ВЛИЯНИЕ ПОВЕРХНОСТНОГО МОДИФИЦИРОВАНИЯ ГИДРАТИРОВАННОГО ДИОКСИДА ТИТАНА НА СЕЛЕКТИВНОСТЬ ПО ОТНОШЕНИЮ К СТРОНЦИЮ

The effect exerted on the selectivity of hydrated TiO2 to Sr by surface modification of the sorbent involving immobilization of mixed nickel potassium ferrocyanide was studied. The Sr specificity of the resulting sorbent (denoted as T-55) is comparable with that of hydrated TiO2: logK d (K d is Sr distribution coefficient, ml g-1) is 2.7 ± 0.2 in sorption from tap water with pH 7.8 ± 0.2, 2.7 ± 0.5 in sorption from CaCl2 solutions with pH 5.6 ± 0.2, and from 2.5 ± 0.8 to 1.7 ± 0.4 in sorption from CaCl 2 solutions with pH 7.0 ± 0.2. The modification makes the resulting T-55 sorbent selective to Sr in the presence of Ca at pH 5-6. © 2013 Pleiades Publishing, Ltd

ВЛИЯНИЕ КОНЦЕНТРАЦИИ КАЛИЯ, НАТРИЯ И АММОНИЯ НА СОРБЦИЮ ЦЕЗИЯ СМЕШАННЫМ ФЕРРОЦИАНИДОМ НИКЕЛЯ-КАЛИЯ НА ОСНОВЕ ГИДРАТИРОВАННОГО ДИОКСИДА ТИТАНА

The effect of single-charged cations (Na+, K+, NH 4 +) on the cesium sorption with mixed nickel potassium ferrocyanide sorbent based on hydrated TiO2 was studied. The K + and Na+ ions exert no effect at their concentrations of up to 0.5 M; the Cs+ distribution coefficients from KCl and NaCl solutions are (1.1 ± 0.5) Ч 105 and (8 ± 3) Ч 104 mL g-1, respectively. The sorbent is highly specific to Cs+ in the presence of ammonium ions. The sorption mechanisms were studied. The concentration ranges in which Cs+ and NH 4 + are sorbed by independent mechanisms (Cs+, by the ferrocyanide phase; NH 4 +, by the phase of hydrated TiO2) and in which the Cs+ distribution coefficient decreases owing to competitive filling of the ferrocyanide phase with ammonium ions were determined. At cesium concentrations in solution exceeding 50 mg L-1, Cs+ and NH 4 + are absorbed jointly owing to coprecipitation in the mixed ferrocyanide phase in the pore space of the sorbent. © 2013 Pleiades Publishing, Ltd

Изучение закономерностей синтеза тонкослойных неорганических сорбентов и областей их применения для извлечения радионуклидов из жидких радиоактивных отходов

Объектами исследования являются поверхностно-модифицированные ферроцианидные сорбенты на основе гидратированного диоксида титана. Целью данной работы является изучение закономерностей синтеза поверхностно-модифицированных неорганических сорбентов и способов их применения для переработки жидких радиоактивных отходов и иммобилизации радионуклидов цезия и стронция. В ходе работы был поставлен ряд экспериментов по изучению закономерностей синтеза смешанного ферроцианида никеля-калия на основе гидратированного диоксида титана (сорбент Т-55), исследованы механизмы и закономерности сорбции радионуклидов синтезированным сорбентом в присутствии различных мешающих примесей, возможности иммобилизациии радионуклидов цезия и стронция. На основании полученных экспериментальных данных были сделаны выводы о возможных сферах применения синтезированного сорбента для переработки ЖРО различного состава и для сорбционного концентрирования в методах анализа природных вод и технологических растворов на радионуклиды цезия. По результатам, полученным в данной работе, написано 2 статьи в зарубежные рецензируемые журналы и 4 тезиса докладов на конференции.Программа развития УрФУ на 2013 год (п.2.1.1.1

A technology of drinking water decontamination from radon and its decay products

Underground water is one of the main sources of radon for households. This article focuses on the estimation and removal of radon from underground water using the technology and inorganic sorbents developed by EKSORB Ltd., Russia for liquid radioactive waste treatment in the nuclear power industry. The article presents the results of tests of a system for the removal of radon and radon daughters from water patented by EKSORB. This is achieved by filtering water through RATZIR sorbent, followed by periodic load regeneration. Over a period of three years, the plant is successful in removing radon from the water that had an initial radon content of approximately 1500 Bq/L to less than 60 Bq/L, without releasing radon to indoor/outdoor air. © 2020 Igor Voinov et al., published by Sciendo 2020

Impact of Pollutants of Natural and Anthropogenic Origin on the Quality of Wastewater in Ekaterinburg

The object of the study was river water, which was sampled 500 m before and 500 m after the point of discharge of wastewaters from industrial activities. The concentration of chlorides, magnesium, and calcium in all the studied samples was below the value of the acceptable limit concentration. The pH of the water samples and the sulphate concentration were within acceptable limits. The concentration of iron, ammonium, and nitrite in water samples was higher than the value of acceptable limit. It was suggested that water pollution with iron and nitrite was mainly due to natural processes, and the presence of ammonium and oil products could be explained by anthropogenic sources. © Published under licence by IOP Publishing Ltd.The article was prepared with the financial support of Competitiveness Enhancement Program – CEP 3.1.1.1-20

Development and Approbation of a Method for Analysis of the Uranium Isotopic Ratio of in Technological Solutions at Uranium Mining Enterprises

The article describes the development and approbation of a method for analysis of the isotopic composition of uranium in technological solutions of the uranium mining enterprise and identifies the optimal parameters for each stage of analysis in order to achieve the maximum degree of uranium recovery from productive solutions (PR).В статье описывается разработка и апробация метода анализа изотопного состава урана в технологических растворах урандобывающего предприятия и определяются оптимальные параметры для каждой стадии анализа с целью достижения максимальной степени извлечения урана из продуктивных растворов (ПР)

STUDY OF RADIUM-223 SORPTION BY THIN-LAYER SORBENTS BASED ON MANGANESE DIOXIDE ON VARIOUS POLYMER SUPPORTS

The work is devoted to the study of radium-223 sorption by thin-layer sorbents based on manganese dioxide on various polymer supports. The effect of salt content and solid/liquid ratio was evaluated. Comparison of sorption properties of various polymer supports was per-formed.Исследование выполнено при финансовой поддержке РФФИ в рамках научного проекта № 20-03-00931

Изучение закономерностей осаждения тонких сорбционно-активных пленок диоксида марганца на различных полимерных носителях

Manganese dioxide (MnO2) is used as a sorption material for the isolation of a wide range of substances from aqueous media. A number of composite materials containing MnO2 are known, while in the scientific literature there are no systematic data on the possibilities of obtaining flat thin-layer sorbents of manganese dioxide on other polymer carriers. In this study, a number of flat thin-layer sorbents, consisting of manganese dioxide deposited on the surface of various carriers, were synthesized. The most common flat materials were used as carriers - polyethylene (PE), polypropylene (PP), biaxially oriented polypropylene film (BOPF), polyethylene terephthalate (PET), cellulose triacetate (CTA). The films were kept in an acidic solution of potassium permanganate, washed, and the manganese content was determined. It was shown that according to the rate of deposition of manganese dioxide on the surface of the carrier, these materials are arranged in a row: CTA >> PE> BOPF> PET ≈ PP. It was found that the dependences of the specific content of manganese dioxide on the surface of polymer carriers were well approximated by straight lines (R2 = 0.964 - 0.997); the results of linear processing of the dependences were used to determine the deposition rates of manganese dioxide, ranging from 1.55 ± 0.26 μg/(cm2 day) for PP up to 166 ± 11 μg/(cm2 day) for CTA. It was shown that the high rate of deposition of manganese dioxide on the surface of the CTA in comparison with other polymer carriers was most likely due to the macroporous texture of the CTA surface. It was also shown that with a specific content of manganese dioxide of the order of 150-300 μg/cm2 achieved after 1-2 days of CTA treatment in a permanganate solution, a continuous uniform sorption-active layer was formed, and with a longer exposure time, an increase in the average layer thickness occurred due to the growth of individual crystallites already on the surface of a continuous layer of manganese dioxide, leading to a significant heterogeneity of the sorption-active surface, as well as to a stable deformation of the film. The sorption of 223Ra was studied on a series of obtained sorbents. It was shown that the amount of manganese dioxide phase in the composition of thin-layer sorbents had practically no effect on the sorption of radium from a salt-free solution, but strongly influenced sorption from 0.5 M NaCl. Also, for the MnO2-CTA sorbent the deterioration of the quality of the alpha spectrum due to the diffusion of radium deep into the sorbent was demonstrated. © 2021 Semenishchev V.S., Oglezneva V.Yu., Titova S.M.,Malyshev A.S., Filinkova V.K.Исследование выполнено при финансовой поддержке РФФИ в рамках научного проекта № 20-03-00931