Персона: Вальков, Александр Васильевич
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Институт общей профессиональной подготовки (ИОПП)
Миссией Института является:
фундаментальная базовая подготовка студентов, необходимая для получения качественного образования на уровне требований международных стандартов;
удовлетворение потребностей обучающихся в интеллектуальном, культурном, нравственном развитии и приобретении ими профессиональных знаний; формирование у студентов мотивации и умения учиться; профессиональная ориентация школьников и студентов в избранной области знаний, формирование способностей и навыков профессионального самоопределения и профессионального саморазвития.
Основными целями и задачами Института являются:
обеспечение высококачественной (фундаментальной) базовой подготовки студентов бакалавриата и специалитета; поддержка и развитие у студентов стремления к осознанному продолжению обучения в институтах (САЕ и др.) и на факультетах Университета; обеспечение преемственности образовательных программ общего среднего и высшего образования; обеспечение высокого качества довузовской подготовки учащихся Предуниверситария и школ-партнеров НИЯУ МИФИ за счет интеграции основного и дополнительного образования;
учебно-методическое руководство общеобразовательными кафедрами Института, осуществляющими подготовку бакалавров и специалистов по социо-гуманитарным, общепрофессиональным и естественнонаучным дисциплинам, обеспечение единства требований к базовой подготовке студентов в рамках крупных научно-образовательных направлений (областей знаний).
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Александр Васильевич
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- ПубликацияТолько метаданныеCost-effective separation of rare earth concentrates(2020) Valkov, A. V.; Вальков, Александр Васильевич© 2020, "Ore and Metals" Publishing house. All rights reserved.The rare earth metals (REMs) found in apatite, loparite and the concentrates from the Tomtor deposit may lay the basis for expanding the Russian rare earths industry. The most sellable REMs with an almost unlimited demand include neodymium, praseodymium, dysprosium and terbium. They account for ~80% of the extracted individual REMs sold. It is proposed to design a processing sequence enabling to extract the above elements at minimal cost reaching maximum purity. The rest of the REMs are considered a poorly sellable product. A sequence is proposed to separate REM concentrates recovered from loparite, apatite or the concentrate from the Tomtor deposit, which involves separation of praseodymium mixed with neodymium (didymium) and terbium mixed with dysprosium (dysterbium) with the concentration of the base material being 99.95–99.99 wt%. It was decided to use the system of 100% tributyl phosphate – Ln(NO3)3 – Са(NO3)2 — to separate didymium, and the organophosphorus acid (OPA) based system: i. e. 30% OPA – Ln(NO3)3 – HNO3-to separate dysterbium. The author examined how the centrifugal coefficient, the pure component extraction ratio and the purity of extracted elements determine the required number of stages. The process consists of four extraction cascades. Separation at the praseodymium–cerium boundary is performed without pre-separation of cerium. To separate dysterbium, they separate holmium and heavier REMs in one cascade, and gadolinium and lighter REMs – in the second cascade. The following products are obtained as a result of separation: lanthanum-cerium concentrate, didymium, dysterbium, samarium-europium-gadolinium concentrate and a concentrate of yttrium REMs from holmium to lutecium.
- ПубликацияТолько метаданныеSeparation of Samarium, Europium, and Gadolinium by Extraction with Organophosphorus Acids(2021) Val'kov, A. V.; Igumnov, S. N.; Ovchinnikov, K. V.; Вальков, Александр ВасильевичThe features of distribution are studied and a complex technology for the separation of samarium, europium, and gadolinium is proposed. This technology involves the initial isolation of 70-80% of the europium concentrate by extraction with organophosphorus acids, which makes it relatively easy to obtain pure compounds of samarium and gadolinium in subsequent operations. At the last stage, europium is isolated by chemical reduction and the captured samarium and gadolinium are returned to the beginning of the process. The content of the main substance in the resulting oxides is 99.9-99.99 wt %.
- ПубликацияТолько метаданныеRational Technology for Separation of Rare-Earth Elements of the Yttrium Group(2022) Valkov, A. V.; Petrov, V. I.; Вальков, Александр Васильевич; Петров, Валерий Иванович
- ПубликацияТолько метаданныеEXTRACTION OF A TARGET ELEMENT FROM A MIXTURE OF RARE EARTH ELEMENTS IN A SINGLE-STAGE PROCESS(2022) Valkov, A. V.; Ananyeva, E. A.; Sergievsky, V. V.; Вальков, Александр Васильевич; Ананьева, Елена Алексеевна© 2022, Ore and Metals Publishing house. All rights reserved.The generally accepted method for extracting the required element from a mixture of rare earth elements (REE) is to use two cascades, with elements with a higher ordinal number being separated in one cascade, and those with a lower ordinal number in the second cascade (or vice versa). The features of the extraction and separation of rare-earth and associated elements in ores (actinium, yt-trium) by extraction with mixtures of cation-exchange and anion-exchange ex-tractants are considered. For the indicated extractants, the dependences of the REE distribution coefficients on the atomic number are opposite. Therefore, a change in the composition of mixtures of these extractants makes it possible to regulate their extraction ability and selectivity of the extraction of elements in a wide range. It is shown that the selection of the composition of the mixtures makes it possible to create conditions under which the required element is ex-tracted worse than the others, and it can be isolated in a single-stage extraction process. In this case, the greater the separation coefficients of neighboring REEs during extraction with each of the extractants, the higher the separation selectivity. For the successful isolation of the required element from a mixture of lanthanides within the framework of one extraction cascade, the separation coefficients between neighboring elements during extraction with individual ex-tractants must be at least 3.0. For some elements (yttrium, actinium), there is a shift in the position of an element in the REE series in terms of distribution co-efficients, which consists in the fact that during extraction with one extractant, the distribution coefficient of this element is closer to lanthanum, and with the other extractant, closer to lutetium. It is shown that in this case it becomes possible to separate such an element (for example, yttrium) within one cascade, and the separation coefficients between neighboring elements can be much lower. The separation selectivity increases with the shift of the selected element in the series of lanthanides (according to the distribution coefficients): the greater the shift of the isolated element, the higher the separation factor of the isolated element from the rest of the REEs. Using one extraction cascade instead of two significantly reduces production costs.
- ПубликацияТолько метаданныеExtraction of Rare Earth Elements from the Phosphate Concentrate of Apatite Processing(2023) Val'kov, A. V.; Mesyats, E. A.; Вальков, Александр Васильевич; Месяц, Елена Александровна