This study investigates the extraction of rhenium using trialkylbenzyl ammonium chloride (TABAC) as an alternative to trialkylamine (TAA) for recovering rhenium from highly diluted solutions. Rhenium, present as ReO₄⁻ over a wide acidity range, was extracted via an anion exchange mechanism in single-stage experiments monitored by inductively coupled plasma mass spectrometry (ICP-MS). Key variables, including pH, acid concentration, and the concentrations of extractant and metal, were examined. The results demonstrated a high extraction efficiency exceeding 99% within a pH range of 2 to 7 and from solutions containing sulfuric or hydrochloric acid at concentrations of 0.1 to 3.0 M (mol/L). However, extraction from nitric acid solutions was less efficient, with less than 30% recovery. Performance for both TAA-kerosene and TABAC-kerosene followed the order H₂SO₄ > HCl > HNO₃. The optimal TABAC concentration was 10⁻² M (mol/L) in kerosene. TABAC also showed higher selectivity than TAA, with separation coefficients Re/Mo = 66.8 and Re/W = 55.8 in 0.1–1.0 M (mol/L) sulfuric acid. Based on equilibrium studies, the complexes formed during extraction were identified as [R₃R′NH]ReO₄. This approach may offer environmentally friendly and cost-effective benefits for large-scale industrial applications, enabling efficient recovery of valuable rhenium while reducing waste and environmental impact.

In this study, a commercial anion-exchange resin (D301), known for high regenerability but limited selectivity, was chemically modified to enhance its sorption performance. The modification included graft polymerization of glycidyl methacrylate followed by thiourea functionalization, yielding a new sorbent, TD301, with chelating functional groups. Characterization using SEM/EDS, IR spectroscopy, XPS, and zeta potential measurements confirmed the successful introduction of sulfur- and nitrogen-containing groups, increased surface roughness, and decreased surface charge in the pH range 2–6. These changes shifted the sorption mechanism from nonspecific ion exchange to selective coordination. Sorption properties of TD301 were evaluated in mono- and bimetallic Mo–W systems, as well as in solutions obtained from real ore decomposition. The modified sorbent showed fast sorption kinetics and high selectivity for Mo(VI) at pH 1.5, while retaining high W(VI) uptake at pH 0.5. In binary systems, separation factors (α) reached 128.4, greatly exceeding those of unmodified D301. In real leachates (Mo ≈ W ≈ 0.04 g/L), TD301 selectively extracted W at pH 0.66 and Mo at pH 1.5. These findings demonstrate that TD301 is an effective sorbent for pH-dependent Mo/W separation in complex matrices, with potential for resource recovery, wastewater treatment, monitoring, and suitability for repeated use.

The article describes the effect of heat treatment on the structural-phase state and properties of a multilayer Cr-Al-Co-Y coating obtained by magnetron sputtering. Heat treatment was carried out at 400, 800 and 1000 °C. The study of the microstructure was carried out by electron microscopy with energy dispersive analysis and powder X-ray diffraction. The surface of the samples was studied by atomic force microscopy. The thickness of the Co-Cr-Al-Y coatings was 1.5–1.7 ± 0.2 µm. The obtained coatings are characterized by a hardness of 4.7–6.4 GPa. A distinctive feature of the layers is the absence of a crystalline structure in some areas of the coating. The main process occurring during the thermal treatment is the formation of a spinel-type phase. For a single-layer sample after heat treatment at 400 °C, it was not possible to fix extraneous reflections except for the reflections of the silicon substrate 111 and 220. For the rest of the samples, the appearance of reflections of a number of phases was noticed, such as: SiO₂, CoO, AlSi_0.5O_2.5 and CrAl_0.42Si_1.58. An increase in the treatment temperature up to 800 °C did not lead to significant changes. In the case of the multilayer sample, the reflections of various impurity phases disappeared and the Co₃O₄ phase was formed. For samples treated at 1000 °C, the formation of a spinel-type phase (Co₃O₄-CoCr₂O₄) was observed in all cases. Data on the structural-phase state and properties of the multilayer Co-Cr-Al-Y coating can be used to predict the nature of such coatings after heat treatment.

The separation of rare-earth elements (REE) from a neodymium magnet has been widely studied last year. During the research it was identified that the waste of computer hard disk contains 25.41 % neodymium, 64.09 % iron, and <<1 % boron. To further isolate rare-earth metals, the magnet was acidically dissolved in open and closed systems. In both methods of dissolution, concentrated nitric acid was used. The difference between these methods is the conditions of dissolution of magnet. The magnet was dissolved in a microwave sample preparation system at different temperatures and pressures in a closed system. In the open system, the acid dissolution of the magnet is conducted at room temperature. 0.2 g of the neodymium magnet sample was taken under two conditions, and the dissolution process in the closed system lasted 1 hour, and in the open system 30-40 minutes. The open system is a non-laborious, simple, and cheap method of dissolving the magnet by comparing both systems. Therefore, an open sample preparation system is used for further work. To remove the iron in the magnet, oxalic acid was used and REEs are precipitated as oxalates under both conditions. According to the result of the Inductively coupled plasma mass spectrometry (ICP-MS) method, it was identified that the neodymium and iron contents in the precipitate are 24.66 % and 0.06 %, respectively. This shows that the iron has almost completely passed to the filtrate

In this paper, the main characteristics of the natural bitumen of the Munaily-Mola oil sands were studied with comparison crude oil of Karazhanbas oil field. During the experiment, the density, heating value, ash content and elemental composition of natural bitumen were determined, and these parameters were compared with the properties of Karazhanbas crude oil. As well as oil, resin and asphaltene fractions of both hydrocarbons were separated and each of them were analyzed at a Fourier transform IR-spectroscopy Spectrum-65 with 450-4000 cm−1 range. According to these indicators, it is concluded that natural bitumen is a heavy hydrocarbon raw material with highly resin-asphaltene compounds. Like Karazhanbas oil, natural bitumen can be used as a raw material for various petrochemical products. By finding ways of effective processing of natural bitumen, it can be used in useful areas of the national economy.

The development of technologies for processing oil residues is relevant and promising for Kazakhstan, since the main oil reserves of hydrocarbons in the country are in heavy oils. This paper describes the study of the influence of technological modes on the yield and hydrocarbon composition of products formed because of cracking of commercial fuel oil and fuel oil M-100 in the presence of air in the reactor. For catalysts preparation, natural Taizhuzgen zeolite and Narynkol clay were used. It was found that the introduction of air into the reaction zone, in which oxygen is the initiator of the cracking process, significantly increases the yield of the middle distillate fractions. In the presence of air, the yield of diene and cyclodiene hydrocarbons significantly increases compared to cracking in an inert atmosphere. According to the data of IR spectral analysis of M-100 grade oil fractions, in addition to normal alkanes, the final sample contains a significant amount of olefinic and aromatic hydrocarbons. On the optimal catalyst, owing to oxidative cracking of fuel oil, the following product compositions (in %) were established: Fuel oil M-100: gas – 0.8, gasoline – 1.1, light gas oil – 85.7, heavy residue – 11.9, loss – 0.5 and total – 100.0%; commodity Fuel oil (M-100): gas – 3.3, gasoline – 8.4, light gas oil – 84.3, heavy residue – 4.0, loss – 0 and total – 100.0%.