scholarly journals Radionuclide 106Ru behavior in aqueous solutions by ion exchange, ultrafiltration, and centrifugation methods

2021 ◽  
Vol 57 (3) ◽  
pp. 331-339
Author(s):  
O. B. Korenkova ◽  
A. V. Radkevich ◽  
N. I. Voronik
Keyword(s):  
Ion Exchange ◽  
Aqueous Solutions ◽  
Waste Treatment ◽  
Membrane Separation ◽  
Liquid Radioactive Waste ◽  
Ionic Species ◽  
Species Formation ◽  
Wide Ph Range ◽  
Ph Range ◽  
Ru Species

The paper presents the results of 106Ru radionuclide behavior regularities study in aqueous solutions in a wide pH range by ultrafiltration, ion exchange and centrifugation methods. The regions of 106Ru various species existence in solution have been established: cationic 106Ru species at pH < 3.5; the transition region of non-ionic species formation in the range of pH 3.5–4.2 and the region of non-ionic species predominant formation at pH > 4.2. A characteristic feature of the studied solutions is the formation of non-ionic particles by microconcentrations of 106Ru via pseudocolloids at lower pH values as compared to ruthenium solutions with a concentration of 10-6–10-4 mol/dm3. The established regularities of the behavior of ruthenium radionuclides can be utilized to increase the efficiency of ion exchange and membrane separation methods at nuclear and radiation facilities for technological solutions and liquid radioactive waste treatment.

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

2009 ◽  
Vol 6 (3) ◽  
pp. 639-650 ◽  
Author(s):  
M. V. Tarase ◽  
W. B. Gurnule ◽  
A. B. Zade
Keyword(s):  
Hydrochloric Acid ◽  
Ion Exchange ◽  
Metal Ions ◽  
Metal Ion ◽  
Polymer Sample ◽  
Equilibrium Method ◽  
Wide Ph Range ◽  
Ph Range ◽  
Exchange Properties

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+2and Pb+2ions. 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+2and Co+2ions than for Cu+2, Hg+2, Zn+2, Ni+2and Pb+2ions.

Utilization of cross-linked chitosan/bentonite composite in the removal of methyl orange from aqueous solution

2014 ◽  
Vol 71 (2) ◽  
pp. 174-182 ◽  
Author(s):  
Ruihua Huang ◽  
Qian Liu ◽  
Lujie Zhang ◽  
Bingchao Yang
Keyword(s):  
Methyl Orange ◽  
Aqueous Solutions ◽  
Ph Value ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Wide Ph Range ◽  
Order Kinetic Model ◽  
Langmuir Isotherm Model ◽  
Ph Range ◽  
A Minor

A kind of biocomposite was prepared by the intercalation of chitosan in bentonite and the cross-linking reaction of chitosan with glutaraldehyde, which was referred to as cross-linked chitosan/bentonite (CCS/BT) composite. Adsorptive removal of methyl orange (MO) from aqueous solutions was investigated by batch method. The adsorption of MO onto CCS/BT composite was affected by the ratio of chitosan to BT and contact time. pH value had only a minor impact on MO adsorption in a wide pH range. Adsorption kinetics was mainly controlled by the pseudo-second-order kinetic model. The adsorption of MO onto CCS/BT composite followed the Langmuir isotherm model, and the maximum adsorption capacity of CCS/BT composite calculated by the Langmuir model was 224.8 mg/g. Experimental results indicated that this adsorbent had a potential for the removal of MO from aqueous solutions.

Amidoxime-functionalized hydrothermal carbon materials for uranium removal from aqueous solution

RSC Advances ◽  
2016 ◽  
Vol 6 (104) ◽  
pp. 102462-102471 ◽  
Author(s):  
Zhibin Zhang ◽  
Zhimin Dong ◽  
Ying Dai ◽  
Saijin Xiao ◽  
Xiaohong Cao ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
High Selectivity ◽  
Carbon Materials ◽  
Uranium Removal ◽  
Wide Ph Range ◽  
Ph Range

Amidoxime-functionalized hydrothermal carbon (AO-HTC) has been synthesized and applied to adsorb U(vi) from aqueous solutions, exhibiting a high selectivity above 60% for a wide pH range from 1.0 to 5.0.

Low-Level Liquid Waste Treatment System Technical Design in China

2013 ◽  
Author(s):  
Juan Zhao
Keyword(s):  
Ion Exchange ◽  
Radioactive Waste ◽  
Waste Treatment ◽  
Fuel Cycle ◽  
Liquid Radioactive Waste ◽  
Liquid Waste ◽  
Spent Fuel ◽  
Nuclear Facilities ◽  
High Concentration ◽  
Low Level

Radioactive wastes are produced within the nuclear fuel cycle operations (uranium conversion and enrichment, fuel fabrication and spent fuel reprocessing). Evaporation is a proven method for the treatment of liquid radioactive waste providing both good decontamination and high concentration. Two technical designs of nuclear facilities for low-level liquid radioactive waste treatment are presented in the paper and the evaluation of both methods, as well. One method is two-stage evaporation, widely used in the People’s Republic of China’s nuclear facilities; another is two evaporator units and subsequently ion exchange, which is based on the experience gained from TIANWAN nuclear power plant. Primary evaporation and ion exchange ensure the treated waste water discharged to environment by controlling the condensate radioactivity, and secondary evaporation is to control concentrates in a limited salt concentration.

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

2009 ◽  
Vol 6 (3) ◽  
pp. 835-843 ◽  
Author(s):  
Sanjiokumar S. Rahangdale ◽  
Anil B. Zade ◽  
Wasudeo B. Gurnule
Keyword(s):  
Hydrochloric Acid ◽  
Ion Exchange ◽  
Metal Ion ◽  
Spectral Studies ◽  
Molar Ratios ◽  
Wide Ph Range ◽  
Metal Ion Uptake ◽  
Uv Visible ◽  
Ph Range ◽  
Exchange Properties

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.

scholarly journals Kinetik und Mechanismus der Substitutionsreaktionen von Komplexverbindungen, XLVIII / Kinetics and Mechanism of the Substitution Reactions of Complexes, XLVIII

1975 ◽  
Vol 30 (5-6) ◽  
pp. 393-398 ◽  
Author(s):  
J. Zsakó ◽  
Cs. Várhelyi ◽  
Z. Finta ◽  
J. Kiss-Jakab
Keyword(s):  
Activation Energy ◽  
Aqueous Solutions ◽  
Kinetic Parameters ◽  
Rate Constants ◽  
Equilibrium Constants ◽  
Ionic Species ◽  
Protolytic Equilibrium ◽  
Substitution Reactions ◽  
Basic Solutions ◽  
Ph Range

In aqueous solutions the nonelectrolyte [Co(DH)2(NO2)(H2O)] participates in protolytic eqilibria and thus it exists in 7 different forms. Rate constants of the aquation, which leads to the substitution of the nitro group, have been measured in the pH-range between 3.72 and 8 at various temperatures. From these data rate constants, activation energies and entropy values of the aquation of 2 ionic species have been derived, as well as equilibrium constants for the protolytic equilibrium between these species. The kinetic parameters obtained have been compared to those of the aquation of the ionic species which exist in acid and basic solutions and the correlation between structure and activation energy of the aquation has been discussed.

scholarly journals Photolysis of sulfosalicylic acid in aqueous solutions over a wide pH range

2006 ◽  
Vol 181 (1) ◽  
pp. 37-43 ◽  
Author(s):  
Ivan P. Pozdnyakov ◽  
Victor F. Plyusnin ◽  
Vjacheslav P. Grivin ◽  
Dmitry Yu. Vorobyev ◽  
Nikolai M. Bazhin ◽  
...  
Keyword(s):  
Aqueous Solutions ◽  
Sulfosalicylic Acid ◽  
Wide Ph Range ◽  
Ph Range

scholarly journals Montmorillonite of the Ohlanlynske deposit and magnetic composites based on it — sorbents for water purification from 137Cs and 90Sr

2021 ◽  
Vol 20 ◽  
pp. 73-80
Author(s):  
S. O. Kobets ◽  
Keyword(s):  
Water Purification ◽  
Natural Waters ◽  
Liquid Radioactive Waste ◽  
Aqueous Media ◽  
Langmuir Equation ◽  
Magnetic Composites ◽  
Natural Minerals ◽  
Magnetic Sorbents ◽  
Wide Ph Range ◽  
Ph Range

A comparative study on the extraction of 137Cs and 90Sr from aqueous media using magnetic composites obtained on the basis of bentonite from the Ohlanlynske deposit and magnetite was carried out. It is shown that magnetic composites based on a natural mineral — bentonite rock, isolated montmorillonite in the Na-form, impurities — clinoptilolite and cristobalite, as well as natural minerals without magnetite, efficiently sorb 137Cs and 90Sr in a wide pH range (3.7–9). Despite the fact that magnetite in the composition of composites practically does not affect the efficiency of purification of aqueous media, but acts as only a magnetoactive component, composites are quite promising sorbents for purifying of large volumes of radioactively contaminated waters due to the possibility of removing water purification sludge using an external magnetic field. It has been established that the highest sorption properties are possessed by magnetic sorbents obtained on the basis of clinoptilolite — for 137Cs, and the Na-form of montmorillonite — for 90Sr. The values of their limiting adsorption by the indicated composites, calculated using the Langmuir equation, are 43.3 and 40.6 mg/g, respectively. It is shown that among the macrocomponents (Na+ , K+ , Ca2+), Ca2+ ions have the greatest influence on the efficiency of purification of natural waters and liquid radioactive waste containing 137Cs and 90Sr radionuclides.

scholarly journals EPR study of the production of oh radicals in aqueous solutions of uranium irradiated by ultraviolet light

2009 ◽  
Vol 74 (6) ◽  
pp. 651-661 ◽  
Author(s):  
Marko Dakovic ◽  
Milos Mojovic ◽  
Goran Bacic
Keyword(s):  
Aqueous Solutions ◽  
Hydroxyl Radicals ◽  
Fluorescence Decay ◽  
Uranyl Acetate ◽  
Oh Radicals ◽  
Solution Ph ◽  
Trapping Method ◽  
Wide Ph Range ◽  
Ph Range ◽  
Epr Spin Trapping

The aim of the study was to establish whether hydroxyl radicals (?OH) were produced in UV-irradiated aqueous solutions of uranyl salts. The production of ?OH was studied in uranyl acetate and nitrate solutions by an EPR spin trap method over a wide pH range, with variation of the uranium concentrations. The production of ?OH in uranyl solutions irradiated with UV was unequivocally demonstrated for the first time using the EPR spin-trapping method. The production of ?OH can be connected to speciation of uranium species in aqueous solutions, showing a complex dependence on the solution pH. When compared with the results of radiative de-excitation of excited uranyl (+22*UO ) by the quenching of its fluorescence, the present results indicate that the generation of hydroxyl radicals plays a major role in the fluorescence decay of + 22 *UO . The role of the presence of carbonates and counter ions pertinent to environmental conditions in biological systems on the production of hydroxyl radicals was also assessed in an attempt to reveal the mechanism of +22*UO de-excitation. Various mechanisms, including ?OH production, are inferred but the main point is that the generation of ?OH in uranium containing solutions must be considered when assessing uranium toxicity.

Coefficient d'activité de l'acide sulfurique déterminé par titrage infrarouge

2000 ◽  
Vol 78 (8) ◽  
pp. 1128-1142 ◽  
Author(s):  
Christophe Ménichelli ◽  
Jean-Joseph Max ◽  
Camille Chapados
Keyword(s):  
Factor Analysis ◽  
Ir Spectroscopy ◽  
Aqueous Solutions ◽  
Activity Coefficients ◽  
Total Concentration ◽  
Relative Concentration ◽  
Ionic Species ◽  
Attenuated Total Reflection ◽  
Equilibrium Equations ◽  
Ph Range

The titration of sulphuric acid by infrared spectroscopy using the attenuated total reflection (ATR) technique was made in the 0 to 14 pH range for solutions ranging from 1.89 to 0.01 M. The subtraction of the water spectrum was made using acidic, neutral, and basic waters which exhibit different spectra. The results gave the spectra of mixtures of the HSO–4 and SO2–4 ionic species in solutions. For each concentration, factor analysis (FA) sorted the spectra of the pure ionic species and gave through the multiplying factors (MF) the distribution of the species as a function of pH. This distribution is the same as that obtained from the equilibrium equations. The IR measurements gave directly the ratios of the activity coefficients of HSO–4 and SO2–4 ions. This ratio varies with the total concentration of both ions but is independent of the relative concentration. The fitting of the experimental and theoretical volumetric titration curves in the high and low pH regions gave the mean activity coefficients of the other species present in the solutions. The values obtained are comparable to those obtained by electrochemical measurements. These results show that it is possible to use IR spectroscopy to study aqueous solutions of inorganic acids from low to high concentrations.Key words : IR spectroscopy, sulfuric acid, aqueous solutions, factor analysis, ATR, principal spectra, solvation, activity coefficients, IR titration.

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