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Hydrocarbon deposits occurring at a depth of more than 4.5 km are poorly studied, although they are situated on all continents. This slows down the assimilation of these resources. Analysis of the information from the database of the Institute of Petroleum Chemistry of Siberian Branch of the Russian Academy of Sciences on the physicochemical properties of oil showed that the largest oil reserves are concentrated at depth down to 3000 m. The features of the changes of physicochemical properties of oils were established to depend on the depth of occurrence. It is shown that in different oil basins the density and viscosity of oil decreases with depth. The content of sulphur, resins and asphaltenes decreases with depth, while the content of petroleum gas and fractions increases with depth. The analysis of hydrocarbon occurrence conditions at great depths was carried out. The prospects of oil and gas potential of the deep sediments of oil and gas basins in Russia and Western Siberia, in particular, are evaluated.

Black coal is formed by a carbon framework originating from metamorphism of condensed polycyclic organic compounds. This framework includes volatile organic substances, as well as a definite amount of mineral admixtures that form ash after coal combustion. The content of individual polycyclic aromatic hydrocarbons (PAHs) in coal depends on the nature of initial plant material that participated in the stages of coal formation, and on thermodynamic conditions of this process. One of the major representatives of PAHs possessing a strong carcinogenic effect is benz(a)pyrene. The group of PAHs compounds also includes phenanthrene, fluoranthene, pyrene, chrysene, which are the major components of emissions during coal production, transportation, storage, concentrating, gasification, coking and combustion, and serve as convenient tracers to evaluate the pollution of the atmosphere, surface waters, and soil. The latter plays the part of a special accumulator into which PAHs get as a result of the global transport of emissions from anthropogenic sources and arrival from natural sources into the atmosphere. Because of this, soil relates to the most representative objects to study PAHs accumulation. The presence of these compounds may play the role of indicators depicting the presence of pollution source. As a rule, PAHs are determined by means of gas and high-performance liquid chromatography. Gas chromatography in combination with mass spectrometry appears to be the most promising method. To obtain reliable data on PAHs content in various objects, special attention is paid to sample preparation (extraction, purification, concentrating). Methodically correct arrangement of this stage allows excluding a noticeable fraction of the possible error of quantitative determination. The paper presents a review of the methods of PAHs extraction from solid matrices, in particular from fossil coal. It is demonstrated that all ranks of coal may be the sources from which toxic and carcinogenic PAHs enter various environmental objects. A review of the scientific foundations and modern practical methods of PAHs extraction from black coal is presented, the data on the distribution of the representatives of this group of compounds and on the prediction of carcinogenic activity during coal mining, transportation and processing are assessed.

The thermal stability and reactivity of heavy oil asphaltenes at temperatures below 300 °C were evaluated. In this work, we used an original method of sequential stepwise thermolysis of asphaltenes at temperatures of 120, 230, and 290 °C in the inert gas flow with the removal of the resulting products from the reaction zone at each stage of the process. This approach allows us to minimise the occurrence of secondary reactions to assess the true reactivity of asphaltenes, and also to take into account the differences in the binding energies in their molecules to determine the real thermal stability of asphaltenes within different temperature ranges. It was established that when asphaltenes are heated to 300 °C, they undergo intense thermal degradation with the formation of gas, oils, resins and insoluble coke-like substances. In the process of sequential stepwise thermolysis up to 290 ºС, the conversion of heavy oil asphaltenes exceeds 90 %. At a temperature of 120 °C, the conversion of asphaltenes can reach 13 % with the formation of mainly resinous substances (more than 10 mass %). An increase in thermolysis temperature to 230 °C leads to an increase in the conversion of asphaltenes to 40 % due to their ability to generate significant amounts of gas and oils (14-18 mass %), as well as coke-like products (2-10 mass %) under these conditions. In the process of subsequent thermolysis of asphaltenes at a temperature of 290 ºС, the maximum amount of coke-like substances (29-37 mass %) is formed. The yield of low molecular weight products is also significant and amounts to about 20 mass %. Thus, at temperatures below 300 ^oС, asphaltenes of heavy oils are characterised by low thermal stability and extremely high reactivity in thermal processes. The results obtained must be taken into account when developing new and modernising existing oil refining technologies.

Disorders of hematopoiesis caused by the action of various factors (hemotoxic substances, drugs, cytotoxic drugs, radiation) lead to a deviation from the norm and the development of the diseases varying in complexity. The restoration of hematopoiesis under extreme conditions is vital, and the search for the drugs stimulating hematopoiesis is an extremely urgent task. The most interesting agents are low molecular weight compounds that can stimulate hematopoiesis in case of its disorders. The presented literature review discusses various factors leading to hematopoietic disorders, and drugs that have shown sufficient effectiveness in eliminating these disorders, in particular with cytostatic therapy and the treatment of hemolytic pathologies. The review can be useful in the search for agents that stimulate hematopoiesis, and is addressed not only to medical and chemical professionals, but also to a wide range of readers.

The results of a comprehensive study of an illite-containing sorbent (IS) are presented. The sorbent was obtained by means of acid-water treatment of the sample of clay-salt slimes, which are industrial wastes of JSC “Belaruskali” (the Republic of Belarus). The material composition of the IS is established, indicating that the main clay mineral is illite, the content of which is 65.2 mass %. The specific surface area of the IS is determined to be (66 ± 4) m²/g. According to mineralogical composition, the IS refers to hydromica group. The sorption ability of the IS sample to extract ¹³⁷Cs⁺ from natural waters of different chemical composition was studied. It is shown that the major ions of natural waters, namely Ca²⁺ and Na⁺, do not have a significant effect on the sorption of ¹³⁷Cs⁺ by the IS for pH of water solution within the range of 5-9. It is determined that the IS has shown high selectivity with respect to ¹³⁷Cs⁺ sorption from aquatic medium, and the main competitor is K⁺ ion. When K⁺ concentration in the aquatic medium is higher than 0.5 mol/dm³ in, the sorption of ¹³⁷Cs⁺ on the IS is completely inhibited. It is established that IS sorbs ³⁷Cs⁺ from natural water 2-4 times more efficiently than clinoptilolite of the Shivertuinskoye deposit (Chita region, Russia), which is currently used as a sorbent of ¹³⁷Cs⁺. The obtained results indicate the possibility and prospects of using CSS reserves accumulated in the Republic of Belarus to manufacture the IS and to use it for purification of aquatic medium from ¹³⁷Cs⁺, as well as for solving a number of environmental problems, including rehabilitation of radioactively contaminated soils and territories.

The effect of KOH concentration on the rate of the target reaction of metal tellurium deposition from alkaline tellurite solutions and on the rate of the side reaction of tellurium dissolution was studied by means of voltammetry with the linear potential scanning on a graphite electrode coated with tellurium deposit. It was established that KOH only weakly (with a change by 5-10 %) affects the rates of the target and side reactions within the range of alkali concentrations 2-4 M, which is used for the production of tellurium. The reasons of a decrease in the rates of the target and side reactions at low alkali concentrations were considered. It was shown that the target and side cathode reactions have the diffusion-determined nature in the range of alkali concentrations 0.5-4 M with tellurium deposition and 0.1-4 M with tellurium dissolution. The side cathode reaction of Те dissolution has a one-electron mechanism, and it requires 20 % of the amount of electricity used for tellurium deposition.

Nickel-containing zeolite samples were prepared by dry mechanical mixing of ZSM-5 zeolite (silica modulus 40) and nickel powder with the average particle size of 50 nm in the amount of 0.5 mass %. The samples were mechanically treated in a ball mill for 24-120 h. The crystallinity of the initial zeolite and mechanically treated nickel-containing zeolites was determined by means of IR spectroscopy and XRS. The degree of zeolite crystallinity was revealed to decrease due to loosening of the structure of both the polycrystalline units and primary crystallites as a result of mechanical treatment. The analysis of the state of nanosized nickel in zeolite catalysts by means of UV spectroscopy and XPS revealed almost complete absence of the oxidation of nickel particles. The morphology of the crystals of the initial and mechanically treated zeolites was studied by means of the high resolution transmission electron microscopy. Mechanical treatment was determined to cause a decrease in the particle size of initial ZSM-5 and partial migration of nickel from the surface into zeolite pores. The size of nickel particles decreases during the initial period of mechanical treatment, while a longer mechanical impact, on the contrary, contributes to the agglomeration of nickel particles. The particles of ZSM-5 zeolite in the initial sample look like coarse agglomerates with the overall size of several micrometres. The agglomerates are composed of smaller polycrystalline units 0.5-1.0 mm in size. However, the primary particles are zeolite crystals 50-100 nm in size. Mechanical treatment causes disintegration of coarse zeolite agglomerates into smaller polycrystalline units less than 1 mm in size; primary crystallites comprising the polycrystalline structure are dispersed, too, decreasing in size to ~50 nm. According to the data of low-temperature desorption of nitrogen, mechanical pretreatment of nickel-containing zeolite causes a decrease in its specific surface and pore volume. The changes in the physicochemical properties of the Ni/ZSM-5 catalyst caused by mechanical treatment should promote selective conversion of feedstock components and flexibility of the regulation of selective formation of target products in oil refining processes.

A fundamentally new concept of providing the population with high-quality drinking water is proposed, associated with the transfer of drinking water supply to cities and villages to the use of autonomous block installations for water purification in the sites of its direct consumption. Autonomous membrane installations for collective and individual use with biotesting and analytical control are developed. In these installations, preliminary water purification is carried out with the help of microfiltration tubular membranes made of lignocellulose (wood) and ceramic membranes made of clay minerals, which retain mechanical and colloidal impurities. The concentrations of these impurities after purification meet the drinking water standards. A technological scheme is developed for water purification from nitrate ions to drinking conditions with the production of mineral fertilizers through a rational combination of reverse osmosis and an improved electrodialysis process.

Complex coagulants comprise a developing and very promising area for the processes involved in the treatment of natural and waste waters. In spite of somewhat higher cost, complex coagulants are devoid of the disadvantages of many classic coagulants and demonstrate high efficiency in water purification from metals, fats, oil products and suspended matter; they also provide a substantial decrease in the concentrations of dissolved organic substances (chemical oxygen demand). The simplest method of manufacturing complex coagulants is the introduction of an additive composed of the products of hydrolysis of titanium-containing compounds into the classic reagents based on aluminium or iron salts. Soluble titanium salts or titanium dioxide may serve as the source of titanium compounds. The waste waters of dairy industry contain a large amount of dissolved organic substances and emulsified fat, so the purification of these waters is one of the most complicated problems. Trial coagulation treatment of model wastewater containing whey showed a high efficiency of complex titanium-containing reagents. Complex coagulants exceeded traditional reagents in efficiency by 10-15 % as average, and the rate of precipitate filtration was 1.2-1.5 times higher. The sediment had a looser structure, did not clog the pores of the filtering material, and readily gave moisture off. Tests of the best samples of complex reagents with the combined household and industrial waste waters of the dairy processing enterprises of the Moscow Region confirmed their high coagulation characteristics with respect to the most common pollutants, and the acceleration of sludge filtration processes will significantly reduce the capital costs of building local sewage treatment plants. The residual content of titanium ions in water, when using the entire line of modified coagulants, did not exceed the maximum permissible level for fishery water bodies.

Porous carbon materials with a specific surface area of 1200-1500 m²/g were obtained by carbonization of rice husks at 500 °C, followed by subsequent activation using potassium hydroxide at a temperature of 700, 800, 900 °C, and studied by means of Raman spectroscopy and electrochemical methods. It was established that mechanical activation of rice husks makes it possible to increase the specific surface area (to 2315 m²/g) and the volume of micropores (to 0.84 cm³/g) in the carbon material. As a result, an increase in electrical capacity and a decrease in the internal resistance of supercapacitor cells with electrodes based on them are achieved.