Тип публикации: статья из журнала
Год издания: 2022
Идентификатор DOI: 10.17580/tsm.2022.06.05
Ключевые слова: binary extraction, rare-earth metals, di-(2-ethylhexyl)phosphoric acid, countercurrent extraction cascade, modeling, extraction stages, isotherm
Аннотация: The use of binary extractants (BE) in schemes of countercurrent extraction cascades designed for the separation of rare earth metals (REMs) has been studied. It has been shown that the main difference between the use of BE and cation-exchange extracts (CE) is the possibility of using deionized water in the re-extraction cascades, rПоказать полностьюather than solutions of mineral acids. When optimizing the REM separation scheme, a mathematical model was used to dynamically calculate the distribution of separated metals over the stages of counterflow extraction cascades. The modeling of cascades was carried out on the basis of the physicochemical description previously obtained by the authors of the processes of extraction of REM nitrates with various BE compositions prepared on the basis of industrial cation- and anion-exchange extractants. Calculation of the balance of lanthanides during successive separation by stages of cascades was performed for the initial mixture of REM nitrates with the ratio of elements corresponding to the composition of the ore of the Chuktukonskoe rare metal deposit. A scheme of cascades is proposed for isolating in pure form the five REMs of light and light/medium groups (Pr, Nd, Sm, Eu, Gd) most demanded by the industry, concentrate of La, Ce, and concentrate of REM of medium/heavy and heavy groups. The scheme includes 10 countercurrent extraction cascades with a total number of extraction stages of 390. The scheme uses BE based on di-(2-ethylhexyl)phosphoric acid, synthetic fatty acids, tri-n-octylamine, and an industrial diluent. For the proposed scheme, mineral acid is used only at the stage of obtaining REM nitrates from the initial oxides; 1.8 kg (65%) of nitric acid is consumed per 1 kg of REM oxides. For the precipitation of REM carbonates from re-extracts, the consumption of sodium carbonate is approximately 1 kg per 1 kg of the initial REM oxides. The use of BE in comparison with CE makes it possible to significantly reduce the consumption of mineral acids and bases during the separation and production of individual REMs.
Журнал: Цветные металлы
Выпуск журнала: № 6
Номера страниц: 45-50
ISSN журнала: 03722929
Место издания: Москва
Издатель: Издательский дом "Руда и металлы"