THE STUDY OF SORPTION OF NICKEL, COBALT, COPPER IONS RECOVERY FROM MULTICOMPONENT SOLUTIONS BY VARIOUS ION EXCHANGE RESINS

Статья посвящена одному из современных методов и технологий извлечения никеля, кобальта и меди из многокомпонентных растворов - сорбционный метод. В качестве сорбентов выступают ионообменная смола КУ-2-8 и хелатообразующие смолы. Рассмотрен один изметодов удаления веществ, сопутствующих, мешающих извлечению ценных компонентов, одним из которых является железо. The paper considers one of the modern methods and technologies of nickel, cobalt and copper recovery from multicomponent solutions; that is a sorption method. KU-2-8 ion exchange resin and chelating resins are present as sorbents. One of the method of substances which prevent removing valuable components is discussed. One of such substance is considered to be iron.

Layer-by-Layer Coating of MK-40 Heterogeneous Membrane with Polyelectrolytes Creates Samples with Low Electrical Resistance and Weak Generation of H+ and OH− Ions

Ion exchange membranes covered with layers of polyelectrolytes of alternating charges are characterized by very high monovalent selectivity. This allows the use of such membranes for electrodialytic fractionation of multicomponent solutions. However, the very existence of the boundary at which differently charged layers come in contact can hinder a membrane’s effectiveness by limiting its ion permeability, raising levels of H+ and OH− ions (thus shifting the pH) and increasing the electrical resistance of the membrane, which leads to increased energy consumption. To test how these properties would be changed, we created cheap layer-by-layer-modified membranes based on the heterogeneous MK-40 membrane, on which we adsorbed layers of polyallylamine and sulfonated polystyrene. We created samples with 3, 4, and 5 layers of polyelectrolytes and characterized them. We showed that the application of layers did not decrease the efficiency of the membrane, since the electrical resistance of the modified samples, which increased after application of the first oppositely charged layer, declined with the application of the following layers and became comparable to that of the substrate, while their limiting current density was higher and the shift of pH of treated solution was low in magnitude and comparable with that of the substrate membrane.

STUDY OF THE COPPER, MANGANESE AND IRON SELECTIVE EXTRACTION REGULARITIES FROM TECHNOGENIC HYDROMINERAL DEPOSITS BY THE NEUTRALIZATION METHOD

The article presents a factor analysis of the processes of selective concentration of metals by the neutralization method. In this work, the chemistry of the selective extraction process of heavy metal cations from aqueous solutions by the neutralization method is experimentally studied. The mutual influence of the components of matrix solutions on the index of the extraction degree of Cu (II), Mn (II) and iron ions in mono- and multicomponent model systems has been studied. Based on the results obtained, it is established that the use of the neutralization method for the staged isolation and concentration of valuable components from technical solutions in the form of the target product is possible only in a combination of a set of methods: flotation, flocculation and coagulation. It was found that in the process of neutralization of multicomponent solutions, quantitative extraction from technical solutions is possible at the following pH values: Fe (III)– 4.0, Fe (II) – 6.3, Cu (II) – 6.4, Mn (II) – 9.9. It is indicated that a decrease in the initial concentration of Fe3 + ions in a solution leads to an increase in the pH values of the beginning of its precipitation in the form of a dispersed phase of ferric hydroxide. The rational parameters of the pH values of the studied aqueous systems, at which the selective separation and concentration of the main components of technological solutions with a priority content of Fe (III), Fe (II), Cu (II) and Mn (II) ions is possible, have been experimentally substantiated. The extraction of manganese cations, using the method of neutralization from the studied multicomponent solutions, is impossible for the coprecipitation of all designated metal cations. Therefore, based on the high reductive activity of the divalent form of manganese, it is advisable to selectively concentrate it using the method of redox electrodeposition, the products of which are sparingly soluble stable compounds of trivalent and tetravalent manganese. The relevance of research lies in the need to process acidic mine waters of mining enterprises of the copper-pyrite complex in order to significantly expand the raw material base of mining enterprises, as well as to improve the ecological situation of the city-forming mining enterprises of the South Urals. The purpose of the study is to study the material composition of mine waters and develop a technology for the selective extraction of cationic forms of copper, manganese and iron. The object of research is technical mono- and multicomponent solutions with a high content of metal cations: Cu2+, Mn2+, Fe2+ and Fe3+. The subject is the possibility of using the neutralization method for the selective processing of hydromineral resources of mining enterprises of the copper-pyrite complex. Material and research methods. General scientific and special research methods have been used during the work. In the implementation of the experiments, a complex of physicochemical methods of analysis has been used: thermodynamic analysis, UV spectroscopy, chemical and assay analyzes. To determine the content of heavy metal ions, adapted methods of photometric analysis have been used: for copper (II) - with pyramine epsilon, for total iron – with o-phenanthroline, for manganese (II) ions – with their preliminary oxidation to permanganate ions

Features of crystallization of multicomponent solutions: dipeptide, its salt and potassium carbonate

For the first time, all stages of non-equilibrium crystallization of multicomponent peptide solutions have been studied in detail, starting with the formation of colloidal dispersions and ending with the growth...

Hydrothermal Properties of Geologic Fluids

Aqueous fluids are critical agents in the geochemical evolution of Earth’s interior. Fluid circulation and fluid–rock reactions in the Earth take place at temperatures ranging from ambient to magmatic, at pressures from ambient to extreme, and involve fluids that range from nearly pure H2O through to complex, multicomponent solutions. Consequently, the physical and chemical properties of hydrothermal fluids vary widely as functions of geologic setting; this variation strongly impacts fluid-driven processes. This issue will focus on the nature of geologic fluids at hydrothermal conditions and how such fluids affect geologic processes in some major settings.

Polymer-Supported Phosphoric, Phosphonic and Phosphinic Acids—From Synthesis to Properties and Applications in Separation Processes

Efficient separation technologies are crucial to the environment and world economy. The challenge posed to scientists is how to engineer selectivity towards a targeted substrate, especially from multicomponent solutions. Polymer-supported reagents have gained a lot of attention in this context, as they eliminate a lot of inconveniences concerning widely used solvent extraction techniques. Nevertheless, the choice of an appropriate ligand for immobilization may be derived from the behavior of soluble compounds under solvent extraction conditions. Organophosphorus compounds play a significant role in separation science and technology. The features they possess, such as variable oxidation states, multivalence, asymmetry and metal-binding properties, highlight their status as a unique and versatile class of compounds, capable of selective separations proceeding through different mechanisms. This review provides a detailed survey of polymers containing phosphoric, phosphonic and phosphinic acid functionalities in the side chain and covers main advances in the preparation and application of these materials in separation science, including the most relevant synthesis routes (Arbuzov, Perkow, Mannich, Kabachnik-Fields reactions, etc.), as well as the main stages in the development of organophosphorus resins and the most important achievements in the field.