Mine water from non-ferrous metal deposits is often contaminated with nickel and manganese ions. The entry of these ions, especially nickel, into surface waters and underground aquifers is undesirable since it has a negative effect on living organisms and worsens the condition of drinking water sources. One of the promising methods for selectively extracting nickel ions and obtaining an eluate suitable for further use is sorption by weakly acid cation exchangers with chelate groups of iminodiacetic acid. As part of the study, sorption isotherms of nickel and manganese ions by Lewatit MonoPlus TP 207 cation exchanger in mono- and bicomponent systems were obtained. In monocomponent systems, the maximum static exchange capacity (SEC) of the cation exchanger for nickel ions is 952 mmol/dm3, and in bicomponent systems – 741 mmol/dm3; for manganese ions– 71 mmol/dm3 and 49 mmol/dm3, respectively. It is obvious that the studied cation exchanger has a greater capacity for nickel ions than for manganese ions. The influence of a temperature increase from 300 to 330 K on the sorption of nickel and manganese ions was established: in monocomponent systems, the maximum degree of extraction of the former increases from 65 to 77 % (SEC from 337 to 399 mmol/dm3), and the latter from 21 to 35 % (SEC – from 140 to 229 mmol/dm3); in bicomponent systems, the extraction of nickel ions increases from 59 to 78 % (SEC – from 307 to 429 mmol/dm3), and manganese ions decreases from 20 to 17 % (SEC – from 164 to 131 mmol/dm3). The predominant increase in the indicators is due to the filling of the sorption centers of the ion-exchange resins, which are energetically unfavorable for the exchange of counterions at a lower temperature. The influence of the pH of the solution on sorption was determined: the intensification of the process for nickel ions is observed in the pH range of 8.0-8.5 in a monocomponent solution and 8.0-9.0 in a bicomponent solution, for manganese ions in the range of 8.0-9.5 in both cases. The increase in the degree of extraction of ions and the exchange capacity of the ion exchanger with increasing pH is associated with the appearance of singly charged hydroxocations, dissociation of the functional groups of the sorbent and, to some extent, with the subsequent formation of insoluble forms of nickel and manganese. However, with increasing pH, a decrease in the selectivity of nickel extraction is observed: the ion separation coefficient decreases from 14.0 to 6.0 in the pH range of 6.0-11.0.

Исследована в динамическом режиме сорбция ионов индия из поликомпонентных растворов с предварительно восстановленным железом (III), содержащих, г/дм 3 : 0,084 In 3+ , 6,2 Fe 2+ , 67,0 Zn 2+ и 19,6 H 2 SO 4 , на реагенте Metosol. Последний представляет собой монтмориллонит состава (Na,Ca) 0,3 (Al,Mg) 2 Si 4 O 10 (OH) 2 (H 2 O) n , модифицированный ди(2-этилгексил)фосфорной кислотой. Динамика поглощения им ионов металлов изучена методом фронтальной хроматографии. Определены значения рабочей (ДОЕ) и полной (ПДОЕ) динамических обменных емкостей минерального сорбента в зависимости от удельной скорости пропускания и температуры элюента. Обоснованы и рассчитаны основные параметры сорбционной технологии селективного извлечения индия из технологических растворов цинкового производства на реагенте Меtоsol в колонках с последующей десорбцией металла раствором соляной кислоты (1 : 1).

The aim of this work was to study the adsorption of indium from aqueous solutions on modified highly dispersed aluminosilicates for the recovery of indium from technological solutions. The adsorption isotherms of indium, iron and zinc from multi component solutions on modified by di(2-ethylhexyl) phosphoric acid montmorillonite were obtained. It was shown that adsorption processes can be reliably described by models of Langmuir and Freundlich (R2  =  0.96–0.99). The shape of the isotherms is determined both by the surface properties of the sorbent and forms of presence of metal ions in aqueous solutions. The highest value of Langmuir constant Kads = 422.65 for reagent "Metоsol" was obtained for ions of indium, which indicates the preferential affinity of the sorbing mineral to this element, since the corresponding figures for the ions Fe2+ (1.09) and Zn2+ (0.78) are close to unity. At sorption of metal ions from model solution in the range of acidity of 1-20 g/dm3 of H2SO4 the extraction of indium remains unchanged at ~70 %, and iron – is reduced from 39 to 15% of the initial content. With the further increase of acidity to 100 g/dm3 of H2SO4, the recovery of indium is reduced to 40 %; iron down to 14 %. In the examined range of concentration of sulfuric acid the extraction of zinc is from 6.0 to 7.5 percent. The value of the static exchange capacity for the studied metals are mmol/g: 0.39–0.23 of indium; 0.11–0.04 of iron(III); 0.05–0.04 of zinc. A rank of affinity of reagent "Metоsol" to extract the metal ions from solution with pre-reduced iron(III)  was In3+ > Fe2+ > Zn2+ which determines the feasibility of its use for the selective adsorption of indium from the complex composition of technological solutions of zinc production.

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Представлены результаты экспериментальных исследований по активации осинового угля зольностью 2,5 % водяным паром на выход и свойства полученного активного угля. Показано, что для активации лучше использовать уголь из спелой осины, а не из тонкомера, поскольку значения зольности у осинового угля из тонкомера сравнительно высокие и не могут гарантировать соблюдение этого показателя в товарном АУ. В этой связи необходимо применять технологию, обеспечивающую сравнительно высокий выход продукта. В наших исследованиях это условие выполнялось путем использования Z–образной вставки в печи активации. The results of experimental studies on the activation of aspen coal with an ash content of 2.5 % by water steam on the yield and properties of the resulting activated carbon are presented. It is shown that for activation it is better to use coal from ripe aspen, rather than from thin aspen, since the ash content of aspen coal from thin aspen is relatively high and cannot guarantee compliance with this indicator in the commercial activated carbon. In this regard, it is necessary to use a technology that provides a relatively high yield of the product. In our studies, this condition was met by using a Z-shaped insert in the activation furnace.