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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

Rapid estimation of environmental radioactivity surrounding Xiangshan uranium deposits, Jiangxi province, Eastern China

Gan N., Cen K., Ye R., Li T.

Nukleonika

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2018

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Vol. 63, No. 4

113--121

EN

The surveys of terrestrial gamma dose rate, radon concentration indoor and in water and specific activity of radionuclides of soil were carried out in 14 villages and a town in Xiangshan uranium deposit and surrounding area, Jiangxi province, Eastern China, in 2017–2018, using a scintillator dosemeter, an ionization chamber and a high-purity germanium gamma spectrometer to study radiation status in these places after remediation. A radioactive hot spot was discovered in a village near the mining office, where specific activity of 238U, 226Ra, 232Th and 137Cs of soil was as high as 1433 ± 76 Bq/kg, 1210 ± 62 Bq/kg, 236 ± 13 Bq/kg and 17 ± 1.1 Bq/kg, respectively. The dose rate on a waste rock heap was about 2423 nGy/h. Approximately 50% of the houses in a village near the uranium mining site had radon concentrations that exceeded 160 Bq/m3 . There was a significant positive correlation between indoor radon concentration and outdoor gamma dose rate (R2 = 0.7876). The abnormal radon concentration was observed in a rising spring sample providing residents with tap water up to 127.1 Bq/l. Four tap water samples and three of five well water samples exceeded the limit of radon concentration of drinking water in China (11.1 Bq/l). The mean annual effective doses from gamma dose rate data were 0.86 mSv/y and 1.13 mSv/y for indoor radon. The study shows that there are some radioactively contaminated places surrounding the Xiangshan uranium mine. The local outdoor dose rate averages may be used to estimate local indoor radon concentrations.

3

Katalizatory kobaltowo-molibdenowe domieszkowane cezem do syntezy amoniaku

Moszyński D., Adamski P., Pełech I., Arabczyk W.

Przemysł Chemiczny

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2015

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T. 94, nr 8

1399-1403

PL

Badano katalizatory kobaltowo-molibdenowe domieszkowane cezem (0,25–3% mas. Cs) w procesie syntezy amoniaku. W katalizatorach tych zidentyfikowano dwie fazy krystaliczne azotków kobaltu i molibdenu: Co₂Mo₃N oraz Co₃Mo₃N. Wykazano, że materiały te charakteryzują się dużą aktywnością w procesie syntezy amoniaku. Optymalną aktywność katalityczną uzyskano dla katalizatorów zawierających 1,7% mas. cezu. Na podstawie testu starzenia termicznego wykazano, że dochodzi do częściowego spiekania krystalitów fazy repeatedly detd. Thermal treatment resulted in sintering of crystallite Co₃Mo₃N phase and decreasing the activity of catalysts.N oraz zmniejszenia powierzchni właściwej. W rezultacie zmniejsza się aktywność katalizatorów.

EN

Co-Mo catalysts contg. Cs (0.25–3.0% by mass) were obtained by redn. of precursors with NH₃ at 700°C. The precursors were derived from aq. solns. of (NH₄)₆Mo₇O₂₄, Co(NO₃)₂ and CsOH. The anal. of catalysts by X-ray diffraction and anal. of the diffraction profiles by Rietveld method showed the presence of Co₂Mo₃N and Co₃Mo₃N phases depending on the content of Cs in the catalyst. Activities of the catalysts were tested under lab. Conditions of the synthesis of NH₃ at 400°C and 10 MPa. The reaction rate const. was detd. by measuring the flow of the reaction gases and NH₃ concns. The highest activity was achieved for the catalyst contg. Cs 1.7% by mass. The catalysts used for the activity detns. were then subjected to aging (650°C, 18 h) and their activity was repeatedly detd. Thermal treatment resulted in sintering of crystallite Co₃Mo₃N phase and decreasing the activity of catalysts.

4

Sorption and migration of Cs, Sr, and Eu in gypsum - groundwater system

Alhassanieh O., Mrad O., Ajji Z.

Nukleonika

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2012

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Vol. 57, No. 1

125-131

EN

The distribution of 137Cs, 152Eu, and 85Sr in a solid/aqueous system, gypsum in contact with groundwater, was investigated using gamma-spectrometry. The sorption and migration of the radionuclides were investigated. The aqueous phase was characterized using instrumental neutron activation analysis (INAA) and high performance liquid chromatography (HPLC). The solid phases were characterized using X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The investigations included three kinds of gypsum: mineral, commercial, and own prepared gypsum. The influence of some parameters on sorption/migration of the radionuclides were studied, such as contact time, pH, and concentrations of concurrent elements. The effect of element concentration was also investigated. The results show the ability of gypsum to keep Sr and Eu in the solid phase in all three cases. The incorporation of Cs in the solid phase depends on the conditions and used materials, and varies between 93 and 97%.

5

Migration of strontium, cesium, europium and uranium from poly(methyl styrene)- and polystyrene - phosphate composites prepared using gamma radiation

Alhassanieh O., Ajji Z.

Nukleonika

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2012

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Vol. 57, No. 3

369-374

EN

Composites consisting of natural phosphate powder and two monomers (styrene or methyl styrene) have been prepared by means of gamma irradiation. The polymerization reaction was followed up using a thermogravimetric analyzer (TGA) to determine the conversion of the polymerization. Differential scanning calorimeter (DSC) was used to locate and determine the glass transition temperature (Tg) of the prepared samples. The distribution of 137Cs, 152Eu, 85Sr and 238U in a solid-aqueous system, composites of phosphate-poly(methyl styrene) and of phosphate-polystyrene in contact with groundwater, was investigated using alfa-spectrometry and fluorometry. The effects of contact time, pH, and the concentration of concurrent element (Ca) were studied. The results were compared with earlier results with phosphate alone in the solid phase. The ability of the produced composites to keep the studied radioisotopes in the solid phase is much higher than in the mineral phosphate. This improvement is more remarkable for strontium and cesium than for europium and uranium, due to their high element ratio in the solid phase in phosphate experiments.

6

Effect of energy pooling collisions in formation of a cesium plasma by continuous wave resonance excitation

Mahmoud M. A., Gamal Y. E. E.

Optica Applicata

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2010

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Vol. 40, nr 1

129--141

EN

The generation of plasma in cesium vapor excited by cw laser is investigated theoretically. We have developed a computational model which quantitatively explains the laser power dependences of electron energy distribution function (EEDF) and the level population densities which were created during the interaction. The energy spectra of the electrons emerging from the interaction show that the mechanisms by which electrons gain energy through the resonant system can significantly increase the density of the resonant plasma. The nonlinear behaviour of the ion current suggests that the plasma formation is initiated via collisional ionization and collisional excitation, such as associative ionization, Penning ionization, or photoionization as well as energy pooling collisions.The Cs - Cs atom collisions play important role in the formation of a highly Cs plasma with the use of a relatively low power laser to excite a resonance transition. A comparison between the behaviour of the calculated ion current as a function of a laser power is proved to be a reasonable agreement with that measured by Pappas et al. (Appl. Spectrosc. 54, 2000, p. 1245). The results may be useful in designing and developing cw metal vapor lasers.

7

Nuclear waste management with the use of calixcrowns in the aspect of cesium removal

Mianowska B., Śliwa W.

Prace Naukowe. Chemia i Ochrona Środowiska / Akademia im. Jana Długosza w Częstochowie

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2009

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Vol. 13

55-61

EN

Examples of calixcrowns useful in cesium removal from nuclear waste are given along with their synthetic approaches and complexation properties. Cesium extraction procedure from alkali metal ions mixtures is applying ionic liquids also presented.

PL

Podano przykłady kaliksarenoeterów koronowych stosowanych w usuwaniu jonów cezu z odpadów nuklearnych, omawiając ich syntezy i właściwości kompleksujące. Przedstawiono również procesy ekstrakcji cezu z mieszanin jonów litowców z użyciem cieczy jonowych.

8

Plutonium and 137Cs in forest litter: an approximate map of plutonium from Chernobyl deposition in North-eastern and Eastern Poland

Brudecki K., Suwaj J., Mietelski J. W.

Nukleonika

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2009

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Vol. 54, No. 3

199-209

EN

The present article contains information about the activities and origin of 137Cs, 238Pu and 239+240Pu in the North-eastern Poland. Analyzed samples were collected in 59 locations where forest litter A0 and humus A1 were collected in 1991. An approximate map of the Chernobyl fallout component 239+240Pu was prepared on the basis of received results. The largest Chernobyl 239+240Pu contamination occurred in north-eastern and eastern part of the investigated area, reaching 22.1š1.6 Bqźm–2.

9

Studies on concentration of some heavy metals and strontium 90Sr and cesium 137Cs isotopes in bottom sediments of selected lakes of Łęczyńsko-Włodawskie Pojezierze

Solecki J., Reszka M., Chibowski S.

Nukleonika

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2006

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Vol. 51,suppl.2

33-37

EN

Research on concentration of radionuclides and heavy metals in bottom sediments of three different lakes is presented. The lakes were located in the vicinity of the National Park in the Lublin (Poland) region. Bottom sediments were collected from various depths. In all studied sediment, sample concentration of 90Sr and 137Cs isotopes ranged from 2.07 11.76 to 5.67 67.7 Bq/kg, respectively. The amount of radioactive 137Cs increased with depth of the lake. The same dependence for 90Sr was not observed. The level of radioactivity originated from natural isotopes was much lower in bottom sediments than that measured in related soils. Most of radioactivity in bottom sediments comes from anthropogenic isotopes.

10

Calixarenes as alkali metal ions receptors

Śliwa W.

Chemistry-Didactics-Ecology-Metrology

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2001

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R. 6, NR 1-2

9--15

EN

Selected calixarenes useful as alkali metal ions receptors are described. Calixarenes, calixcrowns and callx-bis-crowns are presented, along with their application possibilities, e.g. radiocesium removal, as well as synthetic approaches.

PL

Opisano wybrane kaliksareny użyteczne jako receptory jonów litowców. Omówiono kaliksareny, kaliksareno-etery koronowe i kaliksareno-bis-etery koronowe, opisujac ich możliwości zastosowań, np. w celu usuwania radiocezu, oraz metody syntezy.

11

Structural studies of cesium and strontium exchanged zeolites.

Miecznikowski A.

Prace Naukowe Instytutu Chemii i Technologii Nafty i Węgla Politechniki Wrocławskiej. Konferencje

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1999

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Vol. 9, nr 56

285-290

EN

The cesium and strontium were exchanged by faujasite type and natural clinoptilolite and synthetic mordenite zeolites from cesium and strontium nitrate aqueous solution. The contents of cesium and strontium removed by zeolites from CsNO3 and Sr(NO3)2 aqueous solutions were measured by Atomic Emission Spectroscopy Induced Coupled Plasma. The Fourier Transform Far Infrared Spectroscopy were applied to tentative determination of position of cations in framework structure of zeolites.

PL

Z wzorcowych roztworów wodnych azotanów cezu i strontu usuwano cez i stront za pomocą zeolitów CaA, NaX, klinoptilolitu i modernitu. Zeolity badane metodą proszkowej analizy rentgenograficznej miały wysoki stopień krystaliczności. Stwierdzono metodą Emisyjnej Spektometrii Atomowej, że największa ilość cezu usuwana z roztworów wodnych ich azotanów jest za pomocą sodowego zeolitu X, następnie zeolitów klinoptilolitu i modernitu, natomiast największa ilość strontu usuwana jest kolejno przez: sodowy zeolit X, wapniowy zeolit A, a następnie klimoptilolit i modernit. Na podstawie pomiarów w dalekiej podczerwieni wstępnie oznaczono pasma odpowiadające drganiom kationów wymiany oraz atomów w ieci krystalicznej zeolitów.