We report on the design and performance of composite sorbents based on 4',4”(5”)-di-tert-butyldicyclohexano-18-crown-6 and novel fluorinated diluents for the selective separation and pre-concentration of 210Pb and 210Po. The sorbents were synthesized by impregnation of a solid support with solutions of the crown ether in three fluorinated diluents: 3-nitrobenzotrifluoride (F-3), bis(2,2,3,3-tetrafluoropropyl) carbonate (BK-1), and bis(2,2,3,3-tetrafluoropropoxy)-methane (FN-1). The synthesis was optimized with respect to the choice of support, solvent, and key conditions—namely, impregnation temperature and time, as well as crown ether concentration. Optimal performance was achieved using a styrene–divinylbenzene support (LPS-500, 50–60 μm) impregnated with 1 mol L–1 crown ether solution in the diluent, using chloroform as a solvent which was subsequently removed. The materials were comprehensively characterized by IR spectroscopy, XPS, SEM, and EDS. These analyses confirmed the successful incorporation of active components into the support. Among the studied diluents, BK-1 provided the highest lead distribution coefficients, reaching up to (8.6 ± 0.6)·103 mL g–1. Efficient recovery of 210Pb and 210Po from 1 mol L–1 HNO3 was achieved with distribution coefficients values up to 7.05·103 and 2.93·103 mL g–1, respectively, and quantitative desorption was accomplished using 5–6 mol L–1 HCl. This combination of high distribution coefficients, pronounced selectivity in acidic media, and facile regeneration using HCl solutions demonstrates the potential of these novel composites for practical application in the separation and preconcentration of lead, including radionuclides 210Pb and 210Po, from complex matrices.

A new method for extraction kinetics studying in a biphasic system using time-lapse recording of IR absorption spectra in the attenuated total internal reflection (ATR IR) geometry is developed. The method is examined by studying the extraction process of europium, yttrium and cesium ions with various extractants both from acidic and carbonate media. The mechanism of step-wise coordination with functional groups of the ligand is proposed. The extraction kinetics constants are calculated for the extraction systems with europium. The main advantages of the new method are miniaturization and rapidity, compared to classical methods.

The article presents the results of studies on composition optimization, properties, and laboratory dynamic tests of extraction mixtures based on p-isononylcalix[6]arene for the alkaline HLW purification to remove 137Cs. The distribution of 137Cs among the products of the technological scheme is presented and the coefficients of raffinate purification to remove 137Cs are determined. It was revealed that, in the case of using nitric acid as a stripping solution, nitrosation of p-isononylcalix[6]arene is possible in the technological process. The composition of the resulting product was determined. To prevent nitrosation of p-isononylcalix[6]arene, formic acid was used in the stripping stage, which ensured stable operation of the extraction stand for 48 h with 137Cs extraction from model alkaline HLW at a level of 99.7%.

A new method of yttrium recovery with a mixture of hydroxyaromatic compound (8-hydroxyquinoline, 2,3-dihydroxynaphthalene) and methyltrioctylammonium carbonate separation from strontium in carbonate media has been proposed. Yttrium extraction from carbonate media has been studied. The structures of yttrium solvates with ligands formed during extraction have been proposed. The suggested method for yttrium recovery from soil by sample calcination followed by carbonate leaching and extraction with the specified mixture allows the efficient separation of yttrium-strontium pair and yttrium recovery.

New promising extraction systems based on crown ethers and polyfluorinated diluents were studied as applied to competing extraction of components of simulated high-level waste (HLW). The suggested method allows joint recovery of trace amounts of all the metals studied, followed by direct ICP-MS analysis of the equilibrium aqueous and organic phases, skipping the stripping step. A comparative analysis of the distribution ratios determined by the radiometric and indirect methods was performed. The direct procedure allows the accuracy of the results obtained to be improved by more than 10

Extraction systems based on extraction of tetrafluoroboric acid (HBF 4 ) with tributyl phosphate (TBP) and triamylphosphine oxide (TAPO) for boron isotope separation were studied. Tetrafluoroboric acid was studied in comparison with boric acid (H 3 BO 3 ). The extraction isotherms at 20°C for four systems (boric and tetrafluoroboric acids extracted with TBP and TAPO in o -xylene) were obtained, and single-stage isotope separation factors for these four systems were determined. The lighter boron isotope ( 10 B) is concentrated in the aqueous phase in the systems containing tetrafluoroboric acid, whereas in the systems with boric acid it is concentrated in the organic phase.

Изучена жидкостная экстракция пары 90 Y/ 90 Sr из карбонатных сред смесями ароматических дигидроксисоединений и четвертичной аммониевой соли - карбоната метилтриоктиламмония (МТОАК) - в толуоле и бутилацетате. Установлено, что МТОАК повышает коэффициенты распределения и самого экстрагента, и его сольвата с иттрием за счет образования смешанного комплекса иттрия и дигидроксиароматического лиганда с МТОАК. При экстракции из щелочно-карбонатных сред в интервале рН 12-13.5 смесями 0.01 M 2,3-дигидроксинафталина и 0.015 M MTOAК в бутилацетате или толуоле коэффициенты распределения иттрия превышают 80; коэффициенты разделения пары 90 Y/ 90 Sr в этих условиях более 10 5 . Для полной реэкстракции иттрия могут быть использованы разбавленные растворы соляной, азотной и серной кислот. Изученные смеси химически устойчивы и не изменяют экстракционных свойств при многократном повторении циклов экстракции-реэкстракции. Модельные эксперименты по выщелачиванию иттрия из природных образцов показали, что процент извлечения стабильного иттрия из песка составляет 70-80%, в то время как процент извлечения иттрия из почвы - 50-60%.

A new type of potentiometric sensor for cesium ions based on a crown ether (dibenzo-21-crown-7) is proposed; its analytical characteristics are presented: limit of detection, slope of electrode function, selectivity to a number of interfering ions, and the working pH range of solutions.

The solvent extraction of the 90Y/90Sr pair from carbonate media with mixtures of aromatic dihydroxy compounds and a quaternary ammonium salt—methyltrioctylammonium carbonate (MTOAC)—in toluene and butyl acetate was studied. It was found that MTOAC increases the distribution coefficients of both the extractant itself and its solvate with yttrium due to the formation of a mixed complex of yttrium and a dihydroxyaromatic ligand with MTOAC. During extraction from alkaline carbonate media in the pH range of 12–13.5 with mixtures of 0.01 M 2,3-dihydroxynaphthalene and 0.015 M MTOAC in butyl acetate or toluene, the distribution coefficients of yttrium exceed 80; the separation factors of the 90Y/90Sr pair under these conditions are more than 105. Dilute solutions of hydrochloric, nitric, and sulfuric acids can be used for the complete stripping of yttrium. The studied mixtures are chemically stable and do not change the extraction properties upon multiple extraction/stripping cycles. Model experiments on the leaching of yttrium from natural samples showed that the percentage of stable yttrium extraction from sand is 70–80

Strontium-selective potentiometric sensors with polymeric membranes based on di-tert-butyldicyclohexano-18-crown-6 were developed to control the strontium content in technological solutions of radiochemical industries. The detection limit is shown to be 2 × 10–6 M, and the slope of the electrode function is 29 ± 1 mV/pSr. The selectivity coefficients of the strontium-selective sensor towards the main interfering ions were determined. It was established that the dose of ionizing radiation at the 10 kGy level does not significantly affect the performance of the developed strontium-selective sensors.

Разработаны стронций-селективные потенциометрические сенсоры с полимерными мембранами на основе ди- трет -бутилдициклогексано-18-краун-6 для контроля содержания стронция в технологических растворах радиохимических производств. Показано, что предел обнаружения составляет 2 × 10 -6 М, а крутизна электродной функции 29 ± 1 мВ/pSr. Определены коэффициенты селективности стронций-селективного сенсора по отношению к основным мешающим ионам. Установлено, что доза ионизирующего облучения на уровне 10 кГр существенно не влияет на рабочие характеристики разработанных стронций-селективных сенсоров.

A procedure for studying the extraction kinetics of components of long-lived spent nuclear fuel and high-level waste by recording the IR absorption spectra in the attenuated total reflection geometry was developed. The procedure was applied to the extraction of Eu(NO 3 ) 3 with triamylphosphine oxide (TAPO) and octyl(phenyl)- N , N -diisobutylcarbamoylmethylphosphine oxide (CMPO). The extraction rate constant was calculated for the system with TAPO. A mechanism of the interaction of CMPO with Eu 3+ ions was suggested.

The extraction ability and selectivity of nonmacrocyclic (8-quinolinol and 2,3-dihydroxynaphthelene) and macrocyclic (sulfur-containing calixarene derivatives) ligands toward rare earth and transplutonium elements in carbonate media was studied. Both macrocyclic and nonmacrocyclic derivatives showed moderate selectivity to americium in the Am/Eu pair (separation factor SF from 1.6 to 14 at pH > 12), and sulfur-containing calixarenes showed also high selectivity to Am in the Am/Cm pair (SF 3–8 at pH > 13). The compounds studied show promise as extractants for group recovery and separation of actinides, and also for separation of rare earth and transplutonium elements in carbonate media.

The possibilities of 90Y/90Sr separation from carbonate media are investigated as a green alternative method. Solvent extraction of yttrium and strontium from carbonate solution is studied using several extractants in different organic diluents. 8-hydroxyquinioline and 2,3-dihydroxynaphtalene possess a promising Y/Sr separation. Yttrium and strontium distribution ratios D and separation factors SF are evaluated. pH interval 13 13.5 is regarded as the optimum for separation. Yttrium is extracted much better in 2-nitrotoluene (DY=3.9), maximum separation is observed in 2-nitrotoluene SF = 195 at pH 13.5.

Several extraction systems based on functionalized calixarenes in mixed fluorinated diluents were examined. Technological flowsheets for radioactive waste processing with these extraction systems were developed and tested. It is shown that under the selected conditions one can achieve decontamination factors from cesium isotopes and alpha-emitters, sufficient for converting high-level waste of the “Mayak” Production Association into the low-level category with the subsequent possibility of their disposal at near-surface sites.

The study of the interphase distribution of a large number of target and impurity components of highly radioactive wastes is a necessary and very laborious stage in the creation of new extraction systems. With the quantitative extraction of cesium-137 and strontium-90 from spent nuclear fuel for the purposes of further industrial and commercial use, difficulties arise associated with competing complexation and the concomitant extraction of impurities of stable elements. We have developed an express method for determining the distribution ratios of metals using inductively coupled plasma mass spectrometry (ICP-MS). A feature of the proposed method is the joint extraction of trace amounts of all studied metals, followed by direct ICP-MS analysis of equilibrium aqueous and organic phases.

We observed positive results of MRET water complimentary treatment for HIV patients during a clinical trial. There are recent research data which allows pointing to a similar mode of action for the two viral proteins, suggesting that anti-viral strategy that targets the viral-induced membrane fusion step can be adapted from HIV-1 to SARS-CoV. The stability of virus spike protein structure is based on the overall interactions of vander Walls weak electrodynamic forces and hydrogen bonding. It is obvious, that all biochemical formations of proteins require presence of water molecules in biological systems. The overall observed research data suggest that modification of water – based medium electrodynamic parameters of the human tissues (that are favourable for the homeostasis of the body in the range of physiological “window”) can lead to significant change of van der Walls interactions and hydrogen bonding that may result in the inhibition and interruption of virus spike proteins formation. Such scenario obviously disables virus life sequence of attachment and fusion with human cell membranes. The same type of mechanism can be adopted for the inhibition of other lines of pathogenic microorganisms. The studies conducted at AltheaDx Technology; USA confirm that MRET activated water-based medium did not affect the morphology of normal PBMC cells on genetic level; it affected the morphology of normal PBMC cells in a positive way increasing their viability. MRET Activated Water is produced with the help of patented in the USA Molecular Resonance Effect Technology (MRET, US Patent # 6022479). We suggest that MRET water consumption by human subjects can lead to physiologically favourable modification of dielectric permittivity and hydrogen bonding of water –based medium in the human body tissues. It can provide the initial human body natural defence against intervention and spread of pathogenic microorganisms. Keywords: coron virus, MRET water, dielectric permittivity, protein spike.

The effect of γ-radiation on the extraction properties of two functionalized calixarenes (p-tert-butyl-thiacalix[4]arene and p-tert-butylcalix[8]arene) is studied. The most characteristic products of the irradiated extractants interaction with diluent are identified by mass spectrometry. Extraction ability of studied calixarenes towards cesium and americium before and after irradiation is evaluated. Quantitative analysis of chloride and sulfate ions after irradiation is performed to estimate the radiological degradation degree of components. Irradiation has different effect on p-tert-butyl-thiacalix[4]arene and p-tert-butylcalix[8]arene extraction ability towards americium, which may be due to the nature and extraction ability of radiolysis products, and practically does not affect cesium extraction.