Exchanges of strontium on clinoptilolite zeolite

Download
2003
Gül, Özkan
Sr-90 and Cs-137, nuclear fission products, are the major sources of medium-level radioactive waste which must be decontaminated. Inorganic ion exchangers are the preferred materials to eliminate radioisotopes from aqueous nuclear waste because of their high selectivity, radiation and thermal stability, low cost and likely compatibility with cement containment. Clinoptilolite and other zeolites are widely used in nuclear industry for the removal of radioisotopes from aqueous nuclear waste. In this study, the performance of local clinoptilolite zeolite from Gördes region has been investigated so as to determine the conditions under which it can be used effectively in the column for strontium and cesium removal. It was found that under different loading conditions, breakthrough capacity varied from 0 to 0.4078 meq/g for strontium removal, breakthrough capacity varied from 0.1178 to 0.7800 meq/g for cesium removal. It was also determined that the increase of the flow rate reduced the exchange capacity of the bed. Effect of cationic form of the zeolite (Na-CLI: Sodium form of clinoptilolite and Original-CLI: Original form of clinoptilolite) on the breakthrough capacity was also searched. It was observed that Na-CLI performed much better for the removal of strontium and cesium with respect to its original form. In addition, effect of presence of calcium in the feed solution on the breakthrough capacity was investigated and it was found that presence of calcium in the feed solution makes strontium removal essentially impossible, in the case of cesium, presence of calcium in the feed solution decreases breakthrough capacity significantly.

Suggestions

Axial gas mixing in conical spouted beds with high density particles
Güler, Neslin; KÖKSAL, MURAT; Külah, Görkem (2023-10-01)
Conical spouted beds operating with high-density particles (ρp > 2500 kg/m3) have recently gained attention because of their potential use as nuclear fuel coaters for next-generation nuclear reactors. In the literature, the number of axial gas mixing studies in conical and conical-cylindrical spouted beds is very limited and all axial mixing studies were carried out with relatively light particles (ρp ≤ 2500 kg/m3). Therefore, the objective of this study was to generate experimental data that can be used to...
Use of poly(methyl methacrylate) in radioactive waste management: II. Monte Carlo simulations
Ozdemir, Tonguc; Usanmaz, Ali (Elsevier BV, 2009-11-01)
Radioactive waste is generated from the nuclear applications and it should properly be managed in a radioactive waste management system. Different methods are available for treatment and conditioning of radioactive waste. Polymers can be used in the radioactive waste management as an embedding matrix. Poly(methyl methacrylate (PMMA) is a possible candidate material that can be used in the low level radioactive waste management. In this study, based on total resistible dose for PMMA, maximum waste activity t...
Investigation Of Influencing Factors For Biological Hydrogen Production By R. Capsulatus In Tubular Photo-Bioreactors
Boran, E.; Ozgur, E.; Gebicki, J.; van der Burg, J.; YÜCEL, MUSTAFA; Gündüz, Ufuk; Modigel, M.; Eroglu, I. (2009-05-13)
Biological hydrogen production processes are considered as an environmentally friendly way to produce hydrogen. They offer the chance to produce hydrogen from renewable energy sources, like sunlight and biomass. This study aims the process development for a photo-fermentative hydrogen production by photosynthetic purple-non-sulfur bacteria, Rhodobacter capsulatus, in a large scale (80L) tubular photo-bioreactor, in outdoor conditions, using acetate as carbon source. It was shown that Rhodobacter capsulatus ...
Activities of copper oxide and Cu-V and Cu-Mo mixed oxides for H2S removal in the presence and absence of hydrogen and predictions of a deactivation model
Yasyerli, S; Dogu, G; Ar, I; Doğu, Timur (2001-11-14)
Considering the importance of high-temperature removal of H2S from industrial gases, sorption studies were carried out on copper oxide and Cu-V and Cu-Mo mixed oxides in the absence and presence of hydrogen in a fixed-bed reactor. Experiments were carried out in a wide temperature range between 300 and 700 degreesC. A significant amount of SO2 was produced with CuO sorbent in the absence of hydrogen. In the case of mixed oxide sorbents, SO2 formation was detected even in the presence of hydrogen. On the bas...
Removal of hydrogen sulfide by clinoptilolite in a fixed bed adsorber
Yasyerli, S; Ar, I; Dogu, G; Doğu, Timur (2002-11-01)
Due to its toxic and corrosive nature, H2S should be safely removed from the gases produced in gasification or combustion processes. In this study, adsorption of hydrogen sulfide was investigated on a natural zeolite, namely clinoptilolite. H2S adsorption characteristics of Western Anatolian clinoptilolite was studied in a fixed-bed system at different temperatures between 100 and 600 degreesC at atmospheric pressure. H2S adsorption capacity of clinoptilolite was found to be about 0.03 g S/g clinoptilolite ...
Citation Formats
Ö. Gül, “Exchanges of strontium on clinoptilolite zeolite,” M.S. - Master of Science, Middle East Technical University, 2003.