In recent years, there has been an increased demand for nickel-cobalt-containing batteries, which in turn adds a lot of interest in the production of these metals in large volumes. Due to a contraction of the volume of nickel sulfide ores, the majority of producers consider laterite deposits as a potential source of nickel and cobalt. However, processing laterites by traditional pyrometallurgical methods is economically unprofitable. Research has shown that the use of combined and hydrometallurgical methods can be promising. This article is devoted to a review of the results of research and articles on the extraction of nickel and cobalt from laterite ores over the past 20 years. Current technological schemes for the production of nickel and cobalt using combined manufacturing processes are presented, as well as the results of scientific research on increasing the recovery degree of nickel and cobalt from low-grade refractory laterite ores using preliminary activating roasting, various leaching reagents, oxidizing agents, bacteria, etc. Growing interest in nickel production has also been observed in Kazakhstan and research work on the extraction of target metals from local laterite ores is being intensively carried out. According to the investors’ forecast, the first mining in the republic and full commissioning of nickel production are expected in 2025. This study was funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (grant no. AP19680477).

The development of combined enrichment technologies becomes more significant due to the decreasing of the processed ores quality and involvement in the processing of poor, refractory ores. The difficulty in the flotation enrichment of mixed and oxidized polymetallic ores and intermediate products lies in the effective sulfidization of the surface of oxidized minerals. The sodium sulfide reagent used in flotation does not always provide complete sulfidization of the mineral surface. On the intermediate product of lead-zinc ores related to the phase composition of mixed ores, flotation studies were carried out on the original product and after preliminary sulfidization by the pyro-metallurgical method. It was found that in the pre-sulfidizied product, the extraction of zinc increased to 17.23 %, and lead to 10.07 %, compared with the original product without pre-treatment.

The article discusses the methods of processing vanadium-containing raw materials, including methods of pre-sintering and leaching of raw materials, extraction and precipitation of vanadium-containing solutions. In addition, the specific methods used for each type of vanadium-containing raw materials are described, with a description of their advantages and limitations. The article also briefly analyzes a number of the main influencing factors and mechanisms of various processes. Some research prospects are proposed to improve the methods of vanadium concentration from vanadium-containing raw materials. The article considers the potential of extraction and processing of vanadium-containing black shale ore, as well as vanadium-containing titanomagnetite ores. Spent vanadium catalysts used in petrochemical processes can be a potential source for vanadium extraction. In addition, vanadium-containing bauxite raw materials, oil and steel production slags can be promising raw materials for further extraction of vanadium. The article presents methods for processing vanadium-containing raw materials, including methods of pre-sintering and leaching of raw materials, extraction and precipitation of vanadium-containing solutions. In addition, the specific methods used for each type of vanadium-containing raw materials are described, with a description of their advantages and limitations. The article also examines the potential of extraction and processing of vanadium-containing black shale ore, vanadium-containing titanomagnetite ores as a potential source for vanadium extraction. Vanadium-containing bauxite raw materials and steelmaking slags can also be promising raw materials for further extraction of vanadium.

This article presents the results of the high-temperature hydrolysis process of FeCl2×4H2O and the study of iron oxide powder properties produced. It is observed that the process has a topochemical character and proceeds in a diffusion zone. Conditions sufficient for practically complete decomposition of FeCl2×4H2O are a temperature in the range of 803–903 K and a duration of 40 minutes. The powder, obtained as a result of high-temperature hydrolysis of FeCl2×4H2O, is represented by an ultradisperse powder of iron oxides of 10–100 nm in size (average — 20 nm), having a basically round shape. The results of microprobe, X-ray phase analyzes, magnetic susceptibility analysis, and Mössbauer spectroscopy have revealed that the product of hightemperature hydrolysis consists of a mixture of iron oxides consisting of magnetite and hematite.

This work studies the removal of uranium ions from chemically leached solutions by sorption using two weak and two strong base anionites. Batch sorption experiments were performed to evaluate the optimum conditions at pH 1.2–2.2, 1.0 g resin dose for 1–12 h contact time at room temperature. These experiments addressed sorption kinetics and sorption isotherm. The maximum sorption capacity reached 55.8 mg/g at room temperature. The kinetics data are well described by the pseudo-second-order kinetic model at initial uranium concentration of 0.62 mg·L⁻¹. To describe sorption kinetics pseudo-first-order, pseudo-second-order and intraparticle diffusion models were proposed. Studies indicated that the sorption of uranium can be fitted by a pseudo-second-order kinetic model very well. Equilibria were described by Langmuir, Freundlich, and Dubinin–Radushkevich equations. The experimental sorption isotherm is successfully described by the Langmuir model.