached protein A and cell culture additive such as gentamicin were able to be removed under the isocratic overloaded condition. Lastly, a MAb

  4. Adsorption Equilibrium Equation of Carboxylic Acids on Anion-Exchange Resins in Water.

    Science.gov (United States)

    Kanazawa, Nobuhiro; Urano, Kohei; Kokado, Naohiro; Urushigawa, Yoshikuni

    2001-06-01

    The adsorption of propionic acid and benzoic acid on anion-exchange resins was analyzed, and an adsorption equilibrium equation of carboxylic acids was proposed. The adsorption of carboxylic acids on the anion-exchange resins was considered to be the sum of the physical adsorption of the molecule and the ion-exchange adsorption of the ion, which were independent of each other. For the physical adsorption of carboxylic acids, it was conformed to the Freundlich equation. For the ion-exchange adsorption of carboxylate ions, the equilibrium equation corresponded well with the experimental results for wide ranges of concentration and pH. The equation contains a selectivity coefficient S(A)(Cl) for the chloride ion versus the carboxylate ion, which was considered essentially a constant. The influent of the bicarbonate ion from carbon dioxide in air could also be expressed by the additional equilibrium equation with the selectivity coefficient S(HCO(3))(Cl) for the chloride ion versus the bicarbonate ion. Consequently, an adsorption equilibrium equation can estimate the equilibrium adsorption amounts. Even the effect of a coexisting bicarbonate ion is inconsequential when the parameters of the Freundlich isotherm equation and the selectivity coefficients of the carboxylate ion and the bicarbonate ion in each resin are determined in advance. Copyright 2001 Academic Press.

  5. 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)

  6. 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)

  7. 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)

  8. Studies on radiation damage to polystyrene exchanger in different cationic forms

    International Nuclear Information System (INIS)

    Dedgaonkar, V.G.; Jagtap, N.B.; Waghmare, S.; Kulkarni, S.A.

    1985-01-01

    Polystyrene divinylbenzene copolymer containing nuclear sulfonic acid functional group and H + , Sr 2+ , Cu 2+ , UO 2 2+ or Al 3+ exchangeable cation was subjected to varying gamma doses to study the effects on its physicochemical properties. The exchange capacity and moisture content decreased, the maximum effect was in the case of Cu ++ form of the resin. The data are explained on the basis of metal oxygen bonding. IR spectra indicated the formation of new exchange sites upon irradiation and disapearance of the original functional groups. (author)

  9. 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

  10. 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)

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

    International Nuclear Information System (INIS)

    Otte, J.N.A.; Liebmann, D.

    1989-01-01

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

  12. Ion-exchange Resin Catalyzed Esterification of Lactic Acid with Isopropanol: a Kinetic Study

    Directory of Open Access Journals (Sweden)

    Amrit P. Toor

    2011-05-01

    Full Text Available The kinetic behavior of esterification of lactic acid with isopropanol over an acidic cation exchange resin, Amberlyst 15, was studied under isothermal condition. Isopropyl lactate synthesized in this reaction is an important pharmaceutical intermediate. The experiments were carried out in a stirred batch reactor in the temperature range of 323.15 to 353.15 K. The effect of various parameters such as temperature, molar ratio and catalyst loading was studied. Variation in parameters on rate of reaction demonstrated that the reaction was intrinsically controlled. Kinetic modeling was performed using Eley-Rideal model which acceptably fits the experimental data. The activation energy was found to be 22.007 kJ/mol and frequency factor was 0.036809 l2 g-1 mol-1 min-1 for forward reaction. The value of entropy for the forward reaction was found to be 182.317 J K-1 mol-1 . © 2011 BCREC UNDIP. All rights reserved(Received: 19th January 2011, Revised: 16th March 2011; Accepted: 16th March 2011[How to Cite: A.P. Toor, M. Sharma, S. Thakur, and R. K. Wanchoo. (2011. Ion-exchange Resin Catalyzed Esterification of Lactic Acid with Isopropanol: a Kinetic Study. Bulletin of Chemical Reaction Engineering and Catalysis, 6(1: 39-45. doi:10.9767/bcrec.6.1.791.39-45][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.6.1.791.39-45 || or local:  http://ejournal.undip.ac.id/index.php/bcrec/article/view/791 ] | View in  

  13. Oxidative degradation of ion-exchange resins in acid medium. Vol. 3

    International Nuclear Information System (INIS)

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

    1996-01-01

    Volume reduction of spent ion-exchange resins used in nuclear facilities receive increasing importance due to the increase in storage cost, unstable physical and chemical properties and their relatively high specific activity (in some cases up to 1 Ci per liter). The present study is part of research program on the treatment and immobilization of radioactive spent ion-exchange resins simulate; hydrogen peroxide was used for the oxidative degradation of spent ion-exchange resins simulate in sulphuric acid medium. Five liters ring digester developed in Karlsruhe nuclear research center-(KFK)- in germany was the chosen option to perform the oxidation process. The work reported focused on the kinetics and mechanism of the oxidation process. Heating the organic resins in sulphuric acid results in its carbonization and partial oxidation of only 1.7% of the carbon added. Results show that the oxidation reaction is a relatively slow process of first order with K value in the order of 10 -4 min -1 , and the main oxidation product was carbon dioxide. The production of carbon oxide in the off gas stream increased sharply by the addition of hydrogen peroxide to the hot sulphuric acid-resin mixture. The results obtained show that more than 97% of the carbon added was oxidized to carbon dioxide and carbon monoxide. The rate constant value (K) of this reaction was calculated to be (1.69±0.13) x 10 -2 min -1 . The results of gas chromatographic analysis indicate that no significant amounts of hazardous organic materials were detected in the off-gas streams. 6 figs., 4 tabs

  14. 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 ...

  15. Cation exchange assisted binding-elution strategy for enzymatic synthesis of human milk oligosaccharides (HMOs).

    Science.gov (United States)

    Zhu, Hailiang; Wu, Zhigang; Gadi, Madhusudhan Reddy; Wang, Shuaishuai; Guo, Yuxi; Edmunds, Garrett; Guan, Wanyi; Fang, Junqiang

    2017-09-15

    A cation exchange assisted binding-elution (BE) strategy for enzymatic synthesis of human milk oligosaccharides (HMOs) was developed. An amino linker was used to provide the cation ion under acidic condition which can be readily bound to cation exchange resin and then eluted off by saturated ammonium bicarbonate. Ammonium bicarbonate in the collections was easily removed by vacuum evaporation. This strategy circumvented the incompatible issue between glycosyltransferases and solid support or large polymers, and no purification was needed for intermediate products. With current approach, polyLacNAc backbones of HMOs and fucosylated HMOs were synthesized smoothly. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Synthesis and characterization of carboxylic cation exchange bio-resin for heavy metal remediation.

    Science.gov (United States)

    Kulkarni, Vihangraj V; Golder, Animes Kumar; Ghosh, Pranab Kumar

    2018-01-05

    A new carboxylic bio-resin was synthesized from raw arecanut husk through mercerization and ethylenediaminetetraacetic dianhydride (EDTAD) carboxylation. The synthesized bio-resin was characterized using thermogravimetric analysis, field emission scanning electron microscopy, proximate & ultimate analyses, mass percent gain/loss, potentiometric titrations, and Fourier transform infrared spectroscopy. Mercerization extracted lignin from the vesicles on the husk and EDTAD was ridged in to, through an acylation reaction in dimethylformamide media. The reaction induced carboxylic groups as high as 0.735mM/g and a cation exchange capacity of 2.01meq/g functionalized mercerized husk (FMH). Potentiometric titration data were fitted to a newly developed single-site proton adsorption model (PAM) that gave pKa of 3.29 and carboxylic groups concentration of 0.741mM/g. FMH showed 99% efficiency in Pb(II) removal from synthetic wastewater (initial concentration 0.157mM), for which the Pb(II) binding constant was 1.73×10 3 L/mol as estimated from modified PAM. The exhaustion capacity was estimated to be 18.7mg/g of FMH. Desorption efficiency of Pb(II) from exhausted FMH was found to be about 97% with 0.1N HCl. The FMH simultaneously removed lead and cadmium below detection limit from a real lead acid battery wastewater along with the removal of Fe, Mg, Ni, and Co. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Computer simulation of displacement cation exchange chromatography: separation of trivalent actinides and lanthanides

    International Nuclear Information System (INIS)

    Forsberg, C.W.

    1980-05-01

    A first-generation mathematical model of displacement cation exchange chromatography (CES) was constructed. The model incorporated the following phenomena: diffusion of cations up and down the column, diffusion of cations from the bulk liquid to the resin surface, and equilibrium of cations between liquid and solid resin beads. A limited number of experiments with rare earths using DTPA as the separation agent were undertaken to increase the current understanding of the processes involved in cation exchange chromatography. The numerical computer program based on the mathematical model was written in FORTRAN IV for use on the IBM 360 series of computers

  18. Destruction of gel sulfonated cation-exchangers of the KU-2 type under the influence of hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Roginskaya, B.S.; Zavadovskaya, A.S.; Znamenskii, Yu.P.; Paskhina, N.A.; Dobrova, E.I.

    1988-10-20

    The purpose of this work was to study the mechanism of interaction of Soviet sulfonated cation-exchangers of the KU-2 type with hydrogen peroxide. It is shown that under the influence of hydrogen peroxide sulfonated cation-exchangers begin, after a certain induction period, to lose capacity and to release destruction products into water; the length of the induction period increases with the degree of cross-linking. In a given time of contact between the resin and the solution the degree of destruction falls with increase of cross-linking. The principal product of destruction of sulfonated cation-exchangers is an aromatic sulfonic acid containing oxidized groups in the side chains.

  19. Cation exchange resins labeled with holmium-166 for treatment of liver malignancy

    International Nuclear Information System (INIS)

    Costa, Renata F.; Osso Junior, Joao A.

    2008-01-01

    The increasing interest in new therapeutic radiopharmaceuticals is prompting investigators to utilize isotopes with more focused capabilities for treating various tumors, reducing the negative effects on neighboring healthy cells. Local radionuclide therapy using radioactive microspheres is a promising therapy for non-operable group of patients suffering from liver malignancies. Many publications have shown the success of this technique. The emphasis in the present work is the resin-based microspheres labeled with 166 Ho. The production of 166 Ho is feasible in the IEA-R1 Reactor at IPEN-CNEN/SP, because it does not need high power and high neutron fluxes. Samples of Ho 2 O 3 were irradiated in selected positions of the nuclear reactor IEA-R1 at IPEN/CNEN-SP. The neutron flux was 1.0 x10 13 n.s -1 .cm -2 for 1 hour. The dissolution of Ho 2 O 3 was studied with different volumes of 0.1M HCl and also varying the heating temperature. The AG50W-X8 200-400 mesh and CM Sephadex C-25 cation exchange resins were labeled with 166 Ho. The retention of 166 Ho in the resins was studied and also its stability. The results of the dissolution experiments of Ho 2 O 3 showed that there is a direct relation between the increasing volumes needed to dissolve higher masses, and also the positive effect of raising the temperature. The results show very good retention of 166 Ho in both columns, even when high volumes of 0.1M HCl are passed through the column containing the resins and its good stability towards saline solution, PBS solution and glucose.Although the resins employed in this work did not have the right particle size (20-50μm), the chemical behavior showed the very good labeling of the resins with 166 Ho, and its stability. (author)

  20. Uranium extraction from sulfuric acid solution using anion exchange resin

    International Nuclear Information System (INIS)

    Sheta, M. E.; Abdel Aal, M. M.; Kandil, A. T.

    2012-12-01

    Uranium is currently recovered from sulfuric acid leach liquor using anion exchange resin as Amberlite IRA 402 (CT). This technology is based on fact that, uranium exists as anionic complexes. This takes place by controlling the pH of the solution, agitation time, temperature and resin to solution ratio (R/S). In this work, batch stirrer tank used for uranium extraction from sulfate medium and after extraction, elution process was done using 1M NaCl solution. After extraction and elution process, the resin was separated from the system and uranium was determined in the solution. (Author)

  1. Kinetics of transesterification of methyl acetate and n-octanol catalyzed by cation exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yong; Gao, Li; Li, Xiying; Mao, Liqun [Henan University, Kaifeng (China); Wei, Min [Henan University of Technology, Zhengzhou (China)

    2013-05-15

    The transesterification kinetics of methyl acetate with n-octanol to octyl acetate and methanol were studied using Amberlyst 15 as catalyst in a batch stirred reactor. The influence of the agitation speed, particle size, temperature, catalyst loading, and initial reactants molar ratio was investigated in detail. A pseudo-homogeneous (PH) kinetic model was applied to correlate the experimental data in the temperature range of 313.15 K to 328.15 K. The estimated kinetic parameters made the calculated results in good agreement with the experimental data. A kinetic model describing the transesterification reaction catalyzed by cation exchange resins was developed.

  2. Preparation of minor actinides targets or blankets by the means of Ionic Exchange Resin

    Energy Technology Data Exchange (ETDEWEB)

    Picart, S.; Mokhtari, H.; Ramiere, I.; Jobelin, I. [CEA, Nuclear Energy Division, RadioChemistry and Process Department, Actinides Chemistry Laboratory, BP17171, Bagnols-sur-Ceze, 30207 (France)

    2009-06-15

    The objective of our R and D work is the elaboration by the use of ionic exchange resin of minor actinide precursors for target or blanket dedicated to their transmutation in sodium fast reactor. From the beginning, the resin process called WAR (acronym of Weak Acid Resin) was developed in the 70's at the ORNL for the making of uranium carbide kernels for the high temperature gas reactor [1] [2]. By now, our aim is to extend this concept to the manufacturing of minor actinides oxide mixed with uranium oxides [3]. More precisely, this process can be divided in two major steps: the loading of the resin and the thermal treatment of the fully loaded resin driving either to oxide or carbide phases depending on the gas atmosphere. The difficulty stems from the preparation of the loading solutions which must fulfill precise conditions of pH in presence of actinides cations prone to hydrolysis. Furthermore, the proportions of uranium and minor actinides in solutions must be adjusted to fit the right ratio in the solid. The study presented here will then focus on the experiments and tests which enable us to optimize the fixing of minor actinides on ionic exchange resin and their carbonization in oxide. [1] G. W. Weber, R. L. Beatty et V. J. Tennery, Nuclear Technology, 35, 217-226, (1977), 'Processing and composition control of weak-acid-resin derived fuel microspheres'. [2] K. J. Notz, P. A. Haas, J. H. Shaffer, Radiochimica Acta, 25, 153-160, (1978). 'The preparation of HTGR Fissile Fuel Kernels by Uranium Loading of Ion Exchange Resin'. [3] S. Picart, H. Mokhtari, I. Ramiere, 'Plutonium Futures, The Science 2008', 7-11 july 2008, Dijon, France. 'Modelling of the ionic Exchange between a weak acid resin in its ammonium form and a minor actinide'. (authors)

  3. Effect of pore structure on the removal of clofibric acid by magnetic anion exchange resin.

    Science.gov (United States)

    Tan, Liang; Shuang, Chendong; Wang, Yunshu; Wang, Jun; Su, Yihong; Li, Aimin

    2018-01-01

    The effect of pore structure of resin on clofibric acid (CA) adsorption behavior was investigated by using magnetic anion exchange resins (ND-1, ND-2, ND-3) with increasing pore diameter by 11.68, 15.37, 24.94 nm. Resin with larger pores showed faster adsorption rates and a higher adsorption capacity because the more opened tunnels provided by larger pores benefit the CA diffusion into the resin matrix. The ion exchange by the electrostatic interactions between Cl-type resin and CA resulted in chloride releasing to the solution, and the ratio of released chloride to CA adsorption amount decreased from 0.90 to 0.65 for ND-1, ND-2 and ND-3, indicating that non-electrostatic interactions obtain a larger proportional part of the adsorption into the pores. Co-existing inorganic anions and organic acids reduced the CA adsorption amounts by the competition effect of electrostatic interaction, whereas resins with more opened pore structures weakened the negative influence on CA adsorption because of the existence of non-electrostatic interactions. 85.2% and 65.1% adsorption amounts decrease are calculated for resin ND-1 and ND-3 by the negative influence of 1 mmol L -1 NaCl. This weaken effect of organic acid is generally depends on its hydrophobicity (Log Kow) for carboxylic acid and its ionization degree (pKb) for sulfonic acid. The resins could be reused with the slightly decreases by 1.9%, 3.2% and 5.4% after 7 cycles of regeneration, respectively for ND-1, ND-2 and ND-3, suggesting the ion exchange resin with larger pores are against its reuse by the brine solution regeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Purification of gamma-amino butyric acid (GABA) from fermentation of defatted rice bran extract by using ion exchange resin

    Science.gov (United States)

    Tuan Nha, Vi; Phung, Le Thi Kim; Dat, Lai Quoc

    2017-09-01

    Rice bran is one of the significant byproducts of rice processing with 10 %w/w of constitution of whole rice grain. It is rich in nutrient compounds, including glutamic acid. Thus, it could be utilized for the fermentation with Lactobateria for synthesis of GABA, a valuable bioactive for antihypertensive effects. However, the concentration and purity of GABA in fermentation broth of defatted rice bran extract is low for production of GABA drug. This research focused on the purification of GABA from the fermentation broth of defatted rice bran extract by using cation exchange resin. The results indicate that, the adsorption isotherm of GABA by Purelite C100 showed the good agreement with Freundlich model, with high adsorption capacity. The effects of pH and concentration of NaCl in eluent on the elution were also investigated. The obtained results show that, at the operating conditions of elution as follows: pH 6.5, 0.8 M of NaCl in eluent, 0.43 of bed volume; concentration of GABA in accumulative eluent, the purity and recovery yield of GABA were 743.8 ppm, 44.0% and 84.2%, respectively. Results imply that, it is feasible to apply cation exchange resin for purification of GABA from fermentation broth of defatted rice bran extract.

  5. Kinetic Study of Esterification of Acetic Acid with n-butanol and isobutanol Catalyzed by Ion Exchange Resin

    Directory of Open Access Journals (Sweden)

    Amrit Pal Toor

    2011-05-01

    Full Text Available Esters are an important pharmaceutical intermediates and very useful perfumery agents. In this study the esterification of acetic acid with n-butanol and iso-butanol over an acidic cation exchange resin, Amberlyst 15 were carried out. The effects of certain parameters such as temperature, catalyst loading, initial molar ratio between reactants on the rate of reaction were studied. The experiments were conducted in a stirred batch reactor in the temperature range of 351.15 K to 366.15K.Variation of parameters on rate of reaction demonstrated that the reaction was intrinsically controlled.The activation energy for the esterification of acetic acid with n-butanol and iso butanol is found to be 28.45 k J/mol and 23.29 kJ/mol respectively. ©2011 BCREC UNDIP. All rights reserved.(Received: 16th December 2010, Revised: 19th March 2011; Accepted: 7th April 2011[How to Cite: A.P. Toor, M. Sharma, G. Kumar, and R. K. Wanchoo. (2011. Kinetic Study of Esterification of Acetic Acid with n-butanol and isobutanol Catalyzed by Ion Exchange Resin. Bulletin of Chemical Reaction Engineering and Catalysis, 6(1: 23-30. doi:10.9767/bcrec.6.1.665.23-30][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.6.1.665.23-30 || or local: http://ejournal.undip.ac.id/index.php/bcrec/article/view/665 ] | View in 

  6. Magnesium isotope fractionation in cation-exchange chromatography

    International Nuclear Information System (INIS)

    Oi, T.; Yanase, S.; Kakihana, H.

    1987-01-01

    Band displacement chromatography of magnesium has been carried out successfully for the purpose of magnesium isotope separation by using a strongly acidic cation-exchange resin and the strontium ion as the replacement ion. A small but definite accumulation of the heavier isotopes ( 25 Mg, 26 Mg) has been observed at the front parts of the magnesium chromatograms. The heavier isotopes have been fractionated preferentially into the solution phase. The single-stage separation factors have been calculated for the 25 Mg/ 24 Mg and 26 Mg/ 24 isotopic pairs at 25 0 C. The reduced partition function ratios of magnesium species involved in the present study have been estimated

  7. Cation exchange properties of zeolites in hyper alkaline aqueous media.

    Science.gov (United States)

    Van Tendeloo, Leen; de Blochouse, Benny; Dom, Dirk; Vancluysen, Jacqueline; Snellings, Ruben; Martens, Johan A; Kirschhock, Christine E A; Maes, André; Breynaert, Eric

    2015-02-03

    Construction of multibarrier concrete based waste disposal sites and management of alkaline mine drainage water requires cation exchangers combining excellent sorption properties with a high stability and predictable performance in hyper alkaline media. Though highly selective organic cation exchange resins have been developed for most pollutants, they can serve as a growth medium for bacterial proliferation, impairing their long-term stability and introducing unpredictable parameters into the evolution of the system. Zeolites represent a family of inorganic cation exchangers, which naturally occur in hyper alkaline conditions and cannot serve as an electron donor or carbon source for microbial proliferation. Despite their successful application as industrial cation exchangers under near neutral conditions, their performance in hyper alkaline, saline water remains highly undocumented. Using Cs(+) as a benchmark element, this study aims to assess the long-term cation exchange performance of zeolites in concrete derived aqueous solutions. Comparison of their exchange properties in alkaline media with data obtained in near neutral solutions demonstrated that the cation exchange selectivity remains unaffected by the increased hydroxyl concentration; the cation exchange capacity did however show an unexpected increase in hyper alkaline media.

  8. ADSORPTION METHOD FOR SEPARATING METAL CATIONS

    Science.gov (United States)

    Khym, J.X.

    1959-03-10

    The chromatographic separation of fission product cations is discussed. By use of this method a mixture of metal cations containing Zr, Cb, Ce, Y, Ba, and Sr may be separated from one another. Mentioned as preferred exchange adsorbents are resins containing free sulfonic acid groups. Various eluants, such as tartaric acid, HCl, and citric acid, used at various acidities, are employed to effect the selective elution and separation of the various fission product cations.

  9. Treatment of radioactive ionic exchange resins by super- and sub-critical water oxidation (SCWO)

    International Nuclear Information System (INIS)

    Kim, Kyeongsook; Son, Soon Hwan; Kim, Kwang Sin; Han, Joo Hee; Han, Kee Do; Do, Seung Hoe

    2010-01-01

    As the usage of ion exchange resins increases the inventory of spent ion exchange resins increases in nuclear power plants. This study is to find an environmental-friendly process to treat theses spent resins. The test samples were prepared by diluting the slurry made by wet ball milling the spent cationic exchange resins for 24 h. The spent cationic exchange resins were separated from mixed ion exchange resins by a fluidized bed gravimetric separator. The decomposition of the samples was investigated with super-critical water oxidation (SCWO) equipment. A statistical test method - the central composite design as a statistical design of experiments - was adopted to find the optimum condition to decompose the spent exchange resins. The optimum condition was 60% of excess oxygen, 22.5 min of residence time, 0.615 wt% of NaOH, 358 of reaction temperature, and 3600 psi of reaction pressure, which is a sub-critical condition. The liquid product of the decomposition has the characteristics of 80-185 ppm of COD (Chemical Oxygen Demand), 4.0-6.0 of pH, and <1.0 ppm of corrosive components (Ni, Fe, Cr, and Mo). The exhaust gas from the SCWO equipment contained NOx of 0 ppm, SOx of 3 ppm (environment exhaust standard in Korea: NOx 200 ppm, SOx 300 ppm). Co-substituted mock samples were prepared to simulate spent cationic exchange resins from nuclear power plants which can contain radioactive Co isotopes. The conditions to obtain organic compound destruction ratio which conforms the effluent stand for the mock samples were found. The treated water filtered with 0.2-filter contained less than 1 ppm of Co. Thus Co recovery rate of more 99% was achieved.

  10. Solid phase extraction of copper(II) by fixed bed procedure on cation exchange complexing resins.

    Science.gov (United States)

    Pesavento, Maria; Sturini, Michela; D'Agostino, Girolamo; Biesuz, Raffaela

    2010-02-19

    The efficiency of the metal ion recovery by solid phase extraction (SPE) in complexing resins columns is predicted by a simple model based on two parameters reflecting the sorption equilibria and kinetics of the metal ion on the considered resin. The parameter related to the adsorption equilibria was evaluated by the Gibbs-Donnan model, and that related to the kinetics by assuming that the ion exchange is the adsorption rate determining step. The predicted parameters make it possible to evaluate the breakthrough volume of the considered metal ion, Cu(II), from different kinds of complexing resins, and at different conditions, such as acidity and ionic composition. Copyright 2009. Published by Elsevier B.V.

  11. Electrochemical ion exchanger in the water circuit to measure cation conductivity

    International Nuclear Information System (INIS)

    Bengtsson, B.; Ingemarsson, R.; Settervik, G.; Velin, A.

    2010-01-01

    In Ringhals NPP, more than four years of successful operation with a full-scale EDI for the recycling of steam generator blow down (SGBD) gave the inspiration to modify and 'scale down' this EDI process. This with purpose to explore the possibilities to replace the cation exchanger columns used for cation conductivity analysis, with some small and integrated electrochemical ion-exchange cells. Monitoring the cation conductivity requires the use of a small cation resin column upstream of the conductivity probe and is one of the most important analyses at power plants. However, when operating with high alkaline treatment in the steam circuit, it's connected to the disadvantage of getting the resins rapidly exhausted, with needs to be frequently replaced or regenerated. This is causing interruptions in the monitoring and giving rise to high workload for the maintenance. This paper reports about some optimization and tests of two different two-compartment electrochemical cells for the possible replacements of cation resin columns when analyzing cation conductivity in the secondary steam circuit at Ringhals NPPs. Field tests during start up condition and more than four months of steady operation together with real and simulated test for impurity influences, indicates that a ELectrical Ion Echange process (ELIX) could be successfully used to replace the resin columns in Ringhals during operating with high pH-AVT (All Volatile Treatment), using hydrazine and ammonia. Installation of an ELIX-system downstream a particle filter and upstream of a small cation resin column, will introduce additional safety and further reduce the maintenance with possible interruptions. Performance of the ELIX-process together with other chemical additives (Morpholine, ETA, MPA, DMA) and dispersants, may be further evaluated to qualify the ELIX-process as well as SGBD-EDI for wider use in nuclear applications. (author)

  12. Treatment method for stabilization of radioactive exchange resin

    International Nuclear Information System (INIS)

    Hideo, Oni; Takashi, Miyake; Hitoshi, Miyamoto; Toshio, Funakoshi; Yuzo, Inagaki.

    1988-01-01

    This is a method for eluting radioactive nuclides from a radioactive ion exchange resin in which it has been absorbed. First, the Cs in this resin is extracted using a neutral salt solution which contains Na + . The Cs that has been transferred to the neutral salt solution is absorbed and expelled by inorganic ion exchangers. Then the Co, Fe, Mn and Sr in said resin are eluted using an acidic solution; the Co, Fe, Mn and Sr that have been transferred to the acidic solution are separated from that solution by means of a diffusion dialysis vat. This process is a unique characteristic of this ion exchange resin treatment method. 1 fig

  13. Chelating ion exchange with macroreticular hydroxamic acid resins

    International Nuclear Information System (INIS)

    Phillips, R.J.

    1980-01-01

    The synthesis, reactions, and analytical applications of hydroxamic acids, including chelating resins with this functional group, are reviewed. A procedure for attaching N-phenyl hydroxamic acid groups to Amberlite XAD-4 is described. The extraction of 20 metal ions from 2 M hydrochloric acid by this resin is discussed. Conditions for the quantitative extraction and back-extraction of 9 ions are reported. Results are compared with work on solvent extraction with N-phenylbenzohydroxamic acid. Procedures for attaching N-methyl and N-unsubstituted hydroxamic acid groups to Amberlite XAD-4 are described. The N-phenyl, N-methyl, and N-unsubstituted hydroxamic acid resins are compared with respect to metal-ion complexation. The scope of applications for hydroxamic acid resins is investigated by studying the extraction of 19 metal ions as a function of pH. The resins are especially suitable for the extraction of zirconium(IV), titanium(IV), and uranium(IV) from strongly acidic solution. Aluminum(III) is separated from calcium and phosphate by extraction at pH 4. The use of the resins for the purification of reagents, concentration of trace constituents, and chromatographic separation is demonstrated

  14. 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.

  15. Immobilisation in cement of ion exchange resins arising from the purification of reagents used for the decontamination of reactor circuits

    International Nuclear Information System (INIS)

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

    1988-04-01

    The aim of the programme is to show that ion exchange resins used to remove activity from decontaminating agents used in water reactors can be successfully immobilised in cement. To achieve this, blends of Ordinary Portland Cement and ground granulated Blast Furnace Slag (ratio 9:1) have been used. Improvements in the properties of the product and the waste loading of 50 w/o damp resin can be achieved using microsilica, a finely divided form of silicon dioxide, as an additive to the blended cement. This report contains data on the effects of anion resins, and mixed anion/cation resins, on the performance of the cemented product. The effects of organic acids, especially picolinic and formic acids, bound to anion resins have also been investigated. In addition, formulations developed have been assessed at commercial scale (200 litres of cemented product) for their process and product characteristics. The final part of the report deals with the long-term product performance of samples prepared from cation resins which are now nearly one year old. (author)

  16. On the swelling behavior of cationic exchange resins saturated with Na+ ions in a C3S paste

    International Nuclear Information System (INIS)

    Lafond, E.; Cau Dit Coumes, C.; Chartier, D.; Gauffinet, S.; Le Bescop, P.; Stefan, L.

    2015-01-01

    Ion exchange resins (IERs) are widely used in the nuclear industry to decontaminate radioactive effluents. Spent resins are usually encapsulated in cementitious materials. However, the solidified waste form can exhibit strong expansion, possibly leading to cracking, if the appropriate binder is not used. In this work, the interactions between cationic resins in the Na + form and tricalcium silicate are investigated during the early stages of hydration in order to gain a better understanding of the expansion process. It is shown that the IERs exhibit a transient swelling of small magnitude due to the decrease in the osmotic pressure of the external solution. This expansion, which occurs just after setting, is sufficient to damage the material which is poorly consolidated for several reasons: low degree of hydration, precipitation of poorly cohesive sodium-bearing C-S-H, and very heterogeneous microstructure with zones of high porosity. (authors)

  17. Studies concerning the anion ex-change resins catalyzed esterification of epichlorohydrin with organic acids

    Directory of Open Access Journals (Sweden)

    E.I. Muresan

    2009-09-01

    Full Text Available The paper studies the esterification of carboxylic acids with epichlorohydrin over two macroporous strong base anion exchange resins with different polymer matrix. For both resins, the influence of reaction parameters (temperature, catalyst loading, molar ratio on the reaction rate and the yields of the two isomeric esters were investigated.

  18. A determination method of Ru, Rh and Pd in high-level liquid waste (HLLW) by cation exchange separation and ICP-AES measurement

    International Nuclear Information System (INIS)

    Cao Desheng; Duan Shirong; Qin Fengzhou; Li Jinying; Zhang Huaili

    1992-01-01

    The authors describe a determination method of Ru, Rh and Pd in HLLW with cation-exchange separation and ICP-AES measurement. A sample of HLLW was treated with the hydrochloride acid containing enough sodium chloride, then passed through a strongly acidic cation-exchange resin column, the Ru, Rh and Pd as chloro-complexes go to the eluate while the interference elements are absorbed on the resins in the column. The Ru, Rh and Pd are collected and determined by ICP-AES. The obtained results show that the recovery is 90% and the relative standard deviation is 6% as the Ru content within the range (35-230) x 10 -6 ; the recovery is 106% and RSD is 10% as the Rh content within (2-20) x 10 -6 ; and the recovery of Pd is 72% as its content less than 2 x 10 -6

  19. Separation of macro-quantities of actinide elements at Savannah River by high-pressure cation exchange

    International Nuclear Information System (INIS)

    Burney, G.A.

    1980-01-01

    Large-scale separation of actinides from fission products and from each other by pressurized cation exchange chromatography at Savannah River is reviewed. Several kilograms of 244 Cm have been separated, with each run containing as much as 150 g of 244 Cm. Dowex 50W-X8 (Dow Chemical Co.) cation resin, graded to 30-70 micron size range, is used, and separation is made by eluting with 0.05M diethylenetriamine pentaacetic acid (DTPA) at a pH of 3. The effluent from the column is continuously monitored by a BF 3 detector, a NaI detector, and a lithium-drifted germanium detector and gamma spectrometer to guide collection of product fractions. Operating the columns at 300 to 1000 psi pressure eliminates resin bed disruption caused by radiolytically produced gases, and operating at increased flow rates decreases the radiolytic degradation of the resin per unit of product processed. A portion of the hot canyon of a production radiochemical separation plant was converted from a remote crane-operated facility to a master-slave manipulator-operated facility for separation and purification of actinide elements by pressurized cation exchange. It also contains an evaporator, furnaces, a calorimeter, and several precipitators and associated tanks. Actinide processing from target dissolution to packaging of purified product is planned in this facility

  20. Evaluation of leachable behavior from ion exchange resins effects of organic impurities on BWR water chemistry. 1

    International Nuclear Information System (INIS)

    Igarashi, Hiroo; Nishimura, Yusaku; Ohsumi, Katsumi; Uchida, Shunsuke; Matsui, Tsuneo

    1999-01-01

    The elution rate of leachables from ion exchange resin, which is used in condensate demineralizers and is one of several major sources of organic compounds in BWR cooling water, was measured. Properties of the leachables and elution rate depended on the kind of ion exchange resin and the years of use. The organic compounds elution rate of cation exchange resin was constant for 5 years and the molecular weight of these leachables was low. After 5 years, the elution rate increased and leachables consisted of organic compounds of high molecular weights of several thousand. The elution rate of anion exchange resin decreased yearly. The difference in the elution behavior was attributed to a dependence on oxidation degradation promoted by transition metal catalysis. The cation exchange resin included absorbed transition metal, while the anion exchange resin did not. An empirical formula showing the time dependence of the elution rate of organic compounds was derived. The formula was judged to be appropriate based on simulations of an actual BWR plant and comparisons of impurity concentrations with actual reactor water data. (author)

  1. 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

  2. Correlation and prediction of ion exchange equilibria on weak-acid resins by means of the surface complex formation model

    International Nuclear Information System (INIS)

    Horst, J.

    1988-11-01

    The present work summarizes investigations of the equilibrium of the exchange of protons, copper, zinc, calcium, magnesium and sodium ions on two weak-acid exchange resins in hydrochloric and carbonic acid bearing solutions at 25 0 C. The description of the state of equilibrium between resin and solution is based on the individual chemical equilibria which have to be adjusted simultaneously. The equilibrium in the liquid phase is described by the mass action law and the condition of electroneutrality using activity coefficients calculated according to the theory of Debye and Hueckel. The exchange equilibria are described by means of a surface complex formation model, which was developed by Davis, James and Leckie for activated aluminia and which has been applied to weak-acid resins. The model concept assumes the resin as a plane surface in which the functional groups are distributed uniformly. (orig./RB) [de

  3. Spectrophotometric flow injection catalytic determination of molybdenum in plant digest using ion exchange resin

    International Nuclear Information System (INIS)

    Pessenda, L.C.R.

    1987-03-01

    A spectrophotometric flow injection analytical method based on the catalytic action of molybdenum on the oxidation of iodide by hydrogen peroxide in acidic medium is proposed for the molybdenum determination in plant digests. A cation exchange resin column is incorporated into a flow injection system for removal of interferents. The following system variables were investigated and optimized: reagent concentrations, sample injection volume, mixing and reaction coil lengths, temperature, sampling time, pumping rate and concentration of eluting agents. The effects of interfering species and of the acidity of samples on the molybdenum retention by the ion exchange resin column were investigated. The proposed method is characterized by good precision (r.s.d. (2.0%), a sampling rate of about 40 samples per hour, and permits the determination of molybdenum in plant digests in the range 1.0 to 40.0 μg/l. The results compare well with those obtained by graphite furnace atomic absorption spectrometry. (author) [pt

  4. Alkali metal ion-proton exchange equilibria and water sorption studies on nafon 117 membrane and dowex 50 W exchange resins: effect of long storage or aging

    International Nuclear Information System (INIS)

    Ramkumar, Jayshree; Venkataramani, B.

    2004-09-01

    Alkali metal ion -H + exchanges on Nafion 117 membrane treated differently, Dowex 50 W x 4 and Dowex 50 W x 8 resins have been studied at a total ionic strength of 0.1 mol dm -3 . The water sorption isotherms of these exchangers in different ionic forms generated over the entire range of water activity, have been analysed by the D'Arcy and Watt equation (DWE). Water sorption studies have shown that the physical structure of the exchangers have changed due to long -storage or aging, resulting in poorer water sorption and even formation of pores in the case of Dowex 50 W x 8 resin. As a result, the counter ions in the exchangers are not hydrated and the water is present in a free form, albeit structured, in the resin phase. The selectivity sequence for the alkali metal ions with reference to the H + (Li + + + ) for the exchangers used in the present study is in accordance with that reported in the literature for the ionomers having sulphonic acid as the functional group. In view of the absence of hydration of the cations in the resin phase, the driving force for the selectivity of the cation, namely, the net gain in entropy, is expected to come from the loss of structured water during the exchange process. Pre treating the Nafion 117 membrane with boiling acid solution activates the clustered region of the membrane in the H + form, while pretreatment with boiling water expands the non-ionic domain (the region connecting the clusters). These modifications influence the state of water present in the Nafion 117 membrane and the ion exchange equilibria. As a result of long storage or aging, the ion exchangers lose their elasticity or swelling characteristics. The results obtained in the present study indicate that in aged materials, the ionogenic groups are existing as isolated ion -pairs rather than in a clustered morphology. (author)

  5. Resin regenerating device in condensate desalting system

    International Nuclear Information System (INIS)

    Sato, Yoshiaki; Igarashi, Hiroo; Oosumi, Katsumi; Nishimura, Yusaku; Ebara, Katsuya; Shindo, Norikazu.

    1984-01-01

    Purpose: To improve the accuracy in the separation of anionic and cationic exchange resins. Constitution: Resins transferred from a condensate desalting column are charged in a cationic exchange resin column. The temperature of water for separating and transferring the resins is measured by a temperature detector disposed in a purified water injection line, and water is adjusted to a suitable flow rate for the separation and transfer of the resins by an automatic flow rate control valve, and then is injected. The resins are separated into cationic exchange resins and anionic exchange resins, in which only the anionic exchange resins are transferred, through an anionic exchange transfer line, into an anionic exchange resin column. By controlling the flow rate depending on the temperature of the injected water, the developing rate of the resin layer is made constant to enable separation and transfer of the resins at high accuracy. (Seki, T.)

  6. Oxidative degradation of low and intermediate level Radioactive organic wastes 2. Acid decomposition on spent Ion-Exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Ghattas, N K; Eskander, S B [Radioisotope dept., atomic energy authority, (Egypt)

    1995-10-01

    The present work provides a simplified, effective and economic method for the chemical decomposition of radioactively contaminated solid organic waste, especially spent ion - exchange resins. The goal is to achieve volume reduction and to avoid technical problems encountered in processes used for similar purposes (incineration, pyrolysis). Factors efficiency and kinetics of the oxidation of the ion exchange resins in acid medium using hydrogen peroxide as oxidant, namely, duration of treatment and the acid to resin ratio were studied systematically on a laboratory scale. Moreover the percent composition of the off-gas evolved during the decomposition process was analysed. 3 figs., 5 tabs.

  7. Oxidative degradation of low and intermediate level Radioactive organic wastes 2. Acid decomposition on spent Ion-Exchange resins

    International Nuclear Information System (INIS)

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

    1995-01-01

    The present work provides a simplified, effective and economic method for the chemical decomposition of radioactively contaminated solid organic waste, especially spent ion - exchange resins. The goal is to achieve volume reduction and to avoid technical problems encountered in processes used for similar purposes (incineration, pyrolysis). Factors efficiency and kinetics of the oxidation of the ion exchange resins in acid medium using hydrogen peroxide as oxidant, namely, duration of treatment and the acid to resin ratio were studied systematically on a laboratory scale. Moreover the percent composition of the off-gas evolved during the decomposition process was analysed. 3 figs., 5 tabs

  8. Pilot Plant for treating of spent exchange resins

    International Nuclear Information System (INIS)

    Iglesias, Alberto M.; Raffo Calderon, Maria del C.; Varani, Jose L.

    2004-01-01

    Spent exchange resins that have been accumulating during the last operational 30 years in Atucha I nuclear power plant (NPP) are a 'problematic' waste. These spent resins conform an intermediate level waste due to the total content of alpha, beta and gamma emitters (some samples of spent resins were analyzed in 2003). For this reason its treatment is more expensive since it is necessary to add more safety barriers for its final disposition and also for the radioprotection actions that are involved. Using sulfuric acid solutions it is possible to elute from the spent resins the ions that are retained. In the same operation are eluted Cobalt, Cesium and alpha emitters since that all these elements react as cations in aqueous solution. Decontamination by electrochemical methods was analyzed as an interesting method to apply after elution operation to these spent resins since that with the decontamination process it is possible to obtain a solid without activity and concentrate the activity in cells that are small in volume and its manipulation doesn't present any extra complication. Experiments made with active samples taken from the deposit were successful. Because of these results it was built a small plant to treat a batch of 100 dm 3 of wet spent exchange resins. Some problems with the material that was in the deposit together with spent resins caused that we had to plan a more complex strategy to obtain a complete decontamination of the spent resins (in this stage we used the cobalt retention cell that was described in other paper to retain Cobalt and alpha emitters and a sample of zeolites from Argentina ores to retain Cesium). Due to alpha emitters act electrochemically like cations it was possible to retain altogether with ionic Cobalt on the copper amalgam electrode. Working in the non-active lab with alcoholic solutions it was possible to retain ionic Cesium on a copper electrode (copper is covered by mercury fine film which forms a solid amalgam) with a

  9. Study of plutonium IV elution from macromolecular anion exchange resin by 0.5 M nitric acid

    International Nuclear Information System (INIS)

    Nadkarni, M.N.; Mayankutty, P.C.; Pillai, N.S.; Shinde, S.S.

    1976-01-01

    Preliminary studies indicated that macroreticular resins possess more or less the same capacities and absorption characteristics for thorium, uranium and plutonium from nitric acid solutions as the conventional resins. Detailed studies were, then, conducted. It was found that Pu(IV) can be loaded on the macroreticular anion exchange resin, Amberlyst A-26 from 7.2 M nitric acid in much the same way as Dowex 1x4. It was also observed that the elution of Pu(IV) from Amberlyst A-26 by 0.5 M nitric acid is much more rapid and quantitative than from Dowex 1x4. (author)

  10. Development, design, and preliminary operation of a resin-feed processing facility for resin-based HTGR fuels

    International Nuclear Information System (INIS)

    Haas, P.A.; Drago, J.P.; Million, D.L.; Spence, R.D.

    1978-01-01

    Fuel kernels for recycle of 233 U to High-Temperature Gas-Cooled Reactors are prepared by loading carboxylic acid cation exchange resins with uranium and carbonizing at controlled conditions. Resin-feed processing was developed and a facility was designed, installed, and operated to control the kernel size, shape, and composition by processing the resin before adding uranium. The starting materials are commercial cation exchange resins in the sodium form. The size separations are made by vibratory screening of resin slurries in water. After drying in a fluidized bed, the nonspherical particles are separated from spherical particles on vibratory plates of special design. The sized, shape-separated spheres are then rewetted and converted to the hydrogen form. The processing capacity of the equipment tested is equivalent to about 1 kg of uranium per hour and could meet commercial recycle plant requirements without scale-up of the principal process components

  11. Efficient in situ separation and production of L-lactic acid by Bacillus coagulans using weak basic anion-exchange resin.

    Science.gov (United States)

    Zhang, Yitong; Qian, Zijun; Liu, Peng; Liu, Lei; Zheng, Zhaojuan; Ouyang, Jia

    2018-02-01

    To get rid of the dependence on lactic acid neutralizer, a simple and economical approach for efficient in situ separation and production of L-lactic acid was established by Bacillus coagulans using weak basic anion-exchange resin. During ten tested resins, the 335 weak basic anion-exchange resins demonstrated the highest adsorption capacity and selectivity for lactic acid recovery. The adsorption study of the 335 resins for lactic acid confirmed that it is an efficient adsorbent under fermentation condition. Langmuir models gave a good fit to the equilibrium data at 50 °C and the maximum adsorption capacity for lactic acid by 335 resins was about 402 mg/g. Adsorption kinetic experiments showed that pseudo-second-order kinetics model gave a good fit to the adsorption rate. When it was used for in situ fermentation, the yield of L-lactic acid by B. coagulans CC17 was close to traditional fermentation and still maintained at about 82% even after reuse by ten times. These results indicated that in situ separation and production of L-lactic acid using the 335 resins were efficient and feasible. This process could greatly reduce the dosage of neutralizing agent and potentially be used in industry.

  12. Comparative study of the ionic exchange of Ca{sup ++}, Sr{sup ++}, and Ba{sup ++} cations on resins and inorganic exchangers; Etude comparative de l'echange ionique des cations Ca{sup ++}, Sr{sup ++} et Ba{sup ++} sur resine et sur echangeurs mineraux

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Batanero, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-03-01

    With a view to applying the results to certain problems related to chemical separations in activation analysis, a study has been made, of the possibilities of separating the alkaline-earth elements Ca, Sr and Ba on organic resins and inorganic exchangers using the radioactive indicator method. The partition coefficients of the cations Ca{sup 2+}, Sr{sup 2+} and Ba{sup 2+} have been measured on Dowex 50 W (NH{sub 4}{sup +}) x 8 resin in the presence of EDTA - NTA - EGTA and DCTA as complexing agents, and on zirconium phosphate, tungstate and molybdate in the presence of HCl and NH{sub 4}Cl. Methods have been developed for separating mixtures of alkaline-earth elements using DCTA-NH{sub 4}{sup +} followed by elution on Dowex 50 W (NH{sub 4}{sup +}) x 8 resin columns and on zirconium phosphate. Amongst the complexing agents used on the ion-exchange resins the most promising appears to be DCTA which leads to partition coefficients Ca, Sr and Ba which are very different. The results of measurements of partition coefficients on zirconium phosphate (NH{sub 4}{sup +} form) using DCTA-NH{sub 4}{sup +} show the interesting possibilities of separations on columns. The separation of the alkaline-earth elements on zirconium phosphate seems to be less quantitative than on Dowex 50 resin; it is however much faster in the former case and this can be useful for treating short half-life radioisotopes in activation analysis. (author) [French] En vue de l'application a certains problemes de separations chimiques en analyse par activation, on a etudie les possibilites de separation des elements alcalino-terreux Ca-Sr et Ba sur resine organique et sur echangeurs mineraux par la methode des indicateurs radioactifs. Les coefficients de partage des cations Ca{sup +2}, Sr{sup +2} et Ba{sup +2} sur resine Dowex 50 W (NH{sub 4}{sup +}) x 8 en milieux complexants EDTA - NTA - EGTA et DCTA et sur phosphate, tungstate et molybdate de zirconium en milieu HCl et NH{sub 4}Cl ont ete mesures. Des

  13. Analysis of Ion-Exchange Resin Capability of the RSG-GAS Demineralized Water System (GCA01)

    International Nuclear Information System (INIS)

    Diyah Erlina Lestari; Setyo Budi Utomo; Harsono

    2012-01-01

    The Demineralized water system (GCA01) is a system which is function to process raw water to be demineralized water using ion exchange resin unit consisting of a column of cation exchange resins, anion exchange resin column and the column resin mix bed. After certain time the ion exchange resins to be saturated so that is needed regeneration. The RSG-GAS demineralized water system (GCA01) not operated continuously and indication of when does an ion exchange resin regeneration on The RSG-GAS demineralized water system (GCA01) is the water conductivity from anion exchange resin column output indicates ≥ 5μS/cm. Analysis of capability of the ion exchange resin demineralized water system (GCA01) line I has been performed. The analysis was done by comparing the time required in the system operating cycle of regeneration to the next regeneration during the period 2011 and 2012. From the results of the analysis showed the cycle regeneration time is varies. This shows that ion exchange resin capability of the RSG-GAS demineralized water system (GCA01) is varies depending on the raw water quality and success of the regeneration ion exchange resin. (author)

  14. Rapid purification method for vitamin A-derived aging pigments A2E and iso-A2E using cation exchange resin.

    Science.gov (United States)

    Jee, Eun Hye; Kim, So Ra; Jang, Young Pyo

    2012-08-17

    A2E, known to be involved in the pathogenesis of age-related macular degeneration (AMD), is one of the major compounds that accumulate as fluorescent pigments in retinal pigment epithelial (RPE) cells with age and in some retinal disorders. While the biomimetic synthesis of A2E and its cis-isomer, iso-A2E is as simple as 'one-pot' reaction, the purification of these amphiphillic compounds has been a bottleneck for the mass production of these pathophysiologically important eye pigments. In order to provide a new method of rapid purification of A2E and iso-A2E, we employed a cation exchange resin for the separation of these pigments from crude reaction mixture. The reaction mixture was loaded on a weak acid resin and was eluted with 80% methanol with sodium hydroxide (pH 12), 100% methanol, and 100% methanol with 0.1% trifluoroacetic acid (TFA) in sequence. A2E and isoA2E were eluted only with 100% methanol solution containing TFA. Most of unreacted starting materials and intermediates were removed with 80% methanol containing sodium hydroxide. The new method can be used as a relatively simple and economic way to purify A2E and iso-A2E compared to conventional HPLC technique. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Raman spectroscopic study of the aging and nitration of actinide processing anion-exchange resins in concentrated nitric acid

    International Nuclear Information System (INIS)

    Buscher, C. T.; Donohoe, R. J.; Mecklenburg, S. L.; Berg, J. M.; Tait, C. D.; Huchton, K. M.; Morris, D. E.

    1999-01-01

    Degradation of two types of anion exchange resins, Dowex 11 and Reillex HPQ, from the action of concentrated nitric acid (4 to 12 M) and radiolysis [from depleted uranium as UO 2 2+ nitrate species and 239 Pu as Pu(IV) nitrate species] was followed as a function of time with Raman vibrational spectroscopy. Elevated temperatures (∼50 degree sign C) were used in the absence of actinide metal loading to simulate longer exposures of the resin to a HNO 3 process stream and waste storage conditions. In the absence of actinide loading, only minor changes in the Dowex resin at acid concentrations ≤10 M were observed, while at 12 M acid concentration, the emergence of a Raman peak at 1345 cm-1 indicates the addition of nitro functional groups to the resin. Similar studies with the Reillex resin show it to be more resistant to nitric acid attack at all acid concentrations. Incorporation of weakly radioactive depleted uranium as the UO 2 2+ nitrate species to the ion-exchange sites of Dowex 11 under differing nitric acid concentrations (6 to 12 M) at room temperature showed no Raman evidence of resin degradation or nitration, even after several hundred days of contact. In contrast, Raman spectra for Dowex 11 in the presence of 239 Pu as Pu(IV) nitrate species reveal numerous changes indicating resin alterations, including a new mode at 1345 cm-1 consistent with a Pu(IV)-nitrate catalyzed addition of nitro groups to the resin backbone. (c) 2000 Society for Applied Spectroscopy

  16. Modeling and simulation of protein elution in linear pH and salt gradients on weak, strong and mixed cation exchange resins applying an extended Donnan ion exchange model.

    Science.gov (United States)

    Wittkopp, Felix; Peeck, Lars; Hafner, Mathias; Frech, Christian

    2018-04-13

    Process development and characterization based on mathematic modeling provides several advantages and has been applied more frequently over the last few years. In this work, a Donnan equilibrium ion exchange (DIX) model is applied for modelling and simulation of ion exchange chromatography of a monoclonal antibody in linear chromatography. Four different cation exchange resin prototypes consisting of weak, strong and mixed ligands are characterized using pH and salt gradient elution experiments applying the extended DIX model. The modelling results are compared with the results using a classic stoichiometric displacement model. The Donnan equilibrium model is able to describe all four prototype resins while the stoichiometric displacement model fails for the weak and mixed weak/strong ligands. Finally, in silico chromatogram simulations of pH and pH/salt dual gradients are performed to verify the results and to show the consistency of the developed model. Copyright © 2018 Elsevier B.V. All rights reserved.

  17. Synthesis of 1, 4-Dioxan-2-one from 1, 3-Dioxolane and Carbon Monoxide over Cation-exchange Resin Catalyst

    OpenAIRE

    Takagi, Hiroyuki; Oumi, Yasunori; Uozumi, Toshiya; Masuda, Takashi; Sano, Tsuneji

    2001-01-01

    The possibility of the synthesis of 1, 4-dioxan-2-one (p-dioxanon) by carbonylation of 1, 3-dioxolane (cyclic ether) over Nafion® NR-50 cation-exchange resin catalyst was investigated. 1, 4-Dioxan-2-one, one of the cyclic esterethers used as a monomer of polyester, was obtained by depolymerization of polyester oligomers. The maximum yield (40%) of 1, 4-dioxan-2-one was achieved under reaction conditions of 25MPa initial PCO, 120°C reaction temperature and 4h reaction time.

  18. Radium separation through complexation by aqueous crown ethers and ion exchange or solvent extraction

    Energy Technology Data Exchange (ETDEWEB)

    Chiarizia, R.; Dietz, M.L.; Horwitz, E.P. [Argonne National Lab., IL (United States). Chemistry Div.; Burnett, W.C. [Florida State Univ., Tallahassee, FL (United States). Dept. of Oceanography

    1997-11-01

    The effect of three water-soluble, unsubstituted crown ethers (15-crown-5 (15C5), 18-crown-6 (18C6) and 21-crown-7 (21C7)) on the uptake of Ca, Sr, Ba and Ra cations by a sulfonic acid cation exchange resin, and on the extraction of the same cations by xylene solutions of dinonylnaphthalenesulfonic acid (HDNNS) from aqueous hydrochloric acid solutions has been investigated. The crown ethers enhance the sorption of the larger cations by the ion exchange resin, thereby improving the resin selectivity over calcium, a result of a synergistic interaction between the crown ether and the ionic functional groups of the resin. Similarly, the extraction of the larger alkaline earth cations into xylene by HDNNS is strongly synergized by the presence of the crown ethers in the aqueous phase. Promising results for intra-Group IIa cation separations have been obtained using each of the three crown ethers as the aqueous ligands and the sulfonic acid cation exchange resin. Even greater separation factors for the radium-calcium couple have been measured with the crown-ethers and HDNNS solutions in the solvent extraction mode. The application of the uptake and extraction results to the development of radium separation schemes is discussed and a possible flowchart for the determination of {sup 226}Ra/{sup 228}Ra in natural waters is presented.

  19. Disintegration and dissolution of spent radioactive cationic exchange resins using Fenton-like oxidation process

    International Nuclear Information System (INIS)

    Wan, Zhong; Xu, Lejin; Wang, Jianlong

    2015-01-01

    Highlights: • The spent radioactive resins could be oxidized by Fenton-like process. • The influencing factors on resin oxidation were evaluated. • Chemical oxygen demand (COD) reduction rate was more than 99%. • SEM and Raman spectrum were used to analyze the resins morphological change. - Abstract: The treatment and disposal of the spent radioactive resins is essential for the sustainable development of the nuclear industry. In this paper, the disintegration and dissolution of spent cationic resins were studied by Fenton-like process. The influencing factors on resin dissolution, such as pH, temperature, type and concentration of catalysts were evaluated. The results showed that the spent resins could be effectively dissolved at pH < 1, [Fe 2+ ] = 0.2 M and T = 97 ± 2 °C. Chemical oxygen demand (COD) reduction rate was more than 99%. The scanning electron microscopy and the Raman spectrum were used to observe the morphological changes of the spent resins during the dissolution process. Fenton-like oxidation is an efficient method for the volume reduction and stabilization of the spent resins before further immobilization

  20. Disintegration and dissolution of spent radioactive cationic exchange resins using Fenton-like oxidation process

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Zhong; Xu, Lejin [Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084 (China); Wang, Jianlong, E-mail: wangjl@tsinghua.edu.cn [Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing 100084 (China)

    2015-09-15

    Highlights: • The spent radioactive resins could be oxidized by Fenton-like process. • The influencing factors on resin oxidation were evaluated. • Chemical oxygen demand (COD) reduction rate was more than 99%. • SEM and Raman spectrum were used to analyze the resins morphological change. - Abstract: The treatment and disposal of the spent radioactive resins is essential for the sustainable development of the nuclear industry. In this paper, the disintegration and dissolution of spent cationic resins were studied by Fenton-like process. The influencing factors on resin dissolution, such as pH, temperature, type and concentration of catalysts were evaluated. The results showed that the spent resins could be effectively dissolved at pH < 1, [Fe{sup 2+}] = 0.2 M and T = 97 ± 2 °C. Chemical oxygen demand (COD) reduction rate was more than 99%. The scanning electron microscopy and the Raman spectrum were used to observe the morphological changes of the spent resins during the dissolution process. Fenton-like oxidation is an efficient method for the volume reduction and stabilization of the spent resins before further immobilization.

  1. Cation Exchange Efficiency Of Modified Bentonite Using In-Situ GAMMA Radiation Polymerization Of Acrylic Acid Or Acrylamide

    International Nuclear Information System (INIS)

    ISMAIL, S.A.; FALAZI, B.

    2009-01-01

    Modified bentonites as cation exchangers were prepared by treating raw bentonite with 3N NaOH at 95 0 C followed by in-situ polymerization using gamma irradiation as well as hydrogen peroxide initiation of acrylic acid or acrylamide in the matrix.Water swelling and acid capacity were determined and cation exchange capacity for Cu 2+ , Ni 2+ and Co 2+ was evaluated. It has been found that catiexchange capacity of treated bentonite was increased as result of formed polyacrylic acid and polyacrylamide in the matrix. In case of acrylic acid, the maximum cation exchange capacities of 3.5, 3.1 and 2.5 mg equivalent/g were determined for Cu 2+ , Ni 2+ and Co 2+ , respectively, and for acrylamide, the corresponding capacities were 2.9, 2.8 and 2.6 mg equivalent/g, respectively. Water swelling was found to be associated with holding large amounts of water, for instance, 49 g of water was sorbed per one gram of the sodium salt form of polyacrylic acid in bentonite matrix, in other words the degree of swelling in water achieved 4500%.

  2. 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

  3. Purification of Anthocyanins with o-Dihydroxy Arrangement by Sorption in Cationic Resins Charged with Fe(III

    Directory of Open Access Journals (Sweden)

    Araceli Castañeda-Ovando

    2014-01-01

    Full Text Available In the present work, a new purification method of anthocyanins with o-dihydroxy arrangement is proposed. This method is based on a ligand-exchange mechanism, using a cationic exchange resin loaded with metallic ions in order to increase the affinity of the resin to the anthocyanin(s with o-dihydroxy arrangement. This method was used to purify the main anthocyanin (cyanidin-3-glucoside; Cy-3-glc from the anthocyanic methanolic extract of blue corn. The best sorption result was using Fe(III in its ion form. The purification procedure begins with the formation of a metal-anthocyanin complex (Cy-3-glc-Fe which was optimal at pH 5, followed by a NaOH 0.1 M elution process in order to eliminate anthocyanins without o-dihydroxy arrangement, sugars, and organic acids. Finally, the pure anthocyanin is obtained by adding HCl 0.1 M which breaks the metal-anthocyanin complex.

  4. The removal of toxic metals from liquid effluents by ion exchange resins. Part V: Nickel(II/H+/Dowex C400

    Directory of Open Access Journals (Sweden)

    Francisco José Alguacil

    2017-11-01

    Full Text Available The cationic exchange resin Dowex C400 was used to remove nickel(II from aqueous solutions of different pH values and under various experimental conditions: stirring speed of the aqueous solution/resin system, temperature, resin dosage and aqueous ionic strength. The selectivity of the resin was investigated against the presence of various metals in the aqueous solution, and the removal of nickel(II from aqueous solutions was also compared with results obtained using multiwalled carbon nanotubes or functionalized (carboxylic groups multiwalled carbon nanotubes as adsorbents. According to batch experimental data, best fit of the results is obtained with the Freundlich model, whereas the ion exchange process is best explained by the pseudo-first order model. Experimental data fit well to the moving boundary controlled model. Elution of the nickel(II loaded onto Dowex C400 resin is fully possible using acidic solutions.

  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. Novel simple process for tocopherols selective recovery from vegetable oils by adsorption and desorption with an anion-exchange resin.

    Science.gov (United States)

    Hiromori, Kousuke; Shibasaki-Kitakawa, Naomi; Nakashima, Kazunori; Yonemoto, Toshikuni

    2016-03-01

    A novel and simple low-temperature process was used to recover tocopherols from a deodorizer distillate, which is a by-product of edible oil refining. The process consists of three operations: the esterification of free fatty acids with a cation-exchange resin catalyst, the adsorption of tocopherols onto an anion-exchange resin, and tocopherol desorption from the resin. No degradation of tocopherols occurred during these processes. In the tocopherol-rich fraction, no impurities such as sterols or glycerides were present. These impurities are commonly found in the product of the conventional process. This novel process improves the overall recovery ratio and the mass fraction of the product (75.9% and 51.0wt%) compared with those in the conventional process (50% and 35wt%). Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. 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.

  8. Removal of CdTe in acidic media by magnetic ion-exchange resin: A potential recycling methodology for cadmium telluride photovoltaic waste

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Teng, E-mail: zhangteng@mail.iee.ac.cn; Dong, Zebin; Qu, Fei; Ding, Fazhu; Peng, Xingyu; Wang, Hongyan; Gu, Hongwei

    2014-08-30

    Highlights: • Sulfonated magnetic microsphere was prepared as one strong acid cation-exchange resin. • Cd and Te can be removed directly from the highly acidic leaching solution of CdTe. • Good chemical stability, fast adsorbing rate and quick magnetic separation in strong acidic media. • A potential path for recycling CdTe photovoltaic waste. - Abstract: Sulfonated magnetic microspheres (PSt-DVB-SNa MPs) have been successfully prepared as adsorbents via an aqueous suspension polymerization of styrene-divinylbenzene and a sulfonation reaction successively. The resulting adsorbents were confirmed by means of Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope equipped with an energy dispersive spectrometer (SEM-EDS) and vibrating sample magnetometer (VSM). The leaching process of CdTe was optimized, and the removal efficiency of Cd and Te from the leaching solution was investigated. The adsorbents could directly remove all cations of Cd and Te from a highly acidic leaching solution of CdTe. The adsorption process for Cd and Te reached equilibrium in a few minutes and this process highly depended on the dosage of adsorbents and the affinity of sulfonate groups with cations. Because of its good adsorption capacity in strong acidic media, high adsorbing rate, and efficient magnetic separation from the solution, PSt-DVB-SNa MPs is expected to be an ideal material for the recycling of CdTe photovoltaic waste.

  9. Cation mobility in H+/Na+ ion exchange products of acid tantalum and zirconium phosphates

    International Nuclear Information System (INIS)

    Tarnopol'skij, V.A.; Yaroslavtsev, A.B.

    2000-01-01

    Ionic conductivity of Na + /H + exchange products on acid zirconium phosphate with different substitution degree and on acid tantalum phosphate, where ion exchange occurs via formation of a continuous series of solid solutions, was studied by the method of conductometry. It was ascertained that ionic conductivity decreases monotonously with growth in substitution degree of H + for Na + in acid tantalum phosphate. Anomalous increase in ionic conductivity of ion exchange products on acid zirconium phosphate with a low substitution degree has been detected for the first time. Formation of a double electric layer with a high concentration of cationic defects on the interface surface is the reason for increase in ionic conductivity [ru

  10. 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)

  11. 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

  12. Separation of boron isotopes using NMG type anion exchange resin

    International Nuclear Information System (INIS)

    Itagaki, Takaharu; Kosuge, Masao; Fukuda, Junji; Fujii, Yasuhiko.

    1992-01-01

    Ion exchange separation of boron isotopes (B-10 and B-11) has been studied by using a special boron selective ion exchange resin; NMG (n-methyl glucamine)-type anion exchange resin. The resin has shown a large isotope separation coefficient of 1.02 at the experimental conditions of temperature, 80degC, and boric acid concentration, 0.2 M (mole/dm 3 ). Enriched B-10 (92%) was obtained after the migration of 1149 m by a recyclic operation of ion exchange columns in a merry-go-round method. (author)

  13. Behavior of copper (II )and uranium ( VI) in precipitation chromatography in the system anion exchange resin - hexacyanoferrate (II )

    International Nuclear Information System (INIS)

    Seneda, Jose Antonio

    1997-01-01

    In this work it is shown the efficiency of precipitation chromatography for separation and concentration of metallic elements by using a strong anionic-exchange resin saturated with hexacyanoferrate (II). Metallic cations, like Cu (II) and U (VI), are retained from highly diluted solutions and enriched into the resin, in the form of the correspondent insoluble hexacyanoferrate (II), precipitated inside the resin, which permitted the visual observation of a chromatographic zone on the top of the column. It will be discussed the conditions of sorption and elution of the cations uptake by the resin. This system permits the enrichment of the above mentioned cations onto the resin and offers the possibility of interesting separations as well. (author)

  14. Process for removing a mixture containing iodine and alkyl iodine compounds from a gas phase or aqueous solution with ion-exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, H; Mizuuchi, A; Yokoyama, F

    1968-10-04

    Iodine and alkyl iodine compounds are removed from a gas phase or aqueous solution containing salts, iodine and iodine compounds, such as the ambient gas in a reactor, if an accident should occur. The process comprises contacting the phase or solution: (a) with a hydrogen type strongly acidic cationic exchange resin, (b) with an anionic exchange resin containing quarternary ammonium and (c) with an anionic exchange resin containing free basic type tertiary amine, in this order or by reversing the order of the two anionic exchange resins. Although no problems arise in the liquid phase reaction, the ion-exchange resins in the gas phase reaction are desired in the moist state in order to stable maintain the migration speed of the materials to be removed regardless of the relative humidity of the amibent gas. In example I, Amberlite IRA-900 of 200 mm thickness as the lowermost bed, Amberlite IRA93 of 200 mm thickness as the middle bed and Amberlite 200 of 200 mm thickness as the uppermost bed were filled respectively, in a methacrylate resin cylinder with an inner diameter of 25 mm. A solution containing 15.9 mg/1 of iodine, 41.2 mg/1 of methyl iodide and 550 mg/1 of sodium carbonate flows at a rate of 15 liter/hr downward through the beds. As a result of testing, no iodine, iodine ions, iodic acid ions and methyl iodine were detected. The amount of water the beds could treat was 60 times the total quantity of the filled resins.

  15. Esterification of Palmitic Acid with Methanol in the Presence of Macroporous Ion Exchange Resin as Catalyst

    Directory of Open Access Journals (Sweden)

    Amelia Qarina Yaakob and Subhash Bhatia

    2012-10-01

    Full Text Available The esterification of palmitic acid with methanol was studied in a batch reactor using macro porous ion exchange resin Amberlyst 15 as a catalyst. Methyl palmitate was produced from the reaction between palmitic acid and methanol in the presence of catalyst. The effects of processing parameters, molar ratio of alcohol to acid M, (4-10, catalyst loading (0-10 g cat/liter, water inhibition (0-2 mol/liter, agitator speed (200-800 rpm and reaction temperature (343-373K were studied. The experimental kinetic data were correlated using homogenous as well as heterogeneous models (based on single as well as dual site mechanisms. The activation energy of the reaction was 11.552 kJ/mol for forward reaction whilst 5.464 kJ/mol for backward reaction. The experimental data fitted well with the simulated data obtained from the kinetic models. Keywords: Palmitic Acid, Methanol, Esterification, Ion Exchange Resin, Kinetics.

  16. Ion-exclusion/cation-exchange chromatography with dual detection of the conductivity and spectrophotometry for the simultaneous determination of common inorganic anionic species and cations in river and wastewater.

    Science.gov (United States)

    Nakatani, Nobutake; Kozaki, Daisuke; Mori, Masanobu; Hasebe, Kiyoshi; Nakagoshi, Nobukazu; Tanaka, Kazuhiko

    2011-01-01

    Simultaneous determinations of common inorganic anionic species (SO(4)(2-), Cl(-), NO(3)(-), phosphate and silicate) and cations (Na(+), NH(4)(+), K(+), Mg(2+) and Ca(2+)) were conducted using an ion-chromatography system with dual detection of conductivity and spectrophotometry in tandem. The separation of ionic species on a weakly acidic cation-exchange resin was accomplished using a mixture of 100 mM ascorbic acid and 4 mM 18-crown-6 as an acidic eluent (pH 2.6), after which the ions were detected using a conductivity detector. Subsequently, phosphate and silicate were analyzed based on derivatization with molybdate and spectrophotometry at 700 nm. The detection limits at S/N = 3 ranged from 0.11 to 2.9 µM for analyte ionic species. This method was applied to practical river water and wastewater with acceptable criteria for the anion-cation balance and comparisons of the measured and calculated electrical conductivity, demonstrating the usefulness of the present method for water quality monitoring.

  17. Removal of Uranium by Exchanger Resins from Soil Washing Solution

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seung Soo; Han, G. S.; Kim, G. N.; Koo, D. S.; Jeong, J. W.; Moon, J. K. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-05-15

    Uranyl ions in the acidic waste solution were sorbed on AM-resin resin with a high sorption efficiency, and desorbed from the resin by a batch-type washing with a 60 .deg. C heated 0.5 M Na{sub 2}CO{sub 3} solution. However, the uranium dissolved in the sulfuric acid solution was not sorbed onto the strong anion exchanger resins. Our group has developed a decontamination process with washing and electrokinetic methods for uranium-contaminated (U-contaminated) soil. However, this process generates a large amount of waste solution containing various metal ions. If the uranium selectively removed from the waste solution, a very small amount of the 2nd waste would be generated. Thus, selective sorption of uranium by ion exchange resins was examined in this study.

  18. Influence of the Functionalization Degree of Acidic Ion-Exchange Resins on Ethyl Octyl Ether Formation

    Czech Academy of Sciences Publication Activity Database

    Guilera, J.; Hanková, Libuše; Jeřábek, Karel; Ramírez, E.; Tejero, J.

    2014-01-01

    Roč. 78, MAY (2014), s. 14-22 ISSN 1381-5148 Grant - others:SEURDO(ES) CTQ2010-16047 Institutional support: RVO:67985858 Keywords : acidic ion - exchange resin * sulfonation degree * ISEC Subject RIV: CC - Organic Chemistry Impact factor: 2.515, year: 2014

  19. Cycloaliphatic epoxide resins for cationic UV - cure

    International Nuclear Information System (INIS)

    Verschueren, K.; Balwant Kaur

    1999-01-01

    This paper introduces the cyclo - aliphatic epoxide resins used for the various applications of radiation curing and their comparison with acrylate chemistry. Radiation curable coatings and inks are pre - dominantly based on acrylate chemistry but over the last few years, cationic chemistry has emerged successfully with the unique properties inherent with cyclo - aliphatic epoxide ring structures. Wide variety of cationic resins and diluents, the formulation techniques to achieve the desired properties greatly contributes to the advancement of UV - curing technology

  20. Diphonix trademark Resin: A review of its properties and applications

    International Nuclear Information System (INIS)

    Chiarizia, R.; Horwitz, E.P.; Alexandratos, S.D.

    1995-01-01

    The recently developed Diphonix trademark resin is a new multifunctional chelating ion exchange resin containing seminally substituted diphosphonic acid ligands chemically bonded to a styrene-based polymeric matrix. Diphonix can be regarded as a dual mechanism polymer, with a sulfonic acid cation exchange group allowing for rapid access, mostly non-specific, of ions into the polymeric network, and the diphosphonic acid group responsible for specificity (recognition) for a number of metal cations. The Diphonix resin exhibits an extraordinarily strong affinity for actinides, especially in the tetra- and hexavalent oxidation states. It has potential applications in TRU and mixed waste treatment and characterization, and in the development of new procedures for rapid actinide preconcentration and separation from environmental samples. Metal uptake studies have been extended to alkaline earth cations, to transition and post transition metal species, and to metal sorption from neutral or near neutral solutions. Also the kinetic behavior of the resin has been investigated in detail. Influence of the most commonly occurring matrix constituents (Na, Ca, Al, Fe, hydrofluoric, sulfuric, oxalic and phosphoric acids) on the uptake of actinide ions has been measured. This review paper summarizes the most important results studies on the Diphonix resin and gives an overview of the applications already in existence or under development in the fields of mixed waste treatment, actinide separation procedures, treatment of radwaste from nuclear power plants, and removal of iron from copper electrowinning solutions

  1. Effect of the chemical structure of anion exchange resin on the adsorption of humic acid: behavior and mechanism.

    Science.gov (United States)

    Shuang, Chendong; Wang, Jun; Li, Haibo; Li, Aimin; Zhou, Qing

    2015-01-01

    Polystyrenic (PS) anion-exchange resin and polyacrylic (PA) anion-exchange resin were used to investigate the effect of resin chemical structure on the adsorption of humic acid (HA). Due to the rearrangement of HA to form layers that function as barricades to further HA diffusion, PS resin exhibited 12.4 times slower kinetics for the initial adsorption rate and 8.4 times for the diffusion constant in comparison to that of the PA resin. An HA layer and a spherical cluster of HA can be observed on the surface of the PS and PA resins after adsorption, respectively. The considerable difference in HA adsorption between the PS and PA resins was due to the difference in molecule shape for interaction with different resin structures, which can essentially be explained by the hydrophobicity and various interactions of the PS resin. A given amount of HA occupies more positively charged sites and hydrophobic sites on the PS resin than were occupied by the same amount of HA on the PA resin. Increased pH resulted in an increase of HA adsorption onto the PA resin but a decrease in adsorption onto PS resin, as the non-electrostatic adsorption led to electrostatic repulsion between the HA attached to the resin and the HA dissolved in solution. These results suggest higher rates of adsorption and higher regeneration efficiency for interaction of HA with more hydrophilic anion exchange materials. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. 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)

  3. Processing of indium (III solutions via ion exchange with Lewatit K-2621 resin

    Directory of Open Access Journals (Sweden)

    López Díaz-Pavón, Adrián

    2014-06-01

    Full Text Available The processing of indium(III-hydrochloric acid solutions by the cationic ion exchange Lewatit K-2621 resin has been investigated. The influence of several variables such as the hydrochloric acid and metal concentrations in the aqueous solution and the variation of the amount of resin added has been studied. Moreover, a kinetic study performed in the uptake of indium(III by Lewatit K-2621, shows that either the film-diffusion and the particle-diffusion models fit the ion exchange process onto the resin, depending upon the initial metal concentration in the aqueous solution. The loaded resin could be eluted by HCl solutions at 20 °C.Se ha investigado el tratamiento de disoluciones de ácido clorhídrico conteniendo indio(III mediante la resina de cambio catiónico Lewatit K-2621. Las variables ensayadas han sido las concentraciones de ácido y de metal en la disolución acuosa y la cantidad de resina empleada en el tratamiento de dichas disoluciones. Asimismo, se ha llevado a cabo un estudio cinético del proceso de intercambio catiónico entre el indio(III y la resina Lewatit K-2621. Este estudio muestra que el proceso de intercambio responde a un mecanismo de difusión en la disolución o en la partícula de resina dependiendo de la concentración inicial del metal en el medio acuoso. El metal cargado en la resina puede ser eluido con disoluciones de ácido clorhídrico a 20 °C.

  4. On the swelling of ion exchange resins used in Swedish nuclear power plants

    International Nuclear Information System (INIS)

    Nilsson, A.C.; Hoegfeldt, E.; Muhammed, M.

    1988-03-01

    Ion exchange resins are used in nuclear power plants for purification and decontamination of water. In some of the cases, the spent resins are solidified by drying at elevated temperatures and then molded together with bitumen before final disposal. The objective of the present work is to study the swelling behavior of such resins and describe it with a model that permits calculation of the water uptake into the bituminized resins and the external swelling pressure that might develop by the swelling resins under repository conditions. The experimental part of the study comprises the swelling of ion exchange resins upon their exposure to water vapour before and after thermal treatment under conditions simulating those used in the various solidification processes. Seven different resins were studied in different chemical forms; H + , N + and OH - , So 4 2- for the cation an anion exchangers respectively. For each resin, water uptake, density and volume were measured at different water activities at 25 degrees C. The swelling pressure for all resins studied was calculated. A slight increase in swelling pressure after thermal treatment could be observed, especially for anion exchangers. The apparent molar volume of water in the resin phase has been determined and the swelling free energies of swelling has been calculated from experimental data at 25 degrees C and estimated at 0 degrees C. (authors)

  5. Removing and recovering of uranium from the acid mine waters by using ion exchange resin; Remocao e recuperacao de uranio de aguas acidas de mina por resina de troca ionica

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Marcos Roberto Lopes do

    1998-07-01

    Ion exchange using resins is one of the few processes capable of reducing ionic contaminants in effluents to very low levels. In this study the process was used to remove and recovery uranium from acid mine waters at Pocos de Caldas-MG Uranium Mining and Milling Plant. The local mineralogical features, allied to the biogeochemical phenomena, owing to presence of pyrite in the rock piles, moreover another factors, resulting acid drainage with several pollutants, including uranium ranging from 6 to 14 mg/l, as sulfate complex, that can be removed by anionic exchanger. The iron interference is eliminated by lime pretreatment of water, increasing pH from 2.6 to 3.3-3.8 to precipitate this cation, without changing the uranium amount. Eight anionic resins were tested, based on the uranium loading, in sorption studies. Retention time, and pH influence was verified for the exchanger chose. With breakthrough of 1 mg U/L and 10 mg U/l in the feed solution, the uranium decontamination level was 94%. Typical values of loading resin were 20-30 g U/l and 70-90 g SO{sub 4}/l. Uranium elution was done with Na Cl solution. Retention time, saline, and acid concentration were the parameters studied. The concentrate, obtained from the eluate by ammonia precipitation, presented uranium (86,8% as U{sub 3} O{sub 8}) and impurities within commercial specifications. (author)

  6. 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

  7. Irradiation effects in the storage and disposal of radioactive ion-exchange resins

    International Nuclear Information System (INIS)

    Swyler, K.J.; Dodge, C.E.; Dayal, R.; Weiss, A.J.

    1982-01-01

    Research is under way to characterize the effects of self-irradiation on radwastes which may be generated when organic ion-exchange media are used in water demineralization or decontamination operations at nuclear facilities. External factors affecting the relation between laboratory evaluations and field performance are emphasized. Initial experiments do not yet indicate substantial radiation dose-rate effects on radiolytic gas yields or acid product formation, when (fully swollen) sulfonic acid resins are irradiated in a sealed air environment. At the same time, oxygen gas is removed from the environment of irradiated resins. Interaction between mild steel coupons and acidic species produced in the irradiation induced decomposition of sulfonic acid resin results in irradiation enhanced corrosion. Corrosion rates depend on radiation dose rate, moisture content and resin chemical loading. In some cases, corrosion rates decrease with time, suggesting depletion of acidic species within the resin bed, or a synergistic interaction between resin and corrosion coupon. Implications of these and other results on evaluating field behavior of radwaste containing ion-exchange media are discussed. 4 figures, 2 tables

  8. Esterification of phenyl acetic acid with p-cresol using metal cation exchanged montmorillonite nanoclay catalysts.

    Science.gov (United States)

    Bhaskar, M; Surekha, M; Suma, N

    2018-02-01

    The liquid phase esterification of phenyl acetic acid with p -cresol over different metal cation exchanged montmorillonite nanoclays yields p -cresyl phenyl acetate. Different metal cation exchanged montmorillonite nanoclays (M n +  = Al 3+ , Zn 2+ , Mn 2+ , Fe 3+ , Cu 2+ ) were prepared and the catalytic activity was studied. The esterification reaction was conducted by varying molar ratio of the reactants, reaction time and catalyst amount on the yield of the ester. Among the different metal cation exchanged catalysts used, Al 3+ -montmorillonite nanoclay was found to be more active. The characterization of the material used was studied under different techniques, namely X-ray diffraction, scanning electron microscopy and thermogravimetric analysis. The product obtained, p -cresyl phenyl acetate, was identified by thin-layer chromotography and confirmed by Fourier transform infrared, 1 H NMR and 13 C NMR. The regeneration activity of used catalyst was also investigated up to fourth generation.

  9. 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)

  10. Carboxylic acid exchangers in analytical chemistry

    International Nuclear Information System (INIS)

    Venkateswarlu, Ch.

    1976-01-01

    The literature on the use of carboxylic acid exchangers in inorganic analytical chemistry is reviewed. It is classified under two heads, based on the ionic form in which the exchanger is employed, viz., the salt form and the acid form. In the salt form, the separations reported in the beginning are mostly carried out in alkaline medium, employing ammonia and its derivatives as complexing agents to hold cations in solution. This was followed by the use of ammonium ion as an eluent from heavy weakly or neutral solutions. There are a few separations reported making use of EDTA as eluent. It appears that separation of some anions from cations can be achieved with greater ease with these exchangers than with sulphonic acid type. Contary to the general belief, carboxylic acid exchangers are used in H + form to achieve some analytical separations of cations of interest. These exchangers exhibit better sorption of some cations in presence of complexing agents containing basic nitrogen as a donor. In fact, a careful study of these exchangers with different matrices might yield really selective exchangers, than the chelating ones known commercially. From the separation cited, carboxylic acid exchangers appear to have greater potentialities in their applications, than what is normally expected. (author)

  11. Wet oxidative destruction of spent ion-exchange resins using hydrogen peroxide

    International Nuclear Information System (INIS)

    Srinivas, C.; Ramaswamy, M.; Theyyunni, T.K.

    1994-01-01

    Spent organic ion exchange resins are generated in large quantities during the operation of nuclear facilities. Wet oxidation as a mode of treatment of these gel-type ion exchange resins was investigated using H 2 O 2 as oxidant in the presence of CuSO 4 as catalyst. Experiments using commercial samples were conducted at 95-100 deg C under reflux conditions at atmospheric pressure. It was found that the reaction of cation resin with H 2 O 2 was instantaneous whereas with anion resin, there was a lag time. For efficient utilization of the oxidant, low rate of addition of H 2 O 2 , 0.01M concentration of CuSO 4 and neutral pH in mixed resin reactions, were found to be useful. Foaming was noted during reactions involving anion resins. This could be controlled by silicone-based agents. The residual solution left after resin oxidation is aqueous in nature and is expected to contain all the radioactivity originally present in the resin. Preliminary experiments showed that it could be efficiently trapped using available inorganic sorbents. Wet oxidation system offers a simple method of converting organic waste into environmentally acceptable inorganic products. (author). 8 refs., 6 figs., 2 tabs

  12. EPICOR-II resin degradation results from first resin samples of PF-8 and PF-20

    International Nuclear Information System (INIS)

    McConnell, J.W. Jr.; Sanders, R.D. Sr.

    1985-12-01

    The 28 March 1979 accident at Three Mile Island Unit 2 released approximately 560,000 gallons of contaminated water to the Auxiliary and Fuel Handling Buildings. The water was decontaminated using a demineralization system called EPICOR-II developed by Epicor, Inc. The Low-Level Waste Data Base Development - EPICOR-II Resin/Liner Investigation Project is studying the chemical and physical conditions of the synthetic ion exchange resins found in several EPICOR-II prefilters. This report summarizes results and analyses of the first sampling of ion exchange resins from EPICOR-II prefilters PE-8 and -20. Results are compared with baseline data from tests performed on unirradiated Epicor, Inc. resins to determine if degradation has occurred due to the high internal radiation dose received by the EPICOR-II resins. Results also are compared with recent findings on resin degradation by Battelle Columbus Laboratories and Brookhaven National Laboratory. Analyses comparing test results of resins from EPICOR-II prefilters PF-8 and -20 with unirradiated resins obtained from Epicor, Inc. show resin degradation has occurred in some of the EPICOR-II resins examined. The mechanism of degradation is compared with work of other researchers and is consistent with their findings. The strong acid cation resins (divinylbenzene, styrene base structure) are losing effective cross-linking along with scission of functional groups and are experiencing first an increase and eventually a decrease in total exchange capacity as the absorbed radiation dose increases. The phenolic cation resins (phenol-formaldehyde base structure) show a loss of effective cross-linking and oxidation of the polymer chain. Analyses of resins removed from EPICOR-II prefilters PF-8 and -20 over the next several years should show a further increase in degradation

  13. Diclofenac removal in urine using strong-base anion exchange polymer resins.

    Science.gov (United States)

    Landry, Kelly A; Boyer, Treavor H

    2013-11-01

    One of the major sources of pharmaceuticals in the environment is wastewater effluent of which human urine contributes the majority of pharmaceuticals. Urine source separation has the potential to isolate pharmaceuticals at a higher concentration for efficient removal as well as produce a nutrient byproduct. This research investigated the efficacy of using strong-base anion exchange polymer resins to remove the widely detected and abundant pharmaceutical, diclofenac, from synthetic human urine under fresh and ureolyzed conditions. The majority of experiments were conducted using a strong-base, macroporous, polystyrene resin (Purolite A520E). Ion-exchange followed a two-step removal rate with rapid removal in 1 h and equilibrium removal in 24 h. Diclofenac removal was >90% at a resin dose of 8 mL/L in both fresh and ureolyzed urine. Sorption of diclofenac onto A520E resin was concurrent with desorption of an equivalent amount of chloride, which indicates the ion-exchange mechanism is occurring. The presence of competing ions such as phosphate and citrate did not significantly impact diclofenac removal. Comparisons of three polystyrene resins (A520E, Dowex 22, Dowex Marathon 11) as well as one polyacrylic resin (IRA958) were conducted to determine the major interactions between anion exchange resin and diclofenac. The results showed that polystyrene resins provide the highest level of diclofenac removal due to electrostatic interactions between quaternary ammonium functional groups of resin and carboxylic acid of diclofenac and non-electrostatic interactions between resin matrix and benzene rings of diclofenac. Diclofenac was effectively desorbed from A520E resin using a regeneration solution that contained 4.5% (m/m) NaCl in an equal-volume mixture of methanol and water. The greater regeneration efficiency of the NaCl/methanol-water mixture over the aqueous NaCl solution supports the importance of non-electrostatic interactions between resin matrix and benzene rings

  14. 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

  15. Efficiency of lead removal from drinking water using cationic resin Purolite

    Directory of Open Access Journals (Sweden)

    Ashour Mohammad Merganpour

    2015-01-01

    Full Text Available Background: Today, issues such as water shortage, difficulties and costs related to supplying safe water, and anomalous concentrations of heavy metals in groundwater and surface water resources, doubled the necessity of access to technical methods on removing these pollutants from water resources. Methods: In this lab study, cationic resin Purolite S-930 (with co-polymer styrene di-vinyl benzene structure was used for lead removal from drinking water containing up to 22 μg/L. Using statistical analysis and designing a full factorial experiment are the most important effective parameters on lead removal obtained through ion exchange process. Results: Analysis of response and interaction parameters of ion exchange showed that the resin column height has maximum and pH value has minimum effect on the efficiency of lead removal from aquatic environment. Trinary interaction of “effective size, flow rate, resin column high” has the most important for lead removal efficiency in this system. So the maximum efficiency was obtained at the mesh = 40, bed height =1.6 meter, and pH= 6.5. At the best operation conditions, ability to remove 95.42% of lead concentration can be achieved. Conclusion: Using the resin Purolite S-930 during 21-day service with 91.12% of mean lead removal ratio from drinking water is an economic and technical feasibility.

  16. High-capacity cation-exchange column for enhanced resolution of adjacent peaks of cations in ion chromatography.

    Science.gov (United States)

    Rey, M A

    2001-06-22

    One of the advantages of ion chromatography [Anal Chem. 47 (1975) 1801] as compared to other analytical techniques is that several ions may be analyzed simultaneously. One of the most important contributions of cation-exchange chromatography is its sensitivity to ammonium ion, which is difficult to analyze by other techniques [J. Weiss, in: E.L. Johnson (Ed.), Handbook of Ion Chromatography, Dionex, Sunnyvale, CA, USA]. The determination of low concentrations of ammonium ion in the presence of high concentrations of sodium poses a challenge in cation-exchange chromatography [J. Weiss, Ion Chromatography, VCH, 2nd Edition, Weinheim, 1995], as both cations have similar selectivities for the common stationary phases containing either sulfonate or carboxylate functional groups. The task was to develop a new cation-exchange stationary phase (for diverse concentration ratios of adjacent peaks) to overcome limitations experienced in previous trails. Various cation-exchange capacities and column body formats were investigated to optimize this application and others. The advantages and disadvantages of two carboxylic acid columns of different cation-exchange capacities and different column formats will be discussed.

  17. Investigation of the swelling behavior of cationic exchange resins saturated with Na{sup +} ions in a C{sub 3}S paste

    Energy Technology Data Exchange (ETDEWEB)

    Lafond, E. [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Cau Dit Coumes, C., E-mail: celine.cau-dit-coumes@cea.fr [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Gauffinet, S. [UMR5209 Institut Carnot de Bourgogne, Université de Bourgogne Dijon, Faculté des Sciences Mirande, 9 Avenue Alain Savary, BP 47870, 21078 Dijon cedex (France); Chartier, D. [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Le Bescop, P. [CEA, DEN, DPC, SECR, F-91192 Gif-sur-Yvette (France); Stefan, L. [AREVA, Back End Business Group, Dismantling & Services, 1 place Jean Millier, 92084 Paris La Défense (France); Nonat, A. [UMR5209 Institut Carnot de Bourgogne, Université de Bourgogne Dijon, Faculté des Sciences Mirande, 9 Avenue Alain Savary, BP 47870, 21078 Dijon cedex (France)

    2015-03-15

    Ion exchange resins (IERs) are widely used by the nuclear industry to decontaminate radioactive effluents. Spent products are usually encapsulated in cementitious materials. However, the solidified waste form can exhibit strong expansion, possibly leading to cracking, if the appropriate binder is not used. In this work, the interactions between cationic resins in the Na{sup +} form and tricalcium silicate are investigated during the early stages of hydration in order to gain a better understanding of the expansion process. It is shown that the IERs exhibit a transient swelling of small magnitude due to the decrease in the osmotic pressure of the external solution. This expansion, which occurs just after setting, is sufficient to damage the material which is poorly consolidated for several reasons: low degree of hydration, precipitation of poorly cohesive sodium-bearing C–S–H, and very heterogeneous microstructure with zones of high porosity.

  18. Transformation of thorium sulfate in thorium nitrate by ion exchange resin

    International Nuclear Information System (INIS)

    Pereira, W.

    1991-01-01

    A procedure for transforming thorium sulfate into thorium nitrate by means of a strong cationic ion exchanger is presented. The thorium sulfate solution (approximately 15 g/L Th (SO 4 ) 2 ) is percolate through the resin and the column is washed first with water, with a 0,2 M N H 4 OH solution and then with a 0.2 M N H 4 NO 3 solution in order to eliminate sulfate ion. Thorium is eluted with a 2 M solution of (N H 4 ) 2 CO 3 . This eluate is treated with a solution of nitric acid in order to obtain the complete transformation into Th (NO 3 ) 4 . The proposed procedure leads to good quality thorium nitrate with high uranium decontamination. (author)

  19. Ion exchange resins destruction in a stirred supercritical water oxidation reactor

    International Nuclear Information System (INIS)

    Leybros, A.; Roubaud, A.; Guichardon, P.; Boutin, O.

    2010-01-01

    Spent ion exchange resins (IERs) are radioactive process wastes for which there is no satisfactory industrial treatment. Supercritical water oxidation offers a viable treatment alternative to destroy the organic structure of resins, used to remove radioactivity. Up to now, studies carried out in supercritical water for IER destruction showed that degradation rates higher than 99% are difficult to obtain even using a catalyst or a large oxidant excess. In this study, a co-fuel, isopropanol, has been used in order to improve degradation rates by initiating the oxidation reaction and increasing temperature of the reaction medium. Concentrations up to 20 wt% were tested for anionic and cationic resins. Total organic carbon reduction rates higher than 99% were obtained from this process, without the use of a catalyst. The influence of operating parameters such as IERs feed concentration, nature and counterions of exchanged IERs were also studied. (authors)

  20. Chemical reactivity of cation-exchanged zeolites

    OpenAIRE

    Pidko, E.A.

    2008-01-01

    Zeolites modified with metal cations have been extensively studied during the last two decades because of their wide application in different technologically important fields such as catalysis, adsorption and gas separation. Contrary to the well-understood mechanisms of chemical reactions catalyzed by Brønsted acid sites in the hydrogen forms of zeolites, the nature of chemical reactivity, and related, the structure of the metal-containing ions in cation-exchanged zeolites remains the subject...

  1. Reducing nitrogen crossover in microbial reverse-electrodialysis cells by using adjacent anion exchange membranes and anion exchange resin

    KAUST Repository

    Wallack, Maxwell J.; Geise, Geoffrey M.; Hatzell, Marta C.; Hickner, Michael A.; Logan, Bruce E.

    2015-01-01

    Microbial reverse electrodialysis cells (MRECs) combine power generation from salinity gradient energy using reverse electrodialysis (RED), with power generation from organic matter using a microbial fuel cell. Waste heat can be used to distill ammonium bicarbonate into high (HC) and low salt concentration (LC) solutions for use in the RED stack, but nitrogen crossover into the anode chamber must be minimized to avoid ammonia loses, and foster a healthy microbial community. To reduce nitrogen crossover, an additional low concentration (LC) chamber was inserted before the anode using an additional anion exchange membrane (AEM) next to another AEM, and filled with different amounts of anion or cation ion exchange resins. Addition of the extra AEM increased the ohmic resistance of the test RED stack from 103 Ω cm2 (1 AEM) to 295 Ω cm2 (2 AEMs). However, the use of the anion exchange resin decreased the solution resistance of the LC chamber by 74% (637 Ω cm2, no resin; 166 Ω cm2 with resin). Nitrogen crossover into the anode chamber was reduced by up to 97% using 50% of the chamber filled with an anion exchange resin compared to the control (no additional chamber). The added resistance contributed by the use of the additional LC chamber could be compensated for by using additional LC and HC membrane pairs in the RED stack.

  2. Hydration effect on ion exchange resin irradiated by swift heavy ions and gamma rays

    Science.gov (United States)

    Boughattas, I.; Labed, V.; Gerenton, A.; Ngono-Ravache, Y.; Dannoux-Papin, A.

    2018-06-01

    Gamma radiolysis of ion exchange resins (IER) is widely studied since the sixties, as a function of different parameters (resin type, dose, atmosphere, water content …). However, to our knowledge, there are very few data concerning hydrogen emission from anionic and cationic resins irradiated at high Linear Energy Transfers (LET). In the present work, we focus on the influence of hydration on hydrogen emission, in anionic and cationic resins irradiated under inert atmosphere using Swift Heavy Ions (SHI) and gamma irradiations. The radiation chemical yield of molecular hydrogen is nonlinear with water content for both resins. The molecular hydrogen production depends first on the water form in IER (free or linked) and second on the solubility of degradation products. Three steps have been observed: at lower water content where G(H2) is stable, at 50%, G(H2) increases due to reactions between water radiolytic species and the resin functional groups and at high water content, G(H2) decreases probably due to its accumulation in water and its consumption by hydroxyl radicals in the supernatant.

  3. Fractionation of lithium isotopes in cation-exchange chromatography

    International Nuclear Information System (INIS)

    Oi, Takao; Kawada, Kazuhiko; Kakihana, Hidetake; Hosoe, Morikazu

    1991-01-01

    Various methods for lithium isotope separation have been developed, and their applicability to large-scale enriched lithium isotope production has been assessed. Ion-exchange chromatography is one such method. Cation-exchange chromatography of lithium was carried out to investigate the lithium isotope effect in aqueous ion-exchange systems. The heavier isotope. 7 Li, was preferentially fractionated into the resin phase in every experiment conducted, and this result is consistent with the results of previous work. The value of the separation factor was 1.00089-1.00171 at 25C. A comparison of lithium isotope effect with those of potassium and rubidium indicated that the isotope effect originating from hydration is larger than the effect due to phase change for lithium, while the opposite is the case with potassium and rubidium

  4. Esterification of free fatty acids in waste cooking oils (WCO): Role of ion-exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Nalan Ozbay; Nuray Oktar; N. Alper Tapan [Gazi University, Ankara (Turkey). Faculty of Engineering and Architecture, Department of Chemical Engineering

    2008-08-15

    Although WCO plays a crucial role for the economical production of biodiesel, free fatty acid (FFA) level in the nature of WCO cause saponification problems during transesterification. Acidic ion-exchange resins can be used to decrease WCO free fatty acid level. In this study, activities of resins (Amberlyst-15 (A-15), Amberlyst-35 (A-35), Amberlyst-16 (A-16) and Dowex HCR-W2) in direct FFA esterification were examined in the temperature range of 50-60{sup o}C and the effect of catalyst amount (1-2 wt%) on FFA conversion was also analyzed. FFA conversion increased with increasing reaction temperature and catalyst amount. Order of catalytic activities was found as A-15 > A-35 > A-16 > Dowex HCR-W2. This was related to the size of average pore diameters and magnitude of BET surface area. 44 refs., 11 figs., 2 tabs.

  5. Ammonia vapor sensing properties of polyaniline-titanium(IV)phosphate cation exchange nanocomposite.

    Science.gov (United States)

    Khan, Asif Ali; Baig, Umair; Khalid, Mohd

    2011-02-28

    In this study, the electrically conducting polyaniline-titanium(IV)phosphate (PANI-TiP) cation exchange nanocomposite was synthesized by sol-gel method. The cation exchange nanocomposite based sensor for detection of ammonia vapors was developed at room temperature. It was revealed that the sensor showed good reversible response towards ammonia vapors ranging from 3 to 6%. It was found that the sensor with p-toluene sulphonic acid (p-TSA) doped exhibited higher sensing response than hydrochloric acid doped. This sensor has detection limit ≤1% ammonia. The response of resistivity changes of the cation exchange nanocomposite on exposure to different concentrations of ammonia vapors shows its utility as a sensing material. These studies suggest that the cation exchange nanocomposite could be a good material for ammonia sensor at room temperature. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. 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)

  7. Separation of uranium and other metals from commercial phosphoric acid by ion-exchange and voltammetric determination of uranium

    International Nuclear Information System (INIS)

    Ferreira, J.B.C.; Carvalho, F.M.S. de; Abrao, A.

    1985-11-01

    The separation of metals from crude commercial phosphoric acid is achieved by simple dilution and percolation through a strong cationic ion exchanger. Uranium, calcium, magnesium, manganese, iron and aluminum are quantitatively fixed by the exchanger and can be detected or analysed after their complete elution with 6 M HCI. Titanium and zirconium are only partially retained. Specially for its separation and determination uranium is retained selectively by the resin from the phosphoric acid-EDTA solution, the column is washed with water and then eluted with hydrochloric acid. Uranium is analyzed by voltametry with the hanging drop mercury electrode. (Author) [pt

  8. Kinetics of destruction of KU-2 x 8 and AV-17 x 8 ion-exchange resins by the joint action of heating and irradiation

    International Nuclear Information System (INIS)

    Tulupov, P.E.; Butenko, T.Yu.

    1982-01-01

    Experimental data indicates a decrease of the exchange capacity of AV-17 x 8 (OH) resin in ion-exchange beds at various temperatures. Losses of exchange of the resin in hydroxyl form after 10,000h of continuous heating at 60, 70, and 80 0 C are 24, 44, and 78% respectively. Partial replacement of the hydroxyl by the salt form is accomplished by appreciable lowering of capacity losses. The trimethlyamine evolved during deamination of AV-17 x 8 anion exchange resin, and only methanol, enters the coolant. Under the influence of ionizing radiation in the active zone the methanol will be converted successively into formaldehyde, formic acid and CO 2 . Thus the maximum temperature of use of the hydroxyl form of te anion-exchange resin AV-17 x 8 (OH) in nuclear power plants can be raised to 70-75 0 C. Brief changes of temperature at 100 0 C do not cause any appreciable losses of exchange capacity either. Physicochemical properties of ion-exchange resins after use in nuclear power plants leads to excessive and unjustified restriction of their service life in the course of a single cycle. Joint action of heating and irradiation on AV-17 anion-exchange resin was studied. It was found that rate constants of the processes of thermal radiation decreases the exchange capacities of the resins in the temperature ranges of interest with relation to nuclear power plants. Calculation of the stability of KU-2 x 8 cation-exchange resin shows that even after a year of use at 100 0 C the loss of its exchange capacity is less than 0.1%. Therefore, under the conditions of use in a nuclear power plant KU-2 x 8 resin can be regarded as absolutely stable. The loss of exchange capacity of AV-17 x 8 resin in C1 form at 100 0 C is of similar magnitude

  9. 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

  10. 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.

  11. Pyrolysis and oxidative pyrolysis experiments with organization exchange resin

    International Nuclear Information System (INIS)

    Chun, Ung Kyung

    1997-01-01

    Pyrolysis may be an important pretreatment step before vitrification in a cold crucible melter (CCM). During vitrification of organic resin the carbon or other remaining residues may harm the performance of the cold crucible melter of the eventual stability of the final glass product. Hence, it is important to reduce or prevent such harmful waste from entry into the cold crucible melter. Pretreatment with pyrolysis will generally provide volume reduction resulting in less amount of solid waste that needs to be handled by the CCM; in addition, the pyrolytic processes may breakdown much of the complex organics causing release through volatilization resulting in less carbon and other harmful substances. Hence, KEPRI has undertaken studies on the pyrolysis and oxidative pyrolysis of organic ion exchange resin. Pyrolysis and oxidative pyrolysis were examined with TGA and a tube furnace. TGA results for pyrolysis with the flow of nitrogen indicate that even after pyrolyzing from room temperature to about 900 deg C, a significant mass fraction of the original cationic resin remains, approximately 46 %. The anionic resin when pyrolytically heated in a flow of nitrogen only, from room temperature to about 900 deg C, produced a final residue mass fraction of about 8 percent. Oxidation at a ratio of air to nitrogen, 1:2, reduced the cationic resin to 5.3% when heated at 5 C/min. Oxidation of anionic resin at the same ratio and same heating rate left almost no solid residue. Pyrolysis (e.g. nitrogen-only environment) in the tube furnace of larger samples relative to the TGA produced very similar results to the TGA. The differences may be attributed to the scale effects such as surface area exposure to the gas stream, temperature distributions throughout the resin, etc. (author) 7 refs., 7 figs

  12. Pyrolysis and oxidative pyrolysis experiments with organization exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Ung Kyung [Korea Electric Power Research Insititute, Taejon (Korea, Republic of)

    1997-12-31

    Pyrolysis may be an important pretreatment step before vitrification in a cold crucible melter (CCM). During vitrification of organic resin the carbon or other remaining residues may harm the performance of the cold crucible melter of the eventual stability of the final glass product. Hence, it is important to reduce or prevent such harmful waste from entry into the cold crucible melter. Pretreatment with pyrolysis will generally provide volume reduction resulting in less amount of solid waste that needs to be handled by the CCM; in addition, the pyrolytic processes may breakdown much of the complex organics causing release through volatilization resulting in less carbon and other harmful substances. Hence, KEPRI has undertaken studies on the pyrolysis and oxidative pyrolysis of organic ion exchange resin. Pyrolysis and oxidative pyrolysis were examined with TGA and a tube furnace. TGA results for pyrolysis with the flow of nitrogen indicate that even after pyrolyzing from room temperature to about 900 deg C, a significant mass fraction of the original cationic resin remains, approximately 46 %. The anionic resin when pyrolytically heated in a flow of nitrogen only, from room temperature to about 900 deg C, produced a final residue mass fraction of about 8 percent. Oxidation at a ratio of air to nitrogen, 1:2, reduced the cationic resin to 5.3% when heated at 5 C/min. Oxidation of anionic resin at the same ratio and same heating rate left almost no solid residue. Pyrolysis (e.g. nitrogen-only environment) in the tube furnace of larger samples relative to the TGA produced very similar results to the TGA. The differences may be attributed to the scale effects such as surface area exposure to the gas stream, temperature distributions throughout the resin, etc. (author) 7 refs., 7 figs.

  13. Removal of plutonium from nitric acid-oxalic acid solutions using anion exchange method

    International Nuclear Information System (INIS)

    Kasar, U.M.; Pawar, S.M.; Joshi, A.R.

    1999-01-01

    An anion exchange method using Amberlyst A-26 (MP) resin was developed for removal of Pu from nitric acid-oxalic acid solutions without destroying oxalate. The method consists of sorption of Pu(IV) on Amberlyst A-26, a macroporous anion exchange resin, from nitric acid-oxalic acid medium in the presence of Al(NO 3 ) 3 . Pu(IV) breakthrough capacity of Amberlyst A-26 using synthetic feed solution was determined. (author)

  14. Optimization of acidified oil esterification catalyzed by sulfonated cation exchange resin using response surface methodology

    International Nuclear Information System (INIS)

    Ma, Lingling; Han, Ying; Sun, Kaian; Lu, Jie; Ding, Jincheng

    2015-01-01

    Highlights: • As lipid source, acidified oil are from industrial wastes for renewable energy. • The predicted conversion rate of FFAs was 75.24% under the RSM optimized conditions. • The adsorption system was employed to remove the water produced to shift the equilibrium toward ethyl ester production. • Maximum conversion rate of 98.32% was obtained using adsorption system at optimum process parameters. • Compared with tradition methods, molecular sieve dehydration method improved the conversion rate by 23.08%. - Abstract: The esterification of acidified oil with ethanol catalyzed by sulfonated cation exchange resins (SCER) was optimized using the response surface methodology (RSM). The effects of the molar ratio of ethanol to acidified oil, reaction time and catalyst loading on the conversion rate of free fatty acids (FFAs) were investigated at the temperature of the boiling point of ethanol. Results showed that the highest conversion rate of 75.24% was obtained at the molar ratio of ethanol to acidified oil of 23.2, reaction time of 8.0 h and catalyst loading of 35.0 wt.%. Moreover, the conversion rate of FFAs was increased to 98.32% by using a water adsorption apparatus under the RSM optimized conditions. Scanning electronic microscopic–energy dispersive spectrometric (SEM–EDS), X-ray diffractometric (XRD) and thermogravimetric–derivative thermogravimetric (TG–DTG) analyses confirmed that the morphology of catalysts did not change much and the mechanical and thermal stabilities were still good after the reaction. Furthermore, SCER exhibited a high catalytic activity and stability after being reused for five successive times. The fuel properties of the biodiesel were comparable to that of ASTM, EN and GB biodiesel standard

  15. Cation exchange separation of 16 rare earth metals by microscale high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Ishii, D.; Hirose, A.; Iwasaki, Y.

    1978-01-01

    The separation of rare earth metals has been studied with a microcolumn of 0.5 mm i.d. and 75 mm length, packed with TSK LS-212 high-performance cation exchange resin. A micro-feeder (Model MF-2, from Azumadenki Kogyo) was used to drive carrier and sample solutions through the ion exchange column and detection cell. By combining a 250 μl syringe and a 0.5 mm i.d. sampling tube the micro-feeder, 0.1-1.0 μl rare earth metals were separated within 38 min, using only 304 μl of 0.4M α-hydroxy-isobutyric acid solution adjusted to pH 3.1-6.0 with ammonia solution as gradient carrier solution. The gradient elution was successfully performed by applying a new technique developed for microscale liquid chromatography. (author)

  16. Determination of degradation conditions of exchange resins containing technetium

    International Nuclear Information System (INIS)

    Rivera S, A.; Monroy G, F.; Quintero P, E.

    2014-10-01

    The quantification of Tc-99 in spent exchange resins, coming from nuclear power plants, is indispensable to define their administration. The Tc-99 is a pure beta emitter of 210000 years of half-life, volatile and of a high mobility in water and soil. For this reason, the objective of this work is to establish a digestion method of ionic exchange resins containing technetium that retains more than 95% of this radioisotope. Mineralization tests were carried out of a resin Amberlite IRN-150 by means of an oxidation heat, in acid medium, varying the resin mass, the medium volume, the media type, the temperature and the digestion time. The digested samples were analyzed by gas chromatography to estimate the grade of their degradation. The 99m Tc was used as tracer to determine the technetium percentage recovered after mineralizing the resin. The digestion process depends on the temperature and the resin mass. At higher temperature better mineralization of samples and to greater resin mass to a constant temperature, less degradation of the resin. The spectra beta of the 99m Tc and 99 Tc are presented. (Author)

  17. 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

  18. 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)

  19. 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)

  20. Release of organics from BWR condensate demineralizer resins

    International Nuclear Information System (INIS)

    Ohira, Taku; Furukawa, Makoto; Sekiguchi, Masahiko; Takiguchi, Hideki; Deguchi, Tatsuya; Ino, Takao; Izumi, Takeshi; Hagiwara, Masahiro

    1998-01-01

    In BWRs, one of major factors to affect water chemistry in reactor is the organics leaching from condensate demineralizer. Especially, the organics from cation ion exchange resin (described CER hereafter) is intaken to reactor and changes to the sulfuric acid due to thermal decomposition and radiolysis, because CER contains sulfuric groups. In this paper, the influence of environmental parameters and structure of ion exchange resin (described IER hereafter) on the organics leaching are clarified by using 'the new method' developed for accurate measurement organics leaching from IER. Based on these results, the mechanism of the organics leaching from IER is discussed. (author)

  1. 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

  2. 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)

  3. 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

  4. Determination of airborne, volatile amines from polyurethane foams by sorption onto a high-capacity cation-exchange resin based on poly(succinic acid).

    Science.gov (United States)

    Seeber, G; Buchmeiser, M R; Bonn, G K; Bertsch, T

    1998-06-05

    A high-capacity carboxylic acid-functionalized resin prepared by ring-opening metathesis polymerization based on cross-linked endo,endo-poly(norborn-2-ene-5,6-dicarboxylic acid) was used for the sampling of volatile, airborne amines from polyurethane (PU) foams. Six tertiary amines which represent commonly used promotors for the formation of PUs from diisocyanates and polyols, namely pentamethyldiethylenetriamine, diazabicyclooctane, N-methylmorpholine, N-ethylmorphine, 1,4-dimethylpiperazine and N,N-dimethylethanolamine, were sorbed onto the new resin. The sorption behavior of the new material was investigated in terms of loading capacities, the influence of concentration, flow-rate as well as of the amount of resin. Breakthrough curves were recorded from each single component as well as of mixtures thereof. Finally, the resin was used for the sampling of amines evaporating from PU foams applied in buildings. Further information about time dependent concentration profiles were obtained using a combination of GC-MS and Fourier transform IR spectroscopy.

  5. Design and assembling of a moving bed column to operate with ion exchange resin

    International Nuclear Information System (INIS)

    Franca Junior, J.M.; Abrao, A.

    1976-01-01

    A new moving bed column specially designed to operate with ion exchange resins in such peculiar situations where there is gas evolution is reported. The second part reports the use of the column in the preparation of nuclear grade ammonium uranyl tricarbonate (AUTC), from crude uranyl nitrate solution. Uranium-VI is binded into a strong cationic ion exchanger and then eluted with (NH 4 ) 2 CO 3 . The final product is crystallized from the eluate by simply cooling down the temperature to 5 0 or by addition of ethanol. Loading of resin with uranyl ion, its elution with ammonium carbonate and the crystallization of AUTC is described [pt

  6. 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

    ionogenic groups that make up sRF. Recent literature reviews and scoping titration tests strongly indicate that sRF is a polyfunctional cation exchange resin with at least three dominant types of ring groups playing a role in its isotherm behavior over the wide pH range of operations. Also three types of fixed ionogenic acid groups are present: sulfonic (SO 3 H - ) groups; carboxylic (COOH - ) groups, and resorcylic (OH - ) groups. It is this premise that we are working under in the development of a robust isotherm model for sRF over its entire planned pH operating range. The application of prototypic isotherms for modeling ion-exchange column behavior is demonstrated in Section 3 of this report. This preliminary work served to focus the development effort on the use of a mass-action based isotherm. In Section 4 of this report, the foundational material required to develop a robust isotherm model for sRF is provided. The paths taken, and choices made, are given for the reader to better understand our current status with respect to this goal and to highlight our most recent understanding of sRF exchange equilibria. Our ultimate goal is to update the CERMOD code (Aleman and Hamm, 2007) with a robust isotherm model for sRF that spans the entire pH and concentration ranges of planned operations. The isotherm model will then be used in the VERSE-LC code to model an entire ion-exchange cycle.

  7. DEVELOPMENT OF AN APPROACH TO MODELING LOADING AND ELUTION OF SPHERICAL RESORCINOL FORMALDEHYDE ION-EXCHANGE RESIN

    Energy Technology Data Exchange (ETDEWEB)

    Aleman, S.; Hamm, L.; Smith, F.

    2011-10-03

    fixed ionogenic groups that make up sRF. Recent literature reviews and scoping titration tests strongly indicate that sRF is a polyfunctional cation exchange resin with at least three dominant types of ring groups playing a role in its isotherm behavior over the wide pH range of operations. Also three types of fixed ionogenic acid groups are present: sulfonic (SO{sub 3}H{sup -}) groups; carboxylic (COOH{sup -}) groups, and resorcylic (OH{sup -}) groups. It is this premise that we are working under in the development of a robust isotherm model for sRF over its entire planned pH operating range. The application of prototypic isotherms for modeling ion-exchange column behavior is demonstrated in Section 3 of this report. This preliminary work served to focus the development effort on the use of a mass-action based isotherm. In Section 4 of this report, the foundational material required to develop a robust isotherm model for sRF is provided. The paths taken, and choices made, are given for the reader to better understand our current status with respect to this goal and to highlight our most recent understanding of sRF exchange equilibria. Our ultimate goal is to update the CERMOD code (Aleman and Hamm, 2007) with a robust isotherm model for sRF that spans the entire pH and concentration ranges of planned operations. The isotherm model will then be used in the VERSE-LC code to model an entire ion-exchange cycle.

  8. 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

  9. 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.

  10. Esterification of maleic acid and butanol using cationic exchange ...

    Indian Academy of Sciences (India)

    AARTI MULAY

    2017-11-15

    Nov 15, 2017 ... Special Issue on Recent Trends in the Design and Development of Catalysts and their Applications ... non-corrosive and eco-friendly nature, easy to separate and no ... of heterogeneous catalysts using ion exchange resin. ... The reactor was continu- ... 2.3a Gas chromatographic analysis: The liquid sam-.

  11. The radiolytic and chemical degradation of organic ion exchange resins under alkaline conditions: effect on radionuclide speciation

    International Nuclear Information System (INIS)

    Loon, L. van; Hummel, W.

    1995-10-01

    The formation of water soluble organic ligands by the radiolytic and chemical degradation of several ion exchange resins was investigated under conditions close to those of the near field of a cementitious repository. The most important degradation products were characterised and their role on radionuclide speciation evaluated thoroughly. Irradiation of strong acidic cation exchange resins (Powdex PCH and Lewatite S-100) resulted in the formation of mainly sulphate and dissolved organic carbon. A small part of the carbon (10-20%) could be identified as oxalate. The identity of the remainder is unknown. Complexation studies with Cu 2+ and Ni 2+ showed the presence of two ligands: oxalate and ligand X. Although ligand X could not be identified, it could be characterised by its concentration, a deprotonation constant and a complexation constant for the NiX complex. The influence of oxalate and ligand X on the speciation of radionuclides is examined in detail. For oxalate no significant influence on the speciation of radionuclides is expected. The stronger complexing ligand X may exert some influence depending on its concentration and the values of other parameters. These critical parameters are discussed and limiting values are evaluated. In absence of irradiation, no evidence for the formation of ligands was found. Irradiation of strong basic anion exchange resins (Powdex PAO and Lewatite M-500) resulted in the formation of mainly ammonia, amines and dissolved organic carbon. Up to 50% of the carbon could be identified as methyl-, dimethyl- and trimethylamine. Complexation studies with Eu 3+ showed that the complexing capacity under near field conditions was negligible. The speciation of cations such as Ag, Ni, Cu and Pd can be influenced by the presence of amins. The strongest amine-complexes are formed with Pd and therefore, as an example, the aqueous Pd-ammonia system is examined in great detail. (author) 30 figs., 10 tabs., refs

  12. Studies of cation exchange for the isolation and concentration of trace level components of complex aqueous mixtures

    International Nuclear Information System (INIS)

    Kaczvinsky, J.R. Jr.

    1984-01-01

    Trace level organic bases are concentrated from aqueous solution by cation exchange on a column of sulfonated macroreticular XAD-4 resin. Washing of the column with organic solvents removes neutrals and acids. Ammonia gas is introduced into the column prior to elution of the basic organics with either methanol or ether containing ammonia. After solvent evaporation, the concentrated sample is analyzed by gas chromatography. Recoveries of over 85% are found with at least one of the eluents for over 50 bases tested at levels < 1 ppm. Improved recoveries and reproducibility are seen over a simple ether extraction procedure. Samples of river water, shale oil process water, and supernatant from an agricultural chemical disposal pit are analyzed. Preliminary studies of functionalized poly(styrene-divinylbenzene)s, coated exchangers, and liquid ion exchangers as possible approaches to nuclear waste decontamination are performed

  13. 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)

  14. USE OF STRONG ACID RESIN PUROLITE C100E FOR REMOVING PERMANENT HARDNESS OF WATER – FACTORS AFFECTING CATIONIC EXCHANGE CAPACITY

    Directory of Open Access Journals (Sweden)

    BOGDAN BANDRABUR

    2013-12-01

    Full Text Available This paper experimentally investigates the performance and capacity of Purolite C100E commercial resin recommended for water softening applications in the food industry. The practical ion exchange capacity and the softening process efficiency are studied in batch mode as a function of the sorption specific process factors. Optimum operation conditions were determined as initial pH 7.1, resin dose 8 g dry resin•L-1, temperature 25 oC, contact time of 360 min, and in those conditions the retention capacity for the Ca2+ ions is 17.18 mg•g-1 that corresponds to a removal efficiency equal to 85.7%.

  15. Speciation and surface interactions of actinides on aged ion-exchange resins

    International Nuclear Information System (INIS)

    Morris, D.E.; Buscher, C.T.; Donohoe, R.J.

    1997-01-01

    The United States Department of Energy is presently faced with the stabilization and safe disposition of hundreds of metric tons of residue materials resulting from 50+ years of nuclear weapons production activities. These residues encompass a broad range of substrates and radionuclides and include both solid and liquid materials. Combustible residues constitute a significant fraction of the total residue inventory, and an important constituent within the combustible category is spent anion ion-exchange resins. These resins are typically utilized for the separation of plutonium from other radionuclides under strongly acidic nitric or hydrochloric acid solution conditions which favor the formation and partitioning of anionic Pu(IV) nitrato or chloride species. The spent resins are usually rinsed prior to storage as residues to reduce both acid and radionuclide concentrations, but significant radionuclide concentrations remain in these resins, and the long-term effects of concentrated acid and radiolysis on the resin integrity are relatively unexplored. Thus, new research is needed to assess the stability of these resin residues and address the need for further treatment to ensure stability prior to long-term disposal

  16. 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)

  17. Development of a treatment process for the removal of heavy metals from raw water for drinking water supply using chelating ion exchange resins. Subproject 1. Final report; Entwicklung der Verfahrenstechnik zur Eliminierung von Schwermetallen aus Rohwaessern zur Trinkwassergewinnung mit chelatbildenden Kationenaustauscherharzen zur technischen Reife. Teilprojekt 1. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Overath, H.; Stetter, D.; Doerdelmann, O.

    2002-07-01

    Chelating cation exchange resins with iminodiacetic acid group (Lewatit TP 207 and Amberlite IRC 748) were tested for the removal of heavy metals in a drinking water treatment plant. The pilot scale filtration experiments were conducted by varying the operating conditions, such as flow rate and feed concentrations. Heavy metal concentrations (nickel, lead, cadmium, zinc) in the feed were adjusted between 20 and 200 {mu}g/L. Different methods for regeneration and conditioning of the resins were developed and investigated. Finally the ion exchange resins were tested according to German health regulations for ion exchangers in drinking water treatment. (orig.)

  18. 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.

  19. Selection of anion exchangers for detoxification of dilute-acid hydrolysates from spruce.

    Science.gov (United States)

    Horváth, Ilona Sárvári; Sjöde, Anders; Nilvebrant, Nils-Olof; Zagorodni, Andrei; Jönsson, Leif J

    2004-01-01

    Six anion-exchange resins with different properties were compared with respect to detoxification of a dilute-acid hydrolysate of spruce prior to ethanolic fermentation with Saccharomyces cerevisiae. The six resins encompassed strong and weak functional groups as well as styrene-, phenol-, and acrylic-based matrices. In an analytical experimental series, fractions from columns packed with the different resins were analyzed regarding pH, glucose, furfural, hydroxymethylfurfural, phenolic compounds, levulinic acid, acetic acid, formic acid, and sulfate. An initial adsorption of glucose occurred in the strong alkaline environment and led to glucose accumulation at a later stage. Acetic and levulinic acid passed through the column before formic acid, whereas sulfate had the strongest affinity. In a preparative experimental series, one fraction from each of six columns packed with the different resins was collected for assay of the fermentability and analysis of glucose, mannose, and fermentation inhibitors. The fractions collected from strong anion-exchange resins with styrene-based matrices displayed the best fermentability: a sevenfold enhancement of ethanol productivity compared with untreated hydrolysate. Fractions from a strong anion exchanger with acrylic-based matrix and a weak exchanger with phenol-based resin displayed an intermediate improvement in fermentability, a four- to fivefold increase in ethanol productivity. The fractions from two weak exchangers with styrene- and acrylic-based matrices displayed a twofold increase in ethanol productivity. Phenolic compounds were more efficiently removed by resins with styrene- and phenol-based matrices than by resins with acrylic-based matrices.

  20. SOLVENT EFFECTS IN THE LIQUID-PHASE HYDRATION OF CYCLOHEXENE CATALYZED BY A MACROPOROUS STRONG ACID ION-EXCHANGE RESIN

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    1992-01-01

    The liquid-phase hydration of cyclohexene, a pseudo first order reversible reaction catalyzed by a strong acid ion exchange resin, macroporous Amberlite XE 307, was investigated in solvent mixtures of water and sulfolane. A decrease by a factor of 3 and 6 is observed in the experimentally measured

  1. Possible mechanisms for the interaction of polymeric composite resins with Cu(II) ions in aqueous solution

    International Nuclear Information System (INIS)

    El-Zahhhar, A.A.; Abdel-Aziz, H.M.; Siyam, T.

    2005-01-01

    The interaction between the active groups of polymeric composite resins such as Poly(acrylamide-acrylic acid)-ethylenediaminetetra acetic acid disodium salt P(AM-AA)EDTANa 2 , Poly(acrylamide-acrylic acid)- montmorillonite P(AM-AA)-montmorillonite, and Poly(acrylamide-acrylic acid)-potassium nickel hexacyanoferrate P(AM-AA)-KNiHCF, with copper sulfate as a test ion has been studied. The spectroscopic studies show that the mechanism of interaction between polymeric composite resins and copper sulfate is a bond formation between the active groups of polymeric chains and copper ion. The bond formation depends on nature of polymeric chains. It was also found that the amide groups form complexes with hydrated cations, while carboxylate group interact by ion exchange mechanism through complex formation. Montmorillonite and hexacyanoferrate of the resins interact with metal ions by ion exchange mechanism

  2. Decontamination of spent ion-exchangers contaminated with cesium radionuclides using resorcinol-formaldehyde resins.

    Science.gov (United States)

    Palamarchuk, Marina; Egorin, Andrey; Tokar, Eduard; Tutov, Mikhail; Marinin, Dmitry; Avramenko, Valentin

    2017-01-05

    The origin of the emergence of radioactive contamination not removable in the process of acid-base regeneration of ion-exchange resins used in treatment of technological media and liquid radioactive waste streams has been determined. It has been shown that a majority of cesium radionuclides not removable by regeneration are bound to inorganic deposits on the surface and inside the ion-exchange resin beads. The nature of the above inorganic inclusions has been investigated by means of the methods of electron microscopy, IR spectrometry and X-ray diffraction. The method of decontamination of spent ion-exchange resins and zeolites contaminated with cesium radionuclides employing selective resorcinol-formaldehyde resins has been suggested. Good prospects of such an approach in deep decontamination of spent ion exchangers have been demonstrated. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Factorial experimental design for recovering heavy metals from sludge with ion-exchange resin

    International Nuclear Information System (INIS)

    Lee, I.H.; Kuan, Y.-C.; Chern, J.-M.

    2006-01-01

    Wastewaters containing heavy metals are usually treated by chemical precipitation method in Taiwan. This method can remove heavy metals form wastewaters efficiently, but the resultant heavy metal sludge is classified as hazardous solid waste and becomes another environmental problem. If we can remove heavy metals from sludge, it becomes non-hazardous waste and the treatment cost can be greatly reduced. This study aims at using ion-exchange resin to remove heavy metals such as copper, zinc, cadmium, and chromium from sludge generated by a PCB manufacturing plant. Factorial experimental design methodology was used to study the heavy metal removal efficiency. The total metal concentrations in the sludge, resin, and solution phases were measured respectively after 30 min reaction with varying leaching agents (citric acid and nitric acid); ion-exchange resins (Amberlite IRC-718 and IR-120), and temperatures (50 and 70 deg. C). The experimental results and statistical analysis show that a stronger leaching acid and a higher temperature both favor lower heavy metal residues in the sludge. Two-factors and even three-factor interaction effects on the heavy metal sorption in the resin phase are not negligible. The ion-exchange resin plays an important role in the sludge extraction or metal recovery. Empirical regression models were also obtained and used to predict the heavy metal profiles with satisfactory results

  4. Laboratory studies on enhancing the throughput of demineraliser units by proper selection of ion exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Rao, S V; Unny, V K.P.; Shetiya, R S [Reactor Services and Maintenance Division, Bhabha Atomic Research Centre, Mumbai (India)

    1994-06-01

    In water treatment plants of nuclear reactors, type I strong base anion resins are extensively used in anion units along with strong acid cation resins in cation units for demineralisation of water. There is another kind of strong base anion resin called type II resin which is chemically slightly different from type I resin. Type II resins differ from the type I in that one of the methyl groups in the quaternary ammonium functional group of the latter, is replaced by an ethanol group. This results in lower basicity of the resin and hence, higher regeneration efficiency. However, the resin is not like a weak base resin in its properties since it is capable of removing silica from water, though not with the same efficiency as that of the type I strong base resin. Studies were carried out to compare the performance of presently used type I resins with that of type II resins supplied by local manufacturers to assess the suitability of the latter for use in the DM plants of Trombay reactors. This paper discusses the results of the studies. (author). 2 figs., 6 tabs.

  5. 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.)

  6. Radiation effects on ion-exchange resins. Part II. Gamma irradiation of Dowex 1

    International Nuclear Information System (INIS)

    Kazanjian, A.R.; Horrell, D.R.

    1975-01-01

    The effects were determined of gamma radiation on the anion exchange resin, Dowex 1. Part I on Dowex 50W was reported May 10, 1974. The exchange capacity (both strong and weak base), moisture content, radiolysis products, and physical deterioration of the resin were analyzed after irradiation with doses up to 6.9 x 10 8 rads. The resin capacity decreased approximately 50 percent after a radiation dose of 4 x 10 8 rads. Resin irradiated, when air dried in the nitrate form, showed more stability than resin irradiated in 7N nitric acid (HNO 3 ), which in turn showed more stability than resin irradiated when air dried in the chloride form. Radiation decreased the strong base capacity to a greater extent than the total capacity. The result indicates that some of the quarternary ammonium groups were transformed to secondary and tertiary amine groups that have weak base ion-exchange capability. (U.S.)

  7. 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

  8. Affinity purification of the voltage-sensitive sodium channel from electroplax with resins selective for sialic acid

    Energy Technology Data Exchange (ETDEWEB)

    James, W.M.; Emerick, M.C.; Agnew, W.S. (Yale Univ. School of medicine, New Haven, CT (USA))

    1989-07-11

    The voltage-sensitive sodium channel present in the eel (Electrophorus electricus) has an unusually high content of sialic acid, including {alpha}-(2{yields}8)-linked polysialic acid, not found in other electroplax membrane glycopeptides. Lectins from Limax flavus (LFA) and wheat germ (WGA) proved the most effective of 11 lectin resins tried. The most selective resin was prepared from IgM antibodies against Neisseria meningitidis {alpha}-(2{yields}8)-polysialic acid which were affinity purified and coupled to Sepharose 4B. The sodium channel was found to bind to WGA, LFA, and IgM resins and was readily eluted with the appropriate soluble carbohydrates. Experiments with LFA and IgM resins demonstrated binding and unbinding rates and displacement kinetics, which suggest highly specific binding at multiple sites on the sodium channel protein. In preparative-scale purification of protein previously fractionated by anion-exchange chromatography, without stabilizing TTX, high yields were reproducibly obtained. Further, when detergent extracts were prepared from electroplax membranes fractionated by low-speed sedimentation, a single step over the IgM resin provided a 70-fold purification, yielding specific activities of 3,200 pmol of ({sup 3}H)TTX-binding sites/mg of protein and a single polypeptide of {approximately}285,000 Da on SDS-acrylamide gels. No small peptides were observed after this 5-h isolation. The authors describe a cation-dependent stabilization with millimolar levels of monovalent and micromolar levels of divalent species.

  9. New anion-exchange resins for improved separations of nuclear materials

    International Nuclear Information System (INIS)

    Barr, M.E.; Bartsch, R.A.

    1998-01-01

    'The overall objective of this research is to develop a predictive capability which allows the facile design and implementation of multi-functionalized anion-exchange materials which selectively sorb metal complexes of interest from targeted process, waste, and environmental streams. The basic scientific issues addressed are actinide complex speciation along with modeling of the metal complex/functional-site interactions in order to determine optimal binding-site characteristics. The new ion-exchange resins interface the rapidly developing field of ion-specific chelating ligands with robust, commercial ion-exchange technology. Various Focus Areas and Crosscutting Programs have described needs that would be favorably impacted by the new materials: Efficient Separations and Processing; Plutonium; Plumes; Mixed Waste; High-Level Tank Waste. Sites within the DOE complex which would benefit from the improved anion-exchange technology include Hanford, INEL, Los Alamos, Oak Ridge, and Savannah River. As of April 1998, this report summarizes work after 1.6 years of a 3-year project. The authors technical approach combines empirical testing with theoretical modeling (applied in an iterative mode) in order to determine optimal binding-site characteristics. They determine actinide-complex speciation in specific media, then develop models for the metal complex/functional-site interactions Synthesis and evaluation of multi-functionalized extractants and ion-exchange materials that implement key features of the optimized binding site provide feedback to the modeling and design activities. Resin materials which actively facilitate the uptake of actinide complexes from solution should display both improved selectivity and kinetic properties. The implementation of the bifunctionality concept involves N-derivatization of pyridinium units from a base poly(4-vinylpyridine) resin with a second cationic site such that the two anion-exchange sites are linked by spacer arms of varying

  10. 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)

  11. Removal of both N-nitrosodimethylamine and trihalomethanes precursors in a single treatment using ion exchange resins.

    Science.gov (United States)

    Beita-Sandí, Wilson; Karanfil, Tanju

    2017-11-01

    Drinking water utilities are relying more than ever on water sources impacted by wastewater effluents. Disinfection/oxidation of these waters during water treatment may lead to the formation of several disinfection by-products, including the probable human carcinogen N-nitrosodimethylamine (NDMA) and the regulated trihalomethanes (THMs). In this study, the potential of ion exchange resins to control both NDMA and THMs precursors in a single treatment is presented. Two ion exchange resins were examined, a cation exchange resin (Plus) to target NDMA precursors and an anion exchange resin (MIEX) for THMs precursors control. We applied the resins, individually and combined, in the treatment of surface and wastewater effluent samples. The treatment with both resins removed simultaneously NDMA (43-85%) and THMs (39-65%) precursors. However, no removal of NDMA precursors was observed in the surface water with low initial NDMA FP (14 ng/L). The removals of NDMA FP and THMs FP with Plus and MIEX resins applied alone were (49-90%) and (41-69%), respectively. These results suggest no interaction between the resins, and thus the feasibility of effectively controlling NDMA and THMs precursors concomitantly. Additionally, the effects of the wastewater impact and the natural attenuation of precursors were studied. The results showed that neither the wastewater content nor the attenuation of the precursor affected the removals of NDMA and THMs precursors. Finally, experiments using a wastewater effluent sample showed that an increase in the calcium concentration resulted in a reduction in the removal of NDMA precursors of about 50%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. 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

  13. A novel approach to measure elemental concentrations in cation exchange resins using XRF-scanning technique, and its potential in water pollution studies

    Science.gov (United States)

    Huang, Jyh-Jaan; Lin, Sheng-Chi; Löwemark, Ludvig; Liou, Ya-Hsuan; Chang, Queenie; Chang, Tsun-Kuo; Wei, Kuo-Yen; Croudace, Ian W.

    2016-04-01

    X-ray fluorescence (XRF) core-scanning is a fast, and convenient technique to assess elemental variations for a wide variety of research topics. However, the XRF scanning counts are often considered a semi-quantitative measurement due to possible absorption or scattering caused by down core variability in physical properties. To overcome this problem and extend the applications of XRF-scanning to water pollution studies, we propose to use cation exchange resin (IR-120) as an "elemental carrier", and to analyze the resins using the Itrax-XRF core scanner. The use of resin minimizes the matrix effects during the measurements, and can be employed in the field in great numbers due to its low price. Therefore, the fast, and non-destructive XRF-scanning technique can provide a quick and economical method to analyze environmental pollution via absorption in the resin. Five standard resin samples were scanned by the Itrax-XRF core scanner at different exposure times (1 s, 5 s, 15 s, 30 s, 100 s) to allow the comparisons of scanning counts with the absolute concentrations. The regression lines and correlation coefficients of elements that are generally used in pollution studies (Ca, Ti, Cr, Ni, Cu, Zn, and Pb) were examined for the different exposure times. The result shows that within the test range (from few ppm to thousands ppm), the correlation coefficients are all higher than 0.97, even at the shortest exposure time (1 s). Therefore, we propose to use this method in the field to monitor for example sewage disposal events. The low price of resin, and fast, multi elements and precise XRF-scanning technique provide a viable, cost- and time-effective approach that allows large sample numbers to be processed. In this way, the properties and sources of wastewater pollution can be traced for the purpose of environmental monitoring and environmental forensics.

  14. Releasing Pattern of Applied Phosphorus and Distribution Change of Phosphorus Fractions in the Acid Upland Soils with Successive Resin Extraction

    Directory of Open Access Journals (Sweden)

    Arief Hartono

    2008-05-01

    Full Text Available The releasing pattern of applied P in the acid upland soils and the soil properties influencing the pattern were studied. Surface horizons of six acid upland soils from Sumatra, Java and Kalimantan were used in this study. The releasing pattern of applied P (300 mg P kg-1 of these soils were studied by successive resin extraction. P fractionation was conducted to evaluate which fractions released P to the soil solution after successive resin extraction. The cumulative of resin-Pinorganic (Pi release of soils was fitted to the first order kinetic. Regression analyses using factor scores obtained from the previous principal components analyses was applied to determine soil properties influencing P releasing pattern. The results suggested that the maximum P release was significantly (P < 0.05 increased by acidity plus 1.4 nm mineral-related factor (PC2 i.e. exchangeable Al and 1.4 nm minerals (smectite and vermiculite and decreased by oxide related factor (PC1 i.e. aluminum (Al plus 1/2 iron (Fe (by ammonium oxalate, crystalline Al and Fe oxides, cation exchange capacity, and clay content. P fractionation analysis after successive resin extraction showed that both labile and less labile in the form of NaHCO3-Pi and NaOH-Pi fractions, respectively, can be transformed into resin-Pi when in the most labile resin-Pi is depleted. Most of P released in high oxides soils were from NaOH-Pi fraction while in low oxides soils were from NaHCO3-Pi. P release from the former fraction resulted in the maximum P release lower than that of the latter one. When NaHCO3-Pi was high, NaOH-Pi was relatively more stable than NaHCO3-Pi despite resin-Pi removal. NaHCO3-Pi and NaOH-Pi are very important P fractions in replenishing resin-Pi in these acid upland soils.

  15. Cation exchange interaction between antibiotic ciprofloxacin and montmorillonite

    International Nuclear Information System (INIS)

    Wang, Chih-Jen; Li, Zhaohui; Jiang, Wei-Teh; Jean, Jiin-Shuh; Liu, Chia-Chuan

    2010-01-01

    Exploring the interactions between antibiotics and soils/minerals is of great importance in resolving their fate, transport, and elimination in the environment due to their frequent detection in wastewater, river water, sewage sludge and soils. This study focused on determining the adsorption properties and mechanisms of interaction between antibiotic ciprofloxacin and montmorillonite (SAz-1), a swelling dioctahedral mineral with Ca 2+ as the main interlayer cation. In acidic and neutral aqueous solutions, a stoichiometric exchange between ciprofloxacin and interlayer cations yielded an adsorption capacity as high as 330 mg/g, corresponding to 1.0 mmol/g. When solution pH was above its pK a2 (8.7), adsorption of ciprofloxacin was greatly reduced due to the net repulsion between the negatively charged clay surfaces and the ciprofloxacin anion. The uptake of ciprofloxacin expanded the basal spacing (d 001 ) of montmorillonite from 15.04 to 17.23 A near its adsorption capacity, confirming cation exchange within the interlayers in addition to surface adsorption. Fourier transform infrared results further suggested that the protonated amine group of ciprofloxacin in its cationic form was electrostatically attracted to negatively charged sites of clay surfaces, and that the carboxylic acid group was hydrogen bonded to the basal oxygen atoms of the silicate layers. The results indicate that montmorillonite is an effective sorbent to remove ciprofloxacin from water.

  16. Cation exchange interaction between antibiotic ciprofloxacin and montmorillonite

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chih-Jen [Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Department of Geosciences, National Taiwan University, Taipei 10617, Taiwan (China); Li, Zhaohui, E-mail: li@uwp.edu [Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Department of Geosciences, University of Wisconsin - Parkside, Kenosha, WI 53144 (United States); Jiang, Wei-Teh, E-mail: atwtj@mail.ncku.edu.tw [Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Jean, Jiin-Shuh; Liu, Chia-Chuan [Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China)

    2010-11-15

    Exploring the interactions between antibiotics and soils/minerals is of great importance in resolving their fate, transport, and elimination in the environment due to their frequent detection in wastewater, river water, sewage sludge and soils. This study focused on determining the adsorption properties and mechanisms of interaction between antibiotic ciprofloxacin and montmorillonite (SAz-1), a swelling dioctahedral mineral with Ca{sup 2+} as the main interlayer cation. In acidic and neutral aqueous solutions, a stoichiometric exchange between ciprofloxacin and interlayer cations yielded an adsorption capacity as high as 330 mg/g, corresponding to 1.0 mmol/g. When solution pH was above its pK{sub a2} (8.7), adsorption of ciprofloxacin was greatly reduced due to the net repulsion between the negatively charged clay surfaces and the ciprofloxacin anion. The uptake of ciprofloxacin expanded the basal spacing (d{sub 001}) of montmorillonite from 15.04 to 17.23 A near its adsorption capacity, confirming cation exchange within the interlayers in addition to surface adsorption. Fourier transform infrared results further suggested that the protonated amine group of ciprofloxacin in its cationic form was electrostatically attracted to negatively charged sites of clay surfaces, and that the carboxylic acid group was hydrogen bonded to the basal oxygen atoms of the silicate layers. The results indicate that montmorillonite is an effective sorbent to remove ciprofloxacin from water.

  17. The removal of toxic metals from liquid effluents by ion exchange resins. Part VI: Manganese(II/H+/Lewatit K2621

    Directory of Open Access Journals (Sweden)

    Francisco J. Alguacil

    2018-05-01

    Full Text Available In this sixth part of the series, Manganese(II was removed from aqueous solutions by the cationic exchange resin Lewatit K2621. The investigation was performed under various experimental conditions such as the stirring speed associated with the system, aqueous pH, temperature, resin dosage and the ionic strength of the solution. The performance of the resin against the loading of metals from metal-binary solutions as well as the removal of Manganese(II from the solutions using multiwalled carbon nanotubes and functionalized (carboxylic groups multiwalled carbon nanotubes, were also investigated. Experimental results fit well with the pseudo-first kinetic order model, whereas fit of the data show that at 20 °C the process responded well to the diffusion controlled model, and that at 60 °C, the system is controlled by the moving boundary model. Adsorption data is better related to the Freundlich isotherm. Elution of the Manganese(II loaded onto the resin was investigated using acidic (H2SO4 or HCl solutions.

  18. 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.)

  19. 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)

  20. 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.)

  1. 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.).

  2. The radiolytic and chemical degradation of organic ion exchange resins under alkaline conditions: effect on radionuclide speciation

    Energy Technology Data Exchange (ETDEWEB)

    Loon, L. van; Hummel, W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1995-10-01

    The formation of water soluble organic ligands by the radiolytic and chemical degradation of several ion exchange resins was investigated under conditions close to those of the near field of a cementitious repository. The most important degradation products were characterised and their role on radionuclide speciation evaluated thoroughly. Irradiation of strong acidic cation exchange resins (Powdex PCH and Lewatite S-100) resulted in the formation of mainly sulphate and dissolved organic carbon. A small part of the carbon (10-20%) could be identified as oxalate. The identity of the remainder is unknown. Complexation studies with Cu{sup 2+} and Ni{sup 2+} showed the presence of two ligands: oxalate and ligand X. Although ligand X could not be identified, it could be characterised by its concentration, a deprotonation constant and a complexation constant for the NiX complex. The influence of oxalate and ligand X on the speciation of radionuclides is examined in detail. For oxalate no significant influence on the speciation of radionuclides is expected. The stronger complexing ligand X may exert some influence depending on its concentration and the values of other parameters. These critical parameters are discussed and limiting values are evaluated. In absence of irradiation, no evidence for the formation of ligands was found. Irradiation of strong basic anion exchange resins (Powdex PAO and Lewatite M-500) resulted in the formation of mainly ammonia, amines and dissolved organic carbon. Up to 50% of the carbon could be identified as methyl-, dimethyl- and trimethylamine. Complexation studies with Eu{sup 3+} showed that the complexing capacity under near field conditions was negligible. The speciation of cations such as Ag, Ni, Cu and Pd can be influenced by the presence of amins. The strongest amine-complexes are formed with Pd and therefore, as an example, the aqueous Pd-ammonia system is examined in great detail. (author) 30 figs., 10 tabs., refs.

  3. Molten salt oxidation of ion-exchange resins doped with toxic metals and radioactive metal surrogates

    International Nuclear Information System (INIS)

    Yang, Hee-Chul; Cho, Yong-Jun; Yoo, Jae-Hyung; Kim, Joon-Hyung; Eun, Hee-Chul

    2005-01-01

    Ion-exchange resins doped with toxic metals and radioactive metal surrogates were test-burned in a bench-scale molten salt oxidation (MSO) reactor system. The purposes of this study are to confirm the destruction performance of the two-stage MSO reactor system for the organic ion-exchange resin and to obtain an understanding of the behavior of the fixed toxic metals and the sulfur in the cationic exchange resins. The destruction of the organics is very efficient in the primary reactor. The primarily destroyed products such as carbon monoxide are completely oxidized in the secondary MSO reactor. The overall collection of the sulfur and metals in the two-stage MSO reactor system appeared to be very efficient. Over 99.5% of all the fixed toxic metals (lead and cadmium) and radioactive metal surrogates (cesium, cobalt, strontium) remained in the MSO reactor bottom. Thermodynamic equilibrium calculations and the XRD patterns of the spent salt samples revealed that the collected metals existed in the form of each of their carbonates or oxides, which are non-volatile species at the MSO system operating conditions. (author)

  4. Use of Anion Exchange Resins for One-Step Processing of Algae from Harvest to Biofuel

    Directory of Open Access Journals (Sweden)

    Martin Poenie

    2012-07-01

    Full Text Available Some microalgae are particularly attractive as a renewable feedstock for biodiesel production due to their rapid growth, high content of triacylglycerols, and ability to be grown on non-arable land. Unfortunately, obtaining oil from algae is currently cost prohibitive in part due to the need to pump and process large volumes of dilute algal suspensions. In an effort to circumvent this problem, we have explored the use of anion exchange resins for simplifying the processing of algae to biofuel. Anion exchange resins can bind and accumulate the algal cells out of suspension to form a dewatered concentrate. Treatment of the resin-bound algae with sulfuric acid/methanol elutes the algae and regenerates the resin while converting algal lipids to biodiesel. Hydrophobic polymers can remove biodiesel from the sulfuric acid/methanol, allowing the transesterification reagent to be reused. We show that in situ transesterification of algal lipids can efficiently convert algal lipids to fatty acid methyl esters while allowing the resin and transesterification reagent to be recycled numerous times without loss of effectiveness.

  5. Test procedure for cation exchange chromatography

    International Nuclear Information System (INIS)

    Cooper, T.D.

    1994-01-01

    The purpose of this test plan is to demonstrate the synthesis of inorganic antimonate ion exchangers and compare their performance against the standard organic cation exchangers. Of particular interest is the degradation rate of both inorganic and organic cation exchangers. This degradation rate will be tracked by determining the ion exchange capacity and thermal stability as a function of time, radiation dose, and chemical reaction

  6. Concentrating cesium-137 from seawater using resorcinol-formaldehyde resin for radioecological monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Egorin, Andrei; Tokar, Eduard; Tutov, Mikhail; Avramenko, Valentin [Institute of Chemistry FEBRAS, Vladivostok (Russian Federation); Far Eastern Federal Univ., Vladivostok (Russian Federation); Palamarchuk, Marina; Marinin, Dmitry [Institute of Chemistry FEBRAS, Vladivostok (Russian Federation)

    2017-04-01

    A method of preconcentrating cesium-137 from seawater using a resorcinol-formaldehyde resin, which enables one to optimize the ecological monitoring procedure, has been suggested. Studies of sorption of cesium-137 from seawater by resorcinol-formaldehyde resin have been performed, and it has been demonstrated that the cation exchanger is characterized by high selectivity with respect to cesium-137. It was found that the selectivity depended on the temperature of resin solidification and the seawater pH value. The maximal value of the cesium-137 distribution coefficient is equal to 4.1-4.5 x 10{sup 3} cm{sup 3} g{sup -1}. Under dynamic conditions, the ion-exchange resin capacity is 310-910 bed volumes depending on the seawater pH, whereas the efficiency of cesium removal exceeds 95%. The removal of more than 95% of cesium-137 has been attained using 1-3 M solutions of nitric acid: here, the eluate volume was 8-8.4 bed volumes. Application of 3 M solution of nitric acid results in resin degradation with the release of gaseous products.

  7. New ion exchange resin designs and regeneration procedures yield improved performance for various condensate polishing applications

    International Nuclear Information System (INIS)

    Najmy, S.W.

    2002-01-01

    Condensate polishing is an application with many different design and operational aspects. The past decade has brought new challenges for improved water quality with respect to both soluble and insoluble contaminants. Nonetheless, the endeavors to understand the compositional complexities of the ion exchange resin bead and the convoluted dynamics of ion exchange chemistry and chemical engineering mechanisms occurring within the mixed bed condensate polisher have brought new ideas and expectations for ion exchange resin in deep-bed condensate polishers than ever before. The new products and procedures presented here are a collaboration of a great deal of effort on the part of researchers, consultants, system engineers, station chemists, lab technicians and others. The studies discussed in this paper unequivocally demonstrate the merits of: 1. A specially designed cation resin to achieve greater than 95% insoluble iron removal efficiency, 2. A less-separable mixed resin for improved control of reactor water sulfate in BWR primary cycles, 3. Applying increased levels of regeneration chemicals and retrofitting the service vessels with re-mixing capability to improve the operation of deep-bed condensate polishers in PWR secondary cycles. (authors)

  8. Tests of the use of cation exchange organic resins for the decontamination of radioactive aqueous effluents

    International Nuclear Information System (INIS)

    Bourdrez, Jean; Girault, Jacques; Wormser, Gerald

    1962-01-01

    The authors report tests performed in laboratory and results obtained during an investigation of the use of synthetic ion exchangers for the decontamination of radioactive effluents of moderate activity level and with a non neglectable salt loading. Resins are used under sodium form and regenerated after each fixing operation. Once decontaminated and free of its disturbing ions, the regenerating agent (NaCl) is used for several operations. The authors present the used resins, the treated effluents, describe the tests, and discuss the obtained results [fr

  9. Competition and enhancement effect in coremoval of atenolol and copper by an easily regenerative magnetic cation exchange resin.

    Science.gov (United States)

    Li, Qimeng; Wang, Zheng; Li, Qiang; Shuang, Chendong; Zhou, Qing; Li, Aimin; Gao, Canzhu

    2017-07-01

    This paper aimed to investigate the removal of combined Cu 2+ and atenolol (ATL) in aqueous solution by using a newly synthesized magnetic cation exchange resin (MCER) as the adsorbent. The MCER exhibited efficient removal performance in sole, binary, pre-loading and saline systems. The adsorption kinetics of Cu 2+ and ATL fitted both pseudo-first-order and pseudo-second order model, while better described by pseudo-second order model in binary system. In mixed Cu 2+ and ATL solution, the adsorption of ATL was suppressed due to direct competition of carboxylic groups, while Cu 2+ adsorption was enhanced because of the formation of surface complexes. This increasing in heterogeneity was demonstrated by adsorption isotherms, which were more suitable for Freundlich model in binary system, while better described by Langmuir model in sole system. As proved by FTIR and XPS spectra, both amino and hydroxyl groups of ATL could form complexes with Cu 2+ . Decomplexing-bridging interaction was elucidated as the leading mechanism in coremoval of Cu 2+ and ATL, which involved [Cu-ATL] decomplexing and newly created Cu- or ATL sites for additional bridging. For saline system, the resulting competition and enhancement effects in mixed solution were amplified with the addition of co-existing cations. Moreover, the MCER could be effectively regenerated by 0.01 M HCl solution and maintain high stability over 5 adsorption-desorption cycles, which render it great potential for practical applications. Copyright © 2017. Published by Elsevier Ltd.

  10. Cation exchange process for recovery of plutonium from laboratory solutions containing chloride

    International Nuclear Information System (INIS)

    Gray, L.W.

    1978-10-01

    A cation exchange technique was developed for the separation of plutonium from laboratory solutions containing either Pu(III) or Pu(III)--Pu(IV) mixtures in acidic solutions containing chloride ions. The procedure consists of adjusting the acid concentration to less than one molar and adjusting the valence of the plutonium ion to the (III) state, if necessary. The adjusted solution is fed to a cation exchange column and washed with distilled water to remove residual chlorides from the column. Plutonium is then eluted from the column with 5M nitric acid containing 0.34M sulfamic acid. This procedure was used to separate plutonium from 1.2M chloride solution on a production-scale column. Typical plutonium recovery was 99.97%, while greater than 96% of the original chloride was rejected

  11. Inversion of the calcium isotope separation at an ion exchanger resin by variation of the LiCl electrolyte concentration

    International Nuclear Information System (INIS)

    Heumann, K.G.; Kloeppel, H.; Sigl, G.

    1982-01-01

    The calcium isotope separation at a strongly acidic exchanger resin as a function of the concentration of a LiCl solution is investigated in column experiments. Whereas an enrichment of the heavier calcium isotopes in the solution phase is found with a 3 M LiCl solution, an inverse effect is obtained with 8 M and 12 M LiCl solutions. The separation effect epsilon for the 12 M solution is found to be the highest calcium enrichment in a system without a complexing agent. The results are compared with those for other electrolyte solutions and can be explained by the anion/cation interactions. (orig.)

  12. The influence of plutonium concentration and solution flow rate on the effective capacity of macroporous anion exchange resin

    International Nuclear Information System (INIS)

    Marsh, S.F.; Gallegos, T.D.

    1987-07-01

    The principal aqueous process used to recover and purify plutonium at the Los Alamos Plutonium Facility is anion exchange in nitric acid. Previous studies with gel-type anion exchange resin have shown an inverse relationship between plutonium concentration in the feed solution and the optimum flow rate for this process. Because gel-type resin has been replaced with macroporous resin at Los Alamos, the relationship between plutonium concentration and solution flow rate was reexamined with the selected Lewatit MP-500-FK resin using solutions of plutonium in nitric acid and in nitric acid with high levels of added nitrate salts. Our results with this resin differ significantly from previous data obtained with gel-type resin. Flow-rate variation from 10 to 80 liters per hour had essentially no effect on the measured quantities of plutonium sorbed by the macroporous resin. However, the effect of plutonium concentration in the feed solutions was pronounced, as feed solutions that contained the highest concentrations of plutonium also produced the highest resin loadings. The most notable effect of high concentrations of dissolved nitrate salts in these solutions was an increased resin capacity for plutonium at low flow rates. 16 refs., 7 figs., 2 tabs

  13. 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

  14. Fixation of metallic sulfosalicylate complexes on an anionic exchange resin

    International Nuclear Information System (INIS)

    Cahuzac, S.

    1969-06-01

    Since sulfosalicylate ions have acid-base properties, sulfosalicylate complexes have an apparent stability which varies with the ph. As a result, the fixation of sulfo-salicylates on an anionic exchange resin depends on the ph of the solution in equilibrium with the resin. This research has been aimed at studying the influence of the ph on the fixation on an anionic exchange resin (Dowex 1 x 4) of sulfosalicylate anions on the one hand, and of metallic sulfosalicylate complexes on the other hand. In the first part of this work, a determination has been made, by frontal analysis of the distribution of sulfosalicylate ions in the resin according to the total sulfosalicylate I concentration in the aqueous solution in equilibrium with the resin. The exchange constants of these ions between the resin and the solution have been calculated. In the second part, a study has been made of the fixation of anionic sulfosalicylate complexes of Fe(III), Al(III), Cr(III), Cu(II), Ni(II), Co(II), Zn(II), Mn(II), Cd(II), Fe(II) and UO 2 2+ . By measuring the partition coefficients of these different elements between the resin and the solution it has been possible to give interpretation for the modes of fixation of the metallic ions, and to calculate their exchange constant between the resin and the solution. The relationship has been established for each metallic element studied, between its partition coefficient, the ph and the total concentration of the complexing agent in solution. Such a relationship makes it possible to predict, for given conditions, the nature of the species in solution and in the resin, as well as the partition coefficient of a metallic, element. Finally, in the third part of the work, use has been made of results obtained previously, to carry out some separations (Ni 2+ - Co 2+ ; Ni 2+ - Co 2+ - Cu 2+ ; UO 2 2+ - Fe 3+ ; UO 2 2+ - Cr 3+ ; UO 2 2+ - Cu 2+ ; UO 2 2+ - Ni 2+ ; UO 2 2+ - Co 2+ ; UO 2 2+ - Mn 2+ and UO 2 2+ - Cd 2+ ), as well as the purification

  15. Thermochemical stability of Soviet macroporous sulfonated cation-exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Rukhlyada, N.N.; Plotnikova, V.P.; Roginskaya, B.S.; Znamenskii, Yu.P.; Zavodovskaya, A.S.; Dobrova, E.I.

    1988-10-20

    The purpose of this work was to study the influence of macroporosity on the thermochemical stability of sulfonated cation-exchangers. The investigations were carried out on commercial macroporous sulfonated cation-exchangers based on styrene-divinylbenzene copolymers. Study of the thermochemical stability of macroporous sulfonated cation-exchangers in dilute hydrogen peroxide solutions showed that the type of macroporosity has virtually no influence on their stability. The determining factor in thermal stability of macroporous cation-exchangers, as of the gel type, is the degree of cross-linking of the polymer matrix. The capacity loss of macroporous cation-exchangers during oxidative thermolysis is caused by destruction of the macromolecular skeleton and elution of fragments of polar chains containing sulfo groups into the solution.

  16. An investigation of the applicability of the new ion exchange resin, Reillex{trademark}-HPQ, in ATW separations. Milestone 4, Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ashley, K.R.; Ball, J.; Grissom, M.; Williamson, M.; Cobb, S.; Young, D.; Wu, Yen-Yuan J.

    1993-09-07

    The investigations with the anion exchange resin Reillex{trademark}-HPQ is continuing along several different paths. The topics of current investigations that are reported here are: The sorption behavior of chromium(VI) on Reillex{trademark}-HPQ from nitric acid solutions and from sodium hydroxide/sodium nitrate solutions; sorption behavior of F{sup {minus}} on Reillex{trademark}-HPQ resin in acidic sodium nitrate solution; sorption behavior of Cl{sup {minus}} on Reillex{trademark}-HPQ resin in acidic sodium nitrate solution; sorption behavior of Br{sup {minus}} on Reillex{trademark}-HPQ resin in acidic sodium nitrate solution; and the Honors thesis by one of the students is attached as Appendix II (on ion exchange properties of a new macroperous resin using bromide as the model ion in aqueous nitrate solutions).

  17. Corrosion of steel drums containing immobilized ion exchange-resins and incineration ashes

    International Nuclear Information System (INIS)

    Marotta, F.; Schulz Rodriguez, F.M.; Farina, Silvia B.; Duffo, Gustavo S.

    2009-01-01

    The Argentine Atomic Energy Commission (CNEA) is responsible for developing the management nuclear waste disposal programme. This programme contemplates the design and construction of a facility for the final disposal of intermediate-level radioactive wastes. The proposed model is a near-surface monolithic repository similar to those in operation in El Cabril, Spain. The design of this type of repository is based on the use of multiple, independent and redundant barriers. The intermediate radioactive waste consists mostly in spent ionic exchange resins and filters from the nuclear power plants, research reactors and radioisotopes production facilities. The spent resins, as well as the incineration ashes, have to be immobilized before being stored to improve leach resistance of waste matrix and to maintain mechanical stability for safety requirements. Generally, cementation processes have been used as immobilization techniques for economical reasons as well as for being a simple operation. The immobilized resins and incineration ashes are thus contained in steel drums that, in turn, can undergo corrosion depending on the ionic content of the matrix. This work is a part of a systematic study of the corrosion susceptibility of steel drums in contact with immobilized cemented exchange-resins with different types and contents of aggressive species and incineration ashes. To this purpose, a special type of specimen was manufactured to simulate the cemented waste in the drum. The evolution of the corrosion potential and the corrosion current density of the steel, as well as the electrical resistivity of the matrix are being monitored along time. The aggressive species studied were chloride ions (the main ionic species present in nature) and sulphate ions (produced during the radiolysis process of the cationic exchange-resins after cementation). Preliminary results show the strong effect of chloride on the corrosion susceptibility of the steel. Monitoring will continue for

  18. Formation of Zirconium Hydrophosphate Nanoparticles and Their Effect on Sorption of Uranyl Cations

    Science.gov (United States)

    Perlova, Nataliya; Dzyazko, Yuliya; Perlova, Olga; Palchik, Alexey; Sazonova, Valentina

    2017-03-01

    Organic-inorganic ion-exchangers were obtained by incorporation of zirconium hydrophosphate into gel-like strongly acidic polymer matrix by means of precipitation from the solution of zirconium oxychloride with phosphoric acid. The approach for purposeful control of a size of the incorporated particles has been developed based on Ostwald-Freundich equation. This equation has been adapted for precipitation in ion exchange materials. Both single nanoparticles (2-20 nm) and their aggregates were found in the polymer. Regulation of salt or acid concentration allows us to decrease size of the aggregates approximately in 10 times. Smaller particles are formed in the resin, which possess lower exchange capacity. Sorption of U(VI) cations from the solution containing also hydrochloride acid was studied. Exchange capacity of the composites is ≈2 times higher in comparison with the pristine resin. The organic-inorganic sorbents show higher sorption rate despite chemical interaction of sorbed ions with functional groups of the inorganic constituent: the models of reaction of pseudo-first or pseudo-second order can be applied. In general, decreasing in size of incorporated particles provides acceleration of ion exchange. The composites can be regenerated completely, this gives a possibility of their multiple use.

  19. Mathematical simulation of equilibria in the Pr(3) chloride-iminodiacetic acid - cation exchange resin system

    Energy Technology Data Exchange (ETDEWEB)

    Kupriyanova, G.N.; Krivenko, S.V.; Martynenko, L.I.; Evseev, A.M.; Spitsyn, V.I. (Moskovskij Gosudarstvennyj Univ. (USSR))

    1982-01-01

    Multiresponse adequate mathematical model is constructed that describes the composition of phases in the complex ion exchange system r.e.e. (PrCl/sub 3/)-complexon (iminodiacetic acid)-cationite-H/sub 2/O-KOH. The model is constructed on the basis of the law of acting masses in combination with equations of material balance and electroneutrality equations. The considerable effect on the state of the sorption system of metal complexonates is proved. The account of absorption of praseodymium iminodiacetates is necessary for complete description of the system and control of chromatographic process.

  20. Research advances in adsorption treatment of cesium and cobalt in waste liquid of nuclear power plants by ion exchange resin

    International Nuclear Information System (INIS)

    Liu Dan; Wang Xin; Liu Jiean; Zhu Laiye; Chen Bin; Weng Minghui

    2014-01-01

    Liquid radwaste is unavoidably produced during the operation of nuclear power plants (NPP). With the development of China's nuclear power, much more attention will be paid to the impact of NPP construction on water environment. Radionuclides are the main targets for adsorption treatment of NPP liquid radwaste. Thereinto, cesium and cobalt are typical cationic ones. Currently, ion exchange process is widely used in liquid radwaste treatment system (WLS) of NPP, wherein resin plays a key role. The paper reviewed the research progress on adsorption of cesium and cobalt existed in NPP liquid radwaste using ion exchange resin. (authors)

  1. Purification of degraded TBP solvent using macroreticular anion exchange resin

    International Nuclear Information System (INIS)

    Kartha, P.K.S.; Kutty, P.V.E.; Janaradanan, C.; Ramanujam, A.; Dhumwad, R.K.

    1989-01-01

    Tri-n-butyl phosphate (TBP) diluted with a suitable diluent is commonly used for solvent extraction in Purex process for the recovery of uranium and plutonium from irradiated nuclear fuels. This solvent gets degraded due to various factors, the main degradation product being dibutyl phosphoric acid (HDBP). A solvent cleanup step is generally incorporated in the process for removing the degradation products from the used solvent. A liquid-liquid cleanup system using sodium carbonate or sodium hydroxide solution is routinely used. Considering certain advantages, like the possibility of loading the resin almost to saturation capacity and the subsequent disposal of the spent resin by incineration and the feasibility of adopting it to the process, a liquid-solid system has been tried as an alternate method, employing various available macroreticular anion exchange resins in OH - form for the sorption of HDBP from TBP. After standardizing the various conditions for the satisfactory removal of HDBP from TBP using synthetic mixtures, resins were tested with process solvent in batch contacts. The parameters studied were (1) capacity of different resins for HDBP sorption (2) influence of acidity, uranium and HDBP on the sorption behaviour of the latter (3) removal of fission products from the solvent by the resin and (4) regeneration and recycling of the resin. (author). 2 figs., 13 tabs., 17 refs

  2. Properties of sulfonated cation-exchangers made from petroleum asphaltites

    International Nuclear Information System (INIS)

    Pokonova, Yu.V.; Pol'kin, G.B.; Proskuryakov, V.A.

    1982-01-01

    The use of ion-exchangers in radiochemical technology is accompanied by changes of their properties under the influence of ionizing radiation. The rate of development of these processes depends on the nature and structure of the matrix and on the nature and amount of ionic groups. We have proposed a method of synthesis of ion-exchangers resistant to γ radiation from petroleum asphaltites. Continuing these investigations, we prepared cation-exchangers by sulfonation of a mixture of petroleum asphaltites and acid asphalt. An investigation of their radiation resistance is described in this paper

  3. Influence of differences in resin-matrix structure on ion-exchange adsorption of trace amounts of Ag(I), Co(II) and Cr(III)

    International Nuclear Information System (INIS)

    Matsuzuru, Hideo; Wadachi, Yoshiki

    1975-01-01

    The influence of differences in resin-matrix structure on the ion-exchange adsorption of trace amounts of Ag(I), Co(II) and Cr(III) was studied by using both macroreticular and gel-type resins. The results indicate that the rate-determining step of the exchange mechanism of these ions is film diffusion under conditions of finite volume and at an ionic strengh of 1x10 -4 . The diffusion coefficient decreases with increasing size of the hydrated ions - in the order Dsub(Ag)>Dsub(Co)>Dsub(Cr). It may be said that the faster rate of exchange in the macroreticular resin is due to the larger surface area and pore size of this resin. Also, in a column system - as opposed to batch operation, it is assumed that the rate-determining step of the exchange reaction is film diffusion. With both resins, the kinetic coefficient β decreases in the order: βsub(Ag)>βsub(Co)>βsub(Cr). For the same linear velocity, a higher β-value is obtained with the macroreticular than with the gel-type resin. Consequently, a higher separating efficiency may be expected from the macroreticular resin for concentrating and separating trace amounts of cations from aqueous solution. (auth.)

  4. Synthesis and chemical modification of polymeric resins for the treatment of cations and aromatic hydrocarbons in produced oily water; Sintese de modificacao quimica de resina polimerica e aplicacao na remocao de cations e hidrocarbonetos aromaticos presentes em agua produzida

    Energy Technology Data Exchange (ETDEWEB)

    Aversa, Thiago M.; Rodrigues, Monique F.; Vieira, Helida V.P.; Queiros, Yure G.C.; Lucas, Elizabete F. [Universidade Federal do Rio de Janeiro, Instituto de Macromoleculas, Lab. de Macromoleculas e Coloides na Industria do Petroleo, Rio de Janeiro, RJ (Brazil)], e-mail: thiagoaversa@ima.ufrj.br

    2011-07-01

    The use of chemically modified resins in oily water treatment process is not very developed yet. Because of this, this work suggests to study the styrene and divinylbenzene sulfonation effect on oil and grease, aniline and calcium removal from the water. The aniline, oils and greases belong to a class of toxic organic compounds, with the Brazilian maximum limits established for disposal in CONAMA 393/2007, while the calcium ions belong to the group of cations of alkaline earth metals which improve hardness to the water, may cause fouling as carbonates and sulfates form. By using sulfonated resins in oily water treatment it is possible to remove not only oils and greases but also calcium and aniline. These kinds of polar compounds are removed because of the cation exchange capacity of resin. (author)

  5. Chromatographic studies of the lanthanide element separation for the americium/curium large scale separation using ion exchange resins

    International Nuclear Information System (INIS)

    Ginisty, Claude.

    1981-06-01

    The Am/Cm large scale separations, operated by chromatography with the use of ion exchange resins, are described by numerous publications. The bibliographic studies allow to retain the followed points: use of sulfonate cationic resins, development by elution with the α-hydroxyisobutyric acid, column loadings between 1 and 30% of the capacity, possibility to use no radioactive lanthanides prior to actinides for trial purposes. The optimisation of such a process is the major part of this thesis. This point is realised by introducing a new definition for the resolution, for non symmetrical elution peaks, and a measure of this dissymmetry by introducing a shape factor F. For the separation itself and for the pressure drop in the column, the influence of the following parameters are studied: composition of the elution solution (concentration and pH), column temperature (20 to 90 0 C), resin size (9 to 27 μm), rate flow of mobile phase (70 ml.cm -2 .mn -1 ), column length and diameter. Symmetrical elution peaks may be obtained, even with a 27% loading. Elution conditions may be modified during the separation process in order to have the best recovery for the two components (1,3 [fr

  6. Infrared spectroscopy and thermal analysis of prepared cation exchangers from cellulosic materials

    International Nuclear Information System (INIS)

    Nada, A.M.A.; EI-Sherief, S.; Nasr, A.; Kamel, M.

    2005-01-01

    Different cation exchangers were prepared by incorporation of phosphate and sulfate groups into acid or alkali treated wood pulp. The molecular structure of these cation exchangers were followed by infrared spectroscopy and thermal degradation analysis technique. From infrared spectra, a new bands are seen at 1200 and 980 cm-1 in phosphorylated wood pulp due to the formation of C-O-P bond. Another bands were seen at 1400, 1200 and 980 cm-1 in phospho sulfonated wood pulp due to the formation of CO- P and C-O-S bonds. Also, it is seen from infrared spectra that the crystallinity index for acid treated wood pulp has a higher value than untreated and alkali treated wood pulp. On the other hand, the acid treated and phosphorylated acid treated wood pulp have a higher activation energy than untreated and phosphorylated alkali treated wood pulp

  7. Spray drying of bead resins: feasibility tests

    International Nuclear Information System (INIS)

    Gay, R.L.; Grantham, L.F.; Jones, L.J.

    1984-01-01

    Rockwell International has developed a volume reduction system for low-level reactor wastes based on drying the wastes in a heated-air spray dryer. The drying of slurries of sodium sulfate, boric acid, and powdered ion exchange resins was demonstrated in previous tests. The drying of bead ion exchange resins can be especially difficult due to the relatively large size of bead resins (about 500 to 800 microns) and their natural affinity for water. This water becomes part of the pore structure of the resins and normally comprises 50 t 60 wt % of the resin weight. A 76-cm-diameter spray dryer was used for feasibility tests of spray drying of cation and anion bead resins. These resins were fed to the dryer in the as-received form (similar to dewatered resins) and as slurries. A dry, free-flowing product was produced in all the tests. The volume of the spray-dried product was one-half to one-third the volume of the as-received material. An economic analysis was made of the potential cost savings that can be achieved using the Rockwel spray dryer system. In-plant costs, transportation costs, and burial costs of spray-dried resins were compared to similar costs for disposal of dewatered resins. A typical utility producing 170 m 3 (6,000 ft 3 ) per year of dewatered resins can save $600,000 to $700,000 per year using this volume reduction system

  8. Study of the retention of radionuclides by ion-exchange resins contained in the circuits of a Pressurized Water Reactor; Etude de la retention des radionucleides dans les resines echangeuses d'ions des circuits d'une centrale nucleaire a eau sous pression

    Energy Technology Data Exchange (ETDEWEB)

    Gressier, F.

    2008-11-15

    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{sup 2+}, Ni{sup 2+}, Cs{sup +} and Li{sup +} 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)

  9. SOLVENT EFFECTS ON THE HYDRATION OF CYCLOHEXENE CATALYZED BY A STRONG ACID ION-EXCHANGE RESIN .3. EFFECT OF SULFOLANE ON THE EQUILIBRIUM CONVERSION

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    The liquid-phase hydration of cyclohexene, a pseudo-first-order reversible reaction catalyzed by a strong acid ion-exchange resin, was investigated in solvent mixtures of water and sulfolane. Macroporous Amberlite XE 307 was used because of its superior catalytic activity. Chemical equilibrium

  10. Adsorption of copper from the sulphate solution of low copper contents using the cationic resin Amberlite IR 120

    International Nuclear Information System (INIS)

    Jha, Manis Kumar; Nghiem Van Nguyen; Lee, Jae-chun; Jeong, Jinki; Yoo, Jae-Min

    2009-01-01

    In view of the increasing importance of the waste processing and recycling to meet the strict environmental regulations, the present investigation reports an adsorption process using the cationic exchanger Amberlite IR 120 for the recovery/removal of copper from the synthetic sulphate solution containing copper ≤0.7 mg/mL similar to the CMP waste effluent of electronic industry. Various process parameters, viz. contact time, solution pH, resin dose, and acid concentration of eluant were investigated for the adsorption of copper from the effluents. The 99.99% copper was found to be adsorbed from the sulphate solution containing copper 0.3-0.7 mg/mL of solution (feed pH 5) at A/R ratio 100 and eq. pH 2.5 in contact time 14 min. The mechanism for the adsorption of copper was found to follow Langmuir isotherm and second order rate. From the loaded organic, copper was eluted effectively by 1.8 M sulphuric acid at A/R ratio 25. The raffinate obtained after the recovery copper could be disposed safely without affecting the environment.

  11. Bacterial growth on ion exchange resin - investigations with a strong cationic exchanger. Pt. 3. Disinfection with peracetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Flemming, H.C.

    1984-12-01

    The suitability of peracetic acid (PAA) for the disinfection of ion exchangers was investigated. 0.02% PAA is suitable for satisfactory disinfection. In this way corrosive effects are strongly reduced. Ca/sup 2+/-ions seem to protect the bacteria, therefore the disinfection should be done with the Na/sup +/-form. The disinfection has no remanent effect and therefore is not suitable for preventing bacterial aftergrowth during off-periods. A combination of silver and disinfectant can accomplish this, until a new, silver-tolerant microflora has evolved. In this case the use of 0.02% PAA is imperative, because higher concentrations will dissolve the silver. As a principle the effectiveness of disinfection procedure should be monitored bacteriologically.

  12. Gamma radiolysis and post-irradiation leaching of ion exchange resins

    International Nuclear Information System (INIS)

    Traboulsi, A.

    2012-01-01

    The knowledge of the behavior under irradiation and in presence of water of Ion Exchange Resins (IER) is very necessary to predict their impact on the environment during the storage phase and in a possible deep geological disposal. The IER studied are the MB400 mixed bed resin and its 'pure' anionic and cationic components. The experimental strategy used in this work was based on the use of chemometric tools permitting to estimate the effect of the irradiation atmosphere, the dose rate, the absorbed dose and the leaching temperature. The gaseous and water-soluble radiolysis products were analyzed by gas Mass Spectrometry (MS) and Ion Chromatography (IC). The IER generated principally H 2 g, CO 2 g and amines for which quantities depended of the resin nature and the irradiation conditions. The analysis of solid irradiated resins was investigated by Fourier Transformed Infrared (FTIR) and Nuclear Magnetic Resonance ( 13 C NMR) techniques. The last ones revealed structural modifications of the IER solid matrix in function of the experimental conditions. Their behavior in presence of water was studied during 143 days by characterization of the organic matter released after their post-irradiation leaching. The kinetics showed that all the water-soluble components were releasing at the first contact with water. The Total Organic Carbon (TOC) quantity released depends, according to the resin nature, either on the dose, either on the irradiation atmosphere. The dose rate has no effect on the degradation and the leaching of the MB400 resin, which behaved differently than its pure components. (author) [fr

  13. The regeneration test of the secondary loop condensate polishing mixed bed resin in Qinshan NPP

    International Nuclear Information System (INIS)

    Xu Meijing; Dong Liming

    1995-12-01

    There are four condensate polishing mixed beds in the water chemical treatment plant of Qinshan NPP. 2125 kg of D001-TR type cation exchange resin, 2000 kg of D201-TR type anion exchange resin, and 375 kg of S-TR type inert resin are filled into each mixed bed. The bed height of resin is 1.2 m and the volume is about 2.7 m 3 . In order to regenerate the exhausted resin out of the bed, the pre-designed condensate polishing mixed bed regeneration process was used to regenerate the first exhausted resin. After the resin was scrubbed and separated, cation resin and anion resin were respectively regenerated, rinsed to resume the exchange capability of the resin. The regenerated mixed bed is able to keep higher efficiency for condensate polishing. The outlet water quality and the resin service-life are able to meet the design requirements or more favorable than that. During the test, some main cations and anions in the blow-off water at each procedure were analyzed. The analyzed results were used to make pre-designed regeneration process better. The test results proved that pre-designed process is reasonable and effective. (6 refs., 6 figs., 7 tabs.)

  14. Performance Variation of Spent Resin in Mixed Bed From Water Purifying System of Xi'an Pulse Reactor

    International Nuclear Information System (INIS)

    Li Hua; Ma Yan; Xiao Yan; Liu Yueheng; Yang Yongqing

    2010-01-01

    Detailed physical and chemical characteristic analysis was performed on the spent cation and anion resins in the mixed bed from Xi'an Pulse Reactor water purifying system.The exchange performance variations of used resins and the contributions from different factors to the variation were discussed.Based on the obtained information of the impurities in the used resin, the contamination state of the water in the Xi'an Pulse Reactor water pool, the corrosion state of the structural material in the reactor was presented. The spent anion resin almost completely losses its exchange performance,while the remaining exchange capacity in the spent cation resin is still high.The radiation field from the reactor operation contributes little to the degradation of the performance of the resins. The exchange capacity loss of the spent anion resin is due to the exchange of its active groups into abundant carbonate and a certain amount of organics. The impurity amount in the anion and cation exchange resins is low,which suggests(that) the water in the Xi'an Pulse Reactor water pool is little contaminated. A certain extent of corrosion is occurred on the structural material in the swimming pool of the reactor. The results provide important referential data for the operational safety of the water purifying system of similar research reactor. (authors)

  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 on properties of cation-exchange membranes containing sulfonate groups

    International Nuclear Information System (INIS)

    Zu Jianhua; Wu Minghong; Qiu Shilong; Yao Side; Ye Yin

    2004-01-01

    Strong acid cation-exchange membranes were obtained by irradiation grafting of acrylic acid (AA) and sodium styrene sulfonate (SSS) onto high-density polyethylene (HDPE). Thermal and chemical stability of the cation-exchange membranes was investigated. The effectiveness of sulfonate-containing films was conformed in inducing high resistance to oxidative degradation. Thermal stability of the grafted HDPE was weaker than HDPE as detected by TGA analyzing technique. Char residue by TGA of the grafted HDPE is greater than that of HDPE. It shows that the branch chains including -SO 3 Na and -COOH was grafted onto the backbone of HDPE, and thus give a catalytic impetus to the charing. Crystallinity of the grafted membranes decreased with increasing grafting yield of the membrane samples. It is supposed that the decreased crystallinity is due to collective effects of the inherent crystallinity dilution by the amorphous grafted chains and disruption of spherulitic crystallites of the HDPE component

  17. Catalytic oxidative pyrolysis of spent organic ion exchange resins from nuclear power plants

    International Nuclear Information System (INIS)

    Sathi Sasidharan, N.; Deshingkar, D.S.; Wattal, P.K.; Shirsat, A.N.; Bharadwaj, S.R.

    2005-08-01

    The spent IX resins from nuclear power reactors are highly active solid wastes generated during operations of nuclear reactors. Catalytic oxidative pyrolysis of these resins can lead to high volume reduction of these wastes. Low temperature pyrolysis of transition metal ion loaded IX resins in presence of nitrogen was carried out in order to optimize catalyst composition to achieve maximum weight reduction. Thermo gravimetric analysis of the pyrolysis residues was carried out in presence of air in order to compare the oxidative characteristics of transition metal oxide catalysts. Copper along with iron, chromium and nickel present in the spent IX resins gave the most efficient catalyst combination for catalytic and oxidative pyrolysis of the residues. During low temperature catalytic pyrolysis, 137 Cesium volatility was estimated to be around 0.01% from cationic resins and around 0.1% from anionic resins. During oxidative pyrolysis at 700 degC, nearly 10 to 40% of 137 Cesium was found to be released to off gases depending upon type of resin and catalyst loaded on to it. The oxidation of pyrolytic residues at 700 degC gave weight reduction of 15% for cationic resins and 93% for anionic resins. Catalytic oxidative pyrolysis is attractive for reducing weight and volume of spent cationic resins from PHWRs and VVERs. (author)

  18. 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

  19. Treatment by absorbers of oil contaminated process waters. Ion exchange resins and filtration

    International Nuclear Information System (INIS)

    La Gamma, Ana M.; Becquart, Elena T.; Chocron, Mauricio; Ambrosioni, P.M.; Schoenbrod, B.

    2003-01-01

    Pressurized Heavy Water Reactors have a system devoted to the purification and upgrading of the collected heavy water leaks. The purification train is fed with different degradation ratios (D 2 O/H 2 O) activities and impurities. The water is distilled in a packed bed column filled with a mesh type packing. With the purpose of minimizing the column stack corrosion, the water is pretreated in a train consisting on an activated charcoal bed-strong cationic-anionic resin and a final polishing mixed bed resin. Traces of oils are retained by the charcoal bed but some compounds extracted by the aqueous phase are suspected to be responsible for the resins fouling or precursors of potentially aggressive agents inside the distillation column. In the present work, the identification, evaluation of alternatives for the retention like dead end and cross flow micro filtration, adsorption and ion exchange were tested and the results compared to the original products present in the water upgrading purification train. (author)

  20. The removal of toxic metals from liquid effluents by ion exchange resins. Part IV: Chromium(III)/H+ /Lewatit SP112

    International Nuclear Information System (INIS)

    Alguacil, F.J.

    2017-01-01

    This investigation presented results on the removal of chromium(III), from aqueous solution in the 0-5 pH range, using Lewatit SP112 cationic exchange resin. Several aspects affecting the ion exchange process were evaluated, including: the influence of the stirring speed, temperature, pH of the solution, resin dosage and aqueous ionic strength. The selectivity of the system was tested against the presence of other metals in the aqueous solution, whereas the removal of chromium(III) from solutions was compared with results obtained using multiwalled carbon nanotubes as adsorbents. From the batch experimental data, best fit of the results is obtained with the Langmuir model, whereas the ion exchange process is best explained by the pseudo-second order model, moreover, experimental data responded well to the film-diffusion controlled model. Elution of the chromium(III) loaded into the resin is well accomplished by the use of sodium hydroxide solutions. [es

  1. 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.)

  2. Synthesis and characterization of an N-(2-hydroxyethyl)-ethylenediaminetriacetic acid resin

    International Nuclear Information System (INIS)

    Lai, Y.F.

    1977-10-01

    A chelating ion-exchange resin with N-(2-hydroxyethyl)ethylene-diaminetriacetic acid (HEDTA) used as the ligand chemically bonded to XAD-4 by an ester linkage, HEDTA-4, was synthesized. It is stable under normal experimental conditions with the liquid chromatograph. The structure of the resin was confirmed by an infrared spectrum, and by potentiometric titrations. The capacity of the resin was also obtained by potentiometric titration and by a nitrogen analysis. The resin was used to pack a column of 5 mm internal diameter and 5 cm long. The effect of pH on the retention of different metal ions on the resin was studied. It was found that the resin was most selective for chromium(III), copper(II), lead(II), mercury(II), uranium(VI), zirconium(IV) and zinc(II) at a pH of less than 3. Furthermore, the resin proves to be functioning with a chelating mechanism rather than ion-exchange, and it can concentrate trace metal ions in the presence of a large excess of calcium and magnesium. This makes the resin potentially useful for purifying and analyzing drinking water

  3. Immobilisation in cement of ion exchange resins arising from the purification of reagents used for the decontamination of reactor circuits

    International Nuclear Information System (INIS)

    Donoghue, S.J.; Howard, C.G.; Lee, D.J.

    1987-06-01

    An account of the annual decontaminations undertaken on the SGHWR at Winfrith is given with reasons for changing from Citrox reagents to LOMI plus the effects of using nitric acid permanganate solution as a preoxidising agent. Safe disposal of these reagents after use is a problem concerning many water cooled reactor operators. A brief review of the various methods of disposal is given. The proposed method of disposing of LOMI wastes generated at Winfrith is to remove the activity onto ion exchange resins then immobilize them in a cement matrix. Duolite C225 (a cross linked polystyrene with sulphonic acid functional groups) has been identified as a suitable ion exchanger. Duolite C225 in the sodium form can be successfully immobilised in blended cement systems. The formulation which appears acceptable is manufactured from a 9 to 1 blend of Blast Furnace Slag and Ordinary Portland Cement, containing 40% ion exchange resin by weight, in the form of a slurry. The product has adequate strength for handling and shows little dimensional change with time. Experiments show that above 50% waste loading the product becomes unstable and its strength is unacceptably low. Changes in the metal cation have shown little effect on the properties of the product. Increasing the waste loading appears to have little effect on the hydration rate of the product. Preliminary calculations show that a volume reduction factor of 4 is obtained by taking the active LOMI effluent, removing the activity onto the Duolite C225 and then immobilising in cement. (author)

  4. A maturation method of uranium content in resins with acid dissolution

    International Nuclear Information System (INIS)

    Liu Yang

    2010-01-01

    Acid dissolution method is that with intensively oxidation acid to decompose ion exchanging resins and dissolving U and Fe ion in water, then menstruate the U content by titration. Comparing with our current method of filtering wash, acid dissolution menstruation U can get more accurate result and take less time, use more simple device. (authors)

  5. Anion-exchange resin-based desulfurization process. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sheth, A C; Dharmapurikar, R; Strevel, S D

    1994-01-01

    The following investigations were performed: (1) batch mode screening of eleven(11) commercially available resins and selection of three candidate resins for further evaluation in a fixed-bed setup. (2) Process variables study using three candidate resins in the fixed-bed setup and selection of the ``best`` resin for process economics development. (3) Exhaustion efficiency and solution concentration were found to be inversely related necessitating a trade-off between the resin cost versus the cost of evaporation/concentration of ensuing effluents. (4) Higher concentration of the HCO{sub 3}{sup {minus}} form of active sites over less active CO{sub 3}{sup 2{minus}} form of sites in the resin was believed to be the main reason for the observed increase in the equilibrium capacity of the resin at an elevated static CO{sub 2}-pressure. This Increase in capacity was found to level off around 80--120 psig range. The increase in CO{sub 2}-pressure, however, did not appear to affect the overall ion-exchange kinetics. (5) In the fixed-bed mode, the solution concentration was found to affect the equilibrium capacity of candidate resins. Their relationship was well satisfied by the Langmuir type non-linear equilibrium isotherm. Alternatively, the effect of solution concentration on overall ion-exchange kinetics varied from resin to resin. (6) Product inhibition effect on the resin was observed as an initial increase followed by a significant decrease in the resin`s equilibrium capacity for SO{sub 4}{sup 2{minus}} as the HCO{sub 3}{sup {minus}}/SO{sub 4}{sup 2{minus}} molar ratio in the solution was increased from 0 to 1.0. This ratio, however, did not affect the overall ion-exchange kinetics.

  6. A review of the development of resins for use in hydrometallurgy

    International Nuclear Information System (INIS)

    Green, B.R.

    1985-01-01

    Commercial resins, including cation exchangers, anion exchangers, and complexing resins, that may be suitable for use in the extraction of metals are reviewed. Areas where further research is required are considered, and potential applications that are of particular interest to the Council for Mineral Technology (Mintek), involving the recovery of uranium, gold, and the base metals, are described. Commercial resins and experimental resins developed at Mintek are evaluated, and the results are reviewed

  7. Generation of radioisotopes

    International Nuclear Information System (INIS)

    Panek-Finda, H.

    1984-01-01

    A method of producing radioisotopes for radiopharmaceutical applications is claimed. A physiological solution is used to elute a radioactive daughter isotope from a fission-produced parent isotope adsorbed on an adsorbent. The eluate containing the daughter isotope is purified with a cation-exchange material. In separate claims: the parent isotope is molybdenum-99; aluminium oxide which contains fully or partly hydrated manganese dioxide is used as the adsorbent for the parent isotope; a resin is used as the cation-exchange material; a strongly acid cation-exchange resin which has been neutralized is used as a resin; and a strongly acid cation-exchange resin which has been converted into the Na + , K + or NH 4 + form is used as a resin; an isotope generator system is also claimed

  8. Solidification of ion exchange resins saturated with Na+ ions: Comparison of matrices based on Portland and blast furnace slag cement

    International Nuclear Information System (INIS)

    Lafond, E.; Cau dit Coumes, C.; Gauffinet, S.; Chartier, D.; Stefan, L.; Le Bescop, P.

    2017-01-01

    This work is devoted to the conditioning of ion exchange resins used to decontaminate radioactive effluents. Calcium silicate cements may have a good potential to encapsulate spent resins. However, certain combinations of cement and resins produce a strong expansion of the final product, possibly leading to its full disintegration. The focus is placed on the understanding of the behaviour of cationic resins in the Na + form in Portland or blast furnace slag (CEM III/C) cement pastes. During hydration of the Portland cement paste, the pore solution exhibits a decrease in its osmotic pressure, which causes a transient expansion of small magnitude of the resins. At 20 °C, this expansion takes place just after setting in a poorly consolidated material and is sufficient to induce cracks. In the CEM III/C paste, swelling of the resins also occurs, but before the end of setting, and induces limited stress in the matrix which is still plastic. - Highlights: • Solidification of cationic resins in the Na + -form is investigated. • Portland and blast furnace slag cements are compared. • Deleterious expansion is observed with Portland cement only. • Resin swelling is due to a decrease in the osmotic pressure of the pore solution. • The consolidation rate of the matrix is a key parameter to prevent damage.

  9. In vitro adsorption of oxalic acid and glyoxylic acid onto activated charcoal, resins and hydrous zirconium oxide

    NARCIS (Netherlands)

    Scholtens, R.; Scholten, J.; de Koning, H. W.; Tijssen, J.; ten Hoopen, H. W.; Olthuis, F. M.; Feijen, J.

    1982-01-01

    Patients suffering from primary hyperoxaluria show elevated plasma concentrations of oxalic acid and glyoxylic acid. The in vitro adsorption of these compounds into activated charcoal, a series of neutral and ion exchange resins and onto hydrous zirconium oxide has been investigated. Hydrous

  10. 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)

  11. 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

  12. Uses of complexone III and ion exchange resins in colorimetric determination with o-phenanthroline of Fe traces in uranium compounds

    International Nuclear Information System (INIS)

    Fernandez Cellini, R.; Ruiz Sanchez, F.

    1956-01-01

    The determination of small quantities of iron using o-phenanthroline, assumes the elimination of some cations interference by means of pH control before the formation of a coloured complex. We have eluded that difficulty by the connected action of complexones III and ion exchange. the previous forms quelate with the iron (III) with a stability constant high enough to permit the pass of an iron solution through a cation resin column without being fixed which never occurs with the interferer cations. Mercury is the only element with a similar stability, but it has been eliminated previously. (Author) 16 refs

  13. Rapid radiochemical ion-exchange separation of iodine from tellurium: a novel radioiodine-132 generator

    Energy Technology Data Exchange (ETDEWEB)

    Abrao, A

    1975-01-01

    Tellurium ions form a soluble cationic complex with thiourea in acid medium. The cationic tellurium-thiourea species is strongly absorbed on a cationic ion exchanger. The retention of tellurium on the resin enables many interesting separation schemes for tellurium from various ions. With special interest, the separation of iodine from tellurium was studied. An efficient and convenient iodine-132 generator is described, in which the radio-iodine is eluted with water or 9 g/1 NaCl, when desired.

  14. Solvent Extraction of Tungsten(VI) from Moderate Hydrochloric Acid Solutions with LIX 63

    Energy Technology Data Exchange (ETDEWEB)

    Truong, Hoai Thanh; Lee, Man Seung [Mokpo National University, Jeollanamdo (Korea, Republic of); Kim, Yong Hwan [Incheon Technology Service Centre, Incheon (Korea, Republic of)

    2017-06-15

    The solvent extraction of tungsten(VI) from hydrochloric acid solutions using 5,8-diethyl-7-hydroxydodecan-6-one oxime (LIX 63) was analyzed in solutions having an initial pH range from 2 to 5, by varying the concentration of metal and extractant. In our experimental range, the cationic exchange reaction as well as the solvation reaction occurred simultaneously. The cation exchange reaction was identified by applying a slope analysis method to the extraction data. The existence of cationic tungsten(VI) species was confirmed by ion exchange experiments with Diphonix resin at pH 3. Further study is needed to identify the nature of this tungsten cationic species.

  15. 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.

  16. 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

  17. SOLVENT EFFECTS ON THE HYDRATION OF CYCLOHEXENE CATALYZED BY A STRONG ACID ION-EXCHANGE RESIN .2. EFFECT OF SULFOLANE ON THE REACTION-KINETICS

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    The kinetics of the' hydration of cyclohexene, catalyzed by a strong acid ion-exchange resin, have been studied in a packed bed reactor at temperatures between 353 and 413 K and a pressure of 20 bar. The kinetic rate constants were measured as a function of temperature and solvent composition (0-90

  18. 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

  19. 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

  20. Solidification of ion exchange resins saturated with Na{sup +} ions: Comparison of matrices based on Portland and blast furnace slag cement

    Energy Technology Data Exchange (ETDEWEB)

    Lafond, E. [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Cau dit Coumes, C., E-mail: celine.cau-dit-coumes@cea.fr [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Gauffinet, S. [Laboratoire Interdisciplinaire Carnot de Bourgogne UMR 6303 CNRS-Université de Bourgogne, Dijon, France, 9 Av Alain Savary, BP 47870, 21078 Dijon cedex (France); Chartier, D. [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Stefan, L. [AREVA, Back End Business Group, Dismantling & Services, 1 Place Jean Millier, 92084 Paris La Défense (France); Le Bescop, P. [CEA, DEN, DPC, SECR, F-91192 Gif-sur-Yvette (France)

    2017-01-15

    This work is devoted to the conditioning of ion exchange resins used to decontaminate radioactive effluents. Calcium silicate cements may have a good potential to encapsulate spent resins. However, certain combinations of cement and resins produce a strong expansion of the final product, possibly leading to its full disintegration. The focus is placed on the understanding of the behaviour of cationic resins in the Na{sup +} form in Portland or blast furnace slag (CEM III/C) cement pastes. During hydration of the Portland cement paste, the pore solution exhibits a decrease in its osmotic pressure, which causes a transient expansion of small magnitude of the resins. At 20 °C, this expansion takes place just after setting in a poorly consolidated material and is sufficient to induce cracks. In the CEM III/C paste, swelling of the resins also occurs, but before the end of setting, and induces limited stress in the matrix which is still plastic. - Highlights: • Solidification of cationic resins in the Na{sup +}-form is investigated. • Portland and blast furnace slag cements are compared. • Deleterious expansion is observed with Portland cement only. • Resin swelling is due to a decrease in the osmotic pressure of the pore solution. • The consolidation rate of the matrix is a key parameter to prevent damage.

  1. The reactivity of anion-exchange resins by applying OT-for-OH exchange reaction in the equilibrium state

    International Nuclear Information System (INIS)

    Kano, Naoki; Nihei, Makoto; Imaizumi, Hiroshi

    1996-01-01

    In order to reveal the behavior of hydroxyl group in isotope exchange reaction, OT-for-OH exchange reaction between each anion-exchange resin (OH - form) and tritiated water (abbreviated as HTO water below) was observed at 80degC under the equilibrium. Anion-exchange resins used were Amberlite IRA-400, IRA-410 (both strongly basic), and IRA-94S (weakly basic). It can be thought that an HTO molecule dissociates into H + +OT - (or T + +OH - ). The activity of each resin based on OT-for-OH exchange reaction was measured with a liquid scintillation counter. From the above-mentioned, the following five were found. Isotope exchange reaction as 'atomic group' occurred between the OH group in each anion-exchange resin and the OT group in HTO water. The reactivity of strongly basic anion-exchange resin is larger than that of weakly basic one. The ratio of the reactivity of these resins can roughly be expressed as follows: (IRA-410): (IRA-400): (IRA-94S)=42: 7: 1. The degree of OT-for-OH exchange reaction may be smaller than that of T-for-H exchange reaction. The method used and results obtained in this work may be helpful to obtain the data for the prevention of T-contamination, especially to obtain the data from certain atomic groups including T. (author)

  2. Electron-beam curing of epoxy resins: effect of alcohols on cationic ...

    Indian Academy of Sciences (India)

    Unknown

    Electron-beam (e-beam) induced polymerization of epoxy resins proceeds via cationic mechanism in presence of suitable ... generate ionic species, free radicals, and/or molecules in .... bisphenol A) and the effect of presence of different OH.

  3. Ion exchange treatment of rinse water generated in the galvanizing process.

    Science.gov (United States)

    Marañón, Elena; Fernández, Yolanda; Castrillón, Leonor

    2005-01-01

    A study was conducted of the viability of using the cationic exchange resins Amberlite IR-120 and Lewatit SP-112 to treat rinse water generated in the galvanizing process as well as acidic wastewater containing zinc (Zn) and iron (Fe). Solutions containing either 100 mg/L of Zn at pH 5.6 (rinse water) or Fe and Zn at concentrations of 320 and 200 mg/L at pH 1.5 (acidic water), respectively, were percolated through packed beds until the resins were exhausted. Breakthrough capacities obtained ranged between 1.1 and 1.5 meq metal/mL resin. The elution of metal and the regeneration of resins were performed with hydrochloric acid. The influence of the flowrate used during the loading stage was also studied, with 0.5 bed volumes/min (3.2 cm/min) found to be the optimum flowrate.

  4. A basic study for the boron thermal regeneration system using anion exchange resins

    International Nuclear Information System (INIS)

    Frantiesek, P.; Kotaka, Masahiro; Okamoto, Makoto; Kakihana, Hidetake.

    1979-01-01

    For the boron thermal regeneration system (BTRS), the basic characteristics of commercial anion exchange resin have been investigated on the swelling characteristics, absorption, desorption and temperature coefficient of exchange capacity for boric acid. The equilibrium capacity increases as decrease of temperature and depends strongly on the degrees of cross linking having a maximum point at about 7% of DVB. The temperature coefficient of equilibrium capacity of boric acid is also a function of the concentration of external solution and of the cross linking having a maximum point around 7% of DVB. (author)

  5. A rapid radiochemical ion-exchange separation of iodine from tellurium: a novel radioiodine-132 generator

    International Nuclear Information System (INIS)

    Abrao, A.

    1975-01-01

    Tellurium ions form a soluble cationic complex with thiourea in acid medium. The cationic tellurium-thiourea species is strongly absorbed on a cationic ion exchanger. The retention of tellurium on the resin enables many interesting separation schemes for tellurium from various ions. With special interest, the separation of iodine from tellurium was studied. An efficient and convenient iodine-132 generator is described, in which the radio-iodine is eluted with water or 9 g/1 NaCL, when desired

  6. Ion-exchange-resin-catalyzed adamantylation of phenol derivatives with adamantanols: Developing a clean process for synthesis of 2-(1-adamantyl-4-bromophenol, a key intermediate of adapalene

    Directory of Open Access Journals (Sweden)

    Nan Wang

    2012-02-01

    Full Text Available A clean process has been developed for the synthesis of 2-adamantylphenol derivatives through adamantylation of substituted phenols with adamantanols catalyzed by commercially available and recyclable ion-exchange sulfonic acid resin in acetic acid. The sole byproduct of the adamantylation reaction, namely water, could be converted into the solvent acetic acid by addition of a slight excess of acetic anhydride during the work-up procedure, making the process waste-free except for regeneration of the ion-exchange resin, and facilitating the recycling of the resin catalyst. The ion-exchange sulfonic acid resin catalyst could be readily recycled by filtration and directly reused at least ten times without a significant loss of activity. The key intermediate of adapalene, 2-(1-adamantyl-4-bromophenol, could be produced by means of this waste-free process.

  7. Cation-anion imbalance: Effect on PWR steam generator crevice pH - an acidic case study

    International Nuclear Information System (INIS)

    Paine, J.P.N.; Shoemaker, C.E.

    1990-01-01

    Ion exchange resins remove cations more efficiently than anions from feedwater to nuclear steam generators. The resulting imbalance is made up in the feedwater train by ammonia additions. In the steam generator, the ammonia is quickly flashed off leaving acid ions for an ionic balance. The almost pure water concentrates by boiling in heated crevices, in theory, to levels permitted by the available superheat (difference between primary and secondary temperatures). The concentrations may reach an ionic strength of greater than 20 molal on the hot leg, depending on bulk water concentration, time of steady state operation, fouling of crevice locations, and solubilities of the various salts, i.e., kinetic as well as thermodynamic considerations. While some of the acid species distill out of the crevices, more may be trapped by corrosive reactions. In the paper, theoretical crevice pH is calculated by MULTEQ. An attempt is made to relate pH to steady state operation time and crevice fouling. The data are normalized to be independent of bulk water concentration. Neutralization of the acid is explored

  8. Cation Exchange Water Softeners

    Science.gov (United States)

    WaterSense released a notice of intent to develop a specification for cation exchange water softeners. The program has made the decision not to move forward with a spec at this time, but is making this information available.

  9. Development of Highly Nano-Dispersed NiO/GDC Catalysts from Ion Exchange Resin Templates

    Directory of Open Access Journals (Sweden)

    Angel Caravaca

    2017-11-01

    Full Text Available Novel NiO/GDC (Gadolinium-doped Ceria cermet catalysts were developed by the Weak Acid Resin (WAR method using an ion exchange resin template. In addition, the specific surface area of these tunable materials was enhanced by NiO partial dissolution in aqueous acid solution. The whole procedure highly improved the micro-structural properties of these materials compared to previous studies. Catalysts with high metal loadings (≥10%, small Ni nanoparticles (<10 nm, and high specific surface areas (>70 m2/g were achieved. These properties are promising for catalytic applications such as methane steam reforming for H2 production.

  10. Adsorption of Monobutyl Phthalate from Aqueous Phase onto Two Macroporous Anion-Exchange Resins

    Directory of Open Access Journals (Sweden)

    Zhengwen Xu

    2014-01-01

    Full Text Available As new emerging pollutants, phthalic acid monoesters (PAMs pose potential ecological and human health risks. In the present study, adsorption performance of monobutyl phthalate (MBP onto two macroporous base anion-exchange resins (D-201 and D-301 was discussed. It was found that the adsorption isotherms were best fitted by the Langmuir equation while the adsorption kinetics were well described by pseudo-first-order model. Analyses of sorption isotherms and thermodynamics proved that the adsorption mechanisms for DBP onto D-201 were ion exchange. However, the obtained enthalpy values indicate that the sorption process of MBP onto D-301 is physical adsorption. The equilibrium adsorption capacities and adsorption rates of DBP on two different resins increased with the increasing temperature of the solution. D-301 exhibited a higher adsorption capacity of MBP than D-201. These results proved that D-301, as an effective sorbent, can be used to remove phthalic acid monoesters from aqueous solution.

  11. 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.

  12. Separation and determination of arsenic species in water by selective exchange and hybrid resins

    Energy Technology Data Exchange (ETDEWEB)

    Issa, Nureddin Ben [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia); Rajakovic-Ognjanovic, Vladana N. [Faculty of Civil Engineering, University of Belgrade, Bulevar Kralja Aleksandra 73, Belgrade (Serbia); Marinkovic, Aleksandar D. [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia); Rajakovic, Ljubinka V., E-mail: ljubinka@tmf.bg.ac.rs [Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, Belgrade (Serbia)

    2011-11-07

    Highlights: {yields} A simple and efficient method for separation and determination of arsenic species. {yields} A new hybrid resin HY-AgCl is effective for iAs and oAs analytical separation. {yields} SBAE resin was convenient for the separation of As(III) from As(V) and oAs species. {yields} HY-Fe resin was convenient for the separation of DMAs(V). - Abstract: A simple and efficient method for separation and determination of inorganic arsenic (iAs) and organic arsenic (oAs) in drinking, natural and wastewater was developed. If arsenic is present in water prevailing forms are inorganic acids of As(III) and As(V). oAs can be found in traces as monomethylarsenic acid, MMA(V), and dimethylarsenic acid, DMAs(V). Three types of resins: a strong base anion exchange (SBAE) and two hybrid (HY) resins: HY-Fe and HY-AgCl, based on the activity of hydrated iron oxides and a silver chloride were investigated. It was found that the sorption processes (ion exchange, adsorption and chemisorptions) of arsenic species on SBAE (ion exchange) and HY resins depend on pH values of water. The quantitative separation of molecular and ionic forms of iAs and oAs was achieved by SBAE and pH adjustment, the molecular form of As(III) that exists in the water at pH <8.0 was not bonded with SBAE, which was convenient for direct determination of As(III) concentration in the effluent. HY-Fe resin retained all arsenic species except DMAs(V), which makes possible direct measurements of this specie in the effluent. HY-AgCl resin retained all iAs which was convenient for direct determination of oAs species concentration in the effluent. The selective bonding of arsenic species on three types of resins makes possible the development of the procedure for measuring and calculation of all arsenic species in water. In order to determine capacity of resins the preliminary investigations were performed in batch system and fixed bed flow system. Resin capacities were calculated according to breakthrough

  13. Synthesis of biodiesel from pongamia oil using heterogeneous ion-exchange resin catalyst.

    Science.gov (United States)

    Jaya, N; Selvan, B Karpanai; Vennison, S John

    2015-11-01

    Biodiesel is a clean-burning renewable substitute fuel for petroleum. Biodiesel could be effectively produced by transesterification reaction of triglycerides of vegetable oils with short-chain alcohols in the presence of homogeneous or heterogeneous catalysts. Conventionally, biodiesel manufacturing processes employ strong acids or bases as catalysts. But, separation of the catalyst and the by-product glycerol from the product ester is too expensive to justify the product use as an automobile fuel. Hence heterogeneous catalysts are preferred. In this study, transesterification of pongamia oil with ethanol was performed using a solid ion-exchange resin catalyst. It is a macro porous strongly basic anion exchange resin. The process parameters affecting the ethyl ester yield were investigated. The reaction conditions were optimized for the maximum yield of fatty acid ethyl ester (FAEE) of pongamia oil. The properties of FAEE were compared with accepted standards of biodiesel. Engine performance was also studied with pongamia oil diesel blend and engine emission characteristics were observed. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Separation of hemicellulose-derived saccharides from wood hydrolysate by lime and ion exchange resin.

    Science.gov (United States)

    Wang, Xiaojun; Zhuang, Jingshun; Fu, Yingjuan; Tian, Guoyu; Wang, Zhaojiang; Qin, Menghua

    2016-04-01

    A combined process of lime treatment and mixed bed ion exchange was proposed to separate hemicellulose-derived saccharides (HDS) from prehydrolysis liquor (PHL) of lignocellulose as value added products. The optimization of lime treatment achieved up to 44.2% removal of non-saccharide organic compounds (NSOC), mainly colloidal substances, with negligible HDS degradation at 0.5% lime level and subsequent neutralization by phosphoric acid. The residual NSOC and calcium ions in lime-treated PHL were eliminated by mixed bed ion exchange. The breakthrough curves of HDS and NSOC showed selective retention toward NSOC, leading to 75% HDS recovery with 95% purity at 17 bed volumes of exchange capacity. In addition, macroporous resin showed higher exchange capacity than gel resin as indicated by the triple processing volume. The remarkable selectivity of the combined process suggested the feasibility for HDS separation from PHL. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Ion exchange-based treatment of "6"0Co contaminated well-water for storing γ irradiation source

    International Nuclear Information System (INIS)

    Bi Meng; Miao Shilin; Zhang Xiaolu; Zhang Youjiu

    2014-01-01

    Objective: To select an efficient ion exchange resin to purify the "6"0Co contaminated well-water for storing radioactive source and to ensure the radioactivity of "6"0Co in treated well-water below 10 Bq/L. Methods: The radioactivity of "6"0Co in the water samples was measured by using the potassium cobaltinitrite coprecipitation-β counting method. The treatment efficiencies of two different ion exchange resins for the simulated "6"0Co-bearing waste water were compared to select a better one to dispose of the "6"0Co contaminated well-water. Results: The treatment efficiency of MBD-15-SC mixed ion exchange resin was about 5.8 times higher than ZGCNR50 strong-acid cation exchange resin. The radioactivity of "6"0Co in the contaminated well-water could be reduced from 4.16 × 10"5 Bq/L to 1.16 Bq/L by two-stage sorption of MBD-15-SC mixed ion exchange resin. Conclusions: Using several times of two-stage MBD-15-SC mixed ion exchange resin could effectively purify the "6"0Co contaminated well-water. The quality of the treated well-water could meet the sewage discharge standards. (authors)

  16. 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.

  17. Forging Colloidal Nanostructures via Cation Exchange Reactions.

    Science.gov (United States)

    De Trizio, Luca; Manna, Liberato

    2016-09-28

    Among the various postsynthesis treatments of colloidal nanocrystals that have been developed to date, transformations by cation exchange have recently emerged as an extremely versatile tool that has given access to a wide variety of materials and nanostructures. One notable example in this direction is represented by partial cation exchange, by which preformed nanocrystals can be either transformed to alloy nanocrystals or to various types of nanoheterostructures possessing core/shell, segmented, or striped architectures. In this review, we provide an up to date overview of the complex colloidal nanostructures that could be prepared so far by cation exchange. At the same time, the review gives an account of the fundamental thermodynamic and kinetic parameters governing these types of reactions, as they are currently understood, and outlines the main open issues and possible future developments in the field.

  18. Forging Colloidal Nanostructures via Cation Exchange Reactions

    Science.gov (United States)

    2016-01-01

    Among the various postsynthesis treatments of colloidal nanocrystals that have been developed to date, transformations by cation exchange have recently emerged as an extremely versatile tool that has given access to a wide variety of materials and nanostructures. One notable example in this direction is represented by partial cation exchange, by which preformed nanocrystals can be either transformed to alloy nanocrystals or to various types of nanoheterostructures possessing core/shell, segmented, or striped architectures. In this review, we provide an up to date overview of the complex colloidal nanostructures that could be prepared so far by cation exchange. At the same time, the review gives an account of the fundamental thermodynamic and kinetic parameters governing these types of reactions, as they are currently understood, and outlines the main open issues and possible future developments in the field. PMID:26891471

  19. Immobilization in cement of ion exchange resins from Spanish nuclear reactors

    International Nuclear Information System (INIS)

    Huebra, A.G. de la; Murillo, R.; Ortiz, S.J.

    1990-01-01

    Ion exchange materials used at nuclear power plants can be immobilized in cements less expensive than polymer matrices. Cement solidification of spent ion exchange resins shows swelling and cracking troubles (during setting time, or of storage). The objective of this study was to select the types of cement that produce the best quality on immobilization of three kinds of resins and to set up cement formulations containing the maximum possible loading of resin. Four cements were selected to carried out the study. After a study of hydration-dehydration phenomena of ion exchange resins, a systematic work has been carried out on immobilization. Tests were performed to study compressive strength and underwater stability by changing water/cement ratio and resin/cement ratio. Mixtures made with water, cement and resin only were loaded with 10% by weight dry resin. Mixtures with higher loadings show poor workability. Tests were carried out by adding organic plasticizers and silica products to improve waste loading. Plasticizers reduced water demand and silica products permit the use of more water. Leaching tests have been performed at 40 O C. In conclusion Blast Furnace Slag is the best cement for immobilization of ion exchange resin both bead and powdered form for mechanical strength, stability and leaching

  20. Solidification of ion exchange resins saturated with Na+ ions: Comparison of matrices based on Portland and blast furnace slag cement

    Science.gov (United States)

    Lafond, E.; Cau dit Coumes, C.; Gauffinet, S.; Chartier, D.; Stefan, L.; Le Bescop, P.

    2017-01-01

    This work is devoted to the conditioning of ion exchange resins used to decontaminate radioactive effluents. Calcium silicate cements may have a good potential to encapsulate spent resins. However, certain combinations of cement and resins produce a strong expansion of the final product, possibly leading to its full disintegration. The focus is placed on the understanding of the behaviour of cationic resins in the Na+ form in Portland or blast furnace slag (CEM III/C) cement pastes. During hydration of the Portland cement paste, the pore solution exhibits a decrease in its osmotic pressure, which causes a transient expansion of small magnitude of the resins. At 20 °C, this expansion takes place just after setting in a poorly consolidated material and is sufficient to induce cracks. In the CEM III/C paste, swelling of the resins also occurs, but before the end of setting, and induces limited stress in the matrix which is still plastic.

  1. 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.

  2. HIGH ASPECT RATIO ION EXCHANGE RESIN BED - HYDRAULIC RESULTS FOR SPERICAL RESIN BEADS

    International Nuclear Information System (INIS)

    Duignan, M; Charles Nash, C; Timothy Punch, T

    2007-01-01

    A principal role of the DOE Savannah River Site is to safely dispose of a large volume of liquid nuclear waste held in many storage tanks. An in-tank ion exchange unit is being considered for cesium removal to accelerate waste processing. This unit is planned to have a relatively high bed height to diameter ratio (10:1). Complicating the design is the need to cool the ion exchange media; therefore, the ion exchange column will have a central cooling core making the flow path annular. To separate cesium from waste the media being considered is made of resorcinol formaldehyde resin deposited on spherical plastic beads and is a substitute for a previously tested resin made of crystalline silicotitanate. This spherical media not only has an advantage of being mechanically robust, but, unlike its predecessor, it is also reusable, that is, loaded cesium can be removed through elution and regeneration. Resin regeneration leads to more efficient operation and less spent resin waste, but its hydraulic performance in the planned ion exchange column was unknown. Moreover, the recycling process of this spherical resorcinol formaldehyde causes its volume to significantly shrink and swell. To determine the spherical media's hydraulic demand a linearly scaled column was designed and tested. The waste simulant used was prototypic of the wastes' viscosity and density. This paper discusses the hydraulic performance of the media that will be used to assist in the design of a full-scale unit

  3. Use of a phenolic-carboxylic acid cation resin in the treatment of low-level liquid waste at Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    Chilton, J.M.

    1981-09-01

    The loading capacity of CS-100 resin, using plant waste as feed, was found to be significantly reduced after 20 loading-elution cycles; one-fourth or less of the original capacity was retained after 30 cycles. No important differences were noted between an untreated column and a column that had been reconverted to the sodium form in the regeneration step. Omission of the sodium regeneration could not be adopted as a routine procedure because it produced a packing effect in the plant beds; however, reconversion to the sodium form is now achieved by using a stoichiometric amount of caustic rather than a 100% excess, as was previous practice. Since the distribution coefficients for calcium and strontium are about six times greater than that for cesium, no loss of 90 Sr would be expected while 137 Cs is loading. Laboratory results obtained by using plant conditions and feed indicate that a typical bed would remove 96% of 90 Sr in the feed. Cobalt-60 is generally the greatest contributor to the radioactivity of the plant effluent. Laboratory tests indicate that this 60 Co is present as a mixture of a soluble anionic complex and insoluble colloids. The anionic complex could be removed by placing an anion exchange column in the effluent from the CS-100 resin bed. In studies of the dynamics of loading on CS-100 resin, the contact time in plant operation (3 to 4 min per column volume) was found to be more than adequate to obtain the desired results. Effects of flow velocity were not investigated. Data from a series of laboratory experiments show that CS-100 resin can be eluted satisfactorily with 0.5 to 1.0 M formic or acetic acid, although a larger volume is required than for elution with 0.5 M nitric acid

  4. Treatment of spent ion-exchange resins for storage and disposal

    International Nuclear Information System (INIS)

    1985-01-01

    This report describes the experience gained by different countries on storage of spent ion exchange resins, immobilization of them into various matrices and the development of new methods in decomposition and solidification of spent resins. The report contains all the results of the Coordinated Research Programme together with additional data available from countries not participating in this programme. A review of practical industrial experience in treating spent ion exchange resins is given in the annex

  5. Microscopic theory of cation exchange in CdSe nanocrystals.

    Science.gov (United States)

    Ott, Florian D; Spiegel, Leo L; Norris, David J; Erwin, Steven C

    2014-10-10

    Although poorly understood, cation-exchange reactions are increasingly used to dope or transform colloidal semiconductor nanocrystals (quantum dots). We use density-functional theory and kinetic Monte Carlo simulations to develop a microscopic theory that explains structural, optical, and electronic changes observed experimentally in Ag-cation-exchanged CdSe nanocrystals. We find that Coulomb interactions, both between ionized impurities and with the polarized nanocrystal surface, play a key role in cation exchange. Our theory also resolves several experimental puzzles related to photoluminescence and electrical behavior in CdSe nanocrystals doped with Ag.

  6. Separation of metal ions by anion exchange in mixtures of hydrochloric acid and hydrofluoric acid

    International Nuclear Information System (INIS)

    Faris, J.P.

    1978-12-01

    Distribution coefficients were determined for the adsorption of more than 40 elements on anion-exchange resins from mixtures of HCl (0.1 to 12M) and HF (0.1-8M). Two resins, Dowex 1 x 10, 200 to 400 mesh and Dowex 1 x 4, 100 to 200 mesh, were used. Distribution coefficients were also determined for the adsorption of many elements on both resins from 0.1 to 12M HCl and 0.1 to 12M HF. Anion exchange in the presence of HF was found useful for separating impurities from various materials for their subsequent determination, and specific procedures used in our spectrochemical laboratory for this purpose are outlined. The results of a literature search on the use of anion exchange in hydrofluoric acid and fluoride-containing media are presented in an extensive bibliography. 404 references, 9 tables

  7. 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

  8. Recover of some rare earth elements from leach liquor of the Saghand uranium ore using combined precipitation and cation exchange methods

    International Nuclear Information System (INIS)

    Khanchi, A. R.; Rafati, H.; Rezvaniyanzadeh, M. R.

    2008-01-01

    In this research work, the recovery and separation of La(III), Ce(III), Sm(III), Dy(III) and Nd(III) from Saghand uranium ore have been studied by precipitation and ion-exchange chromatography methods using Dowex 50 W-X 8 cation exchanger. At first, some preliminary and preconcentration experiments such as comminution, sieve analysis, gravity table and electrostatic in preconcentration of lanthanides were performed. Then, acidic digesting and leaching procedure were used. The results of experiments showed that rare earth elements, along with interfering ions such as Al(III), Fe(III), Mg(II) and Mn(II) present in the leach liquor solution. The investigation of separation process by precipitation method revealed that precipitation and then fast separation using centrifugal technique had the best results in the elimination of interference elements. In order to separate the lanthanides and to obtain their elution curves, the chromatographic column containing Dowex 50 W-X 8 resin was employed. For efficient separation of lanthanides from interference elements the hydrochloric acid with concentration of two and six molar was used respectively. Recovery of lanthanides from the leach liquor solution was achieved more than 85%

  9. 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%

  10. Batch adsorptive removal of Fe(III, Cu(II and Zn(II ions in aqueous and aqueous organic–HCl media by Dowex HYRW2-Na Polisher resin as adsorbents

    Directory of Open Access Journals (Sweden)

    Abdul-Aleem Soliman Aboul-Magd

    2016-09-01

    Full Text Available Of the metal ions in tap, Nile, waste and sea water samples and some ores were carried out. Removal of heavy metal ions such as Fe(III, Cd(II, Zn(II, Cu(II, Mn(II, Mg(II, and Pb(II from water and wastewater is obligatory in order to avoid water pollution. Batch shaking adsorption experiments to evaluate the performance of nitric and hydrochloric acid solutions in the removal of metal ions by cation exchange resin at the same conditions for both, such as the effect of initial metal ion concentration, different proportions of some organic solvents, H+-ion concentrations and reaction temperature on the partition coefficients. The metal adsorption for the cation exchanger was found to be significant in different media for both nitric and hydrochloric acids, i.e., the adsorption up take of metal ions presented in this work is very significant depending on the characteristics of ions and on the external concentrations of solute. The presence of low ionic strength or low concentration of acids does have a significant adsorption of metal ions on ion-exchange resin. The results show that the ion exchanger could be employed for the preconcentration, separation and the determination.

  11. Basic exchangeable cations in Finnish mineral soils

    Directory of Open Access Journals (Sweden)

    Armi Kaila

    1972-09-01

    Full Text Available The content of exchangeable Ca, Mg, K and Na replaced by neutral ammonium acetate was determined in 470 samples of mineral soils from various parts of Finland, except from Lapland. The amount of all these cations tended to increase with an increase in the clay content, but variation within each textural class was large, and the ranges usually overlapped those of the other classes. The higher acidity of virgin surface soils was connected with a lower average degree of saturation by Ca as compared with the corresponding textural classes of cultivated soils. No significant difference in the respective contents of other cations was detected. The samples of various textural groups from deeper layers were usually poorer in exchangeable Ca and K than the corresponding groups of plough layer. The mean content of exchangeable Mg was equal or even higher in the samples from deeper layers than in the samples from plough layer, except in the group of sand soils. The percentage of Mg of the effective CEC increased, as an average, from 9 in the sand and fine sand soils of plough layer to 30 in the heavy clay soils; in the heavy clay soils from deeper layers its mean value was 38 ± 4 %. In the samples of plough layer, the mean ratio of Ca to Mg in sand and fine sand soils was about 9, in silt and loam soils about 6, in the coarser clay soils about 4, and in heavy clay about 2.

  12. Enrofloxacin sorption on smectite clays: effects of pH, cations, and humic acid.

    Science.gov (United States)

    Yan, Wei; Hu, Shan; Jing, Chuanyong

    2012-04-15

    Enrofloxacin (ENR) occurs widely in natural waters because of its extensive use as a veterinary chemotherapeutic agent. To improve our understanding of the interaction of this emerging contaminant with soils and sediments, sorption of ENR on homoionic smectites and kaolinite was studied as a function of pH, ionic strength, exchangeable cations, and humic acid concentration. Batch experiments and in situ ATR-FTIR analysis suggested multiple sorption mechanisms. Cation exchange was a major contributor to the sorption of cationic ENR species on smectite. The decreased ENR sorption with increasing ionic strength indicated the formation of outer-sphere complexes. Exchangeable cations significantly influenced the sorption capacity, and the observed order was Csacid had a negligible contribution to the interlayer intercalation. The results of this study provide new insight into the molecular mechanisms of ENR sorption on clay minerals. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Biodiesel purification methodology produced in the RECOPE experimental plant, using ion exchange resins

    International Nuclear Information System (INIS)

    Calderon Hernandez, Teresita

    2016-01-01

    A methodology was proposed for the biodisel purification of crude palm oil produced in a plant located on the Refinadora Costarricense de Petroleo (RECOPE) campus in Alto de Ochomogo, using ion exchange resins. A comparison between two resins was carried out: the USF C-211H, which had been acquired together with the RECOPE experimental plant and the PD206 resin, which was in the process of being acquired at the time of starting the project. The biodisel was eluted by glass columns packed with each resin, to determine the saturation of the same. The percentage of free and bound glycerin and the presence of soaps were analyzed as response variables. With the results obtained, it was determined that the PD206 resin is more efficient in the removal of glycerin, soaps and methanol than the resin USF C-211H. However, neither of the two resins diminishes the acidity of the biodisel. A biodisel sample was eluted by the PD206 resin and the quality of the obtained product was analyzed. A flash point of 145 degrees was obtained. A total acid number of 0.82 mg KOH / G was shown, no presence of water or sediment was observed. The percentage value of carbon residue was 0.01% m / m, the cloud point was 12 degrees, the density at 15 degrees was 0.8713 g / cm 3 , the viscosity at 40 degrees was 2.75 mm 2 /s; the stability to oxidation was 14.5 h, the percentage of free glycerin was 0.01% m / m and the percentage of total glycerin was 0.06% m / m, finally a percentage of Fatty Acids Methyl Esters (FAME) of 98,6%. Of the analyzed parameters, all are within the limits established in the Reglamento Tecnico Centroamericano except the acidity value, which exceeds the maximum value of 0.05 mg KOH / g sample. An economic analysis was carried out to evaluate which resin provides the best option to complete the purification process of the biodisel produced. The PD206, despite being more expensive, purifies a larger volume of biodiesel, so for a better negotiation in the purchase price, this

  14. SEPARATION OF BARIUM VALUES FROM URANYL NITRATE SOLUTIONS

    Science.gov (United States)

    Tompkins, E.R.

    1959-02-24

    The separation of radioactive barium values from a uranyl nitrate solution of neutron-irradiated uranium is described. The 10 to 20% uranyl nitrate solution is passed through a flrst column of a cation exchange resin under conditions favoring the adsorption of barium and certain other cations. The loaded resin is first washed with dilute sulfuric acid to remove a portion of the other cations, and then wash with a citric acid solution at pH of 5 to 7 to recover the barium along with a lesser amount of the other cations. The PH of the resulting eluate is adjusted to about 2.3 to 3.5 and diluted prior to passing through a smaller second column of exchange resin. The loaded resin is first washed with a citric acid solution at a pH of 3 to elute undesired cations and then with citric acid solution at a pH of 6 to eluts the barium, which is substantially free of undesired cations.

  15. Use of the cation exchange equilibrium method for the determination of stability constants of Co(II) with soil humic and fulvic acids

    International Nuclear Information System (INIS)

    Du, J.Z.; Zhou, C.Y.; Dong, W.M.; Tao, Z.Y.

    1999-01-01

    The stability constants for tracer concentrations of Co(II) complexes with both the red earth humic and fulvic acids were determined at pH 5.9 and ionic strength 0.010 mol/l by using the ARDAKANI-STEVENSON cation exchange equilibrium method and the radiotracer 60 Co. It was found that the 1:1 complexes of Co(II) with the red earth humic and fulvic acids were formed and that the average values of logβ (stability constant) of humic and fulvic acid complexes were 5.76±0.19 and 4.42±0.03, respectively. (author)

  16. 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

  17. Biocompatibility Research of a Novel pH Sensitive Ion Exchange Resin Microsphere.

    Science.gov (United States)

    Liu, Hongfei; Shi, Shuangshuang; Pan, Weisan; Sun, Changshan; Zou, Xiaomian; Fu, Min; Feng, Yingshu; Ding, Hui

    2014-01-01

    The main objective of this study was to investigate biocompatibility and provide in-vivo pharmacological and toxicological evidence for further investigation of the possibility of pH sensitive ion exchange resin microsphere for clinical utilizations. Acute toxicity study and general pharmacological studies were conducted on the pH sensitive ion exchange resin microsphere we prepared. The general pharmacological studies consist of the effects of the pH sensitive ion exchange resin microsphere on the nervous system of mice, the functional coordination of mice, the hypnosis of mice treated with nembutal at subliminal dose, the autonomic activities of tested mice, and the heart rate, blood pressure, ECG and breathing of the anesthetic cats. The LD50 of pH sensitive ion exchange resin microsphere after oral administration was more than 18.84 g·Kg(-1). Mice were orally administered with 16 mg·Kg(-1), 32 mg·Kg(-1) and 64 mg·Kg(-1) of pH sensitive ion exchange resin microsphere and there was no significant influence on mice nervous system, general behavior, function coordination, hypnotic effect treated with nembutal at subliminal dose and frequency of autonomic activities. Within the 90 min after 5 mg·Kg(-1), 10 mg·Kg(-1), 20 mg·Kg(-1) pH sensitive ion exchange resin microsphere was injected to cat duodenum, the heart rate, blood pressure, breathing and ECG of the cats didn't make significant changes in each experimental group compared with the control group. The desirable pharmacological and toxicological behaviors of the pH sensitive ion exchange resin microsphere exhibited that it has safe biocompatibility and is possible for clinical use.

  18. 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)

  19. 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)

  20. Synthesis, dehydration studies, and cation-exchange behavior of a new phase of niobium(V) phosphate

    International Nuclear Information System (INIS)

    Qureshi, M.; Ahmad, A.; Shakeel, N.A.; Gupta, A.P.

    1986-01-01

    Twenty-three samples of niobium(V) phosphate have been synthesized under different conditions using niobium sulfate and phosphoric acid solutions. The amorphous sample having the ion-exchange capacity of 1.06 mEq g -1 and niobium to phosphorus mole ratio of 0.670 was studied in detail for its cation-exchange behavior. Molar distribution coefficients for 25 cations have been studied on this gel at pH 1,2,3, and 5.5. Four quantitative separations of Mg 2+ -Ca 2+ , Mg 2+ -Ba 2+ , Zn 2+ -Cd 2+ , and Bi 3+ -Zn 2+ have successfully been achieved on it. The properties of this sample have been compared with those of niobium arsenate, niobium antimonate, and niobium molybdate. A tentative structural formula is proposed for this sample of niobium phosphate on the basis of chemical composition, cation-exchange capacity, pH-titration, IR spectra, T.G.A., water absorption, and heat treatment data. (author)

  1. Bench scale studies on separation of rare earths by ion exchange

    International Nuclear Information System (INIS)

    Aroonrung-Areeya, A.

    1976-01-01

    The method of ion exchange was applied to the separation of mixtures of rare earth oxides into the pure components. The method consists of eluting a band of mixed rare earths adsorbed on a cation-exchange resin through a second cation-exchange bed in the copper II state. The eluent consists of an ammonia buffered solution of ethylenediamine tetraacetic acid. The mixed rare earth oxide used as testing material was obtained from the digestion of Thai monazite. The amounts varied from 1, 5 to 50 grams. The purity of the rare earth fractions were analyzed either by neutron activation of X-ray fluorescence. The Cu.EDTA was recovered by the addition of lime. It was found that gram quantities of pure rare earths could be obtained by this method

  2. The elution of erbium from a cation exchanger bed by means of the N-hydroxyethyl-ethylene-diamine triacetic acid

    International Nuclear Information System (INIS)

    Amer Amezaga, S.

    1963-01-01

    A physicochemical study of the phenomena resulting when erbium is eluted from a cation-exchanger bed at a steady by means of the N-hydroxyethyl-ethylene-diamine-triacetic acid (HEDTA) is made. Two different retaining beds are used, a hydrogen bed, in which no ammonium passes through, and a zinc bed, which leaks ammonium ion. Good agreement between experimental and calculated values by using the equations deduced for the concentrations of the main species has been achieved, with errors around 1-2% in most of the experiments. (Author) 69 refs

  3. 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

  4. Converting Hg-1212 to Tl-2212 via Tl-Hg cation exchange in combination with Tl cation intercalation

    International Nuclear Information System (INIS)

    Zhao Hua; Wu, Judy Z

    2007-01-01

    In a cation exchange process developed recently for epitaxy of HgBa 2 CaCu 2 O 6 (Hg-1212) thin films, TlBa 2 CaCu 2 O 7 (Tl-1212) or Tl 2 Ba 2 CaCu 2 O 9 (Tl-2212) precursor films were employed as the precursor matrices and Hg-1212 was obtained by replacing Tl cations on the precursor lattice with Hg cations. The reversibility of the cation exchange dictates directly the underlying mechanism. Following our recent success in demonstrating a complete reversibility within '1212' structure, we show the conversion from Hg-1212 to Tl-2212 can be achieved via two steps: conversion from Hg-1212 to Tl-1212 followed by Tl intercalation to form double Tl-O plans in each unit cell. The demonstrated reversibility of the cation exchange process has confirmed the process is a thermal perturbation of weakly bonded cations on the lattice and the direction of the process is determined by the population ratio between the replacing cations and that to be replaced

  5. Effect of the intercalated cation-exchanged on the properties of nanocomposites prepared by 2-aminobenzene sulfonic acid with aniline and montmorillonite

    Energy Technology Data Exchange (ETDEWEB)

    Toumi, I. [Laboratoire de Chimie Organique, Macromoleculaire et des Materiaux, Universite de Mascara, Bp 763 Mascara 29000 (Algeria); Benyoucef, A., E-mail: ghani29000@yahoo.fr [Laboratoire de Chimie Organique, Macromoleculaire et des Materiaux, Universite de Mascara, Bp 763 Mascara 29000 (Algeria); Yahiaoui, A. [Laboratoire de Chimie Organique, Macromoleculaire et des Materiaux, Universite de Mascara, Bp 763 Mascara 29000 (Algeria); Quijada, C. [Departamento de Ingenieria Textil y Papelera, Universidad Politecnica de Valencia, Pza Ferrandiz i Carbonel, E-03801 Alcoy, Alicante (Spain); Morallon, E. [Departamento de Quimica Fisica e Instituto Universitario de Materiales, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain)

    2013-02-25

    Polymer/montmorillonite nanocomposites were prepared. Intercalation of 2-aminobenzene sulfonic acid with aniline monomers into montmorillonite modified by cation was followed by subsequent oxidative polymerization of monomers in the interlayer spacing. The clay was prepared by cation exchange process between sodium cation in (M-Na) and copper cation (M-Cu). XRD analyses show the manifestation of a basal spacing (d-spacing) for M-Cu changes depending on the inorganic cation and the polymer intercalated in the M-Cu structure. TGA analyses reveal that polymer/M-Cu composites is less stable than M-Cu. The conductivity of the composites is found to be 10{sup 3} times higher than that for M-Cu. The microscopic examinations including TEM picture of the nanocomposite demonstrated an entirely different and more compatible morphology. Remarkable differences in the properties of the polymers have also been observed by UV-Vis and FTIR, suggesting that the polymer produced with presence of aniline has a higher degree of branching. The electrochemical behavior of the polymers extracted from the nanocomposites has been studied by cyclic voltammetry which indicates the electroactive effect of nanocomposite gradually increased with aniline in the polymer chain.

  6. SHALLOW SHELL RESIN VERSUS TRADITIONAL RESIN: A CASE STUDY FOR Cu(II REMOVAL

    Directory of Open Access Journals (Sweden)

    Özgür Arar

    2016-10-01

    Full Text Available A comparative study on Cu2+ removal by shallow shell resin (Purolite SST 60 and traditional strongly acidic cation exchange resin (Purolite PFC 100 was performed. Batch experiments were carried out as a function of  resin  dosage and  solution pH and contact time. Ion exchange reaction showed a pH depended feature.  Maximum removal of Cu2+ achieved  pH  from 2 to 5. Sorption isothermal data is well interpreted by the Langmuir equation. Additionally, kinetic experiments showed that the pseudo first-order model was suitable for such resins. The regeneration performance of shallow shell technology (SST resin is better than PFC 100.  A solution of 2M H2SO4 performed well in regenerationof SST 60 resin. On the other han maximum regeneration reached 80% for PFC 100 resin.Özet: Bu çalışmada, klasik iyon değiştirici reçine (Purolite PFC 100 ve  sığ kabuk  reçine (Purolite SST 60  ile Cu2+ giderilmesi incelenmiştir. Yapılan kesikli çalışmalarla Cu2+ giderilmesine, reçine miktarı, çözelti pH`ı ve temas süresinin etkisi incelenmiştir. Çözelti pH`ının 2 ile 5 arasında olduğu durumda Cu2+ iyonları tamamen giderilmiştir. Denge çalışmalarında elde edilen sonuçlar Langmuir izoterm modeline daha uygun olmuştur. Kinetik çalışmalarda elde edilen sonuçlar yalancı birinci mertebe kinetik modeline uygunluk göstermişir. SST 60 reçinesinin rejenerasyon verimi PFC 100 reçinesinden daha yüksektir. 2M H2SO4 ile SST 60 reçinesi tamamen rejenere edilmiştir.

  7. Technical Task and Quality Assurance Plan in Support of BNFL Part B: Studies of Ion Exchange Resin Integrity under Flowsheet Extremes: Part II

    International Nuclear Information System (INIS)

    Nash, C.A.

    2000-01-01

    This task will address four items related to ion exchange stability: (1) process upset evaluation of resin in contact with 1 molar sodium permanganate at 25 and 40 degrees C, (2) accelerated aging with nitric acid solution used during normal regeneration operations, (3) prolonged contacting of SuperLig 644 resin with 5 molar nitric acid at room temperature, and (4) prolonged contacting of SuperLig 644 resin with deionized water at 60 plus/minus 5 degrees C

  8. 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

  9. 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.

  10. Carbonylation of 1-hexene in the presence of palladium-anion-exchange resin catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Lapidus, A.L.; Pirozhkov, S.D.; Buiya, M.A.; Lunin, A.F.; Karapetyan, L.P.; Saldadze, K.M.

    1986-06-20

    Activated charcoal, silica gel, and zeolites containing palladium are active in the carbonylation of lower olefins by carbon monoxide. In the present work, they studied the carbonylation of 1-hexene in the presence of a series of palladium catalysts containing An-221, An-251, and AN-511 anion-exchange catalysts produced in the USSR as the supports. A catalyst obtained by the deposition of palladium(II) on weakly basic anion-exchange resins displays high efficiency in the carbonylation of 1-hexene with the formation of a nixture of enanthoic and 2-methylcaproic acids.

  11. Effect of cation exchange of major cation chemistry in the large scale redox experiment at Aespoe. Revision 1

    International Nuclear Information System (INIS)

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

    1996-06-01

    Geochemical modeling was used to test the hypothesis that cation exchange with fracture-lining clays during fluid mixing in the Aespoe Hard Rock Laboratory can significantly affect major element chemistry. Conservative mixing models do not adequately account for changes in Na, Ca and Mg concentrations during mixing. Mixing between relatively dilute shallow waters and more concentrated waters at depth along fracture zones was modeled using the EQ3/6 geochemical modeling package. A cation exchange model was added to the code to describe simultaneously aqueous speciation, mineral precipitation/dissolution, and equilibration between a fluid and a cation exchanger. Fluid chemistries predicted to result from mixing were compared with those monitored from boreholes intersecting the fracture zone. Modeling results suggest that less than 0.1 equivalent of a smectite exchanger per liter of groundwater is necessary to account for discrepancies between predictions from a conservative mixing model and measured Na and Ca concentrations. This quantity of exchanger equates to an effective fracture coating thickness of 20 microm or less given a fracture aperture width of 1,000 microm or less. Trends in cation ratios in the fluid cannot be used to predict trends in cation ratios on the exchanger because of the influence of ionic strength on heterovalent exchange equilibrium. It is expected that Na for Ca exchange will dominate when shallow waters such as HBHO2 are mixed with deeper waters. In contrast, Na for Mg exchange will dominate mixing between deeper waters

  12. Distribution of Components in Ion Exchange Materials Taken from the K East Basin and Leaching of Ion Exchange Materials by Nitric/Hydrofluoric Acid and Nitric/Oxalic Acid

    International Nuclear Information System (INIS)

    Delegard, C.H.; Rinehart, D.E.; Hoopes, F.V.

    1998-01-01

    Laboratory tests were performed to examine the efficacy of mixed nitric/hydrofluoric acid followed by mixed nitric/oxalic acid leach treatments to decontaminate ion exchange materials that have been found in a number of samples retrieved from K East (KE)Basin sludge. The ion exchange materials contain organic ion exchange resins and zeolite inorganic ion exchange material. Based on process records, the ion exchange resins found in the K Basins is a mixed-bed, strong acid/strong base material marketed as Purolite NRW-037. The zeolite material is Zeolon-900, a granular material composed of the mineral mordenite. Radionuclides sorbed or associated with the ion exchange material 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). Elutriation and washing steps are designed to remove the organic resins from the K Basin sludge. To help understand the effects of the anticipated separation steps, tests were performed with well-rinsed ion exchange (IX) material from KE Basin floor sludge (sample H-08 BEAD G) and with well-rinsed IX having small quantities of added KE canister composite sludge (sample KECOMP). Tests also were performed to determine the relative quantities of organic and inorganic IX materials present in the H-08 K Basin sludge material. Based on chemical analyses of the separated fractions, the rinsed and dry IX material H-08 BEAD G was found to contain 36 weight percent inorganic material (primarily zeolite). The as-received (unrinsed) and dried H-08 material was estimated to contain 45 weight percent inorganic material

  13. Radiation-induced decomposition of anion exchange resins

    International Nuclear Information System (INIS)

    Baidak, Aliaksandr; LaVerne, Jay A.

    2010-01-01

    Radiation-induced degradation of the strongly basic anion exchange resin Amberlite TM IRA400 in NO 3 - , Cl - and OH - forms has been studied. The research focused on the formation of molecular hydrogen in the gamma-radiolysis of water slurries of these quaternary ammonium resins with varying water content. Extended studies with various electron scavengers (NO 3 - , N 2 O and O 2 ) prove an important role of e solv - in the formation of H 2 from these resins. An excess production of H 2 in these systems at about 85% water weight fraction was found to be due to trimethylamine, dimethylamine and other compounds that leach from the resin to the aqueous phase. Irradiations with 5 MeV 4 He ions were performed to simulate the effects of α-particles.

  14. Chromatographic separation process with pellicular ion exchange resins that can be used for ion or isotope separation and resins used in this process

    International Nuclear Information System (INIS)

    Carles, M.; Neige, R.; Niemann, C.; Michel, A.; Bert, M.; Bodrero, S.; Guyot, A.

    1989-01-01

    For separation of uranium, boron or nitrogen isotopes, an isotopic exchange is carried out betwen an isotope fixed on an ion exchange resin and another isotope of the same element in the liquid phase contacting the resin. Pellicular resins are used comprising composite particulates with an inert polymeric core and a surface layer with ion exchange groups [fr

  15. 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

  16. Test procedure for anion exchange testing with Argonne 10-L solutions

    International Nuclear Information System (INIS)

    Compton, J.A.

    1995-01-01

    Four anion exchange resins will be tested to confirm that they will sorb and release plutonium from/to the appropriate solutions in the presence of other cations. Certain cations need to be removed from the test solutions to minimize adverse behavior in other processing equipment. The ion exchange resins will be tested using old laboratory solutions from Argonne National Laboratory; results will be compared to results from other similar processes for application to all plutonium solutions stored in the Plutonium Finishing Plant

  17. Improved management of SG BD demineralizer for reduced generation of low-level radioactive spent resin in Korean nuclear power plants

    International Nuclear Information System (INIS)

    Rhee, I.; Cho, D.; Yeon, J.

    2003-01-01

    Most nuclear power plants in Korea have adopted Ethanolamine(ETA) as a secondary pH control agent to increase the pH at the liquid phase, which may reduce the corrosion in steam generator tubes and moisture separator/reheat system. Along with its beneficial effect of SG protection from corrosion and degradation, the replacement of ammonia with ETA causes the increased generation of spent resin and the reduced run time of demineralizer in steam generator blowdown(SG BD) system. The composition ratio of cation- to anion- exchange resin in SG BD mixed bed should be increased in the ETA chemistry environment to meet the ratio of cation to anion in the aqueous solution, which results in the simultaneous exhaustion of cation and anion exchange resins. The utilization rate of mixed bed is greatest at the cation-to-anion ratio of 95:1 on the theoretical equivalent basis in the solution, but practically highest at that of 22:1 due to the possible inhomogeneous distribution of cation and anion exchange resins in SG BD bed. The run time of the bed could be extended by 30% such that, at that much, the purchase cost of new resin is saved and the production rate of spent resin is reduced. The guideline on the replacement of resin in SG BD bed is not necessary to secure the removal of radioactive particles without the leakage of the primary coolant into the secondary side since all the radioactive ions can be eliminated by SG BD bed with the sufficient time. They are retained during more than one month after their ingress into the SG BD bed without leakage. With the reduced replacement, thus, the SG BD spent resin that comprises 65% of low-level radioactive solid waste can be much cut down

  18. Fabrication of Cationic Exchange Polystyrene Nanofibers for Drug ...

    African Journals Online (AJOL)

    Purpose: To prepare polystyrene nanofiber ion exchangers (PSNIE) with surface cation exchange functionality using a new method based on electrospinning and also to optimize crosslinking and sulfonation reactions to obtain PSNIE with maximum ion exchange capacity (IEC). Method: The nanofibers were prepared from ...

  19. Immobilisation Of Spent Ion Exchange Resins Using Portland Cement Blending With Organic Material

    International Nuclear Information System (INIS)

    Zalina Laili; Mohd Abdul Wahab; Nur Azna Mahmud

    2014-01-01

    Immobilisation of spent ion exchange resins (spent resins) using Portland cement blending with organic material for example bio char was investigated. The performance of cement-bio char matrix for immobilisation of spent ion exchange resins was evaluated based on their compression strength and leachability under different experimental conditions. The results showed that the amount of bio char and spent resins loading effect the compressive strength of the waste form. Several factors affecting the leaching behaviour of immobilised spent resins in cement-bio char matrix. (author)

  20. Carbon dioxide capture using resin-wafer electrodeionization

    Science.gov (United States)

    Lin, YuPo J.; Snyder, Seth W.; Trachtenberg, Michael S.; Cowan, Robert M.; Datta, Saurav

    2015-09-08

    The present invention provides a resin-wafer electrodeionization (RW-EDI) apparatus including cathode and anode electrodes separated by a plurality of porous solid ion exchange resin wafers, which when in use are filled with an aqueous fluid. The apparatus includes one or more wafers comprising a basic ion exchange medium, and preferably includes one or more wafers comprising an acidic ion exchange medium. The wafers are separated from one another by ion exchange membranes. The fluid within the acidic and/or basic ion exchange wafers preferably includes, or is in contact with, a carbonic anhydrase (CA) enzyme to facilitate conversion of bicarbonate ion to carbon dioxide within the acidic medium. A pH suitable for exchange of CO.sub.2 is electrochemically maintained within the basic and acidic ion exchange wafers by applying an electric potential across the cathode and anode.

  1. Preparation of nuclear grade strongly basic anion exchange resin in hydroxide from

    International Nuclear Information System (INIS)

    Ke Weiqing

    1989-01-01

    The two-step transformation method was used to prepare 90 kg nuclear grade strongly basic anion exchange resins by using the industrial grade baking soda and caustic soda manufacutred by mercury-cathode electrolysis. The chloride and biscarbonate fraction on resin is 0.8% and 1.25% respectively, when the baking soda and caustic soda consumption is 8.6 and 13.7 times the total exchange capacity of the strongly basic resin

  2. Concentration and purification of plutonium solutions by means of ion-exchange columns

    Energy Technology Data Exchange (ETDEWEB)

    Durham, R W; Aikin, A M

    1953-02-15

    Equilibrium experiments using Dowex 50 ion-exchange resin and nitric acid solutions of Pu{sup 3+}, UO{sub 2}{sup 2+}, Fe{sup 2+} cations have yielded values for the absorption affinities for these ions. Trivalent plutonium was found to be far more strongly absorbed than UO{sub 2}{sup 2+} and Fe{sup 2+}. Column studies have shown that uranium can be completely separated from plutonium even when the initial concentration of uranium is very much greater than that of the plutonium. A plutonium concentration increase of about fifty-fold can be obtained from solutions about 10{sup -3} M in plutonium and 1.0M in nitric acid. The equation K{sub Pu}{sup 3+} = X{sub R} (1-X{sub S}){sup 3} C{sub S}{sup 2}/X{sub S} (1-X{sub R}){sup 3} C{sub R}{sup 2} for estimating the maximum amount of plutonium taken up by a column of resin of unit volume from a solution of total equivalent concentration, C{sub S} , has been shown to hold for values of C{sub S} up to 3 equivalents per litre. X{sub R}, the equivalent fraction of plutonium on the resin, is the number of equivalents of plutonium absorbed by the resin divided by the total capacity of the column. X{sub S}, the equivalent fraction of plutonium in solution, is the equivalent concentration of plutonium divided by the total equivalent concentration of cations in solution. C{sub R} is the total capacity of the resin in milli-equivalents per gram of dry resin. Recommendations have been made for the application and operation of ion-exchange columns in the Plutonium-Extraction Plant. (author)

  3. Management of spent ion-exchange resins from nuclear power plants

    International Nuclear Information System (INIS)

    1981-01-01

    Information presented at the IAEA organized Technical Committee Meeting in December 1976 is given on the management of spent ion-exchange resins with respect to their treatment and conditioning. Currently available processes, methods and technologies such as volume reduction techniques, immobilization techniques, etc. for the treatment and conditioning are described on the basis of operating experiences. Economic aspects associated with the use, treatment, packaging and disposal of ion-exchange resins are dealt with the purpose to serve as an example of an appropriate economic evaluation. The current and prospective status of the resin disposal in USA, France, Federal Republic of Germany, United Kingdom and India is briefly discussed

  4. Chromatographic cation exchange separation of decigram quantities of californium and other transplutonium elements

    Energy Technology Data Exchange (ETDEWEB)

    Benker, D.E.; Chattin, F.R.; Collins, E.D.; Knauer, J.B.; Orr, P.B.; Ross, R.G.; Wiggins, J.T.

    1980-01-01

    Decigram quantities of highly radioactive transplutonium elements are routinely partitioned at TRU by chromatographic elution from cation resin using AHIB eluent. By using two high-pressure ion exchange columns, a small one for the initial loading of the feed and a large one for the elution, batch runs containing up to 200 mg of /sup 252/Cf can be made in about 5 hours (2 hours to load the feed and 3 hours for the elution). The number of effluent product fractions and the amount of actinides that must be collected in intermediate fractions are minimized by monitoring response from a flow-through alpha-detector. This process has been reliable and relatively easy to operate, and will continue to be used for partitioning transplutonium elements at TRU.

  5. Separation of 1,3-Propanediol from Aqueous Solutions by Ion Exchange Chromatography

    Directory of Open Access Journals (Sweden)

    Rukowicz Beata

    2014-06-01

    Full Text Available 1,3-propanediol is a promising monomer with many applications and can be produced by bioconversion of renewable resources. The separation of this product from fermentation broth is a difficult task. In this work, the application of cation exchange resin for the separation of 1,3-propanediol from model aqueous solution was examined. The best effect of separation of 1,3-propanediol from glycerol using sorption method was obtained for H+ resin form, although the observed partition coefficient of 1,3-propanediol was low. On the basis of the results of the sorption of 1,3-propanediol, the ionic forms of the resin were selected and used in the next experiments (H+, Ca2+, Ag+, Na+, Pb2+, Zn2+. The best results in ion exchange chromatography were obtained for cation exchange resin in H+ and Ca2+ form. The use of smaller particle size of resin and a longer length of the column allows to obtain better separation of mixtures.

  6. Organic resin anion exchangers for the treatment of radioactive wastes

    International Nuclear Information System (INIS)

    Dyer, A.; McGinnes, D.F.

    1988-07-01

    Organic anion exchange resins are evaluated for 99-TcO 4 - (pertechnate) removed from aqueous nuclear waste streams. Chemical, thermal and radiation stabilities were studied. Selected resins were examined in detail for their selectivities in the presence of I - , NO 3 - , SO 4 = , CO 3 = , Cl - and OH - . Ion exchange equilibria and kinetic mechanisms were determined. Preliminary investigations of cement encapsulation in polymer modified form were made and some leach studies carried out. (author)

  7. Selective cation-exchange separation of cesium(I) on chromium ferricyanide gel

    International Nuclear Information System (INIS)

    Jain, A.K.; Agrawal, S.; Singh, R.P.

    1980-01-01

    The removal of 137 Cs from liquid streams of nuclear power plants and from processed radioactive waste of nuclear fission has received increasing attention from ion-exchange chemists. A desirable exchanger (adsorbent) for 137 Cs removal is one which can adsorb it significantly and selectively in the presence of appreciable amounts (approx. 2molL -1 ) of Na + , NH 4 + , and H + . This paper deals with the exchange properties of the inorganic exchanger, chromium ferricyanide gel (CFiC). The stability of the gel in both acid and salt solutions and its high specificity for cesium are responsible for its good scavanger properties in removing long lived 137 Cs from radioactive waste. The chromium ferricyanide exchanger is highly selective for monovalent cations, the order being Ag + >Tl + >Cs + >Rb + >K + >Na + . It does not adsorb any bivalent, trivalent, and tetravalent ions even when present in trace amounts. (2 figures, 3 tables)

  8. Anion-exchange Studies of Radioactive Trace Elements in Sulphuric Acid Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Samsahl, K

    1963-01-15

    As part of a chemical group separation procedure used as a pretreatment in gamma spectrometric analysis, a study has been made of the adsorption from sulphuric acid solutions on strongly basic anion exchange resins, prepared in the hydroxide and the sulphate forms, of trace activities of Na, P, K, Ca, Sc, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Rb, Sr, Zr, Nb, Mo, Tc, Ag, Cd, In, Cs, Ba, La, Ce, Hf, Ta, W, Ir, Pa and Np. Besides adsorbing some of the trace elements in the solution, the anion exchange resin in the hydroxide form will neutralize the bulk of the sulphuric acid. This makes possible the subsequent sequential separation of chloride complexes on short anion-exchange columns by a stepwise increasing of the HCl concentration of the solution. On the basis of the results obtained in the present and earlier experiments, a new improved chemical group-separation procedure for mixtures of radioactive trace elements is outlined.

  9. Fermentation and recovery of L-glutamic acid from cassava starch hydrolysate by ion-exchange resin column

    Directory of Open Access Journals (Sweden)

    Nampoothiri K. Madhavan

    1999-01-01

    Full Text Available Investigations were carried out with the aim of producing L-glutamic acid from Brevibacterium sp. by utilizing a locally available starchy substrate, cassava (Manihot esculenta Crantz. Initial studies were carried out in shake flasks, which showed that even though the yield was high with 85-90 DE (Dextrose Equivalent value, the maximum conversion yield (~34% was obtained by using only partially digested starch hydrolysate, i.e. 45-50 DE. Fermentations were carried out in batch mode in a 5 L fermenter, using suitably diluted cassava starch hydrolysate, using a 85-90 DE value hydrolysate. Media supplemented with nutrients resulted in an accumulation of 21 g/L glutamic acid with a fairly high (66.3% conversation yield of glucose to glutamic acid (based on glucose consumed and on 81.74% theoretical conversion rate. The bioreactor conditions most conducive for maximum production were pH 7.5, temperature 30°C and an agitation of 180 rpm. When fermentation was conducted in fed-batch mode by keeping the residual reducing sugar concentration at 5% w/v, 25.0 g/L of glutamate was obtained after 40 h fermentation (16% more the batch mode. Chromatographic separation by ion-exchange resin was used for the recovery and purification of glutamic acid. It was further crystallized and separated by making use of its low solubility at the isoelectric point (pH 3.2.

  10. On the mechanism of boron transfer through the cation-exchange membrane MK-40

    International Nuclear Information System (INIS)

    Pilipenko, A.T.; Varvaruk, L.A.; Grebenyuk, V.D.; Trachevskij, V.V.

    1985-01-01

    Proceses of boron electromigration in solutions with different pH values are investigated. It is shown, that boron transfer through ion-exchange membranes is determined by pH of solution. Phenomenon of boron transfer (existing in the solution in the form of boric acid) through cation-exchange membrane MK-40 has been detected and described for the first time. The process of boron (3) complexing with sulfate groups of the membrane by means of competing reversible substitution of hydroxoligands is the basis of the phenomenon

  11. The effect of various cations and pH on the adsorption of U(VI) on Amberlite IR-118H resin

    International Nuclear Information System (INIS)

    Kilislioglu, Ayben

    2003-01-01

    The effects of various metal cations and pH on the adsorption of uranium(VI) on strongly acidic cation exchanger Amberlite IR-118H (AIR-118H) were studied. The metal cations suppress U(VI) adsorption differently depending on their ionic radii. Adsorption of U(VI) on AIR-118H peaks at pH 3.4, which was attributed to the occurrence of different forms of U(VI) at different pH values. The adsorption data were then processed using the Frumkin-Fowler-Guggenheim equation, and the standard free energy of adsorption was calculated

  12. Tests of the use of cation exchange organic resins for the decontamination of radioactive aqueous effluents; Essais d'emploi des resines organiques echangeuses de cations pour la decontamination des effluents aqueux radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Bourdrez, Jean; Girault, Jacques; Wormser, Gerald

    1962-12-14

    The authors report tests performed in laboratory and results obtained during an investigation of the use of synthetic ion exchangers for the decontamination of radioactive effluents of moderate activity level and with a non neglectable salt loading. Resins are used under sodium form and regenerated after each fixing operation. Once decontaminated and free of its disturbing ions, the regenerating agent (NaCl) is used for several operations. The authors present the used resins, the treated effluents, describe the tests, and discuss the obtained results [French] Dans ce rapport nous faisons le point des essais et resultats obtenus au laboratoire au cours d'une etude concernant l'utilisation des echangeurs d'ions synthetiques pour la decontamination des effluents radioactifs de niveau d'activite moyenne et de charge en sels non negligeable. Les resines sont employees sous forme sodique et regenerees apres chaque operation de fixation. Le regenerant decontamine et debarrasse de ses ions genants est utilise pour plusieurs operations d'elution. Les seuls residus a stocker proviennent d'une part eventuellement d'un pretraitement de l'effluent, d'autre part, dans tous les cas des precipites consecutifs a la purification de l'eluant dont le traitement chimique est plus aise et donne lieu a des boues beaucoup moins volumineuses qu'une coprecipitation effectuee sur la totalite de l'effluent. (auteurs)

  13. Determination of degradation conditions of exchange resins containing technetium; Determinacion de condiciones de degradacion de resinas de intercambio conteniendo tecnecio

    Energy Technology Data Exchange (ETDEWEB)

    Rivera S, A.; Monroy G, F.; Quintero P, E., E-mail: aa_1190@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    The quantification of Tc-99 in spent exchange resins, coming from nuclear power plants, is indispensable to define their administration. The Tc-99 is a pure beta emitter of 210000 years of half-life, volatile and of a high mobility in water and soil. For this reason, the objective of this work is to establish a digestion method of ionic exchange resins containing technetium that retains more than 95% of this radioisotope. Mineralization tests were carried out of a resin Amberlite IRN-150 by means of an oxidation heat, in acid medium, varying the resin mass, the medium volume, the media type, the temperature and the digestion time. The digested samples were analyzed by gas chromatography to estimate the grade of their degradation. The {sup 99m}Tc was used as tracer to determine the technetium percentage recovered after mineralizing the resin. The digestion process depends on the temperature and the resin mass. At higher temperature better mineralization of samples and to greater resin mass to a constant temperature, less degradation of the resin. The spectra beta of the {sup 99m}Tc and {sup 99}Tc are presented. (Author)

  14. Boron isotope separation by ion exchange chromatography using weakly basic anion exchange resin

    International Nuclear Information System (INIS)

    Sakuma, Yoichi; Aida, Masao; Okamoto, Makoto; Kakihana, Hidetake

    1980-01-01

    Isotopic plateau displacement chromatography, a useful method for isotope separation is presented. The boric acid band formed in a column of weakly basic anion exchange resin Diaion WA21 can be eluted with pure water. In order to obtain good accumulation of the isotope effect, a series of experiments with different migration length were carried out. The boron-10 enriched part of the boric acid absorbed band was always preceded by the isotopic plateau part, in which the atomic fraction of boron-10 was maintained at its original value. The atomic fraction of boron-10 at the end of the chromatogram increased with migration length, and in the case of 256-m migration, boron-10 was enriched from its original atomic fraction of 19.84 to 91.00%, the separation factor S being constant irrespective of migration length: S = 1.0100 +- 0.0005. (author)

  15. 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)

  16. Sorption by cation exchange

    International Nuclear Information System (INIS)

    Bradbury, M.H.; Baeyens, B.

    1994-04-01

    A procedure for introducing exchange into geochemical/surface complexation codes is described. Beginning with selectivity coefficients, K c , defined in terms of equivalent fractional ion occupancies, a general expression for the molar based exchange code input parameters, K ex , is derived. In natural systems the uptake of nuclides onto complex sorbents often occurs by more than one mechanism. The incorporation of cation exchange and surface complexation into a geochemical code therefore enables sorption by both mechanisms to be calculated simultaneously. The code and model concepts are tested against sets of experimental data from widely different sorption studies. A proposal is made to set up a data base of selectivity coefficients. Such a data base would form part of a more general one consisting of sorption mechanism specific parameters to be used in conjunction with geochemical/sorption codes to model and predict sorption. (author) 6 figs., 6 tabs., 26 refs

  17. Removal of Ca(II) and Mg(II) from potassium chromate solution on Amberlite IRC 748 synthetic resin by ion exchange

    International Nuclear Information System (INIS)

    Yu Zhihui; Qi Tao; Qu Jingkui; Wang Lina; Chu Jinglong

    2009-01-01

    Experimental measurements have been made on the batch ion exchange of Ca(II) and Mg(II) from potassium chromate solution using cation exchanger of Amberlite IRC 748 as K + form. The ion exchange behavior of two alkaline-earth metals on the resin, depending on contact time, pH, temperature and resin dosage was studied. The adsorption isotherms were described by means of the Langmuir and Freundlich isotherms. For Ca(II) ion, the Langmuir model represented the adsorption process better than the Freundlich model. The maximum ion exchange capacity was found to be 47.21 mg g -1 for Ca(II) and 27.70 mg g -1 for Mg(II). The kinetic data were tested using Lagergren-first-order and pseudo-second-order kinetic models. Kinetic data correlated well with the pseudo-second-order kinetic model, indicating that the chemical adsorption was the rate-limiting step. Various thermodynamic parameters such as Gibbs free energy (ΔG o ), enthalpy (ΔH o ) and entropy (ΔS o ) were also calculated. These parameters showed that the ion exchange of Ca(II) and Mg(II) from potassium chromate solution was feasible, spontaneous and endothermic process in nature. The activation energy of ion-exchange (E a ) was determined as 12.34 kJ mol -1 for Ca(II) and 9.865 kJ mol -1 for Mg(II) according to the Arrhenius equation.

  18. Lawps ion exchange column gravity drain of spherical resorcinol formaldehyde resin

    Energy Technology Data Exchange (ETDEWEB)

    Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Herman, D. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Restivo, M. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-01-28

    Experiments at several different scales were performed to understand the removal of spherical resorcinol formaldehyde (sRF) ion exchange resin using a gravity drain system with a valve located above the resin screen in the ion exchange column (IXC). This is being considered as part of the design for the Low Activity Waste Pretreatment System (LAWPS) to be constructed at the DOE Hanford Site.

  19. Method for in situ determination cation exchange capacities of subsurface formations

    International Nuclear Information System (INIS)

    Fertl, W.H.; Welker, D.W.

    1980-01-01

    A method is disclosed for the in situ examination of each subsurface formation penetrated by a borehole to ascertain the cation exchange capacity of such formations within a geological region. Natural γ ray logging is used to develop signals functionally related to the total γ radiation and to the potassium-40, uranium and thorium energy-band radiations. A first borehole is traversed by a potential γ ray spectrometer to provide selected measurements of natural γ radiation. Core samples are taken from the logged formation and laboratory tests performed to determine the cation exchange capacity thereof. The cation exchange capacities thus are developed then correlated with selected parameters provided by the γ ray spectrometer to establish functional relationships. Cation exchange capacities of formations in subsequent boreholes within the region are then determined in situ by use of the natural γ ray spectrometer and these established relationships. (author)

  20. Method of heat decomposition for chemical decontaminating resin waste

    International Nuclear Information System (INIS)

    Kikuchi, Akira.

    1988-01-01

    Purpose: To make resin wastes into non-deleterious state, discharge them into a resin waste storage tank of existent radioactive waste processing facility and store and dispose them. Constitution: In the processing of chemical decontaminating resin wastes, iron exchange resins adsorbing chemical decontaminating agents comprising a solution of citric acid, oxalic acid, formic acid and EDTA alone or as a mixture of them are heated to dry, thermally decomposed and then separated from the ion exchange resins. That is, the main ingredients of the chemical decontaminating agents are heat-decomposed when heated and dried at about 250 deg C in air and converted into non-toxic gases such as CO, CO 2 , NO, NO 2 or H 2 O. Further, since combustion or carbonization of the basic materials for the resin is not caused at such a level of temperature, the resin wastes removed with organic acid and chelating agents are transferred to an existent resin waste storage tank and stored therein. In this way, facility cost and radiation exposure can remarkably be decreased. (Kamimura, M.)

  1. 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.

  2. Quantitative electrochromatography of uranium and platinum on papers impregnated with thorium and antimony based cation exchanger

    International Nuclear Information System (INIS)

    Misra, A.K.

    1992-01-01

    Electrochromatography of 32 metal ions have been studied on papers impregnated with thorium antimonate cation exchanger in aq. organic acids, aq. nitric acid as well as in EDTA buffers. On the basis of differential migration which depends on the ion exchange properties of thorium antimonate and nature of complexes formed with the electrolytes, some useful qualitative and quantitative separations of synthetic mixtures of metal ions have been achieved. The effect of some other physical parameter has also been discussed. Quantitative separation of platinum and uranium has been developed. (author). 13 refs., 2 figs., 5 tabs

  3. Modification of Aliphatic Petroleum Resin by Peracetic Acid

    OpenAIRE

    Bondaletov, Vladimir Grigoryevich; Bondaletova, Lyudmila Ivanovna; Hamlenko, A.; Bondaletov, Oleg Vladimirovich; Starovoit, M.

    2014-01-01

    This work demonstrates the possibility of obtaining modified aliphatic resin (PRC5) by means of petroleum resin oxidation by peracetic acid. We have experimentally determined oxidation conditions that lead to producing resin with maximum epoxy and acid numbers. Ratio of "oxidative system: PRC5" is 0.5:1, process duration is 2 hours. The modified resin structure is determined by IR and NMR spectroscopy.

  4. Chelation Ion Exchange Properties of 2, 4-Dihydroxyacetophenone-Biuret-Formaldehyde Terpolymer Resin

    Directory of Open Access Journals (Sweden)

    Sanjiokumar S. Rahangdale

    2009-01-01

    Full Text Available The terpolymer resin 2, 4-HABF has been synthesized by the condensation of 2, 4-dihydroxyacetophenone (2, 4-HA and biuret (B with formaldehyde (F in 1:1:2 molar ratios in presence of 2 M hydrochloric acid as catalyst. UV-Visible, IR and proton NMR spectral studies have been carried out to elucidate the structure of the resin. A terpolymer (2, 4-HABF proved to be a selective chelating ion exchange polymer for certain metals. Chelating ion-exchange properties of this polymer were studied for Fe3+, Cu2+, Ni2+, Co2+, Zn2+, Cd2+ and Pb2+ ions. A batch equilibrium method was employed in the study of the selectivity of metal ion uptake involving the measurement of the distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in media of various ionic strengths. The polymer showed highest selectivity for Fe3+, Cu2+ ions than for Ni2+, Co2+, Zn2+, Cd2+, and Pb2+ ions. Study of distribution ratio as a formation of pH indicates that the amount of metal ion taken by resin is increases with the increasing pH of the medium.

  5. Radiation stability of anion-exchange resins based on epichlorohydrin and vinylpyridines

    International Nuclear Information System (INIS)

    Zainutdinov, S.S.; Dzhalilov, A.T.; Askarov, M.A.

    1983-01-01

    The vigorous development of nuclear technology and atomic energy and the hydrometallurgy of the rare and radioactive metals has made it necessary to create and use ion-exchange materials possessing a high resistance to the action of ionizing radiations and the temperature. In view of this, the necessity has arisen for obtaining ion-exchange materials possessing adequate radiation stability. The results of an investigation of the radiation stability of anion-exchange resins based on the products of spontaneous polymerization in the interaction of epichlorohydrin with vinylpyridines show that they possess higher radiation resistance than the industrial anion-exchange resin AN-31 used at the present time

  6. Composition of atmospheric precipitation. I. Sampling technique. Use of ion exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Egner, H; Eriksson, E; Emanuelsson, A

    1947-01-01

    In order to investigate the composition of atmospheric precipitations in Sweden, a technique using ion exchange resins has been developed. The possibilities of nitrate reduction, and ammonia losses, when the precipitation is collected in zinc gauges is stressed. Glass funnels are used, and they are effectively protected from bird droppings. The ion exchange resins so far available are quite serviceable but show some deficiencies as to stability, and activity in alkaline solutions. New resins, which are not yet available, seem to offer definite advantages.

  7. 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.

  8. Production of citric acid using its extraction wastewater treated by anaerobic digestion and ion exchange in an integrated citric acid-methane fermentation process.

    Science.gov (United States)

    Xu, Jian; Chen, Yang-Qiu; Zhang, Hong-Jian; Tang, Lei; Wang, Ke; Zhang, Jian-Hua; Chen, Xu-Sheng; Mao, Zhong-Gui

    2014-08-01

    In order to solve the problem of extraction wastewater pollution in citric acid industry, an integrated citric acid-methane fermentation process is proposed in this study. Extraction wastewater was treated by mesophilic anaerobic digestion and then used to make mash for the next batch of citric acid fermentation. The recycling process was done for seven batches. Citric acid production (82.4 g/L on average) decreased by 34.1 % in the recycling batches (2nd-7th) compared with the first batch. And the residual reducing sugar exceeded 40 g/L on average in the recycling batches. Pigment substances, acetic acid, ammonium, and metal ions in anaerobic digestion effluent (ADE) were considered to be the inhibitors, and their effects on the fermentation were studied. Results indicated that ammonium, Na(+) and K(+) in the ADE significantly inhibited citric acid fermentation. Therefore, the ADE was treated by acidic cation exchange resin prior to reuse to make mash for citric acid fermentation. The recycling process was performed for ten batches, and citric acid productions in the recycling batches were 126.6 g/L on average, increasing by 1.7 % compared with the first batch. This process could eliminate extraction wastewater discharge and reduce water resource consumption.

  9. Gamma radiation effect on gas production in anion exchange resins

    Energy Technology Data Exchange (ETDEWEB)

    Traboulsi, A. [CEA Marcoule, DEN/DTCD/SPDE/LCFI, BP 17171, 30207 Bagnols-sur-Cèze Cedex (France); E.A. LISA – METICA, Aix Marseille Université, Pôle de l’Etoile, case 451, 13397 Marseille Cedex 20 (France); Labed, V., E-mail: veronique.labed@cea.fr [CEA Marcoule, DEN/DTCD/SPDE/LCFI, BP 17171, 30207 Bagnols-sur-Cèze Cedex (France); Dauvois, V. [CEA Saclay, DEN/DANS/DPC/SECR/LSRM, 91191 Gif sur Yvette Cedex (France); Dupuy, N.; Rebufa, C. [E.A. LISA – METICA, Aix Marseille Université, Pôle de l’Etoile, case 451, 13397 Marseille Cedex 20 (France)

    2013-10-01

    Radiation-induced decomposition of Amberlite IRA400 anion exchange resin in hydroxide form by gamma radiolysis has been studied at various doses in different atmospheres (anaerobic, anaerobic with liquid water, and aerobic). The effect of these parameters on the degradation of ion exchange resins is rarely investigated in the literature. We focused on the radiolysis gases produced by resin degradation. When the resin was irradiated under anaerobic conditions with liquid water, the liquid phase over the resin was also analyzed to identify any possible water-soluble products released by degradation of the resin. The main products released are trimethylamine (TMA), molecular hydrogen (H{sub 2g}) and carbon dioxide (CO{sub 2g}). TMA and H{sub 2g} are produced in all the irradiation atmospheres. However, TMA was in gaseous form under anaerobic and aerobic conditions and in aqueous form in presence of liquid water. In the latter conditions, TMA{sub aq} was associated with aqueous dimethylamine (DMA{sub aq}), monomethylamine (MMA{sub aq}) and ammonia (NH{sub 4}{sup +}{sub aq}). CO{sub 2g} is formed in the presence of oxygen due to oxidation of organic compounds present in the system, in particular the degradation products such as TMA{sub g}.

  10. Studies on the application of temperature-responsive ion exchange polymers with whey proteins.

    Science.gov (United States)

    Maharjan, Pankaj; Campi, Eva M; De Silva, Kirthi; Woonton, Brad W; Jackson, W Roy; Hearn, Milton T W

    2016-03-18

    Several new types of temperature-responsive ion exchange resins of different polymer composition have been prepared by grafting the products from the co-polymerisation of N-phenylacrylamide, N-iso-propylacrylamide and acrylic acid derivatives onto cross-linked agarose. Analysis of the binding isotherms for these different resins obtained under batch adsorption conditions indicated that the resin based on N-iso-propylacrylamide containing 5% (w/w) N-phenylacrylamide and 5% (w/w) acrylic acid resulted in the highest adsorption capacity, Bmax, for the whey protein, bovine lactoferrin, e.g. 14 mg bovine lactoferrin/mL resin at 4 °C and 62 mg bovine lactoferrin/mL resin at 40 °C, respectively. Under dynamic loading conditions at 40 °C, 94% of the loaded bovine lactoferrin on a normalised mg protein per mL resin basis was adsorbed by this new temperature-responsive ion-exchanger, and 76% was eluted by a single cycle temperature shift to 4 °C without varying the composition of the 10mM sodium dihydrogen phosphate buffer, pH 6.5, or the flow rate. The binding characteristics of these different ion exchange resins with bovine lactoferrin were also compared to results obtained using other resins based on N-isopropylacrylamide but contained N-tert-butylacrylamide rather than N-phenylacrylamide, where the corresponding dynamic capture and release properties for bovine lactoferrin required different temperature conditions of 20 °C and 50 °C, respectively for optimal desorption/adsorption. The cationic protein, bovine lactoperoxidase, was also adsorbed and desorbed with these temperature-responsive resins under similar conditions of changing temperature, whereas the anionic protein, bovine β-lactoglobulin, was not adsorbed under this regime of temperature conditions but instead eluted in the flow-through. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. T/sub 4/ radioimmunoassay with ion-exchange resin separation

    Energy Technology Data Exchange (ETDEWEB)

    Michael, J D; Modha, K [Hoechst Pharmaceuticals Research Ltd., Milton Keynes (UK)

    1977-05-28

    An explanation is provided for the reports of falsely low values of serum-thyroxine (T/sub 4/) measured by radioimmunoassay (RIA), particularly in sera containing raised concentrations of thyroxine-binding globulin (TBG) (Burr, W.A., Evans, S.E., Hogan, T.C., 1977, Lancet, April 2, 757). A re-examination of the assay technique used in commercial RIA kits ('RIA-gnost T/sub 3/' and 'RIA-gnost T/sub 4/', Behring Diagnostics) showed that blocking of binding proteins by 8-anilino-1-naphthalene sulphonic acid (ANS) was incomplete in sera with raised TBG levels. Spectroscopic determination of the blocker concentration during the time the solution was in contact with the ion exchange resin showed that 98% of the ANS was removed from solution by 10 min contact with the resin, yet 60 min was required to absorb the free T/sub 4/. There was therefore ample time for unblocked TBG to recombine with free T/sub 4/ which was then misclassified as antibody-bound T/sub 4/. The assay technique used in the kits was therefore modified. The less polar TBG blocking agent, ethylmercurithiosalicylate (merthiolate), replaced ANS and it was demonstrated that accurate T/sub 3/ and T/sub 4/ measurements in high TBG sera could be made by resin-separation RIA without resorting to prior denaturation or alcohol extraction.

  12. Radiotracer application for characterization of nuclear grade anion exchange resins Tulsion A-23 and Dowex SBR LC

    International Nuclear Information System (INIS)

    Singare, P.U.

    2015-01-01

    Radio isotopic tracer technique as one of the versatile nondestructive technique is employed to evaluate the performance of nuclear grade anion exchange resins Tulsion A-23 and Dowex SBR LC. The evaluation was made on the basis of ion-isotopic exchange reaction kinetics by using 131 I and 82 Br radioactive tracer isotopes. It was observed that for both the resins, the values of specific reaction rate (min -1 ), amount of ion exchanged (mmol) and initial rate of ion exchange (mmol/min) were calculated to be lower for bromide ion-isotopic exchange reaction than that for iodide ion-isotopic exchange reaction. It was observed that for iodide ion-isotopic exchange reaction under identical experimental conditions of 30.0 C, 1.000 g of ion exchange resins and 0.001 mol/L labeled iodide ion solution, the values of specific reaction rate (min -1 ), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log K d were calculated as 0.377, 0.212, 0.080 and 15.5 respectively for Dowex SBR LC resin, which was higher than 0.215, 0.144, 0.031 and 14.1 respectively as that obtained for Tulsion A23 resins. Also at a constant temperature of 30.0 C, as the concentration of labeled iodide ion solution increases from 0.001 mol/L to 0.004 mol/L, the percentage of iodide ions exchanged increases from 84.75 % to 90.20 % for Dowex SBR LC resins which was higher than increases from 57.66 % to 62.38 % obtained for Tulsion A23 resins. The identical trend was observed for the two resins during bromide ion-isotopic exchange reaction. The overall results indicate superior performance of Dowex SBR LC over Tulsion A23 resins under identical experimental conditions.

  13. The effect of loading solution and dissolution media on release of Diclofenac from ion exchange resins

    Directory of Open Access Journals (Sweden)

    "Atyabi F

    2002-07-01

    Full Text Available Drugs can be loaded on ion exchange resins in order to control their release. Loading of diclofenac sodium on the resin beads not only sustain its release but also reduce its gastrointestinal mucosal injury. In this study the effect of loading solution and concentration of diclofenac in loading solution on total amount of drug loaded on the resin beads (Amberlite IRA-900 and the release characteristic of drug in different media were examined. Results showed that diclofenac resin complex did not release their drug content in simulated gastric fluid but released it in simulated intestinal fluid independent of exposure time in acidic conditions. The effect of a number of parameters such as ionic strength and pH on the release characteristic of drug - resin complexes were also examined. Results showed that although ionic strength is an important factor, drug release is more affected by the pH of the media. NO ABSTRACT

  14. Method for loading resin beds

    International Nuclear Information System (INIS)

    Notz, K.J.; Rainey, R.H.; Greene, C.W.; Shockley, W.E.

    1978-01-01

    An improved method of preparing nuclear reactor fuel by carbonizing a uranium loaded cation exchange resin provided by contacting a H+ loaded resin with a uranyl nitrate solution deficient in nitrate, comprises providing the nitrate deficient solution by a method comprising the steps of reacting in a reaction zone maintained between about 145 to 200 0 C, a first aqueous component comprising a uranyl nitrate solution having a boiling point of at least 145 0 C with a second aqueous component to provide a gaseous phase containing HNO 3 and a reaction product comprising an aqueous uranyl nitrate solution deficient in nitrate

  15. Anion exchange purification of plutonium at lower acidities (Preprint No. CT-6)

    International Nuclear Information System (INIS)

    Kartha, P.K.S.; Ravi, S.; Achuthan, P.V.; Das, S.K.; Madhusudan, A.; Janardhanan, C.; Rao, K.S.; Ramanujam, A.; Dhumwad, R.K.

    1988-02-01

    During concentration and purification of plutonium by anion exchange, 7.2 M HNO 3 is used as loading acidity for absorbing Pu(IV). In this study, the feasibility of utilizing lower acidities like 5.2 and 6.2 M has been investigated. The results indicate that lower acidities can be used in this step if reduced resin capacities are acceptable. (author)

  16. 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.

  17. Radiochemical study of Re/W adsorption behavior on a strongly basic anion exchange resin

    International Nuclear Information System (INIS)

    Gott, Matthew D.; Missouri Univ., Columbia, MO; Ballard, Beau D.; Redman, Lindsay N.

    2014-01-01

    Rhenium-186g is a radionuclide with a high potential for therapeutic applications. It emits therapeutic β - particles accompanied by low energy γ-rays, which allows for in-vivo tracking of the radiolabeled compound and dosimetry estimates. The current reactor production pathway 185 Re(n,γ) 186g Re produces low specific activity 186g Re, thereby limiting its therapeutic application. Work is underway to develop an accelerator-based, charged particle induced production method for high specific activity 186g Re from targets of enriched 186 W. To optimize the chemical 186g Re recovery method, batch studies have been performed to characterize the adsorption behavior of Re and W on a strongly basic anion exchange resin. An in-depth physicochemical profile was developed for the interaction of Re with resin material, which showed the reaction to be endothermic and spontaneous. Basic (NaOH) and acidic (HNO 3 ) matrices were used to determine the equilibrium distribution coefficients for Re and W. The resin exhibits the best affinity for Re at slightly basic conditions and little affinity above moderately acidic concentrations. Tungsten has low affinity for the resin above moderately basic concentrations. A study was performed to examine the effect of W concentration on Re adsorption, which showed that even a high ionic WO 4 2- strength of up to 1.9 mol kg -1 does not significantly compromise ReO 4 - retention on the resin. (orig.)

  18. Application of resin in pulp technique for ion exchange separation of uranium from alkaline leachate

    International Nuclear Information System (INIS)

    Sreenivas, T.; Rajan, K.; Chakravorty, J.

    2014-01-01

    The hydrometallurgical process for the recovery of uranium from different ores uses ion exchange (IX) technique for the separation of dissolved uranium values. Conventionally, the IX process is carried out on leach solution obtained after the filtration or counter-current decantation of the leach slurries. Amongst the two types of leach pulps generated in uranium ore processing, viz acidic and alkaline, the latter one consists of predominantly fine-size pulps of higher viscosity, thus making the solid-liquid separation an arduous task. Sustained research for improvising the efficiency of various unit operations in the uranium process flowsheet have resulted in advent of new generation resins which are mechanically re-silent, posses higher exchange capacity thereby enabling separation of dissolved uranium ions from the leach pulps directly. Some of the prominent low-grade uranium ore deposits in India are hosted in acid consuming gangue matrix. These ore deposits necessitate fine grinding as well as application of alkaline leaching for the dissolution of uranium values. The leach pulps analyse 500 – 600 mg/l of U3O8 and contain total dissolved solutes (TDS) to the extent of about 50 g/l. Analysis of the characteristics of the leach pulp indicated suitability of resin-in-pulp technique for the separation of uranyl carbonate anions from the leachate. This paper describes the results of the RIP test work on alkaline leach slurry using various commercially available strong base anionic exchange resins. Parametric variation studies were conducted to establish the adsorption isotherm and sorption kinetics followed by elution of loaded uranium. Based on these results semi-continuous experiments on “carousel” mode were carried out. The results indicate superiority of gel type polystyrene based resins grafted with quaternary ammonium ion in comparison to the macro-porous resins. Semi-continuous counter-current extraction and elution tests indicated that about 98% of

  19. 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

  20. Isotope exchange reaction of tritium on precious metal catalyst based on cation-exchanged mordenite for blanket tritium recovery

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Yoshinori, E-mail: kawamura.yoshinori@jaea.go.jp [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki 311-0193 (Japan); Hayashi, Takumi [Japan Atomic Energy Agency, 2-4 Shirane Shirakata, Tokai, Ibaraki 319-1195 (Japan); Yamanishi, Toshihiko [Japan Atomic Energy Agency, 2-166 Omotedate Obuchi, Rokkasho, Aomori 039-3212 (Japan)

    2016-11-01

    Highlights: • Precious metal catalyst based on cation-exchanged mordenite was prepared. • Isotope exchange reaction between H{sub 2} and HTO on the catalyst was investigated. • The order of entire reaction is not clear, but it is the first-order reaction as for HTO. • Effect of exchanged cation may appear as the difference of the surface area of catalyst. - Abstract: It is known that the chemical forms of tritium released from a ceramic breeder blanket are hydrogen form and water form. To recover tritiated water vapor, adoption of dryer that is packed column of synthetic zeolite has been proposed. On the other hand, synthetic zeolite is often used as a support of precious metal catalyst. Such catalysts usually have a capability of hydrogen isotope exchange between gas and water vapor. If this catalyst is used to dryer, the dryer may obtain a preferable function for tritium recovery by isotopic exchange reaction. To assess such functions, reaction rate should be estimated. The results of water adsorption experiment on cation-exchanged mordenite-type zeolite suggested the possibility that state of adsorbed water varied by exchanged cation. So, in this work, precious metal catalyst based on cation-exchanged mordenite was prepared, and the reaction rate of chemical exchange between hydrogen and tritiated water was investigated under temperature range between 30 °C and 80 °C by the steady-state approximation. In the case of platinum on Na-mordenite, the reaction between gaseous hydrogen and tritiated water vapor was almost expressed as first-order reaction concerning tritiated water vapor concentration.

  1. Use of combined ion exchangers on the basis of KU-23 and KM-2p cation exchangers for purification of ammonium molybdate and tungstate solutions from phosphate, arsenate, and silicate impurities

    International Nuclear Information System (INIS)

    Blokhin, A.A.; Majorov, D.Yu.; Kopyrin, A.A.; Taushkanov, V.P.

    2002-01-01

    Using the Tracer technique ( 32 P) and elementary analysis, potentiality of using combined ionites on the basis of macroporous cation-exchange resins KU-23 or KM-2p and hydrated zirconium oxide for purification of concentrated solutions of ammonium molybdate and tungstate from phosphate-, arsenate-, and silicate-ions impurities was studied. High selectivity of the combined ionites towards impurity ions was ascertained, which permits reducing the content of impurities by a factor of 50-100 compared with the initial one [ru

  2. Evaluation of some anionic exchange resins as potential tablet ...

    African Journals Online (AJOL)

    The effect of resin concentration and compression force on the properties of tablets using the selected resin was investigated. In addition, the disintegrant efficacy of the selected resin in the tablet formulations containing either a basic drug, e.g., dextromethorphan hydrobromide (DMP), or an acidic drug, e.g., diclofenac ...

  3. Study of mechanical and physicochemical properties of cementated spent ion-exchange-resins

    International Nuclear Information System (INIS)

    Patek, P.

    1981-09-01

    As first part of a study on the possibilities, to immobilize spent ion exchange resins, for final disposal, the dependence of compressive strength from the composition of cement - resin mixtures was detected. Powdered resins, bead resins and ashes from the incinerator plant and several cement brands were examinated. As result an area was defined in the three-phase diagram of cement, resins and water, in which the following leach tests will be performed. (author)

  4. Ion Exchange Properties of a Terpolymer Resin Derived from 2, 4-Dihydroxybenzaldehyde, Oxamide and Formaldehyde

    Directory of Open Access Journals (Sweden)

    M. V. Tarase

    2009-01-01

    Full Text Available Terpolymer resins (2,4-DHBOF were synthesized by the condensation of 2,4-dihydroxybenzaldehyde and oxamide with formaldehyde in the presence of hydrochloric acid as catalyst, proved to be selective chelation ion exchange terpolymer resins for certain metals. Chelation ion exchange properties of these polymers were studied for Fe+3, Cu+2, Hg+2, Cd+2, Co+2, Zn+2, Ni+2 and Pb+2 ions. A batch equilibrium method was employed in the study of the selectivity of the distribution of a given metal ions between the polymer sample and a solution containing the metal ion. The study was carried out over a wide pH range and in a media of various ionic strengths. The polymer showed a higher selectivity for Fe+3, Cd+2 and Co+2 ions than for Cu+2, Hg+2, Zn+2, Ni+2 and Pb+2 ions.

  5. 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.)

  6. Casting granular ion exchange resins with medium-active waste in cement

    International Nuclear Information System (INIS)

    Beijer, O.

    1980-01-01

    Medium active waste from nuclear power stations in Sweden is trapped in granular ion exchange resins. The resin is mixed with cement paste and cast in a concrete shell which is cubic and has an edge dimension of 1.2 m. In some cases the ion exchange cement mortar has cracked. The report presents laboratory sutdies of the properties of the ion exchange resin and the mortar. Also the leaching of the moulds has been investigated. It was shown that a mixture with a water cement ratio higher than about 0.5 swells considerably during the first weeks after casting. The diffusion constant for cesium 137 has been determined at 3.10 -4 cm 2 /24-hour period in conjunction with exposure of the mould and mortar to sea water. The Swedish language report has 400 pages with 90 figures and 30 tables. (author)

  7. Measurement of cation exchange capacity (CEC) on natural zeolite by percolation method

    Science.gov (United States)

    Wiyantoko, Bayu; Rahmah, Nafisa

    2017-12-01

    The cation exchange capacity (CEC)measurement has been carried out in natural zeolite by percolation method. The natural zeolite samples used for cation exchange capacity measurement were activated beforehand with physical activation and chemical activation. The physically activated zeolite was done by calcination process at 600 °C for 4 hours. The natural zeolite was activated chemically by using sodium hydroxide by refluxing process at 60-80 °C for 3 hours. In summary, cation exchange capacity (CEC) determination was performed by percolation, distillation and titration processes. Based on the measurement that has been done, the exchange rate results from physical activated and chemical activated of natural zeolite were 181.90cmol (+)/kg and 901.49cmol (+)/kg respectively.

  8. 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

  9. Restructuring of a peat in interaction with multivalent cations: effect of cation type and aging time.

    Science.gov (United States)

    Kunhi Mouvenchery, Yamuna; Jaeger, Alexander; Aquino, Adelia J A; Tunega, Daniel; Diehl, Dörte; Bertmer, Marko; Schaumann, Gabriele Ellen

    2013-01-01

    It is assumed to be common knowledge that multivalent cations cross-link soil organic matter (SOM) molecules via cation bridges (CaB). The concept has not been explicitly demonstrated in solid SOM by targeted experiments, yet. Therefore, the requirements for and characteristics of CaB remain unidentified. In this study, a combined experimental and molecular modeling approach was adopted to investigate the interaction of cations on a peat OM from physicochemical perspective. Before treatment with salt solutions of Al(3+), Ca(2+) or Na(+), respectively, the original exchangeable cations were removed using cation exchange resin. Cation treatment was conducted at two different values of pH prior to adjusting pH to 4.1. Cation sorption is slower (>2 h) than deprotonation of functional groups (cation addition and decreased with increasing cation valency. Sorption coefficients were similar for all cations and at both pH. This contradicts the general expectations for electrostatic interactions, suggesting that not only the interaction chemistry but also spatial distribution of functional groups in OM determines binding of cations in this peat. The reaction of contact angle, matrix rigidity due to water molecule bridges (WaMB) and molecular mobility of water (NMR analysis) suggested that cross-linking via CaB has low relevance in this peat. This unexpected finding is probably due to the low cation exchange capacity, resulting in low abundance of charged functionalities. Molecular modeling demonstrates that large average distances between functionalities (∼3 nm in this peat) cannot be bridged by CaB-WaMB associations. However, aging strongly increased matrix rigidity, suggesting successive increase of WaMB size to connect functionalities and thus increasing degree of cross-linking by CaB-WaMB associations. Results thus demonstrated that the physicochemical structure of OM is decisive for CaB and aging-induced structural reorganisation can enhance cross-link formation.

  10. Fractionation of equine antivenom using caprylic acid precipitation in combination with cationic ion-exchange chromatography.

    Science.gov (United States)

    Raweerith, Rutai; Ratanabanangkoon, Kavi

    2003-11-01

    A combined process of caprylic acid (CA) precipitation and ion-exchange chromatography on SP-Sepharose was studied as a means to fractionate pepsin-digested horse antivenom F(ab')(2) antibody. In the CA precipitation, the optimal concentration for fractionation of F(ab')(2) from pepsin-digested horse plasma was 2%, in which 89.61% of F(ab')(2) antibody activity was recovered in the supernatant with 1.5-fold purification. A significant amount of pepsin was not precipitated and remained active under these conditions. An analytical cation exchanger Protein-Pak SP 8HR HPLC column was tested to establish optimal conditions for the effective separation of IgG, albumin, pepsin and CA from the F(ab')(2) product. From these results, the supernatant from CA precipitation of pepsin-digested plasma was subjected to a SP-Sepharose column chromatography using a linear salt gradient. With stepwise elution, a peak containing F(ab')(2) antibody could be obtained by elution with 0.25 M NaCl. The total recovery of antibody was 65.56% with 2.91-fold purification, which was higher than that achieved by ammonium sulfate precipitation. This process simultaneously and effectively removed residual pepsin, high molecular weight aggregates and CA in the final F(ab')(2) product, and should be suitable for large-scale fractionation of therapeutic equine antivenoms.

  11. 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)

  12. Homogeneous cation exchange membrane by radiation grafting

    International Nuclear Information System (INIS)

    Kolhe, Shailesh M.; G, Agathian; Ashok Kumar

    2001-01-01

    Preparation of a strong cation exchange membrane by radiation grafting of styrene on to polyethylene (LDPE) film by mutual irradiation technique in the presence of air followed by sulfonation is described. The grafting has been carried out in the presence of air and without any additive. Low dose rate has been seen to facilitate the grafting. Further higher the grafting percentage more is the exchange capacity. The addition of a swelling agent during the sulfonation helped in achieving the high exchange capacity. The TGA-MASS analysis confirmed the grafting and the sulfonation. (author)

  13. 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.

  14. Recovery process for electroless plating baths

    Science.gov (United States)

    Anderson, Roger W.; Neff, Wayne A.

    1992-01-01

    A process for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO.sub.3. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse. The plating metal can be removed from the exchanger with sulfuric acid or with the filtrate from the magnesium phosphite precipitation forming a sulfate of the plating metal for reuse. The process is illustrated as applied to processing electroless nickel plating baths.

  15. The load and release characteristics on a strong cationic ion-exchange fiber: kinetics, thermodynamics, and influences.

    Science.gov (United States)

    Yuan, Jing; Gao, Yanan; Wang, Xinyu; Liu, Hongzhuo; Che, Xin; Xu, Lu; Yang, Yang; Wang, Qifang; Wang, Yan; Li, Sanming

    2014-01-01

    Ion-exchange fibers were different from conventional ion-exchange resins in their non-cross-linked structure. The exchange was located on the surface of the framework, and the transport resistance reduced significantly, which might mean that the exchange is controlled by an ionic reaction instead of diffusion. Therefore, this work aimed to investigate the load and release characteristics of five model drugs with the strong cationic ion-exchange fiber ZB-1. Drugs were loaded using a batch process and released in United States Pharmacopoeia (USP) dissolution apparatus 2. Opposing exchange kinetics, suitable for the special structure of the fiber, were developed for describing the exchange process with the help of thermodynamics, which illustrated that the load was controlled by an ionic reaction. The molecular weight was the most important factor to influence the drug load and release rate. Strong alkalinity and rings in the molecular structures made the affinity between the drug and fiber strong, while logP did not cause any profound differences. The drug-fiber complexes exhibited sustained release. Different kinds and concentrations of counter ions or different amounts of drug-fiber complexes in the release medium affected the release behavior, while the pH value was independent of it. The groundwork for in-depth exploration and further application of ion-exchange fibers has been laid.

  16. Kinetics of ion exchange in the chelating resin Dowex A-1

    International Nuclear Information System (INIS)

    Matsuzuru, Hideo; Wadachi, Yoshiki

    1975-01-01

    The kinetics of ion exchanges of Ag + , Zn 2+ and Cr 3+ at extremely low concentrations on the chelating resin Dowex A-1 has been studied by means of finite volume method. The rate of exchanges for both Ag + and Zn 2+ is dependent on the ionic strength, particle size of the resin and reaction temperature. At higher ionic strength (0.1 - 0.05) the kinetics is controlled by particle diffusion, whereas at lower ionic one (0.01 - 0.001) film diffusion is predominant. The apparent activation energy obtained is 3.84 kcal/mol for Ag + and 3.91 kcal/mol for Zn 2+ . The exchange rate of Cr 3+ obeys a first-order rate equation independent of the ionic strength and particle size of the resin. The apparent activation energy is 15.5 kcal/mol. These results support the view that the rate-determining step of this reaction is chelate formation reaction. (auth.)

  17. Process for the separation of proteins from acid whey

    Energy Technology Data Exchange (ETDEWEB)

    Mirabel, B

    1980-01-01

    Acid whey from cheese or casein manufacture (pH less than 4.6) and containing about 5.2 g protein/l is passed through a cation exchange resin (of silica coated with a copolymer of styrene/vinyltriethoxysilane carrying SO/sub 3/H functional groups). The proteins adsorbed on the resin (alpha-lactalbumin, beta-lactoglobulin, serum albumin and immunoglobulins) are eluated with an 0.1 M ammonia solution, concentrated under vacuum and freeze-dried, obtaining a final product with 88% undenatured protein. The products are for use in the food and pharmaceutical industries and for dietetic and veterinary purposes.

  18. Dehydrating process experiment on spent ion-exchange resin sludge by Funda Filter

    International Nuclear Information System (INIS)

    Hasegawa, Tatsuo; Ishino, Kazuyuki

    1977-01-01

    In nuclear power plants, Funda Filters are employed to dehydrate spent powdery ion-exchange resin sludge. The Funda Filter is very effective for eliminating small rust components contained in spent powdery resin slurry; however, in the drying process, the complete drying of spent powdery resin is very difficult because the filter cake of resin on the horizontal filter leaf is likely to crack and let out steam and hot air through the cracks. This paper deals with the results of experiments conducted to clarify the detailed phenomena of dehydration so the above problem could be solved. The above experiments were made on the precoating and drying of granular ion-exchange resin slurry that had not yet been put to practical use. The experiments were composed of one fundamental and one operational stage. In the fundamental experiment, the dehydration properties and dehydration mechanism of resins were made clear, and the most effective operational method was established through the operational experiments conducted using large-scale Funda Filter test equipment under various conditions. (auth.)

  19. Radiochemical study of Re/W adsorption behavior on a strongly basic anion exchange resin

    Energy Technology Data Exchange (ETDEWEB)

    Gott, Matthew D. [Los Alamos National Laboratory, Los Alamos, NM (United States). Chemistry Div.; Missouri Univ., Columbia, MO (United States). Dept. of Chemistry; Ballard, Beau D.; Redman, Lindsay N. [Los Alamos National Laboratory, Los Alamos, NM (United States). Chemistry Div.; and others

    2014-07-01

    Rhenium-186g is a radionuclide with a high potential for therapeutic applications. It emits therapeutic β{sup -} particles accompanied by low energy γ-rays, which allows for in-vivo tracking of the radiolabeled compound and dosimetry estimates. The current reactor production pathway {sup 185}Re(n,γ){sup 186g}Re produces low specific activity {sup 186g}Re, thereby limiting its therapeutic application. Work is underway to develop an accelerator-based, charged particle induced production method for high specific activity {sup 186g}Re from targets of enriched {sup 186}W. To optimize the chemical {sup 186g}Re recovery method, batch studies have been performed to characterize the adsorption behavior of Re and W on a strongly basic anion exchange resin. An in-depth physicochemical profile was developed for the interaction of Re with resin material, which showed the reaction to be endothermic and spontaneous. Basic (NaOH) and acidic (HNO{sub 3}) matrices were used to determine the equilibrium distribution coefficients for Re and W. The resin exhibits the best affinity for Re at slightly basic conditions and little affinity above moderately acidic concentrations. Tungsten has low affinity for the resin above moderately basic concentrations. A study was performed to examine the effect of W concentration on Re adsorption, which showed that even a high ionic WO{sub 4}{sup 2-} strength of up to 1.9 mol kg{sup -1} does not significantly compromise ReO{sub 4}{sup -} retention on the resin. (orig.)

  20. 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.

  1. 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

  2. The ion-exchange obtaining of high purity samarium oxide

    International Nuclear Information System (INIS)

    Brzyska, W.; Soltysiak, I.; Cygan, J.

    1987-01-01

    The use of lactic acid - EDTA mixture as an eluent for the obtaining of high purity samarium oxide was studied. The studies were carried out at room temperature on cation exchange resin Wofatit KPS X 8. The best results were obtained for lactic acid (0,26 mol/dm 3 ) - EDTA (0,013 mol/dm 3 ) mixture at pH 3,3. As the result of 57% samarium concentrate elution with column load 1:3 and flow rate 0,4 cm/min, over 99% pure samarium oxide with 73% yield has been obtained. The yield of spectrally pure Sm 2 O 3 exceeded 45%. (author)

  3. Application of a weak base anion exchange resin for recovery of uranium at Uravan, Colorado, U.S.A

    International Nuclear Information System (INIS)

    Gardner, N.E.; Kunin, R.

    1976-01-01

    Resin ion-exchange technology has been used to recover uranium at the Uravan, Colorado plant for over 18 years; however, since the end of U.S. Atomic Energy Commission purchase of U 3 O 8 concentrate in 1970, it has become necessary to develop techniques for upgrading the product to meet the more stringent specifications of private sales. The standard gel type quaternary ammonium anion exchange resin had been used previously. The development of the tertiary amine anion exchange resin, Amberlite XE-299, led to an experimental program of laboratory and pilot plant work to evaluate the resin on actual plant solutions. General information on ion-exchange resin structure and chemistry is discussed. Summary data of specific test work on loading the resin, various elution schemes, resin regeneration and product purity from the pilot plant tests and comments on actual plant operation using Amberlite XE-299 resin are presented. (author)

  4. Rejuvenation of the anion exchanger used for uranium recovery

    International Nuclear Information System (INIS)

    Yan, T.-Y.; Espenscheid, W.F.

    1986-01-01

    The present invention is directed to improving the performance of strong base anionic exchange resins used in uranium recovery that exhibit an undesirable decrease in loading capacity and in total exchange capacity. The invention comprises treating an anionic exchange resin to remove physically adsorbed and occluded fouling agents and to remove poisons which may be chemically bound to active ion groups on the resin. The process involves treating the resin, after the uranium ion exchange stage, with an alkaline carbonate solution, preferably treating the resin with an acid eluant first. The acid treatment dissolves insoluble fouling agents which are physically occluded or adsorbed by the resin and that the weak base treatment augments that result and probably removes poisons which are physically or chemically bound to the resin

  5. Studies of Vitrification of Ion-Exchange Resins. A Joint USA-Argentina Collaborative Work

    International Nuclear Information System (INIS)

    Hutson, N.D.; Herman, C.A.; Zamecnik, J.R.; Sundaram, S.K.; Perez, J.M.; Hoeffner, S.L.; Russo, D.O.; Sterba, M.

    2003-01-01

    Under the Science and Technology Implementing Arrangement for Cooperation on Radioactive and Mixed Waste Management (JCCRM), the U.S.Department of Energy (DOE) is helping to transfer waste treatment technology to international atomic energy commissions.As part of the JCCRM, DOE has established a collaborative research agreement with the Comision Nacional de Energia Atomica (Cnea).The Cnea is investigating treatment and disposal options for organic ion exchange resins currently stored at two nuclear power plants in the Republic of Argentina.The major hazards of the ion exchange resins are their organic composition and the contaminants that are present on the resins after purification processes.The principal contaminants are usually the radioactive species that are removed.For these studies, actual non-radioactive resins from Argentina's Embalse and Atucha plants were tested.The glass produced during the runs was durable was measured by the Product Consistency Test (PCT).The product had a predictable, mostly amorphous composition throughout the demonstrations; though there was some evidence of the formation of clinopyroxene crystals.The immobilized product represented an approximately 70% volume reduction from the simulated Argentine ion exchange resin (i.e., a reduction from the volume of as-stored wet resin to the volume of the ultimate borosilicate glass product).For all runs, the radioactive surrogate retention was near 100%

  6. 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

  7. Development of novel ion-exchange membranes for electrodialysis of seawater by electron-beam-induced graft polymerization (4). Polymeric structures of cation-exchange membranes based on nylon-6 film

    International Nuclear Information System (INIS)

    Miyazawa, Tadashi; Asari, Yuki; Miyoshi, Kazuyoshi; Umeno, Daisuke; Saito, Kyoichi; Nagatani, Takeshi; Yoshikawa, Naohito; Motokawa, Ryuhei; Koizumi, Satoshi

    2010-01-01

    Cation-exchange membranes containing a sulfonic acid group were prepared by electron-beam-induced graft polymerization of sodium styrene sulfonate (SSS) onto a nylon-6 film with a thickness of 25 μm. The lamella sizes and lamella-to-lamella intervals of the resultant cation-exchange membranes (SSS membranes) were evaluated by X-ray diffraction (XRD) analysis and small-angle neutron scattering (SANS), respectively. With increasing degrees of grafting, the lamella size decreased, whereas the lamella-to-lamella interval increased. This can be explained by that the poly-SSS chain grafted to the periphery of the lamella of nylon 6 partially destroys the lamella and invades the amorphous domain among the lamella. The SSS membrane with a degree of grafting of 150% exhibited a similar performance in the electrodialysis of 0.5 M sodium chloride as a current cation-exchange membrane and possessed the lamella sizes and lamella-to-lamella intervals of 7.6 and 13 nm, respectively. (author)

  8. Selective Facet Reactivity During Cation Exchange in Cadmium Sulfide Nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Sadtler, Bryce; Demchenko, Denis; Zheng, Haimei; Hughes, Steven; Merkle, Maxwell; Dahmen, Ulrich; Wang, Lin-Wang; Alivisatos, A. Paul

    2008-12-18

    The partial transformation of ionic nanocrystals through cation exchange has been used to synthesize nanocrystal heterostructures. We demonstrate that the selectivity for cation exchange to take place at different facets of the nanocrystal plays an important role in determining the resulting morphology of the binary heterostructure. In the case of copper I (Cu+) cation exchange in cadmium sulfide (CdS) nanorods, the reaction starts preferentially at the ends of the nanorods such that copper sulfide (Cu2S) grows inwards from either end. The resulting morphology is very different from the striped pattern obtained in our previous studies of silver I (Ag+) exchange in CdS nanorods where non-selective nucleation of silver sulfide (Ag2S) occurs. From interface formation energies calculated for several models of epitaxialconnections between CdS and Cu2S or Ag2S, we infer the relative stability of each interface during the nucleation and growth of Cu2S or Ag2S within the CdS nanorods. The epitaxial connections of Cu2S to the end facets of CdS nanorods minimize the formation energy, making these interfaces stable throughout the exchange reaction. However, as the two end facets of wurtzite CdS nanorods are crystallographically nonequivalent, asymmetric heterostructures can be produced.

  9. Technological aspects of vegetable oils epoxidation in the presence of ion exchange resins: a review

    Directory of Open Access Journals (Sweden)

    Milchert Eugeniusz

    2016-09-01

    Full Text Available A review paper of the technology basics of vegetable oils epoxidation by means of peracetic or performic acid in the presence of acidic ion exchange resins has been presented. The influence of the following parameters: temperature, molar ratio of acetic acid and hydrogen peroxide to ethylenic unsaturation, catalyst loading, stirring intensity and the reaction time on a conversion of ethylenic unsaturation, the relative percentage conversion to oxirane and the iodine number was discussed. Optimal technological parameters, mechanism of epoxidation by carboxylic peracids and the possibilities of catalyst recycling have been also discussed. This review paper shows the application of epoxidized oils.

  10. Measurement of acid dissociation constants of weak acids by cation exchange and conductometry

    Energy Technology Data Exchange (ETDEWEB)

    Dasgupta, P.K.; Nara, Osamu (Texas Tech Univ., Lubbock (USA))

    1990-06-01

    A simple strategy is presented for the determination of acid dissociation constants based on the measurement of conductance of a known concentration of the acid and/or the conductance of a solution of its fully or partially neutralized alkali-metal salts. For an n-protic acid, 2n conductance measurements are minimally necessary. In the simplest case of a typical monoprotic acid, the conductance of its alkali salt solution is measured before and after passage through an H{sup +}-form exchanger. From these data both the pK{sub a} of the acid and the equivalent conductance of the anion can be computed. The underlying equations are rigorously solved for monoprotic acids and some diprotic acid systems. For other diprotic and multiprotic acid systems, initial estimates are obtained by making approximations; the complete data set is then subjected to multiparametric fitting. The method does not require pH measurements; conductance can generally be measured accurately at low enough ionic strengths to obviate the need for major activity correction. Several experimental measurements are presented and excellent agreement with literature pK{sub a} values is observed. The reliability of the equivalent conductance values computed in this fashion is limited, however.

  11. Uranium recovery and uranium remove from acid mine waters by ion exchange resin; Remocao e recuperacao de uranio de aguas acidas de mina com resina de troca ionica

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, Marcos R.L. [Comissao Nacional de Energia Nuclear (CNEN), Pocos de Caldas, MG (Brazil). Coordenacao do Laborarorio; Fatibello Filho, Orlando [Sao Carlos Univ., SP (Brazil). Dept. de Quimica

    1999-11-01

    Ion exchange using resins is one of few processes capable of reducing contaminants in effluents to very low levels according to environmental legislation. In this study the process was used to remove and recovery uranium from acid mine waters at Pocos de Caldas-MG Uranium Mining and Milling Plant. The presence of pyrite in the waste rock piles, resulting acid drainage with several pollutants. Including uranium ranging from 6 to 14 mg/l, as sulfate complex, that can be removed by an anionic exchanger. Studies of uranium sorption without treatment, and with lime pretreatment of water to precipitate the iron and recovery uranium as commercial product, are presented. Uranium elution was done with NaCl solutions. Saline concentration and retention time were the parameters studied. the uranium decontaminations level in the effluents from acid mine water was 94%. (author) 10 refs., 6 tabs., 3 figs.

  12. 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

  13. Identification of amino acids in Securigera securidaca, a popular medicinal herb in Iranian folk medicine

    OpenAIRE

    S.E. Sadat-Ebrahimi; M. Hassanpoor Mir; G.R. Amin; H. Hajimehdipoor

    2014-01-01

    Securigera securidaca (L.) Degen & Dorfl grows in different parts of Iran. The seeds of the species are used in Iranian folk medicine as an anti-diabetic agent. Many studies have established hypoglycemic effects of amino acids and in the present investigation, amino acids of Securigera securidaca seeds have been evaluated. The ground seeds were extracted using petroleum ether, hot ethanol and ethanol 50%, respectively. ethanol 50% extract was chromatographed over cation exchanging resin and t...

  14. Enhanced biocatalytic production of L-cysteine by Pseudomonas sp. B-3 with in situ product removal using ion-exchange resin.

    Science.gov (United States)

    Wang, Pu; He, Jun-Yao; Yin, Jiang-Feng

    2015-03-01

    Bioconversion of DL-2-amino-Δ(2)-thiazoline-4-carboxylic acid (DL-ATC) catalyzed by whole cells of Pseudomonas sp. was successfully applied for the production of L-cysteine. It was found, however, like most whole-cell biocatalytic processes, the accumulated L-cysteine produced obvious inhibition to the activity of biocatalyst and reduced the yield. To improve L-cysteine productivity, an anion exchange-based in situ product removal (ISPR) approach was developed. Several anion-exchange resins were tested to select a suitable adsorbent used in the bioconversion of DL-ATC for the in situ removal of L-cysteine. The strong basic anion-exchange resin 201 × 7 exhibited the highest adsorption capacity for L-cysteine and low adsorption for DL-ATC, which is a favorable option. With in situ addition of 60 g L(-1) resin 201 × 7, the product inhibition can be reduced significantly and 200 mmol L(-1) of DL-ATC was converted to L-cysteine with 90.4 % of yield and 28.6 mmol L(-1 )h(-1) of volumetric productivity. Compared to the bioconversion without the addition of resin, the volumetric productivity of L-cysteine was improved by 2.27-fold using ISPR method.

  15. Studies on resin degradation products encountered during purification of plutonium by anion exchange

    International Nuclear Information System (INIS)

    Ramanujam, A.; Dhami, P.S.; Gopalakrishnan, V.; Dhumwad, R.K.

    1991-01-01

    Among the methods available for the purification of plutonium in Purex process, anion exchange method offers several advantages. However, on repeated use, the resin gets degraded due to thermal, radiolytic and chemical attacks resulting in chemical as well as physical damage. Frequently, plutonium product eluted from such resin contains significant quantities of white precipitates. A few anion exchange resins were leached with 8 M HNO 3 at 60-80degC and the resin degradation products (RDP) in the leach-extract were found to give similar precipitates with tetravalent metal ions like Pu(IV), Th(IV) etc. Tetra propyl ammonium hydroxide in 8 M HNO 3 (TPAN) also gave a white precipitate with plutonium similar to the one found in the elution streams. The results indicate that delinked quaternary ammonium functional groups might be responsible for the formation of precipitate. The characteristics of precipitates Th-RDP, Th-TPAN and that isolated from elution stream have been investigated. In a separate study a tentative formula for Th-RDP compound is proposed. The influence of RDP on the extraction of plutonium and other components in Purex process was studied and it was found that RDP complexes metal ions thus marginally affecting the kd values. A spectrophotometric method has been standardised to monitor the extent of degradation of anion exchange resins which is based on the ability of RDP to reduce the colour intensity of Th-thoron complex. This technique can be used to study the stability of the anion exchange resins. (author). 8 refs., 8 tabs., 5 figs.,

  16. Gas chromatographic determination of organic acids from fruit juices by combined resin mediated methylation and extraction in supercritical carbon dioxide.

    Science.gov (United States)

    Barden, T J; Croft, M Y; Murby, E J; Wells, R J

    1997-10-17

    A procedure in which anionic analytes, trapped on ion exchange resin, are simultaneously methylated and released using methyl iodide in either supercritical carbon dioxide or acetonitrile has been extended to polyfunctional organic acids. The combined SFE methylation of fruit juice acids trapped onto ion exchange resin proceeds in good yield producing the methyl esters of fumaric, succinic, malic, tartaric, isocitric and citric acids which are readily separated by GC. Using this procedure low concentrations of one acid can be detected and quantitated in the presence of very high concentrations of another. This new method detects tartaric acid at levels of 10 ppm in juices containing 10,000 ppm citric acid. Quantitation was performed either by using GC-FID with triethyl citrate or diethyl tartrate as internal standards or with the element specific calibration capability of the GC-AED. A simple new technique for the determination of citric/isocitric acid ratio is now available. Also, in contrast to HPLC methods, the identity of an analyte is readily confirmed by GC-MS.

  17. Separation of bismuth from gram amounts of thallium and silver by cation-exchange chromatography in nitric acid.

    Science.gov (United States)

    Meintjies, E; Strelow, F W; Victor, A H

    1987-04-01

    Traces and small amounts of bismuth can be separated from gram amounts of thallium and silver by successively eluting these elements with 0.3M and 0.6M nitric acid from a column containing 13 ml (3 g) of AG50W-X4, a cation-exchanger (100-200 mesh particle size) with low cross-linking. Bismuth is retained and can be eluted with 0.2M hydrobromic acid containing 20% v/v acetone, leaving many other trace elements absorbed. Elution of thallium is quite sharp, but silver shows a small amount of tailing (less than 1 gmg/ml silver in the eluate) when gram amounts are present, between 20 and 80 mug of silver appearing in the bismuth fraction. Relevant elution curves and results for the analysis of synthetic mixtures containing between 50 mug and 10 mg of bismuth and up to more than 1 g of thallium and silver are presented, as well as results for bismuth in a sample of thallium metal and in Merck thallium(I) carbonate. As little as 0.01 ppm of bismuth can be determined when the separation is combined with electrothermal atomic-absorption spectrometry.

  18. Boron removal from aqueous solutions by ion-exchange resin: Column sorption-elution studies

    International Nuclear Information System (INIS)

    Koese, T. Ennil; Oztuerk, Nese

    2008-01-01

    A column sorption-elution study was carried out by using a strong base anion-exchange resin (Dowex 2 x 8) for the removal of boron from aqueous solutions. The breakthrough curve was obtained as a function of feed flow rate and the total and breakthrough capacity values of the resin were calculated. The boron on the resin was quantitatively eluted with 0.5 M HCl solution at different flow rates. Three consecutive sorption-elution-washing-regeneration-washing cycles were applied to the resin in order to investigate the reusability of the ion-exchange resin. Total capacity values remained almost the same after three sorption-elution-regeneration cycles. The Thomas and the Yoon-Nelson models were applied to experimental data to predict the breakthrough curves and to determine the characteristic column parameters required for process design. The results proved that the models would describe the breakthrough curves well

  19. Cycling of acid and base cations in deciduous stands of Huntington Forest, New York, and Turkey Lakes, Ontario

    Energy Technology Data Exchange (ETDEWEB)

    Foster, N W; Morrison, I K [Forestry Canada, Sault Ste. Marie, ON (Canada); Mitchell, M J [State Univ. of New York, Syracuse, NY (USA); Shepard, J P [National Council of the Paper Industry for Air and Stream Improvement, Gainesville, FL (USA)

    1992-01-01

    Annual nutrient fluxes within two forests exposed to acidic deposition were compared for a 1-year period. Calcium (Ca{sup 2+}) was the dominant cation in throughfall and soil solutions from tolerant hardwood dominated Spodosols (Podzols) at both Huntington Forest (HF), New York, and the Turkey Lakes watershed (TLW), Ontario. There was a net annual export of Ca{sup 2+} and Mg{sup 2+} from the TLW soil, whereas base cation inputs in precipitation equalled outputs at HF. In 1986, leaching losses of base cations were five times greater at TLW than at HF. A higher percentage of the base cation reserves was leached from the soil at TLW (5%) than at HF (1%). Relative to throughfall, aluminum concentrations increased in forest-floor and mineral-soil solutions, especially at HF. The TLW soil appears more sensitive to soil acidification. Deposited atmospheric acidity, however, was small in comparison with native soil acidity (total and exchangeable) and the reserves of base cations in each soil. Soil acidity and base saturation, therefore, are likely only to change slowly. 57 refs., 1 fig., 5 tabs.

  20. Cation Exchange Capacity of Biochar: An urgent method modification

    Science.gov (United States)

    Munera, Jose; Martinsen, Vegard; Mulder, Jan; Tau Strand, Line; Cornelissen, Gerard

    2017-04-01

    A better understanding of the cation exchange capacity (CEC) values of biochar and its acid neutralizing capacity (ANC) is crucial when tailoring a single biochar for a particular soil and crop. Literature values for the CEC of biochar are surprisingly variable, commonly ranging from 5 to 50 cmol+/Kg even as high as 69 to 204 cmol+/Kg and often poorly reproducible, suggesting methodological problems. Ashes and very fine pores in biochar may complicate the analysis and thus compromise the results. Here, we modify and critically assess different steps in a common method for CEC determination in biochar and investigate how the measured CEC may be affected by slow cation diffusion from micro-pores. We modified the existing ammonium acetate (NH4-OAc) method (buffered at pH 7), based on displaced ammonium (NH4+) in potassium chloride (KCl) extracts after removing excess NH4-OAc with alcohol in batch mode. We used pigeon pea biochar (produced at 350 ˚C; particle size 0.5mm to 2mm) to develop the method and we tested its reproducibility in biochars with different ANC. The biochar sample (1.00g) was pH-adjusted to 7 after 2 days of equilibration, using hydrochloric acid (HCl), and washed with water until the conductivity of the water was modified method were highly reproducible and that 1 day shaking with NH4OAc and KCl is enough to saturate the exchange sites with NH4+ and subsequently with K+. The biochar to NH4OAc solution ratio did not affect the measured CEC. Three washings with at least 15 ml alcohol are required to remove excess NH4-OAc. We found the CEC of biochar with the displacement method from pigeon pea, corncob, rice husk and cacao shell to be 26.4(±0.3), 19.2(±0.5), 20.5(±0.4), 46.5±(0.2) cmol+/Kg, respectively. The selected batch experiment allows a large sample throughput, less laboratory equipment is needed and shaking ensures better contact between the extracting solution and the exchange sites.

  1. Separation of Mn(II) in presence of Al(III) in acid drainage from an Uranium mine with the use of chelating resins

    International Nuclear Information System (INIS)

    Soares, Eliane Pavesi B.; Gomes, Viviane T.; Vaitsman, Delmo S.

    2011-01-01

    The acid drainage of Osamu Utsumi mine is the main environmental impact from mining activities in Pocos de Caldas - MG - Brazil. The water produced in this process is characterized by high acidity and heavy metal concentration. To minimize this environmental impact, new technologies directed towards treatment of acid drainage of mine (ADM) have been studied. However, due to the presence of Al 3+ (which has a high charge) in the ADM, these resins get quickly saturated, preventing stripping of divalent cations like Mn 2+ . This study proposes the synthesis of chelating resins that provide preferential retention of Mn 2+ instead of Al 3+ . It was synthesized resins functionalized with amidoxime and dithiocarbamate. The capacity of retention of Mn 2+ e Al 3+ ions at different pH values was assessed for each resin. The stripping of Mn 2+ at 2, 3 and 4 (pH ADM range) by studied resins was not preferential for Mn 2+ in relation to Al 3+ , probably due to the strong electrostatic interaction between this last type of high charge density and the active sites from extractor agents and resins. However at pH 6 (stated by environmental norms for liquid effluents discharge) the synthesized resins had a good retention capacity for Mn 2+ . So it is proposed that the extraction technique using chelating resins could be employed to strip Mn 2+ from ADM at pH 6,0, since at this condition , Al 3+ is precipitated as Al(OH) 3 . (author)

  2. Catalytic hydrodechlorination of triclosan using a new class of anion-exchange-resin supported palladium catalysts.

    Science.gov (United States)

    Han, Bing; Liu, Wen; Li, Jingwen; Wang, Jin; Zhao, Dongye; Xu, Rui; Lin, Zhang

    2017-09-01

    We prepared a new class of anion-exchange-resin supported Pd catalysts for efficient hydrodechlorination of triclosan in water. The catalysts were prepared through an initial ion-exchange uptake of PdCl 4 2- and subsequent reduction of Pd(II) to Pd(0) nanoparticles at ambient temperature. Two standard strong-base anion exchange resins (IRA-900 and IRA-958) with different matrices (polystyrene and polyacrylic) were chosen as the supports. SEM and TEM images showed that Pd(0) nanoparticles were evenly attached on the resin surface with a mean size of 3-5 nm. The resin supported Pd catalysts (Pd@IRA-900 and Pd@IRA-958) were able to facilitate rapid and complete hydrodechlorination of triclosan. At a Pd loading of 2.0 wt.%, the observed pseudo first-order rate constant (k obs ) was 1.25 ± 0.06 and 1.6 ± 0.1 L/g/min for Pd@IRA-900 and Pd@IRA-958, respectively. The catalysts were more resistant to Cl - poisoning and natural organic matter fouling than other supported-Pd catalysts. The presence of 10 mM NaCl suppressed the k obs value by 31% and 23% for Pd@IRA-900 and Pd@IRA-958, whereas the presence of humic acid at 30 mg/L as TOC lowered the rates by 28% and 27%, respectively. The better performance of Pd@IRA-958 was attributed to the polymeric matrix properties (i.e., hydrophobicity, pore size, and surface area) as well as Pd particle size. GC/MS analyses indicated that very low concentrations of chlorinated intermediates were detected in the early stage of the hydrodechlorination process, with 2-phenoxyphenol being the main byproduct. The catalysts can be repeatedly used in multiple operations without significant bleeding. The catalysts eliminate the need for calcination in preparing conventional supported catalysts, and the resin supports conveniently facilitate control of Pd loading and material properties. Copyright © 2017 Elsevier Ltd. All rights reserved.

  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. Cobalt 60 cation exchange with mexican clays

    International Nuclear Information System (INIS)

    Nava Galve, R.G.

    1993-01-01

    Mexican clays can be used to remove radioactive elements from contaminated aqueous solutions. Cation exchange experiments were performed with 60 Co radioactive solution. In the present work the effect of contact time on the sorption of Co 2+ was studied. The contact time in hydrated montmorillonite was from 5 to 120 minutes and in dehydrated montmorillonite 5 to 1400 minutes. The Co 2+ uptake value was, in hydrated montmorillonite, between 0.3 to 0.85 m eq/g and in dehydrated montmorillonite, between 0.6 to 1.40 m eq/g. The experiments were done in a pH 5.1 to 5.7 and normal conditions. XRD patterns were used to characterize the samples. The crystallinity was determined by X-ray Diffraction and it was maintained before and after the cation exchange. DTA thermo grams showed the temperatures of the lost humidity and crystallization water. Finally, was observed that dehydrated montmorillonite adsorb more cobalt than hydrated montmorillonite. (Author)

  5. The exchangeable cations in soils flooded with sea water

    NARCIS (Netherlands)

    Molen, van der W.H.

    1958-01-01

    The changes in the exchangeable cations of soils flooded with sea-water were extensively studied in the Netherlands after the inundations of 1940, 1945 and 1953. A synopsis of the results was given, both from a theoretical and a practical viewpoint.

    Current formulae for ion-exchange tested in the

  6. Recovery of Some Radioactive Nuclides from Radioactive Waste Solution Using Silicon(IV) Antimonate as a Cation Exchanger

    International Nuclear Information System (INIS)

    Aly, H.F.; Zakaria, E.S.; El-Shorbagy, M.M.; El-Naggar, I.M.

    1999-01-01

    A new inorganic ion exchanger, silicon(IV) antimonate was prepared by dropwise addition of antimony pentachloride and sodium silicate and shows excellent thermal and chemical stability. Ion exchange selectivities of cations Na +, Cs +, Sr 2+ and Co 2+ in nitric acid media have been exchanged with protons of silicon antimonate using batch technique, from these results, distribution coefficient, selectivity was found in the order Co 2+ > Sr 2+ > Na +> Cs +. The effective separation of Cs +, Na +, Sr 2+ and Co 2+ have been achieved with column technique from nitric acid media. The values of diffusion coefficient, energy and entropy of activation of Cs +, Na +, Sr 2+ and Co 2+ on silicon antimonate matrix were determined as a particle diffusion mechanism only and the values of diffusion inside the exchanger take the order Na +> Cs +> Co 2+ > Sr 2+

  7. Thermodynamics of the extraction of scandium(III) by the liquid cation exchangers dinonylnaphthalenesulfonic acid and bis(2-ethylhexyl) phosphoric acid

    International Nuclear Information System (INIS)

    Raieh, M.A.; Zakareia, N.; Aly, H.F.

    1979-01-01

    The thermodynamic functions for the extraction of Sc 3+ by liquid cation exchangers HD and HDEHP are determined radiometrically by the temperature coefficient method. The role of the diluent dielectric constant on the extraction of Sc 3+ by HD is also studied. The thermodynamic parameters determined indicated that the free energy variation for the extraction of Sc 3+ by HD is mainly determined by the entropic terms arising from the hydration-dehydration process of the exchanged ions. In the case of HDEHP as extractant, the free energy variations are determined mainly by the entalpic terms of the system. (author)

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

    International Nuclear Information System (INIS)

    Mahendra, Ch.; Rajan, K.K.; SatyaSai, P.M.; Anand Babu, C.

    2014-01-01

    Cesium from the simulated acidic waste solution was separated using Ammonium Molybdophosphate (AMP) - Polyacrylonitrile (PAN) ion exchange resin in column operations. Electrodialysis - Ion exchange (EDIX) has been tried for the recovery of cesium from the AMP-PAN which was saturated with cesium. The electrodialysis setup consists of three compartments; cesium loaded AMP-PAN is placed in the middle compartment and is separated from the anode and cathode compartments by cation exchange membranes. Ammonium sulphate was used as anolyte and HNO 3 as catholyte. 0.1N HNO 3 was circulated in the middle compartment containing AMP-PAN to keep the resin in acidic form. On application of potential, the ammonium ions from the anode compartment migrate towards cathode through the middle compartment where they exchange with cesium ions on the resin and the exchanged cesium ions migrate towards cathode to get concentrated. Some part of cesium is recovered in the middle compartment due to convection. Cesium recovery from the AMP-PAN in the electrodialysis setup was studied at different anolyte and catholyte concentrations. All the experiments were carried out at constant current density of 40 mA/cm 2 for 15h. It was found that more than 50% of cesium recovery was observed for all the experiments studied and recovery percentage increased with increasing the anolyte concentration. It was observed that the electrolytes concentration affects the voltage drop across the cell

  9. Influence of pine bark particle size and pH on cation exchange capacity

    Science.gov (United States)

    Cation exchange capacity (CEC) describes the maximum quantity of cations a soil or substrate can hold while being exchangeable with the soil solution. While CEC has been studied for peat-based substrates, relatively little work has documented factors that affect CEC of pine bark substrates. The ob...

  10. Performance evaluation of anion exchange resins Purolite NRW-5050 and Duolite A-611 by application of radioisotopic techniques

    International Nuclear Information System (INIS)

    Singare, P.U.

    2014-01-01

    Radioanalytical techniques using 131 I and 82 Br as tracer isotopes were applied to study the kinetics of iodide and bromide ion-isotopic exchange reactions taking place between the external labeled ionic solution and the resin surface. The results indicate low values of specific reaction rate (min -1 ), amount of ion exchanged (mmol) and initial rate of ion exchange (mmol/min) for bromide ion-isotopic exchange reaction as compared to that obtained for iodide ion-isotopic exchange reaction. It was observed that for iodide ion-isotopic exchange reaction performed at 35.0 C, 1 000 g of ion exchange resins and 0.002 mol/L labeled iodide ion solution, the values of specific reaction rate (min -1 ), amount of iodide ion exchanged (mmol), initial rate of iodide ion exchange (mmol/min) and log K d were 0.340, 0.394, 0.134 and 20.2 respectively for Purolite NRW-5050 resin, which was higher than the respective values of 0.216, 0.290, 0.063 and 18.2 as that obtained by using Duolite A-611. The results of present investigation indicate that during the two ion-isotopic exchange reactions, for both the resins, there exists a strong positive linear correlation between amount of ions exchanged and concentration of ionic solution; and strong negative correlation between amount of ions exchanged and temperature of exchanging medium. From the results it appears that as compared to Duolite A-611 resins, Purolite NRW-5050 resins shows superior performance under identical experimental conditions.

  11. Template-Assisted Synthesis and Characterization of Passivated Nickel Nanoparticles

    Directory of Open Access Journals (Sweden)

    Al-Omari IA

    2010-01-01

    Full Text Available Abstract Potential applications of nickel nanoparticles demand the synthesis of self-protected nickel nanoparticles by different synthesis techniques. A novel and simple technique for the synthesis of self-protected nickel nanoparticles is realized by the inter-matrix synthesis of nickel nanoparticles by cation exchange reduction in two types of resins. Two different polymer templates namely strongly acidic cation exchange resins and weakly acidic cation exchange resins provided with cation exchange sites which can anchor metal cations by the ion exchange process are used. The nickel ions which are held at the cation exchange sites by ion fixation can be subsequently reduced to metal nanoparticles by using sodium borohydride as the reducing agent. The composites are cycled repeating the loading reduction cycle involved in the synthesis procedure. X-Ray Diffraction, Scanning Electron Microscopy, Transmission Electron microscopy, Energy Dispersive Spectrum, and Inductively Coupled Plasma Analysis are effectively utilized to investigate the different structural characteristics of the nanocomposites. The hysteresis loop parameters namely saturation magnetization and coercivity are measured using Vibrating Sample Magnetometer. The thermomagnetization study is also conducted to evaluate the Curie temperature values of the composites. The effect of cycling on the structural and magnetic characteristics of the two composites are dealt in detail. A comparison between the different characteristics of the two nanocomposites is also provided.

  12. 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)

  13. Studies on the absorption of uranium and plutonium on macroporous anion-exchange resins from mixed solvent media

    International Nuclear Information System (INIS)

    Chetty, K.V.; Mapara, P.M.; Godbole, A.G.; Swarup, Rajendra

    1995-01-01

    The ion-exchange studies on uranium and plutonium using macroporous anion-exchange resins from an aqueous-organic solvent mixed media were carried out to develop a method for their separation. Out of the several water miscible organic solvents tried, methanol and acetone were found to be best suited. Distribution data for U(VI) and Pu(IV) for three macroporous resins Tulsion A-27(MP) (strong base), Amberlyst A-26(MP) (strong base) and Amberlite XE-270(MP) (weak base) as a function of (i) nitric acid concentration (ii) organic solvent concentration were obtained. Based on the data separation factors for Pu/U were calculated. Column experiments using Tulsion A-27(MP) from a synthetic feed (HNO 3 - methanol and HNO 3 - acetone) containing Pu and U in different ratios were carried out. Plutonium was recovered from the bulk of the actual solution generated during the dissolution of plutonium bearing fuels. The method has the advantage of loading plutonium from as low as 1M nitric acid in presence of methanol or acetone and could be used satisfactorily for its recovery from solutions containing plutonium and uranium. (author). 11 refs., 4 figs., 16 tabs

  14. Cement solidification of spent ion exchange resins produced by the nuclear industry

    International Nuclear Information System (INIS)

    Jaouen, C.; Vigreux, B.

    1988-01-01

    Cement solidification technology has been applied to spent ion exchange resins for many years in countries throughout the world (at reactors, research centers and spent fuel reprocessing plants). Changing specifications for storage of radioactive waste have, however, confronted the operators of such facilities with a number of problems. Problems related both to the cement solidification process (water/cement/resin interactions and chemical interactions) and to its utilization (mixing, process control, variable feed composition, etc.) have often led waste producers to prefer other, polymer-based processes, which are very expensive and virtually incompatible with water. This paper discusses research on cement solidification of ion exchange resins since 1983 and the development of application technologies adapted to nuclear service conditions and stringent finished product quality requirements

  15. Restructuring of a peat in interaction with multivalent cations: effect of cation type and aging time.

    Directory of Open Access Journals (Sweden)

    Yamuna Kunhi Mouvenchery

    Full Text Available It is assumed to be common knowledge that multivalent cations cross-link soil organic matter (SOM molecules via cation bridges (CaB. The concept has not been explicitly demonstrated in solid SOM by targeted experiments, yet. Therefore, the requirements for and characteristics of CaB remain unidentified. In this study, a combined experimental and molecular modeling approach was adopted to investigate the interaction of cations on a peat OM from physicochemical perspective. Before treatment with salt solutions of Al(3+, Ca(2+ or Na(+, respectively, the original exchangeable cations were removed using cation exchange resin. Cation treatment was conducted at two different values of pH prior to adjusting pH to 4.1. Cation sorption is slower (>>2 h than deprotonation of functional groups (<2 h and was described by a Langmuir model. The maximum uptake increased with pH of cation addition and decreased with increasing cation valency. Sorption coefficients were similar for all cations and at both pH. This contradicts the general expectations for electrostatic interactions, suggesting that not only the interaction chemistry but also spatial distribution of functional groups in OM determines binding of cations in this peat. The reaction of contact angle, matrix rigidity due to water molecule bridges (WaMB and molecular mobility of water (NMR analysis suggested that cross-linking via CaB has low relevance in this peat. This unexpected finding is probably due to the low cation exchange capacity, resulting in low abundance of charged functionalities. Molecular modeling demonstrates that large average distances between functionalities (∼3 nm in this peat cannot be bridged by CaB-WaMB associations. However, aging strongly increased matrix rigidity, suggesting successive increase of WaMB size to connect functionalities and thus increasing degree of cross-linking by CaB-WaMB associations. Results thus demonstrated that the physicochemical structure of OM is

  16. 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.

  17. Strontium-90 in ion-exchange resin used in the Australian FIEFS network

    International Nuclear Information System (INIS)

    Wise, K.N.

    1977-10-01

    In order to determine monthly strontium-90 fallout deposited at the eight Australian monitoring stations, account must be taken of the level of strontium-90 contamination of the ion-exchange resin as prepared for use in the FIEFS. This procedure has always been important in monitoring strontium-90 fallout deposit in Australia because the level of strontium-90 contamination of ion-exchange resin, supplied by manufacturers in the Northern Hemisphere, has remained of the same order of magnitude as the monthly fallout deposit in the Southern Hemisphere

  18. Behaviour of Pu-IV with various ion exchangers in solutions containing nitric acid and oxalates

    International Nuclear Information System (INIS)

    Walter, E.; Ali, S.A.

    1982-02-01

    The distribution of Pu-IV on the ion exchangers Dowex 50W-X8, Dowex 1-X8 und Dowex Chelating Resin Al-X8 in the presence of various concentrations of nitric acid and oxalate were investigated. The results indicate that nitric acid and oxalic acid influence each other during complexation of Pu-IV with oxalate ions solutions containing nitric acid it is not possible to neglect the formation of Pu-IV nitrate complexes. The complex Pu(IV) (C 2 O 4 ) 3 2 - only is formed in solutions containing low nitric acid and high oxalic acid concentrations. The separation of Pu-IV in Dowex Chelating Resin from nitric acid solution in the presence of higher oxalate concentrations is possible, provided that the nitric acid concentration is lower than 0.25 molar [fr

  19. 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

  20. Investigation into sorption of uranium fron its high-concentrated nitric acid solutions on resin AMP

    International Nuclear Information System (INIS)

    Savel'eva, V.I.; Sudarikov, B.N.; Kireeva, G.N.; Ryzhkova, V.N.; Kandaryuk, V.V.

    1976-01-01

    Sorption of uranium has been studied on strongly basic anion-exchange resin from nitric acid solutions with concentration in metal 10-150 g/l in presence of sodium, calcium, and aluminium nitrates. Sorption of uranium from solutions has been performed by the static method with the aid of contacting the initial solution with airdry resin for 4 hours, resin to solution ratio being 1:12.5. It has been established that sorption of uranium increases with a rise in concentration of salting out agents in the following order: Al(NO 3 ) 3 > Ca(NO 3 ) 2 > Na(NO 3 ). It has been shown spectrophotometricatly that in solutions of nitrates and HNO 3 with a concentration 3 exceeds 6 mol/l

  1. Hydraulic Permeability of Resorcinol-Formaldehyde Ion-Exchange Resin - Effects of Oxygen Uptake and Radiation

    International Nuclear Information System (INIS)

    Taylor, Paul Allen

    2009-01-01

    An ion-exchange process, using spherical resorcinol-formaldehyde (RF) resin is the baseline process for removing cesium from the dissolved salt solution in the high-level waste tanks at the U.S. Department of Energy's (DOE) Hanford site in Washington State. The RF resin is also being evaluated for use in the proposed Small Column Ion Exchange (SCIX) system, which is an alternative treatment option at DOE's Savannah River Site (SRS)in South Carolina. Testing at ORNL will determine the impact of radiation exposure and oxygen uptake by the RF resin on the hydraulic permeability of the resin. Samples of the resin will be removed periodically to measure physical properties (bead size and compressibility) and cesium capacity. The proposed full-scale treatment system at Hanford, the Waste Treatment Plant (WTP), will use an ion-exchange column containing nominally 680 gal of resin, which will treat 30 gpm of waste solution. The ion-exchange column is designed for a typical pressure drop of 6 psig, with a maximum of 9.7 psig. The lab-scale column is 3-in. clear PVC pipe and is prototypic of the proposed Hanford column. The fluid velocity in the lab-scale test will be much higher than for the full-scale column, in order to generate the maximum pressure drop expected in that column (9.7 psig). The frictional drag from this high velocity will produce similar forces on the resin in the lab-scale column as would be expected at the bottom of the full-scale column. The chemical changes in the resin caused by radiation exposure and oxygen uptake are expected to cause physical changes in the resin that could reduce the bed porosity and reduce the hydraulic permeability of the resin bed. These changes will be monitored by measuring the pressure drop through the lab-scale column and by measuring the physical properties of samples of the resin. The test loop with the lab-scale column is currently being fabricated, and operation will start by late May. Testing will be completed by the

  2. Isotopic exchange between 232Th and 234Th using ion exchange resins and its application for the radiochemical separation of thorium and europium

    International Nuclear Information System (INIS)

    Sepulveda Munita, C.J.A.; Atalla, L.T.

    1980-01-01

    The determination of thorium via the measurement of 233 Th activity (obtained by irradiating natural thorium with neutrons) may suffer the interference of various radioisotopes which may be also formed during irradiation, if their parent isotopes are present in the sample. Taking into account this possibility, another technique was chosen for the determination of thorium, based on isotopic exchange associated with ionic exchange. Conditions for the isotopic exchange between 234 Th in solution and 232 Th in the resin were optimized. It was verified that the behaviour of 233 Th and 234 Th is the same regarding isotopic exchange with 232 Th. 234 Th was chosen for the experiments since it has a longer half-life (24.1 days) than 233 Th (22.3 min), thus facilitating the performance of the work. As the major objective of this work is to separate thorium and europium isotopes, the behaviour of 152-154 Eu was studied in the same system used for thorium, envisaging a minimum retention of these radioisotopes in the resin. In order to establish the best conditions for separating 234-Th and 152/154-Eu, the following parameters were considered: the thorium concentration in the solution; the hydrochloric acid concentration in solution; the concentration of other elements in solution; the degree of cross-linking of the resin; the flow rate of the solution through the column. The other elements added to the elutant solution were: uranium, molybdenum, lanthanum, europium, ytterbium, bromine, cobalt, barium, manganese, indium, cesium and selenium. Europium was added so to dilute the 152/154-Eu tracer and avoid the retention of the latter in the resin. The other elements were added because they give rise to radioisotopes which interfere in the activation analysis of thorium when 233-Th activity is used and, the separation of these elements from thorium will also be subsequently studied by the method used in the present work. (C.L.B.) [pt

  3. 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

  4. Building 579 waste ion exchange facility characterization report

    Energy Technology Data Exchange (ETDEWEB)

    Sholeen, C.M.; Geraghty, D.C.

    1997-03-01

    External direct surveys were performed for elevated {gamma} levels with a PG2 portable detector connected to a PRM 5-3 meter and for elevated {alpha} and {beta} levels with an NE portable detector. No {gamma} activity above background was detected. Several locations, the floor and west wall of building 579 and the manhole, had low levels of {beta} activity, up to 87 {+-} 49 dis/min. These values are below the allowable residual surface contamination limits for removable beta activity. There is water in the Mixed Bed Exchange Vessel, the Cation Exchange Vessel, the Closed Drain Tank, the manhole and some of the pipes. The accessible internal surfaces of the pipes, tanks and columns had higher levels of {beta} activity up to 172 {+-} 52 dis/min and some {alpha} activity up to 106 {+-} 29 dis/min. After the water is removed from the vessels, tanks, and lines, they should be surveyed to determine whether the areas accessible for smear surveys are representative of the general inside contamination levels. There are elevated levels of radionuclides in the resin from the Cation Exchange Vessel and in the water from the manhole. Since the radionuclide concentrations in the manhole water are less than ten times the site release criteria, it does not need any processing before it is released to the onsite drains. Although there are RCRA metals on the resin in the Cation Exchange Vessel, the amount that is removed during a leaching analysis is below the toxicity Characteristic level. Therefore, the resin is a radioactive waste not a mixed waste.

  5. Building 579 waste ion exchange facility characterization report

    International Nuclear Information System (INIS)

    Sholeen, C.M.; Geraghty, D.C.

    1997-03-01

    External direct surveys were performed for elevated γ levels with a PG2 portable detector connected to a PRM 5-3 meter and for elevated α and β levels with an NE portable detector. No γ activity above background was detected. Several locations, the floor and west wall of building 579 and the manhole, had low levels of β activity, up to 87 ± 49 dis/min. These values are below the allowable residual surface contamination limits for removable beta activity. There is water in the Mixed Bed Exchange Vessel, the Cation Exchange Vessel, the Closed Drain Tank, the manhole and some of the pipes. The accessible internal surfaces of the pipes, tanks and columns had higher levels of β activity up to 172 ± 52 dis/min and some α activity up to 106 ± 29 dis/min. After the water is removed from the vessels, tanks, and lines, they should be surveyed to determine whether the areas accessible for smear surveys are representative of the general inside contamination levels. There are elevated levels of radionuclides in the resin from the Cation Exchange Vessel and in the water from the manhole. Since the radionuclide concentrations in the manhole water are less than ten times the site release criteria, it does not need any processing before it is released to the onsite drains. Although there are RCRA metals on the resin in the Cation Exchange Vessel, the amount that is removed during a leaching analysis is below the toxicity Characteristic level. Therefore, the resin is a radioactive waste not a mixed waste

  6. Selective separation of indium by iminodiacetic acid chelating resin

    International Nuclear Information System (INIS)

    Fortes, M.C.B.; Benedetto, J.S.; Martins, A.H.

    2007-01-01

    - Indium can be recovered by treating residues, flue dusts, slags, and metallic intermediates in zinc smelting. This paper investigates the adsorption characteristics of indium and iron on an iminodiacetic acid chelating resin, Amberlite R IRC748 (Rohm and Haas Co.-USA). High concentrations of iron are always present in the aqueous feed solution of indium recovery. In addition, the chemical behaviour of iron in adsorptive systems is similar to that of indium. The metal concentrations in the aqueous solution were based on typical indium sulfate leach liquor obtained from zinc hydrometallurgical processing in a Brazilian plant. The ionic adsorption experiments were carried out by the continuous column method. Amberlite R IRC748 resin had a high affinity for indium under acidic conditions. Indium ions adsorbed onto the polymeric resin were eluted with a 0.5 mol/dm 3 sulphuric acid solution passed through the resin bed in the column. 99.5% pure indium sulfate aqueous solution was obtained using the iminodiacetic acid chelating resin Amberlite R IRC748. (author)

  7. Literature study of volatile radioiodine release from ion-exchange resins during transportation

    International Nuclear Information System (INIS)

    Wren, J.C.

    1991-02-01

    A transport package is currently being developed by Ontario Hydro to carry used filters and ion-exchange columns from the Pickering and Darlington Nuclear Generating Stations to the Bruce Nuclear Generating Station for disposal. The main reason that the transport package must be licensed is the possibility that volatile radionuclides being transported in the package might be released during transport accidents. Of particular concern is the iodine that might become volatile due to the degradation of the ion exchange resin. This report reviews the literature on the thermal and radiolytic degradation of ion exchange resins and provides calculations to estimate the fraction of volatile iodine as a function of time under postulated accident conditions

  8. Mechanism of protodesorption—exchange of heavy metal cations for protons in a heterophase system of H{sub 2}O–H{sub 2}SO{sub 4}–MSO{sub 4}—cellulose sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Kozlov, V.A.; Nikiforova, T.E., E-mail: tatianaenik@mail.ru; Loginova, V.A.; Koifman, O.I.

    2015-12-15

    Highlights: • Protodesorption takes place with participation of anions. • The interphase indicator MSO{sub 4} is used in ion exchange investigation. • In ion exchange process salt and acid participate in equivalent proportions. • In a protodesorption process proton acts in degree of ½. • M{sup 2+}/2Na{sup +} and M{sup 2+}/2H{sup +} exchanges take place in ion and molecular forms. - Abstract: The influence of pH on the distribution of metal cations [Cd(II), Cu(II), Fe(II), Ni(II), Zn(II)] in a four-component heterophase system (H{sub 2}O–H{sub 2}SO{sub 4}–MSO{sub 4}–cellulose sorbent) was studied. Protodesorption of metal cations was studied with indicator and constant quantities of [MSO{sub 4}] salts and constant solvent–sorbent ratio. Linear dependence lgK{sub DM2+} = f(pH) with tgα = 1/2 of the K{sub DM2+} metal ions distribution coefficients from the acidity of the aqueous phase is observed in logarithmic coordinates. Depression of the exponent corresponding to proton involvement in protodesorption from 2 (theory) to 0.5 (experiment) indicates that anions of the aqueous phase are involved in the process of exchange of metal cation for proton on the anionic centers of the sorbent, which corresponds to participation of the salt and acid components of the system in molecular non-dissociated form in an equivalent proportion H{sub 2}SO{sub 4}/MSO{sub 4} = 1/1. Different behavior of the salt and acid components in ion exchange of cations for cations and cations for protons is due to the differences in the constraint coefficients of their molecular and ionic forms which must be taken into consideration in equations describing thermodynamics of the interphase exchange.

  9. The immobilization of anion exchange resins in polymer modified cements

    International Nuclear Information System (INIS)

    Dyer, A.; Morgan, P.D.

    1991-09-01

    Organic anion exchange resins, loaded with 99-Tc as the pertechnate ion, were incorporated into polymer modified cements (Flexocrete Ltd, Preston). BFS/OPC (9:1 mix) also was modified by three polymers from the same source (styrene acrylic (2) styrene butadiene) and loaded with anion exchanger containing the pertechnate. Composites were tested for initial compressive strengths, under water and radiation stability and leach rate. IAEA standard leach testing was with simulated sea and ground waters. Ground water leaching also was carried out on composites subjected to 1.10 9 rads (γ). Leach testing correlated well with compressive strength. Modified composites performed better than the BFS/OPC mix under all conditions studied and were able to encapsulate higher resin loadings. (author)

  10. Improvement of incineration efficiency of spent ion exchange resins on the incinerator at nuclear power plants. Manufacturing the solids of the resins mixed with paraffin wax and their incinerating test results on actual incinerator

    International Nuclear Information System (INIS)

    Izumi, Takeshi; Ohtsu, Takashi; Inagawa, Hirofumi; Kawakami, Takashi; Hagiwara, Masahiro; Ino, Takao; Ishiyama, Yuji

    2011-01-01

    In nuclear power plants, ion exchange resins are used at water purification systems such as condensate demineralizers. After usage, used ion exchange resins are stored at plants as low level radioactive wastes. Ion exchange resins contain water and so, those are flame resistant materials. At present, ion exchange resins are incinerated with other inflammable materials at incinerators. Furthermore, ion exchange resins are fine particle beads and are easy to be scattered in all directions, so operators must pay attentions for treatment. Then, we have developed the new solidification system of ion exchange resins with paraffin wax. Ion exchange resins are mixed and extruded with paraffin wax and these solids are enabled to incinerate at existing incinerators. In order to demonstrate this new method, we made the large amount of solids and incinerated them at actual incinerator. From these results, we have estimated to be able to incinerate the solids only at actual incinerator. (author)

  11. Use of new tandem cation/anion exchange system with clinical-scale generators provides high specific volume solutions of technetium-99m and rhenium-188

    International Nuclear Information System (INIS)

    Knapp, F.F. Jr.; Beets, A.L.; Mirzadeh, S.; Guhlke, S.

    1998-01-01

    In this paper we describe the first application of our simple and inexpensive post-elution tandem cation/anion exchange column system which is based on generator elution with salts of weak acids such as ammonium acetate instead of saline solution to provide very high specific volume solutions of technetium-99m and rhenium-188 from clinical-scale molybdenum-99/technetium-99m generator prepared from low specific activity (n,y) molybdenum-99, and tungsten-188/rhenium-188 generators, respectively. Initial passage of the bolus through a strong cation exchange cartridge converts the ammonium acetate to acetic acid which is essentially not ionized at the acidic pH, allowing specific subsequent amine-type (QMA SepPak TM ) anion exchange cartridge column trapping of the microscopic levels of the pertechnetate or perrhenate. Subsequent elution of the anion cartridge with a small volume ( 500 mCi/mL) from the alumina-based tungsten-188/rhenium-188 generator. (author)

  12. 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

  13. 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)

  14. Nongeminate radiative recombination of free charges in cation-exchanged PbS quantum dot films

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Ashley R. [National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401 (United States); Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309 (United States); Beard, Matthew C.; Johnson, Justin C. [National Renewable Energy Laboratory, 15013 Denver West Pkwy., Golden, CO 80401 (United States)

    2016-06-01

    Highlights: • Photoluminescence and transient absorption are used to probe PbS QD films. • Cation-exchanged PbS QDs show room-temperature PL emission. • Bimolecular recombination is shown for the first time in coupled, PbS QD films. - Abstract: Using photoluminescence (PL) spectroscopy we explore the radiative recombination pathways in PbS quantum dots (QDs) synthesized by two methods. We compare conventionally synthesized PbS from a PbO precursor to PbS synthesized using cation-exchange from CdS QDs. We show that strongly coupled films of PbS QDs from the cation-exchange luminesce with significant efficiency at room temperature. This is in stark contrast to conventional PbS QDs, which have exceedingly weak room temperature emission. Moreover, the power dependence of the emission is quadratic, indicating bimolecular radiative recombination that is reasonably competitive with trap-assisted recombination, a feature previously unreported in coupled PbS QD films. We interpret these results in terms of a greatly reduced defect concentration for cation-exchanged QDs that mitigates the influence of trap-assisted recombination. Cation-exchanged QDs have recently been employed in highly efficient and air-stable lead chalcogenide QD devices, and the reduced number of trap states inferred here may lead to improved current collection and higher open circuit voltage.

  15. Kinetic investigation of the immobilization of chromotropic acid derivatives onto anion exchange resin

    Directory of Open Access Journals (Sweden)

    Savić Jasmina

    2007-01-01

    Full Text Available The adsorption kinetics of pyrazol- (РАСА and imidazol-azo-chromo-tropic acid (IACA onto Dowex 1-X8 resin, as a function of the dye concentration and temperature were investigated at pH 4.5. The pseudo-first- and second-order kinetic models and intraparticle diffusion model were used to describe the obtained kinetic data. The adsorption rate constants were found to be in the order of magnitude 10-2 min-1 for all of the used kinetics models. The adsorption capacity increases with increasing initial dye concentration. The study of adsorption kinetics at different temperatures (in the range from 5 to 25 °C reveals an increase in the rate of adsorption and adsorption capacity with increasing temperature. The activation energy (in the case of РАСА 16.6 kJ/mol, and for IACA 11.3 kJ/mol was determined using the Arrhenius dependence. Electrostatic interactions between the dye and resin beads were shown to be the adsorption mechanism.

  16. New Anion-Exchange Resins for Improved Separations of Nuclear Materials

    International Nuclear Information System (INIS)

    Bartsch, Richard A.; Barr, Mary E.

    2001-01-01

    Improved separations of nuclear materials will have a significant impact upon a broad range of DOE activities. DOE-EM Focus Areas and Crosscutting Programs have identified improved methods for the extraction and recovery of radioactive metal ions from process, waste, and environmental waters as critical needs for the coming years. We propose to develop multifunctional anion-exchange resins that facilitate anion uptake by carefully controlling the structure of the anion receptor site. Our new ion-exchange resins interface the field of ion-specific chelating ligands with robust, commercial ion-exchange technology to provide materials which exhibit superior selectivity and kinetics of sorption and desorption. The following Focus Areas and Crosscutting Programs have described needs that would be favorably impacted by the new material: Efficient Separations and Processing - radionuclide removal from aqueous phases; Plutonium - Pu, Am or total alpha removal to meet regulatory requirement s before discharge to the environment; Plumes - U and Tc in groundwater, U, Pu, Am, and Tc in soils; Mixed Waste - radionuclide partitioning; High-Level Tank Waste - actinide and Tc removal from supernatants and/or sludges. The basic scientific issues which need to be addressed are actinide complex speciation along with modeling of metal complex/functional site interactions in order to determine optimal binding-site characteristics. Synthesis of multifunctionalized extractants and ion-exchange materials that implement key features of the optimized binding site, and testing of these materials, will provide feedback to the modeling and design activities. Resin materials which actively facilitate the uptake of actinide complexes from solution should display both improved selectivity and kinetic properties. The long-range implications of this research, however, go far beyond the nuclear complex. This new methodology of ''facilitated uptake'' could revolutionize ion-exchange technology

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

    International Nuclear Information System (INIS)

    Penwell, D.L.

    1994-01-01

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

  18. Separation and concentration of lead, uranium and copper using polystyrene resins functionalised with azobenzylphosphonic acid ligands

    International Nuclear Information System (INIS)

    Ueda, Kazumasa; Sato, Yuko; Yoshimura, Osamu; Yamamoto, Yoshikazu

    1988-01-01

    Two polystyrene resins functionalised with azobenzylphosphonic acid ligands were synthesised and applications for the concentration, separation and determination of micro- or milligram concentrations of metal ions were studied. Physical and chemical properties such as specific mass, water content and ion-exchange capacity were measured and the characteristics of the resins were examined. The resins were especially useful for the concentration of Pbsup(II), Usup(VI) and Cusup(II) by batch and column operations, and effective separations of Pbsup(II) from Group VIII and IIB ions could be achieved by selecting the eluents. Trace amounts of Pbsup(II), Usup(VI), Cusup(II), Mnsup(II), Znsup(II) and Fesup(III) were quantitatively retained on the resin columns at neutral pH and easily recovered by elution with 2M HCl and 2M HNO 3 . The resins were successfully applied to the concentration of trace amounts of metals in river and sea waters prior to spectroscopic determinations. (author)

  19. Enhanced vanillin production from ferulic acid using adsorbent resin.

    Science.gov (United States)

    Hua, Dongliang; Ma, Cuiqing; Song, Lifu; Lin, Shan; Zhang, Zhaobin; Deng, Zixin; Xu, Ping

    2007-03-01

    High vanillin productivity was achieved in the batch biotransformation of ferulic acid by Streptomyces sp. strain V-1. Due to the toxicity of vanillin and the product inhibition, fed-batch biotransformation with high concentration of ferulic acid was unsuccessful. To solve this problem and improve the vanillin yield, a biotransformation strategy using adsorbent resin was investigated. Several macroporous adsorbent resins were chosen to adsorb vanillin in situ during the bioconversion. Resin DM11 was found to be the best, which adsorbed the most vanillin and the least ferulic acid. When 8% resin DM11 (wet w/v) was added to the biotransformation system, 45 g l(-1) ferulic acid could be added continually and 19.2 g l(-1) vanillin was obtained within 55 h, which was the highest vanillin yield by bioconversion until now. This yield was remarkable for exceeding the crystallization concentration of vanillin and therefore had far-reaching consequence in its downstream processing.

  20. Cation exchange process for molten salt extraction residues

    International Nuclear Information System (INIS)

    Proctor, S.G.

    1975-01-01

    A new method, utilizing a cation exchange technique, has been developed for processing molten salt extraction (MSE) chloride salt residues. The developed ion exchange procedure has been used to separate americium and plutonium from gross quantities of magnesium, potassium, and sodium chloride that are present in the residues. The recovered plutonium and americium contained only 20 percent of the original amounts of magnesium, potassium, and sodium and were completely free of any detectable amounts of chloride impurity. (U.S.)

  1. Water contentwater of determination of cationic polystyrene sulfonate resins by infrared spectrophotometry

    International Nuclear Information System (INIS)

    Noki, V.

    1987-01-01

    A method of the determination of water content in polystyrene sulfonate ion-exchange resins in the presence of alkaline earth counter-ions by I.R. spectrophotometry is proposed. This method does not hold in the case of transition metal due to the formation of coordinated complexes with water molecules.

  2. Incineration of spent ion exchange resins in a triphasic mixture at Belgoprocess

    International Nuclear Information System (INIS)

    Deckers, J.; Luycx, P.

    2003-01-01

    Up to 1998, spent ion exchange resins have been fed to the incinerator in combination with various other solid combustible wastes at Belgoprocess. However, thanks to sustained efforts to reduce radioactive waste production in all nuclear facilities in Belgium, the annual production of solid combustible waste is now much too small to allow this practice to be continued. Since the incinerator at Belgoprocess is not capable of treating spent ion exchange resins as such, it was decided to adopt the use of foam as a carrier to feed the resins to the incinerator. The mixture is a pseudohomogeneous charged foam, ensuring easy handling and allowing incineration in the existing furance, while a number of additives may be included, such as oil to increase the calorific value of the mixture and accelerate combustion. The first incineration campaign of spent ion exchange resins in a triphasic foam mixture, in conjunction with other liquid and solid combustible wastes, will be started in January 2000. The foam, comprising 70% by weight of resins, 29% by weight of water and 1% by weight of surfactant will be pulverized in the incinerator through an injection lance, at a feed rate of 40 to 100 kg/h. The incinerator and associated off-gas treatment system can be operated at standard conditions. Belgoprocess is the subsidiary of the Belgian national agency for the management of radioactive waste, known by its Dutch and French acronyms, NIRAS and ONDRAF respectively. The company ensures the treatment, conditioning and interim storage of nearly all radioactive waste produced in Belgium. (orig.)

  3. Alternative extraction of alkaloid anticarcinogens from Brazilian "vinca rosea" using Ion exchange chromatography

    Directory of Open Access Journals (Sweden)

    Sérgio Freire de Carvalhaes

    Full Text Available Extracts in ethanol and ethanol-ammonia of dried leaves from Catharanthus roseus, gathered at Rio de Janeiro state, were adsorbed in a strongly acidic cation exchange resin with sulfonic acid group, using the finite bath method, resulting in an alkaloid retained fraction and an acidic and neutral unretained fraction. High Performance Liquid Chromatography showed the isolation of the alkaloid fraction to be highly selective and with good performance, with an absence of alkaloids in the unretained fraction, while the retained fraction presented 1,54-6,35 mg/g of vindoline and 0,12-0,91 mg/g of vinblastine, common for an alkaloid-rich concentrate, usually obtained by classic extraction with several steps using solvents.

  4. Exchanged cations and water during reactions in polypyrrole macroions from artificial muscles.

    Science.gov (United States)

    Valero, Laura; Otero, Toribio F; Martínez, José G

    2014-02-03

    The movement of the bilayer (polypyrrole-dodecylbenzenesulfonate/tape) during artificial muscle bending under flow of current square waves was studied in aqueous solutions of chloride salts. During current flow, polypyrrole redox reactions result in variations in the volumes of the films and macroscopic bending: swelling by reduction with expulsion of cations and shrinking by oxidation with the insertion of cations. The described angles follow a linear function, different in each of the studied salts, of the consumed charge: they are faradaic polymeric muscles. The linearity indicates that cations are the only exchanged ions in the studied potential range. By flow of the same specific charge in every electrolyte, different angles were described by the muscle. The charge and the angle allow the number and volume of both the exchanged cations and the water molecules (related to a reference) between the film to be determined, in addition to the electrolyte per unit of charge during the driving reaction. The attained apparent solvation numbers for the exchanged cations were: 0.8, 0.7, 0.6, 0.5, 0.5, 0.4, 0.25, and 0.0 for Na(+), Mg(2+), La(3+), Li(+), Ca(2+), K(+), Rb(+), and Cs(+), respectively. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Uranium(VI) adsorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety

    International Nuclear Information System (INIS)

    Matsuda, Masaaki; Akiyoshi, Yoshirou

    1991-01-01

    Uranium(VI) adsorption and desorption properties of a chelating resin containing polyamine-substituted methylphosphonic acid moiety of 2.29 mmol/g-resin (APA) were examined. Uranium(VI) adsorption properties of several ion exchange resins and extractant agents which were known as excellent adsorbents for uranium(VI), were examined together for a comparison with those of APA. Uranium(VI) adsorption capacity of APA at the concentration of 100 mg·dm -3 -uranium(VI) in 100 g·dm -3 -H 2 SO 4 aq. soln., 190 g·dm -3 -H 3 PO 4 aq. soln. and uranium enriched sea water, was 0.2, 0.05 and 0.05 mmol·g -1 respectively. The adsorption capacity of APA for uranium(VI) in these solutions was larger than that of another adsorbents, except the adsorption of uranium(VI) in enriched sea water on ion exchange resin containing phosphoric acid moiety (adsorption capacity ; 0.2 mmol·g -1 ). Uranium(VI) adsorption rate on APA was high and the relation between treatment time (t : min) and uranium(VI) concentration (y : mg·dm -3 ) in 100 g·dm -3 H 2 SO 4 aq. soln. after treatment, was shown as following equation, y=20 0.048t+1.90 (0≤t≤30). The adsorbed uranium(VI) on APA was able to be eluted with a mixed aq. soln. of hydrogen peroxide and sodium hydroxide and also was able to be eluted with an aq. alkaline soln. dissolved reduction agents such as sodium sulfite and hydrazine. From these results, it was thought that uranium(VI) adsorbed on APA was eluted due to the reduction to uranium(VI) by these eluents. (author)

  6. Review on cation exchange selectivity coefficients for MX-80 bentonite

    International Nuclear Information System (INIS)

    Domenech, C.; Arcos, D.; Duro, L.; Sellin, P.

    2005-01-01

    Full text of publication follows: Bentonite is considered as engineered barrier in the near field of a nuclear waste repository due to its low permeability, what impedes groundwater flow to the nuclear waste, and its high retention capacity (sorption) of radionuclides in the eventuality of groundwater intrusion. One of the main retention processes occurring at the bentonite surface is ion exchange. This process may exert a strong control on the mobility of major pore water cations. Changes in major cation concentration, especially calcium, can affect the dissolution-precipitation of calcite, which in turn controls one of the key parameters in the system: pH. The cation exchange process is usually described according to the Gaines-Thomas convention: Ca 2+ + 2 NaX = CaX 2 + 2 Na + , K Ca = (N Ca x a 2 Na + )/(N 2 Na x a Ca 2+ ) where K Ca is the selectivity coefficient for the Ca by Na exchange, ai is the activity of cation 'i' in solution and NJ the equivalent fractional occupancy of cation 'J' in bentonite. Parameters such as solid to liquid (S:L) ratio and dry density of the solid have an important influence on the value of selectivity coefficients (K ex ). Although in most geochemical modelling works, K ex values are directly taken from experiments conducted at low S:L ratios and low dry densities, the expected conditions in a deep geological nuclear waste repository are higher S:L and higher bentonite density (1.6 g.cm -3 in the SKB design to obtain a fully water saturated density of around 2.0 g.cm -3 ). Experiments focused at obtaining selectivity coefficients under the conditions of interest face the difficulty of achieving a proper extraction and analyses of pore water without disturbing the system by the sampling method itself. In this work we have conducted a complete analyses of published data on MX-80 bentonite cationic exchange in order to assess the effect of the S:L ratio and dry density on the value of the selectivity coefficients determined so far

  7. Relating saturation capacity to charge density in strong cation exchangers.

    Science.gov (United States)

    Steinebach, Fabian; Coquebert de Neuville, Bertrand; Morbidelli, Massimo

    2017-07-21

    In this work the relation between physical and chemical resin characteristics and the total amount of adsorbed protein (saturation capacity) for ion-exchange resins is discussed. Eleven different packing materials with a sulfo-functionalization and one multimodal resin were analyzed in terms of their porosity, pore size distribution, ligand density and binding capacity. By specifying the ligand density and binding capacity by the total and accessible surface area, two different groups of resins were identified: Below a ligand density of approx. 2.5μmol/m 2 area the ligand density controls the saturation capacity, while above this limit the accessible surface area becomes the limiting factor. This results in a maximum protein uptake of around 2.5mg/m 2 of accessible surface area. The obtained results allow estimating the saturation capacity from independent resin characteristics like the saturation capacity mainly depends on "library data" such as the accessible and total surface area and the charge density. Hence these results give an insight into the fundamentals of protein adsorption and help to find suitable resins, thus limiting the experimental effort in early process development stages. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. In vivo cation exchange in quantum dots for tumor-specific imaging.

    Science.gov (United States)

    Liu, Xiangyou; Braun, Gary B; Qin, Mingde; Ruoslahti, Erkki; Sugahara, Kazuki N

    2017-08-24

    In vivo tumor imaging with nanoprobes suffers from poor tumor specificity. Here, we introduce a nanosystem, which allows selective background quenching to gain exceptionally tumor-specific signals. The system uses near-infrared quantum dots and a membrane-impermeable etchant, which serves as a cation donor. The etchant rapidly quenches the quantum dots through cation exchange (ionic etching), and facilitates renal clearance of metal ions released from the quantum dots. The quantum dots are intravenously delivered into orthotopic breast and pancreas tumors in mice by using the tumor-penetrating iRGD peptide. Subsequent etching quenches excess quantum dots, leaving a highly tumor-specific signal provided by the intact quantum dots remaining in the extravascular tumor cells and fibroblasts. No toxicity is noted. The system also facilitates the detection of peritoneal tumors with high specificity upon intraperitoneal tumor targeting and selective etching of excess untargeted quantum dots. In vivo cation exchange may be a promising strategy to enhance specificity of tumor imaging.The imaging of tumors in vivo using nanoprobes has been challenging due to the lack of sufficient tumor specificity. Here, the authors develop a tumor-specific quantum dot system that permits in vivo cation exchange to achieve selective background quenching and high tumor-specific imaging.

  9. Use of a new tandem cation/anion exchange system with clinical-scale generators provides high specific volume solutions of technetium-99m and rhenium-188

    International Nuclear Information System (INIS)

    Knapp, F.R. Jr.; Beets, A.L.; Mirzadeh, S.; Guhlke, S.; Univ. of Bonn

    1998-03-01

    In this paper the authors describe the first application of a simple and inexpensive post elution tandem cation-anion exchange column system which is based on generator elution with salts of weak acids such as ammonium acetate instead of saline solution to provide very high specific volume solutions of technetium-99m and rhenium-188 from clinical scale molybdenum-99/technetium-99m generator prepared from low specific activity (n,y) molybdenum-99, and tungsten-188/rhenium-188 generators, respectively. Initial passage of the bolus through a strong cation exchange cartridge converts the ammonium acetate to acetic acid which is essentially not ionized at the acidic pH, allowing specific subsequent amine type (QMA SepPak trademark) anion exchange cartridge column trapping of the microscopic levels of the pertechnetate or perrhenate. Subsequent elution of the anion cartridge with a small volume ( 500 mCi/mL) from the alumina-based tungsten-188/rhenium-188 generator

  10. Kinetics of soybean oil epoxidation with peracetic acid formed in situ in the presence of an ion exchange resin: Pseudo-homogeneous model

    Directory of Open Access Journals (Sweden)

    Janković Milovan

    2017-01-01

    Full Text Available A kinetic model was proposed for the epoxidation of vegetable oils with peracetic acid formed in situ from acetic acid and hydrogen peroxide in the presence of an acidic ion exchange resin as a catalyst. The model is pseudo-homogeneous with respect to the catalyst. Besides the main reactions of peracetic acid and epoxy ring formation, the model takes into account the side reaction of epoxy ring opening with acetic acid. The partitioning of acetic acid and peracetic acid between the aqueous and organic phases and the change in the phases’ volumes during the process were considered. The temperature dependency of the apparent reaction rate coefficients is described by a reparameterized Arrhenius equation. The constants in the proposed model were estimated by fitting the experimental data obtained for the epoxidations of soybean oil conducted under defined reaction conditions. The highest epoxy yield of 87.73% was obtained at 338 K when the mole ratio of oil unsaturation:acetic acid:hydrogen peroxide was 1:0.5:1.35 and when the amount of the catalyst Amberlite IR-120H was 4.04 wt.% of oil. Compared to the other reported pseudo-homogeneous models, the model proposed in this study better correlates the change of double bond and epoxy group contents during the epoxidation process. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III45022

  11. An evaluation of organic substance fraction removal during ion exchange with Miex-DOC resin.

    Science.gov (United States)

    Wolska, Małgorzata

    2015-07-01

    In this study, the usefulness of Miex-DOC resin in eliminating organic substances and their fractions from water sources for drinking water was evaluated. The objects of study were samples from three surface water sources and one infiltration water source taken at water treatment plants before treatment in technical conditions. In particular, the effectiveness of removing biodegradable and non-biodegradable fractions as a function of resin dosages and water-resin contact times was evaluated. The ion exchange process with the Miex-DOC resin achieved a high effectiveness in removing aromatic non-biodegradable organic substances, and therefore a reduction in UV254 absorbance. The biodegradable fraction is much less susceptible to removal yet its removal effectiveness allows for a significant reduction in hazards connected with secondary microorganism development. The results of this study indicate the possibility of using ion exchange with the Miex-DOC resin for effective removal of disinfection by-product precursors.

  12. Exchangeable cations-mediated photodegradation of polycyclic aromatic hydrocarbons (PAHs) on smectite surface under visible light

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Hanzhong, E-mail: jiahz@ms.xjb.ac.cn [Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011 (China); Li, Li [Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011 (China); Chen, Hongxia; Zhao, Yue [Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011 (China); School of Geology and Mining Engineering, Xinjiang University, Urumqi 830046 (China); Li, Xiyou [Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011 (China); Wang, Chuanyi, E-mail: cywang@ms.xjb.ac.cn [Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011 (China)

    2015-04-28

    Graphical abstract: Roles of exchangeable cations in PAHs photodegradation on clay surafces under visible light. - Highlights: • Photolysis rate are strongly dependent on the type of cations on clay surface. • The strength of “cation–π” interactions governs the photodegradation rate of PAHs. • Several exchangeable cations could cause a shift in the absorption spectrum of PAHs. • Exchangeable cations influence the type and amount of reactive intermediates. - Abstract: Clay minerals saturated with different exchangeable cations are expected to play various roles in photodegradation of polycyclic aromatic hydrocarbons (PAHs) via direct and/or indirect pathways on clay surfaces. In the present study, anthracene and phenanthrene were selected as molecule probes to investigate the roles of exchangeable cations on their photodegradation under visible light irradiation. For five types of cation-modified smectite clays, the photodegradation rate of anthracene and phenanthrene follows the order: Fe{sup 3+} > Al{sup 3+} > Cu{sup 2+} >> Ca{sup 2+} > K{sup +} > Na{sup +}, which is consistent with the binding energy of cation–π interactions between PAHs and exchangeable cations. The result suggests that PAHs photolysis rate depends on cation–π interactions on clay surfaces. Meanwhile, the deposition of anthracene at the Na{sup +}-smectite and K{sup +}-smectite surface favors solar light absorption, resulting in enhanced direct photodecomposition of PAHs. On the other hand, smectite clays saturated with Fe{sup 3+}, Al{sup 3+}, and Cu{sup 2+} are highly photoreactive and can act as potential catalysts giving rise to oxidative radicals such as O{sub 2}{sup −}· , which initiate the transformation of PAHs. The present work provides valuable insights into understanding the transformation and fate of PAHs in the natural soil environment and sheds light on the development of technologies for contaminated land remediation.

  13. Exchangeable cations-mediated photodegradation of polycyclic aromatic hydrocarbons (PAHs) on smectite surface under visible light

    International Nuclear Information System (INIS)

    Jia, Hanzhong; Li, Li; Chen, Hongxia; Zhao, Yue; Li, Xiyou; Wang, Chuanyi

    2015-01-01

    Graphical abstract: Roles of exchangeable cations in PAHs photodegradation on clay surafces under visible light. - Highlights: • Photolysis rate are strongly dependent on the type of cations on clay surface. • The strength of “cation–π” interactions governs the photodegradation rate of PAHs. • Several exchangeable cations could cause a shift in the absorption spectrum of PAHs. • Exchangeable cations influence the type and amount of reactive intermediates. - Abstract: Clay minerals saturated with different exchangeable cations are expected to play various roles in photodegradation of polycyclic aromatic hydrocarbons (PAHs) via direct and/or indirect pathways on clay surfaces. In the present study, anthracene and phenanthrene were selected as molecule probes to investigate the roles of exchangeable cations on their photodegradation under visible light irradiation. For five types of cation-modified smectite clays, the photodegradation rate of anthracene and phenanthrene follows the order: Fe 3+ > Al 3+ > Cu 2+ >> Ca 2+ > K + > Na + , which is consistent with the binding energy of cation–π interactions between PAHs and exchangeable cations. The result suggests that PAHs photolysis rate depends on cation–π interactions on clay surfaces. Meanwhile, the deposition of anthracene at the Na + -smectite and K + -smectite surface favors solar light absorption, resulting in enhanced direct photodecomposition of PAHs. On the other hand, smectite clays saturated with Fe 3+ , Al 3+ , and Cu 2+ are highly photoreactive and can act as potential catalysts giving rise to oxidative radicals such as O 2 − · , which initiate the transformation of PAHs. The present work provides valuable insights into understanding the transformation and fate of PAHs in the natural soil environment and sheds light on the development of technologies for contaminated land remediation

  14. Perchlorate adsorption and desorption on activated carbon and anion exchange resin.

    Science.gov (United States)

    Yoon, In-Ho; Meng, Xiaoguang; Wang, Chao; Kim, Kyoung-Woong; Bang, Sunbaek; Choe, Eunyoung; Lippincott, Lee

    2009-05-15

    The mechanisms of perchlorate adsorption on activated carbon (AC) and anion exchange resin (SR-7 resin) were investigated using Raman, FTIR, and zeta potential analyses. Batch adsorption and desorption results demonstrated that the adsorption of perchlorate by AC and SR-7 resin was reversible. The reversibility of perchlorate adsorption by the resin was also proved by column regeneration test. Solution pH significantly affected perchlorate adsorption and the zeta potential of AC, while it did not influence perchlorate adsorption and the zeta potential of resin. Zeta potential measurements showed that perchlorate was adsorbed on the negatively charged AC surface. Raman spectra indicated the adsorption resulted in an obvious position shift of the perchlorate peak, suggesting that perchlorate was associated with functional groups on AC at neutral pH through interactions stronger than electrostatic interaction. The adsorbed perchlorate on the resin exhibited a Raman peak at similar position as the aqueous perchlorate, indicating that perchlorate was adsorbed on the resin through electrostatic attraction between the anion and positively charged surface sites.

  15. New technique for synthesizing AMP : precipitation inside an ion-exchange resin and its application to separation of cesium from fission-products and to A137sub(m) Ba generator

    International Nuclear Information System (INIS)

    Matsuda, H.T.; Abrao, A.

    1980-06-01

    A new technique for synthesizing ammonium molybdophosphate, an inorganic ion exchanger which retains selectively cesium-137 from a mixture of fission products, is dealt with. Normally the use of this exchanger in column operation requires the use of asbestos, silica-gel or organic polymers as binder, due to its microcrystalline form. The new process employs a strong anionic resin, saturated with molybdate anions. This method enables the precipitation of ammonium molybdophosphate directly into the resinous structure by adding dihydrogen ammonium phosphate in 7,5M HNO 3 . The reactants maintened at 60 0 C for a period of four hours has been found to be the optimum condition for a maximum yield of this compound (anionic resin-ammonium molybdophosphate=R-AMP). The tests performed for characterizing this compound are: molybdenum-phosphorus ratio determination, electronic absorption spectra, infra-red absorption spectra, reflection microscopy observations, electron probe micro-analysis and X-ray powder patterns. The mentioned analysis confirmed the presence of the ammonium molybdophosphate in the resinous structure, permitting, thereby, its use as a cation exchanger. R-AMP showed a capacity of 0,48mE/g of dry material. The cesium retention studies were made using columns charged with R-AMP compound. The behavior of some polivalent fission products was also studied. The R-AMP columns was finally applied to separate cesium from irradiated uranium solutions. A method for the isolation of sup(137m)Ba by successive elutions from R-AMP ( 137 Cs) exchanger (generator) is described. (Author) [pt

  16. Study on the removal of iron impurities in methanesulfonic acid tin plating bath

    Science.gov (United States)

    Hou-li, LIU; Jian-Jun, CHEN; Hong-Liang, PAN

    2018-03-01

    This thesis investigated the the influence of sodium sulfite as reducing agent on the recovery rate of tin ion. The approach is that HZ016 type cation exchange resin was used to adsorb Sn2+ and Fe2+ in electroplated tin solution first. After adsorption, the resin was removed by sulfuric acid, which was added with NaOH to adjust pH value to form precipitation and separate tin. X-ray diffraction (XRD) and energy spectrum (EDS) method were used to analyze the composition of the precipitates adjusted by pH. The results show that when the mass ratio of resin to bath is 1:2, the adsorption efficiency of resin reaches 98.3% and 97.1% respectively, and the elution efficiency of tin and iron reaches 95.1% and 94% respectively when the mass ratio of resin to eluent sulfuric acid is 1:4. Sodium sulfite was added to increase the efficiency of tin recovery by 8.1%. EDS and XRD atlas showed that after pH regulation, the main composition of the filtration precipitation was the hydroxides of tin.

  17. 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)

  18. Dissolution of ion exchange resin by hydrogen peroxide

    International Nuclear Information System (INIS)

    Lee, S.C.

    1981-08-01

    The resin dissolution process was conducted successfully in full-scale equipment at the SRL Semiworks. A solution containing 0.001M Fe 2+ , or Fe 3+ , and 3 vol % H 2 O 2 in 0.1M HNO 3 is sufficient to dissolve up to 40 vol % resin slurry (Dowex 50W-X8). Foaming and pressurization can be eliminated by maintaining the dissolution temperature below 99 0 C. The recommended dissolution temperature range is 85 to 90 0 C. Premixing hydrogen peroxide with all reactants will not create a safety hazard, but operating with a continual feed of hydrogen peroxide is recommended to control the dissolution rate. An air sparging rate of 1.0 to 1.5 scfm will provide sufficient mixing. Spent resin from chemical separation contains DTPA (diethylenetriaminepentaacetic acid) residue, and the resin must be washed with 0.1M NH 4 OH to remove excess DTPA before dissolution. Gamma irradiation of resin up to 4 kW-hr/L did not change the dissolution rate significantly

  19. The role of cation exchange in controlling groundwater chemistry at Aspo, Sweden

    International Nuclear Information System (INIS)

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

    1995-01-01

    Construction-induced groundwater flow has resulted in the mixing of relatively dilute shallow groundwater with more concentrated groundwater at depth in the underground Hard Rock Laboratory (HRL) at Aespoe, Sweden. The observed compositional variation of the mixed groundwater cannot be explained using a conservative mixing model. The geochemical modeling package EQ3/6, to which a cation-exchange model was added, was used to simulate mixing between the two fluids. The results of modeling simulations suggest that cation exchange between groundwater and fracture-lining clays can explain the major element fluid chemistry observed in the HRL. The quantity of exchanger required to match simulated with observed fluid chemistry is reasonable and is consistent with the observed fracture mineralogy. This preliminary study establishes cation exchange as a viable mechanism for controlling the chemical evolution of groundwaters in a fracture-dominated dynamic flow system. This modeling study also strengthens their confidence in the ability to model the potential effects of fracture-lining minerals on the transport of radionuclides in a high level nuclear waste repository

  20. Synthesized cellulose/succinic anhydride as an ion exchanger. Calorimetry of divalent cations in aqueous suspension

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Julio C.P. [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP (Brazil); Silva Filho, Edson C. [LIMAV, Federal University of Piaui, 64049-550 Teresina, Piaui (Brazil); Santana, Sirlane A.A. [Departamento de Quimica/CCET, Universidade Federal do Maranhao, Av. dos Portugueses S/N, Campus do Bacanga, 65080-540 Sao Luiz, MA (Brazil); Airoldi, Claudio, E-mail: airoldi@iqm.unicamp.br [Institute of Chemistry, University of Campinas, UNICAMP, P.O. Box 6154, 13084-971 Campinas, SP (Brazil)

    2011-09-20

    Highlights: {yields} Synthetic route based on anhydride melting point. {yields} Cellulosic biopolymer/anhydride as ion exchanger. {yields} Calorimetry of cation exchange at solid/liquid interface. {yields} Favorable thermodynamic data of exchanging process. - Abstract: A synthetic route to a biopolymer/anhydride ion exchanger adds cellulose directly to molten succinic anhydride in a quasi solvent-free procedure. An amount of 3.07 {+-} 0.05 mmol of pendant groups incorporated onto the polymeric structure, which was characterized by elemental analysis, solid state carbon NMR, infrared, X-ray and thermogravimetry. The new polysaccharide is able to exchange cations from aqueous solution through a batchwise methodology, to obtain 2.46 {+-} 0.09 mmol g{sup -1} for divalent cobalt and nickel cations. The net thermal effects obtained from calorimetric titrations gave endothermic values of 3.81 {+-} 0.02 and 2.35 {+-} 0.01 kJ mol{sup -1}. The spontaneity of this ion-exchange process reflected in negative Gibbs energies and also a positive entropic contribution. These thermodynamic data at the solid/liquid interface suggests a favorable ion exchange process for this anchored biopolymer, for cation removal from the environment.

  1. Selective oxidation of propane over cation exchanged zeolites

    NARCIS (Netherlands)

    Xu, J.

    2005-01-01

    This thesis focuses on investigation of the fundamental knowledge on a new method for selective oxidation of propane with O2 at low temperature (< 100°C). The relation between propane catalytic selective oxidation and physicochemical properties of cation exchanged Y zeolite has been studied. An

  2. Isotopic enrichment of 15N by ionic exchange cromatography

    International Nuclear Information System (INIS)

    Trivelin, P.C.O.; Matsui, E.; Salati, E.

    1979-01-01

    The ionic exchange chromatographic method in columns of resin which is employed in the study of isotopic enrichment of 15 N is presented. Determinations are made of the isotopic separation constant for the exchange of isotopes 15 N and 14 N in the equilibrium involving ammonium hidroxide in the solution phase and ions NH 4 + adsorbed in cationic resins: Dowex 50W-X8 and X12, 100-200 mesh. Experiments are also conducted for determination of height of theoretical plates for situations of equilibrium of the NH 4 + band in two systems of resin's columns aimed at estimating the experimental conditions used. The isotopic analyses of nitrogen are carried out by mass spectrometry [pt

  3. Industrial scale chromatographic separation of valuable compounds from biomass hydrolysates and side streams

    Energy Technology Data Exchange (ETDEWEB)

    Saari, P.

    2011-06-15

    Carbohydrates are composed of a number of various monosaccharides, glucose being the most abundant. Some of the monosaccharides are valuable compounds used in the food and pharmaceutical industries. They can be separated from biomass hydrolysates e.g. by chromatographic methods. In this thesis, chromatographic separation of valuable compounds using ion exchange resins was studied on an industrial scale. Of special interest were rare monosaccharides in biomass hydrolysates. A novel chromatographic separation process was developed for fucose, starting from pre-processed spent sulfite liquor. The core of the process consists of three chromatographic separations with different types of ion exchange resins. Chromatographic separation of galactose was tested with three biomass hydrolysates; lactose, gum arabic and hemicellulose hydrolysates. It was demonstrated that also galactose can be separated from complex carbohydrate mixtures. A recovery process for arabinose from citrus pectin liquid residual and for mannose from wood pulp hydrolysate were also developed and experimentally verified. In addition to monosaccharides, chromatographic separation of glycinebetaine from vinasse was examined with a hydrogen form weak acid cation exchange resin. The separation involves untypical peak formation depending, for example, on the pH and the cation composition. The retention mechanism was found to be hydrogen bonding between glycinebetaine and the resin. In the experimental part, all four resin types - strong acid cation, strong base anion, weak acid cation and weak base anion exchange resins - were used. In addition, adsorption equilibria data of seven monosaccharides and sucrose were measured with the resins in sodium and sulfate forms because such data have been lacking. It was found out that the isotherms of all sugars were linear under industrial conditions. A systematic method for conceptual process design and sequencing of chromatographic separation steps were developed

  4. 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)

  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. Effect of Divalent Cations on RED Performance and Cation Exchange Membrane Selection to Enhance Power Densities.

    Science.gov (United States)

    Rijnaarts, Timon; Huerta, Elisa; van Baak, Willem; Nijmeijer, Kitty

    2017-11-07

    Reverse electrodialysis (RED) is a membrane-based renewable energy technology that can harvest energy from salinity gradients. The anticipated feed streams are natural river and seawater, both of which contain not only monovalent ions but also divalent ions. However, RED using feed streams containing divalent ions experiences lower power densities because of both uphill transport and increased membrane resistance. In this study, we investigate the effects of divalent cations (Mg 2+ and Ca 2+ ) on RED and demonstrate the mitigation of those effects using both novel and existing commercial cation exchange membranes (CEMs). Monovalent-selective Neosepta CMS is known to block divalent cations transport and can therefore mitigate reductions in stack voltage. The new multivalent-permeable Fuji T1 is able to transport divalent cations without a major increase in resistance. Both strategies significantly improve power densities compared to standard-grade CEMs when performing RED using streams containing divalent cations.

  7. Ion exchange equilibrium for some uni-univalent and uni-divalent reaction systems using strongly basic anion exchange resin Duolite A-102 D

    Directory of Open Access Journals (Sweden)

    R.S. Lokhande

    2008-04-01

    Full Text Available 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 as in the resin phase. The K values calculated for uni-univalent and uni-divalent anion exchange reaction systems was observed to increase with rise in temperature, indicating the endothermic exchange reactions having enthalpy values of 13.7, 38.0, 23.9, 22.9 kJ/mol, respectively.

  8. Corrosion of steel drums containing cemented ion-exchange resins as intermediate level nuclear waste

    Science.gov (United States)

    Duffó, G. S.; Farina, S. B.; Schulz, F. M.

    2013-07-01

    Exhausted ion-exchange resins used in nuclear reactors are immobilized by cementation before being stored. They are contained in steel drums that may undergo internal corrosion depending on the presence of certain contaminants. The objective of this work is to evaluate the corrosion susceptibility of steel drums in contact with cemented ion-exchange resins with different aggressive species. The corrosion potential and the corrosion rate of the steel, and the electrical resistivity of the matrix were monitored for 900 days. Results show that the cementation of ion-exchange resins seems not to pose special risks regarding the corrosion of the steel drums. The corrosion rate of the steel in contact with cemented ion-exchange resins in the absence of contaminants or in the presence of 2.3 wt.% sulphate content remains low (less than 0.1 μm/year) during the whole period of the study (900 days). The presence of chloride ions increases the corrosion rate of the steel at the beginning of the exposure but, after 1 year, the corrosion rate drops abruptly reaching a value close to 0.1 μm/year. This is probably due to the lack of water to sustain the corrosion process. When applying the results obtained in the present work to estimate the corrosion depth of the steel drums containing the cemented radioactive waste after a period of 300 years, it is found that in the most unfavourable case (high chloride contamination), the corrosion penetration will be considerably lower than the thickness of the wall of the steel drums. Cementation of ion-exchange resins does not seem to pose special risks regarding the corrosion of the steel drums that contained them; even in the case the matrix is highly contaminated with chloride ions.

  9. Formation of Aqueous MgUO2(CO3)32- Complex and Uranium Anion Exchange Mechanism onto an Exchange Resin

    International Nuclear Information System (INIS)

    Dong, Wenming; Brooks, Scott C

    2008-01-01

    The formation of and stability constants for aqueous Mg-UO2-CO3 complexes were determined using an anion exchange method. Magnesium concentration was varied (up to 20 mmol/L) at constant ionic strength (I = 0.101, 0.202, 0.304, 0.406, and 0.509 mol/kg NaNO3), pH = 8.1, total [U(VI)] = 10.4 mol/L under equilibrium with atmospheric CO2. The results indicate that only the MgUO2(CO3)32- complex is formed. The cumulative formation constant extrapolated to zero ionic strength is similar regardless of the activity correction convention used: log = 25.8 b 0.5 using Davies equation and = 25.02 b 0.08 using specific ion interaction theory (SIT). Uranium sorption onto the exchange resin decreased in the presence of Mg putatively due to the formation of MgUO2(CO3)32- that had a lower affinity for the resin than UO2(CO3)34-. Uranium sorption results are consistent with an equivalent anion exchange reaction between NO3- and UO2(CO3)34- species to retain charge neutrality regardless of Mg concentration. No Mg was associated with the anion exchange resin indicating that the MgUO2(CO3)32- complex did not sorb

  10. Synthesis and Characterization of Silicon Titanate as Cation Exchanger and Their Use in the Treatment of Radioactive Liquid Waste

    International Nuclear Information System (INIS)

    El-Naggar, I.M.; Belacy, N.; Mohamed, D.A.; Abou-Mesalam, M.M.

    1999-01-01

    Anew class of inorganic ion exchanger called crystalline silicon titanates has excellent chemical and radiation stability. The materials exhibited high selectivity for the ion exchange of cesium, strontium and several other radionuclides from highly acidic solutions. The ion exchange capacity was determined for Na +, Cs +, Co 2+ and Sr 2+ ions and found to be 1.17 , 1.9, 1.38 and 1.52 meq./g, respectively. Besides, the drying temperature of silicon titanates have a profound effect on the ion exchange capacities and distribution coefficient values of the above mentioned cations. Moreover, the studied results of distribution coefficient indicating the ability of separation of these radionuclides from radwaste solutions

  11. 1-Butanol absorption in poly(styrene-divinylbenzene) ion exchange resins for catalysis.

    Science.gov (United States)

    Pérez-Maciá, M A; Curcó, D; Bringué, R; Iborra, M; Rodríguez-Ropero, F; van der Vegt, N F A; Aleman, Carlos

    2015-12-21

    The swelling behaviour of poly(styrene-co-divinylbenzene), P(S-DVB), ion exchange resins in 1-butanol (BuOH) has been studied by means of atomistic classical molecular dynamics simulations (MD). The topological characteristics reported for the resin in the dry state, which exhibited complex internal loops (macropores), were considered for the starting models used to examine the swelling induced by BuOH contents ranging from 10% to 50% w/w. Experimental measurements using a laser diffraction particle size analyzer indicate that swelling causes a volume variation with respect to the dry resin of 21%. According to MD simulations, such a volume increment corresponds to a BuOH absorption of 31-32% w/w, which is in excellent agreement with the indirect experimental estimation (i.e. 31% w/w). Simulations reveal that, independently of the content of BuOH, the density of the swelled resin is higher than that of the dry resin, evidencing that the alcohol provokes important structural changes in the polymeric matrix. Thus, BuOH molecules cause a collapse of the resin macropores when the content of alcohol is ≤20% w/w. In contrast, when the concentration of BuOH is close to the experimental value (∼30% w/w), P(S-DVB) chains remain separated by pores faciliting the access of the reactants to the reaction centers. On the other hand, evaluation of both bonding and non-bonding interactions indicates that the mixing energy is the most important contribution to the absorption of BuOH into the P(S-DVB) resin. Overall, the results displayed in this work represent a starting point for the theoretical study of the catalytic conversion of BuOH into di-n-butyl ether in P(S-DVB) ion exchange resins using sophisticated electronic methods.

  12. Development of a novel resin-based dental material with dual biocidal modes and sustained release of Ag+ ions based on photocurable core-shell AgBr/cationic polymer nanocomposites.

    Science.gov (United States)

    Cao, Weiwei; Zhang, Yu; Wang, Xi; Chen, Yinyan; Li, Qiang; Xing, Xiaodong; Xiao, Yuhong; Peng, Xuefeng; Ye, Zhiwen

    2017-07-01

    Research on the incorporation of cutting-edge nano-antibacterial agent for designing dental materials with potent and long-lasting antibacterial property is demanding and provoking work. In this study, a novel resin-based dental material containing photocurable core-shell AgBr/cationic polymer nanocomposite (AgBr/BHPVP) was designed and developed. The shell of polymerizable cationic polymer not only provided non-releasing antibacterial capability for dental resins, but also had the potential to polymerize with other methacrylate monomers and prevented nanoparticles from aggregating in the resin matrix. As a result, incorporation of AgBr/BHPVP nanocomposites did not adversely affect the flexural strength and modulus but greatly increased the Vicker's hardness of resin disks. By continuing to release Ag + ions without the impact of anaerobic environment, resins containing AgBr/BHPVP nanoparticles are particularly suitable to combat anaerobic cariogenic bacteria. By reason of the combined bactericidal effect of the contact-killing cationic polymers and the releasing-killing Ag + ions, AgBr/BHPVP-containing resin disks had potent bactericidal activity against S. mutans. The long-lasting antibacterial activity was also achieved through the sustained release of Ag + ions due to the core-shell structure of the nanocomposites. The results of macrophage cytotoxicity showed that the cell viability of dental resins loading less than 1.0 wt% AgBr/BHPVP was close to that of neat resins. The AgBr/BHPVP-containing dental resin with dual bactericidal capability and long term antimicrobial effect is a promising material aimed at preventing second caries and prolonging the longevity of resin composite restorations.

  13. The role of cell walls and pectins in cation exchange and surface area of plant roots.

    Science.gov (United States)

    Szatanik-Kloc, A; Szerement, J; Józefaciuk, G

    2017-08-01

    We aimed to assess role of cell walls in formation of cation exchange capacity, surface charge, surface acidity, specific surface, water adsorption energy and surface charge density of plant roots, and to find the input of the cell wall pectins to the above properties. Whole roots, isolated cell walls and the residue after the extraction of pectins from the cell walls of two Apiaceae L. species (celeriac and parsnip) were studied using potentiometric titration curves and water vapor adsorption - desorption isotherms. Total amount of surface charge, as well as the cation exchange capacity were markedly higher in roots than in their cell walls, suggesting large contribution of other cell organelles to the binding of cations by the whole root cells. Significantly lower charge of the residues after removal of pectins was noted indicating that pectins play the most important role in surface charge formation of cell walls. The specific surface was similar for all of the studied materials. For the separated cell walls it was around 10% smaller than of the whole roots, and it increased slightly after the removal of pectins. The surface charge density and water vapor adsorption energy were the highest for the whole roots and the lowest for the cell walls residues after removal of pectins. The results indicate that the cell walls and plasma membranes are jointly involved in root ion exchange and surface characteristics and their contribution depends upon the plant species. Copyright © 2017 Elsevier GmbH. All rights reserved.

  14. Removal of Pb2+ from aqueous solutions by a high-efficiency resin

    International Nuclear Information System (INIS)

    Guo, Hao; Ren, Yongzheng; Sun, Xueliang; Xu, Yadi; Li, Xuemei; Zhang, Tiancheng; Kang, Jianxiong; Liu, Dongqi

    2013-01-01

    The removal of Pb 2+ from aqueous solution by 732 cation-exchange resin in sodium type (732-CR) has been studied in batch experiments at varying pH (2.0–8.0), Pb 2+ concentration (50–200 mg/L), contact time (5–300 min), temperature (288–308 K) and resin dose (0.125–0.75 g/L). The experimental data show that the ion-exchange process was dependent on pH and temperature, the optimal exchange capacity was found at pH 4.0, and higher temperature was beneficial to lead sorption. Kinetic data indicate that the ion-exchange process followed a pseudo-first order model. The equilibrium exchange capacity could be reached at approximately 4 h, and the maximum sorption capacity of Pb 2+ at pH 4.0 was 396.8 mg/g resin. The equilibrium data were evaluated with Langmuir and Freundlich model, and were best fitted with Langmuir model. The thermodynamic parameters for removal of Pb 2+ indicate that the reaction was spontaneous and endothermic. Additionally, column tests were conducted by using both synthetic solution and effluents from lead battery industry. The regeneration of resin was performed for two sorption-regeneration cycles by 1 M NaOH, and the results show that effective regeneration was achieved by this method.

  15. 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.

  16. Sustainable nitrate-contaminated water treatment using multi cycle ion-exchange/bioregeneration of nitrate selective resin.

    Science.gov (United States)

    Ebrahimi, Shelir; Roberts, Deborah J

    2013-11-15

    The sustainability of ion-exchange treatment processes using high capacity single use resins to remove nitrate from contaminated drinking water can be achieved by regenerating the exhausted resin and reusing it multiple times. In this study, multi cycle loading and bioregeneration of tributylamine strong base anion (SBA) exchange resin was studied. After each cycle of exhaustion, biological regeneration of the resin was performed using a salt-tolerant, nitrate-perchlorate-reducing culture for 48 h. The resin was enclosed in a membrane to avoid direct contact of the resin with the culture. The results show that the culture was capable of regenerating the resin and allowing the resin to be used in multiple cycles. The concentrations of nitrate in the samples reached a peak in first 0.5-1h after placing the resin in medium because of desorption of nitrate from resin with desorption rate of 0.099 ± 0.003 hr(-1). After this time, since microorganisms began to degrade the nitrate in the aqueous phase, the nitrate concentration was generally non-detectable after 10h. The average of calculated specific degradation rate of nitrate was -0.015 mg NO3(-)/mg VSS h. Applying 6 cycles of resin exhaustion/regeneration shows resin can be used for 4 cycles without a loss of capacity, after 6 cycles only 6% of the capacity was lost. This is the first published research to examine the direct regeneration of a resin enclosed in a membrane, to allow reuse without any disinfection or cleaning procedures. Copyright © 2013 Elsevier B.V. All rights reserved.

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

    Energy Technology Data Exchange (ETDEWEB)

    Aleman, S. [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)

    2007-06-27

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

  18. Microbial activity in an acid resin deposit: Biodegradation potential and ecotoxicology in an extremely acidic hydrocarbon contamination

    International Nuclear Information System (INIS)

    Kloos, Karin; Schloter, Michael; Meyer, Ortwin

    2006-01-01

    Acid resins are residues produced in a recycling process for used oils that was in use in the forties and fifties of the last century. The resin-like material is highly contaminated with mineral oil hydrocarbons, extremely acidic and co-contaminated with substituted and aromatic hydrocarbons, and heavy metals. To determine the potential for microbial biodegradation the acid resin deposit and its surroundings were screened for microbial activity by soil respiration measurements. No microbial activity was found in the core deposit. However, biodegradation of hydrocarbons was possible in zones with a lower degree of contamination surrounding the deposit. An extreme acidophilic microbial community was detected close to the core deposit. With a simple ecotoxicological approach it could be shown that the pure acid resin that formed the major part of the core deposit, was toxic to the indigenous microflora due to its extremely low pH of 0-1. - Acidity is the major toxic factor of the extremely hydrophobic and acidic mixed contamination found in an acid resin deposit

  19. Determination of Ni{sup 2+} using an equilibrium ion exchange technique: Important chemical factors and applicability to environmental samples

    Energy Technology Data Exchange (ETDEWEB)

    Worms, Isabelle A.M. [CABE - Analytical and Biophysical Environmental Chemistry, University of Geneva, 30 quai Ernest Ansermet 1211 Geneva 4 (Switzerland); Wilkinson, Kevin J. [Department of Chemistry, University of Montreal C.P. 6128, succursale Centre-ville Montreal, H3C 3J7 (Canada)], E-mail: KJ.Wilkinson@umontreal.ca

    2008-05-26

    In natural waters, the determination of free metal concentrations is a key parameter for studying bioavailability. Unfortunately, few analytical tools are available for determining Ni speciation at the low concentrations found in natural waters. In this paper, an ion exchange technique (IET) that employs a Dowex resin is evaluated for its applicability to measure [Ni{sup 2+}] in freshwaters. The presence of major cations (e.g. Na, Ca and Mg) reduced both the times that were required for equilibration and the partition coefficient to the resin ({lambda}{sup '}{sub Ni}). IET measurements of [Ni{sup 2+}] in the presence of known ligands (citrate, diglycolate, sulfoxine, oxine and diethyldithiocarbamate) were verified by thermodynamic speciation models (MINEQL{sup +} and VisualMINTEQ). Results indicated that the presence of hydrophobic complexes (e.g. Ni(DDC){sub 2}{sup 0}) lead to an overestimation of the Ni{sup 2+} fraction. On the other hand, [Ni{sup 2+}] measurements that were made in the presence of amphiphilic complexes formed with humic substances (standard aquatic humic acid (SRHA) and standard aquatic fulvic acid (SRFA)) were well correlated to free ion concentrations that were calculated using a NICA-DONNAN model. An analytical method is also presented here to reduce the complexity of the calibration (due to the presence of many other cations) for the use of Dowex equilibrium ion exchange technique in natural waters.

  20. 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