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1

Natural zeolite as a replacement for resin in the cation exchange process of cesium on post-irradiated nuclear fuel

Ginting Aslina Br., Siti Amini, Noviarty, Yanlinastuti, Nugroho Arif, Boybul

Nukleonika

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2021

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Vol. 66, No. 1

11--19

EN

Characterization of natural salts from Bayah, Lampung, and Tasikmalaya, Indonesia has been carried out as a substitute for synthetic resins. The characteristics include zeolite activation with NH4Cl, and heated at 200C, the bond stability test of 137Cs-zeolite, chemical composition analysis, surface area, pore size, analysis of Cs cation exchange capacity (CEC), diffusion coeffi cient (Di), activation energy (Ea), and absorption of three zeolites. To do this, pipette 50 l of a standard solution of 137Cs from the National Institute of Standards and Technology (NIST), put in, 2 ml of 0.1 N HCl, and then add 1 g of zeolite and stir each for 1, 2, 3, 4, 5, and 24 h. Based on this stirring time, the 137C isotope will exchange ions with NH4-zeolite to 137Cs-zeolite in the solid phase. The content of 137Cs in 137Cs-zeolites (solid phase) was analysed using a gamma spectrometer. The results of the chemical composition analysis showed that the character of zeolite from Lampung has a Si/Al ratio, with a CEC value of 1.448 mEq/g which is greater than Bayah and Tasikmalaya, while the Di and Ea values for the three select types were obtained almost the same. Moreover, the stability test of the Cs ion bond with zeolite showed no signifi cant release of Cs ions from the zeolite structure. It can be concluded that the three soloists tested that the zeolite from Lampung has better characters. The results of 137Cs isotope separation in 150 l of U3Si2/Al fuel solution post-irradiation using zeolite from Lampung and Dowex resins obtained almost the same recovery around 98–99%, so it can be concluded that zeolite from Lampung can be used as a substitute for synthetic resin in the cation exchange process for the 137Cs isotope in nuclear fuel post-irradiated.

2

Wymiana kationowa w środowisku kwaśnym wybranych pierwiastków na powierzchni sorbentów wytworzonych na bazie modyfikowanego węgla brunatnego

Stempkowska A., Izak P., Mastalska-Popławska J.

Gospodarka Surowcami Mineralnymi

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2017

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T. 33, z. 1

139--149

PL

Przeprowadzono badania sorpcji i desorpcji wybranych kationów Na+, Ca2+, Mg2+, Mn2+, Cu2+, Cr3+, przez materiały wytworzone na bazie węgla brunatnego. Modyfikacja chemiczna materiału sorbentowego polegała na rozdrobnieniu z udziałem różnych związków nieorganicznych w tym z polimerami organicznymi. Próbki po modyfikacji chemicznej poddano działaniu podwyższonej temperatury przez kilka godzin. W celach porównawczych przeanalizowano także próbki surowego węgla brunatnego bez i po oczyszczeniu, bowiem wyseparowane czyste kwasy huminowe z węgla brunatnego są znane z największej kationowej pojemności wymiennej. Pojemność jonową określano w warunkach statycznych, mierząc różnicę stężenia kationów w sorbacie przed i po sorpcji (etap I), a następnie po przemyciu sorbentu (etap II) wodą destylowaną (A), oraz po procesie desorpcji kwasem solnym (B). Badania wykazały, że sorbenty na bazie zmodyfikowanego węgla brunatnego wykazały dość znaczne pojemności wymienne w granicach od 270−450 meq/100 g, w przypadku etapu pierwszego, i od 90−200 meq/100 g w przypadku etapu drugiego. Stwierdzono także, że najwyższą pojemność wymienną posiada oczyszczony kwas huminowy 450/200 meq/100 g, a najniższą modyfikat węgla brunatnego otrzymany w temperaturze 250°C. Pomiary desorpcji wykazały, że około 10% kationów jest wymywanych przez wodę destylowaną, pozostałość desorbuje się pod wpływem 10% kwasu solnego, jednakże suma kationów jest zgodna z pomiarem etapu drugiego. Powinowactwo sorpcyjne względem poszczególnych kationów jest różne. W przypadku pomiarów różnicy stężeń sorbenty modyfikowane wykazują najwyższe powinowactwo sorpcyjne względem wapnia, natomiast niemodyfikowany surowy węgiel brunatny względem chromu. Badania desorpcji wykazały, że najwyższy wpływ na powinowactwo sorpcyjne ma wartościowość kationu.

EN

Studies on the sorption and desorption of selected Na+, Ca2+, Mg2+, Mn2+, Cu2+ and Cr3+ cations by materials based on modified brown coal were carried out. The chemical modification of the sorbent material consisted of grinding involving different inorganic substances and organic polymers. Samples were subjected to chemical modification at elevated temperatures for several hours. For comparative purposes, as apart from brown coal, pure humic acids are known for the highest cations exchange capacity, samples of brown coal before and after purification were also analyzed. The ion capacity was determined under static conditions, measuring the difference in the concentration of cations in the sorbent before and after sorption and then after rinsing the sorbent with distilled water (A), and after the desorption process with hydrochloric acid (B). Studies have shown that sorbents based on modified brown coal have rather significant exchange capacities in the range of 270−450 meq/100 g for the first stage and 90−200 meq/100 g for the second stage. It was also found that purified humic acid (450−200 meq/100 g) has the highest exchange capacity and modified brown coal obtained at 250°C has the lowest. T he measurement of desorption showed that approximately 10% of the cations are already leached by distilled water and the residue is desorbed under the influence of 10% hydrochloric acid, but the total amount of cations is compatible with the measurement process of the second stage. The sorption affinity to various cations is different. In the case of the sorption measurements, modified sorbents show the highest sorption affinity with respect to calcium, while the unmodified raw brown coal with respect to chromium. The next stage of the measurement showed that the valence of the cation has the highest impact on the sorption affinity.

3

Study on preferential selectivity of nuclear grade resin Indion-223 towards some bivalent ions

Singare P. U., Mohammed A. L. K., Dixit N. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 15

11--21

EN

In the present paper attempts are made to understand the selectivity of nuclear grade cation exchange resin Indion-223 in H+ form towards Ca2+ and Mg2+ bivalent ions in the solution based on thermodynamic concept. It was observed that with rise in temperature the equilibrium constant K values for H+/Ca2+ uni-bivalet ion exchange reactions increases from 0.000397 to 0.000639. Similarly for H+/Mg2+ uni-bivalet ion exchange reactions the equilibrium constant K values increases from 0.000177 to 0.000333. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 38.92 and 51.46 kJ/ mol respectively. The difference in K values and enthalpy values were used to predict the selectivity behaviour of the resin towards the Ca2+ and Mg2+ bivalent ions in the solution. The thermodynamic concept of the present study can be applied to understand the selectivity behaviour of different nuclear as well as non-nuclear grade resins towards wide range of ionic species present in the exchanging liquid medium.

4

Study of uni-univalent H+/K+ and uni-bivalent H+/Mg2+ ion exchange reactions using nuclear grade resin Indion-223

Singare P. U., Mohammed A. K. L., Dixit N. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 14, iss. 2

231-239

EN

In the present paper the uni-univalent and uni-bivalent ion exchange reactions were investigated using nuclear grade anion exchange resin Indion-223 in H+ form. For both H+/K+ uni-univalet ion exchange reactions and H+/Mg2+ uni-bivalet ion exchange reactions, the equilibrium constant K values increases from 0.01710 to 0.02374 and from 0.000177 to 0.000333 respectively as the reaction temperature rises from 35.0 °C to 45.0 °C. The increase in K values with temperature suggest endothermic ion exchange reactions having the enthalpy change values of 22.72 and 51.46 kJ/ mol respectively. The results of such studies will help in selection of suitable ion exchange resins in order to bring about efficient separation of different ionic species present in the waste water effluents released from nuclear as well as chemical process industries.

5

Ion exchange equilibrium studies of uni-univalent H+/Na+ and uni-bivalent H+/Mg2+ ion exchange reactions using nuclear grade resin Indion-223

Singare P. U., Mohammed A. L. K., Dixit N. N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 14, iss. 2

199-207

EN

In the present investigation the uni-univalent and uni-bivalent ion exchange reactions were studied using nuclear grade anion exchange resin Indion-223 in H+ form. It was observed that for H+/Na+ uni-univalet ion exchange reaction, with rise in temperature the equilibrium constants K values increases from 0.01389 to 0.01855. Similarly increase in K values was observed from 0.000177 to 0.000333 for H+/Mg2+ uni-bivalet ion exchange reaction. The increase in equilibrium constant values with rise in temperature indicate endothermic ion exchange reactions having the enthalpy change values of 25.55 and 51.46 kJ/ mol respectively. It is expected that the present study will provide valuable information in order to decide about the selection of those resins for efficient separation of various ionic species present in the industrial waste water effluents.

6

Badania składu izotopowego litu metodą TIMS

Dąbek J., Hałas S., Pacek A.

Elektronika : konstrukcje, technologie, zastosowania

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2011

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Vol. 52, nr 8

74-77

PL

Artykuł przedstawia metodę wydzielania litu z roztworów wodnych na kolumnie kationowymiennej oraz wyniki pomiarów stosunku izotopowego litu ⁷Li/⁶Li w uzyskanych próbkach metodą TIMS (Thermal Ionisation Mass Spectrometry). Według tej metody zostały przebadane próbki wody morskiej pochodzącej z Morza Śródziemnego, próbki wody mineralnej pochodzącej z odwiertów Zuber I i Zuber II w Krynicy Zdroju oraz próbka osadu z wody Zuber I. Wartości σ⁷Li dla badanych próbek uzyskane zostały z powtarzalnością rzędu jednego promila.

EN

The paper presents the method of lithium extraction from water solutions on cation exchange column and the determination of its isotope ratio by thermal ionization mass spectrometry. According to this method the following samples have been investigated: seawater from Mediterranean Sea, mineral water from Zuber I and Zuber II boreholes in Krynica Spa, and a sediment sample from Zuber I water. The values of σ⁷Li for all the investigated samples were achieved with reproducibility of order of 1 ‰.

7

The sorption of copper ions by gyrolite in alkaline solution

Bankauskaite A., Baltakys K.

Materials Science Poland

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2009

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Vol. 27, No. 3

899--908

EN

Sorption of copper ions by synthetic pure gyrolite (CaO/SiO2 = 0.66; 96 h; 200 °C) in alkaline solutions was examined. When the initial concentration of Cu2+ ions is 1 g/dm3, the cation exchange capacity of the gyrolite is 100 mg Cu2+/g after 360 min of sorption at 25 °C. It has been proved that the cation exchange capacity of gyrolite depends on the concentration of copper ions in the Cu(NO3)2 solution, because a fivefold increase of the concentration (from 1.0 to 5.0 g/dm3) reduces the duration of the ion exchange reaction by a factor of three (from 15 min to 5 min). In solutions with higher initial concentrations of Cu2+ ions (10.0 and 20.0 g/dm3), the sorption proceeds more intensively and all the copper ions are adsorbed in 1 min. It should be noted that the cation exchange reactions are reversible in alkaline solution, because nearly 90% of the copper ions are adsorbed in a physical process, while the remaining part of the cation exchange process takes place in a chemical reaction. Furthermore, the crystal structure of gyrolite is stable in alkaline solution. The products of sorption were characterized by X-ray diffraction, thermogravimetry-differential scanning calorimetry and Fourier-transform infrared spectroscopy methods.

8

Preparation of polysilic acid sols by ion exchange method

Malewski W., Krysztafkiewicz A., Jesionowski T.

Physicochemical Problems of Mineral Processing

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2006

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Vol. 40

265-273

EN

In the study application of the macroporous ionite, Amberlyst® 15 (Merck), was tested in the process of production of dilute solutions of silicic acid sols. The process of ion exchange was conducted in a periodic reactor employing batch technique at the temperature of 45 C or 85 C. The products involved clear and stable solutions of sols of mean SiO2 concentrations of 4.31, 4.72, 6.34 and 6.46 wt.%. A two-stage technique for ionite recovery was also worked out.

PL

W pracy przetestowano makroporowaty jonit Amberlyst® 15 (prod. Merck) w procesie otrzymywania rozcieńczonych roztworów zolu kwasu krzemowego. Proces wymiany jonowej prowadzono w reaktorze okresowym metodą batch w temp. 45 i 85oC. Produktami były klarowne roztwory zoli o średnich stężeniach SiO2 4,31; 4,72; 6,34; 6,46 %wag. Opracowano również dwuetapową metodę regeneracji jonitu.

9

Ion exchange by means of Donnan dialysis as a pretreatment process before electrodialysis.

Wiśniewski J.

Environment Protection Engineering

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2006

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Vol. 32, nr 2

47-66

EN

The author applied Donnan dialysis in order to remove troublesome anions (SO42- and HCO3-) or cations (Ca2+, Mg2+) from water solutions before their electrodialytic desalination. As the result of Donnan dialysis (with the Neosepta AFN membrane), molar share of troublesome anions (SO42- and HCO3-) decreased to 4.3% of all anions. The cation exchange was responsible for a decrease in the molar share of Ca2+ and Mg2+ to 5.5% of all cations in the solution. Due to the change of solution ionic composition, a number of advantageous phenomena were observed during electrodialytic desalination: the increase in the limiting current density, higher rate of the salt removal (Ł20%) and lower consumption of energy necessary for the transport of a given amt. of salt (Ł3 times). It was concluded that Donnan dialysis with the anion-exchange membrane (Neosepta AFN) was an advantageous pretreatment process before electrodialysis because the fluxes of the removed anions were even twice as high as those observed with the cation-exchange membrane for cation removal.

PL

Dializę Donnana zastosowano do usuwania uciążliwych anionów ( i ) lub kationów (Ca2+, Mg2+) z roztworów wodnych przed ich odsalaniem metodą elektrodializy. W wyniku procesu z membraną anionowymienną (Neosepta AFN) udział molowy uciążliwych anionów ( i ) zmniejszył się do 4,3% wszystkich anionów. Dzięki wymianie kationów (z membraną Selemion CMV) zmniejszył się udział molowy kationów Ca2+, Mg2+ do 5,5% wszystkich kationów. Wskutek zmiany składu jonowego roztworu zaobserwowano wiele korzystnych zjawisk podczas elektrodialitycznego odsalania takich jak: wzrost granicznej gęstości prądu, większą szybkość usuwania soli (do 20%) oraz mniejsze zużycie energii potrzebnej do transportu określonej ilości soli (do trzech razy). Stwierdzono, że dializa Donnana z membraną anionowymienną (Neosepta AFN) jest korzystniejszym procesem wstępnego przygotowania wody przed elektrodializą niż ten sam proces z membraną kationowymienną, ponieważ strumienie usuwanych anionów są nawet 2 razy większe od strumieni kationów przenoszonych przez membranę kationowymienną.