scholarly journals Influence of mechanochemical activation on dissolving model corrosion films formed on ion-exchange resins using Trilon B

2022 ◽  
Vol 11 (4) ◽  
pp. 663-672
Author(s):  
M. S. Palamarchuk ◽  
D. Kh. Shlyk ◽  
S. Yu. Bratskaya
Keyword(s):  
Ion Exchange ◽  
Oxalic Acid ◽  
Iron Oxides ◽  
Cation Exchanger ◽  
Mechanochemical Activation ◽  
Oxide Surface ◽  
Ion Exchange Resins ◽  
Poorly Soluble ◽  
Activated Corrosion Products ◽  
Exchange Resins

Inorganic deposits formed during operation and intermediate storage contain radionuclides, whose removal during the chemical decontamination of spent ion-exchange resins used in filters for special water purification at nuclear power plants has proved to be a challenge. In such deposits, radionuclides of the corrosion group (58.60Co, 54Mn, 51Cr) are typically located in the crystal lattice of poorly soluble iron oxides. The present work discusses the possibility of using mechanochemical activation in the decontamination of spent ion-exchange resins polluted with deposits of activated corrosion products from structural materials. Samples of natural and synthesised on the surface of the KU-2-8 cation exchanger in the presence of the 57Co label magnetites were used as model deposits. It was shown that an increase in the duration of mechanochemical activation leads to an increase in the dissolution rate of magnetite in model decontamination solutions based on еthylenediaminetetraacetic acid disodium salt (Trilon B) and nitric acid. It was shown that, when using Trilon B, magnetite dissolves more efficiently, which is explained by the interaction between the oxide surface and organic complexing agents. It can be assumed that solid-phase reactions occur during the mechanochemical activation of magnetite in the presence of dry reagents (Trilon B, oxalic, ascorbic and citric acids). Therefore, a poorly soluble shell formed on the oxide surface hinders the dissolution at a low magnetite/solution ratio. Unlike the reagent-free activation, for magnetite activated in the presence of oxalic acid, an increase in the solution/magnetite ratio promotes the dissolution of iron oxides. Using the example of a model cation exchanger, it was shown that the rate and efficiency of decontamination of spent ion-exchange resins polluted with deposits containing activated corrosion products increase significantly after mechanochemical activation in the presence of oxalic acid.

The Interaction of Bituminized Ion-Exchange Resins With Different Leachants

1984 ◽  
Vol 44 ◽  
Author(s):  
M. Valkiainen ◽  
Ulla Vuorinen ◽  
Paula Uotila
Keyword(s):  
Ion Exchange ◽  
Cation Exchanger ◽  
Deionized Water ◽  
Ion Exchange Resins ◽  
Leaching Tests ◽  
Surrounding Water ◽  
Waste Products ◽  
Leach Rate ◽  
Simulated Waste ◽  
Exchange Resins

AbstractLeaching tests on bituminized ion-exchange resins from Olkiluoto power plant were made according to ISO/DIS 6961 in deionized water and groundwater. Simulated waste products including Cs and Sr were leached in cement water. A clear difference is seen between the water types. With cobalt in granular resins the leach rate in groundwater is three orders of magnitude higher than in deionized water, the latter being in the order of 10–15 m/s.The bituminized cation exchanger is still operating and changing ions with the surrounding water. Bitumen provides a hindering diffusion barrier.Bituminized resin absorbs water from the surroundings and the weight (and volume) of the product increases 10–80 % in 898 days compared to the original value. The weight increase is slower with bituminized powdered resins than with granular resins.Due to differencies in densities between bitumen and both anion and cation ion-exchangers, a distinct sedimentation effect of granular mixed bed exchangers is observed. The cation exchanger is separated on the bottom of the 200 1 drum while the anion exchanger is separated in the upper part of the drum.

scholarly journals Catalytic oxidation of cation exchanger KU-2×8 with an aqueous solution of hydrogen peroxide

2019 ◽  
Vol 58 (5) ◽  
pp. 54-61
Author(s):  
Marina M. Kozlova ◽  
◽  
Artem E. Bobylev ◽  
Larisa N. Maskaeva ◽  
Vyacheslav F. Markov ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Ion Exchange ◽  
Sulfonic Acid ◽  
Nuclear Power ◽  
Power Plants ◽  
Nuclear Power Plants ◽  
Cation Exchanger ◽  
Ion Exchange Resins ◽  
Acid Cation ◽  
Exchange Resins

During the operation of nuclear power plants, spent ion-exchange resins are formed, which are heterogeneous radioactive low-level waste in the form of particles from a cross-linked organic polymer. Such resins may not always be regenerated. Therefore, the disposal of spent ion exchange resins is currently one of the primary problems at nuclear power plants. Conventional technologies for the processing of waste resins are relatively expensive. In addition, there are difficulties with transportation and storage of waste, and the disposal of spent ion exchange resins is a complex process. In the present study, an attempt has been made to solve the problem of spent ion-exchange resins utilization on example of the sulfonic acid cation exchanger’s KU-2×8 oxidative degradation with the Fenton reaction. The decomposition of the cation exchanger was carried out with 20% hydrogen peroxide in the temperature range 323-353 K in the presence of a catalyst – low concentration copper(II) sulfate (0.001-0.009 mmol/l). The influence of process temperature and catalyst concentration on the reaction rate was estimated. When determining the rate of the cation exchanger KU-2×8 heterogeneous oxidation reaction with hydrogen peroxide in the presence of a catalytic additive, the spherical shape of the sorbent granules, the surface area of which changed during reaction, was taken into account. It was shown that with a reaction temperature increasing from 323 to 353 K, the rate constant of cation exchanger's oxidative decomposition have increased by a factor of 20-37. The activation energy values of the sulfonic acid cation exchanger's KU-2×8 decomposition with hydrogen peroxide in the presence of copper(II) sulfate are 89.7-115.2 kJ/mol, which indicates that the process is in the kinetic mode. It was established with electron-microscopic studies that the beads of the cation exchanger KU-2×8, when decomposed in H2O2 solution in the presence of a catalyst can stick together, change their shape and volume, and their surface becomes covered with cracks. The studies performed showed almost complete catalytic decomposition of cation exchanger KU-2×8 in a hydrogen peroxide solution at 323-353 K after 420-220 minutes, which allows accelerating the oxidation at relatively low temperatures.

Embedding Procedure for Water Swollen Samples

1970 ◽  
Vol 28 ◽  
pp. 504-505
Author(s):  
Ann M. Thomas ◽  
Virginia Shemeley
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ion Exchange ◽  
Structural Changes ◽  
Cross Linking ◽  
Ion Exchange Resins ◽  
Transmission Electron ◽  
First Pass ◽  
Exchange Resins

Those samples which swell rapidly when exposed to water are, at best, difficult to section for transmission electron microscopy. Some materials literally burst out of the embedding block with the first pass by the knife, and even the most rapid cutting cycle produces sections of limited value. Many ion exchange resins swell in water; some undergo irreversible structural changes when dried. We developed our embedding procedure to handle this type of sample, but it should be applicable to many materials that present similar sectioning difficulties.The purpose of our embedding procedure is to build up a cross-linking network throughout the sample, while it is in a water swollen state. Our procedure was suggested to us by the work of Rosenberg, where he mentioned the formation of a tridimensional structure by the polymerization of the GMA biproduct, triglycol dimethacrylate.

Applications of Ion Exchange Resin in Oral Drug Delivery Systems

2017 ◽  
Vol 7 (03) ◽  
Author(s):  
Kathpalia Harsha ◽  
Das Sukanya
Keyword(s):  
Drug Delivery ◽  
Ion Exchange ◽  
Drug Delivery Systems ◽  
Oral Drug Delivery ◽  
Physical Stability ◽  
Delivery Systems ◽  
Oral Drug ◽  
Ion Exchange Resins ◽  
Exchange Resins ◽  
Oral Drug Delivery Systems

Ion Exchange Resins (IER) are insoluble polymers having styrene divinylbenzene copolymer backbone that contain acidic or basic functional groups and have the ability to exchange counter ions with the surrounding aqueous solutions. From the past many years they have been widely used for purification and softening of water and in chromatographic columns, however recently their use in pharmaceutical industry has gained considerable importance. Due to the physical stability and inert nature of the resins, they can be used as a versatile vehicle to design several modified release dosage forms The ionizable drug is complexed with the resin owing to the property of ion exchange. This resin complex dissociatesin vivo to release the drug. Based on the dissociation strength of the drug from the drug resin complex, various release patterns can be achieved. Many formulation glitches can be circumvented using ion exchange resins such as bitter taste and deliquescence. These resins also aid in enhancing disintegrationand stability of formulation. This review focuses on different types of ion exchange resins, their preparation methods, chemistry, properties, incompatibilities and their application in various oral drug delivery systems as well as highlighting their use as therapeutic agents.

THE DISPOSAL OF USED ION EXCHANGE RESINS

2004 ◽  
Vol 3 (3) ◽  
pp. 447-455
Author(s):  
Viky Dicu ◽  
Carmen Iesan ◽  
Mihai Chirica ◽  
Satish Bapat
Keyword(s):  
Ion Exchange ◽  
Ion Exchange Resins ◽  
Exchange Resins

FTIR ANALYSIS OF ION EXCHANGE RESINS WITH APPLICATION IN PERMANENT HARD WATER SOFTENING

2014 ◽  
Vol 13 (9) ◽  
pp. 2145-2152 ◽  
Author(s):  
Liliana Lazar ◽  
Laura Bulgariu ◽  
Bogdan Bandrabur ◽  
Ramona-Elena Tataru-Farmus ◽  
Mioara Drobota ◽  
...  
Keyword(s):  
Ion Exchange ◽  
Hard Water ◽  
Ion Exchange Resins ◽  
Ftir Analysis ◽  
Water Softening ◽  
Exchange Resins

Innovative and sustainable concept of regeneration of decolorization ion exchange resins

2012 ◽  
pp. 381-384 ◽  
Author(s):  
M.A. Theoleyre ◽  
Anne Gonin ◽  
Dominique Paillat
Keyword(s):  
Ion Exchange ◽  
Water Requirement ◽  
Ion Exchange Resins ◽  
Salt Solutions ◽  
Nanofiltration Membranes ◽  
Industrial Efficiency ◽  
Salt Consumption ◽  
Multiple Effect ◽  
Exchange Resins

Regeneration of resins used for decolorization of sugar solutions is done with concentrated salt solutions. Nanofiltration membranes have been proven effective, in terms of industrial efficiency in decreasing salt consumption. More than 90% of the salt that is necessary for regeneration can be recycled through a combination of direct recycling of intermediate eluates, the separation of colored compounds by use of very selective nanofiltration membranes and a multiple-effect evaporation of salty permeates. The desalted color compound solution is sent to the molasses, limiting considerably the effluent to be treated. Starting from a liquor of 800 IU, the water requirement is limited to less than 100 L/t of sugar and the amount of wastewater can be reduced to less than 40 L/t of sugar.

Innovative concepts of regeneration of decolorization ion exchange resins in sugar refineries

2016 ◽  
pp. 377-380
Author(s):  
Marc André Théoleyre ◽  
Anne Gonin ◽  
Dominique Paillat
Keyword(s):  
Ion Exchange ◽  
Reverse Osmosis ◽  
Energy Supply ◽  
Ion Exchange Resins ◽  
Salt Solutions ◽  
Nanofiltration Membranes ◽  
Local Conditions ◽  
Salt Consumption ◽  
Multiple Effect ◽  
Exchange Resins

Regeneration of resins used for decolorization of sugar solutions is done with concentrated salt solutions. Nanofiltration membranes have been proven effective, in terms of industrial efficiency in decreasing salt consumption. More than 90% of the salt that is necessary for regeneration can be recycled through a combination of direct recycling of intermediate eluates, the separation of colored compounds by use of very selective nanofiltration membranes and a system to concentrate salty permeates. According to specific local conditions on energy supply and cost, the concentration of salty permeates can be either a multiple effect evaporator or a combination of electrodialysis and reverse osmosis. The desalted color compound solution is sent to the molasses, limiting considerably the effluent to be treated. Starting from a liquor of 800 IU, the water requirement is limited to less than 100 L/t of sugar and the amount of wastewater can be reduced to less than 40 L/t of sugar.

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