卷 8, 编号 2 (2025)

chemical, mineralogical, granulometric and structural-morphological characteristics of bentonite clays of the Nalchik deposit have been established. The elemental composition contains B (trace amounts), Al, Si, K, Ca, Ti, Fe. It has been revealed that the mineralogical composition of the studied clay is complex of montmorillonite, clinoptilolite and low-temperature trigonal quartz. The montmorillonite content is 53.0 ± 1.1 wt.%. The maximum particle size is 198.7-210.1 μm, the proportion of such particles is 0.69 wt.%. The minimum particle size is 0.6-0.9 μm, the proportion of such particles is 1.22 wt.%. According to the results of differential thermal analysis, 4 endoeffects were recorded, the total mass loss on sample calcination was 16.5%, taking into account the loss of free water - 9.5 wt.%. The adsorption characteristics of the analyzed bentonite were studied using “model” pollutants – nickel (II) cations and methylene blue dye. It was found that the adsorption isotherm of nickel (II) ions belongs to class L type 3, and the adsorption isotherm of methylene blue belongs to class L type 2 according to the Gils classification. The results of the study showed that bentonite clay from the Nalchik deposit is capable of purifying wastewater to the maximum permissible concentration of cationic pollutants. Objectives: to investigate the material composition and adsorption properties of bentonite clay from the Nalchik deposit. Methods. To determine the elemental, phase and granulometric composition, the following equipment was used: transmission electron microscope JEM-2100 (Jeol, Japan), diffractometer Ultima IV (Rigaku, Japan), combined analyzer TG/DTG/DTA SDT Q600 (TA Instruments, Inc., USA), particle size analyzer Microtrac S3500 (USA), as well as laboratory instruments and reagents. Results. The mineralogical composition of the clay sample from the Nalchik deposit was established; the mass content of montmorillonite was determined. The granulometric composition was studied. The adsorption processes of the clay sample in relation to the organic dye methylene blue and nickel (II) ions were investigated. Conclusions. The mineralogical composition of the clay sample from the Nalchik deposit was determined: montmorillonite, clinoptilolite and low-temperature trigonal quartz. The montmorillonite content is 53.0 ± 1.1 wt.%. The maximum particle size of the fraction in the studied clay sample is 198.7-210.1 μm, the proportion of such particles is 0.69 wt.%. The minimum particle size of the fraction is 0.6-0.9 μm, the proportion of particles is 1.22 wt.%. The adsorption processes of the clay sample in relation to the organic dye methylene blue and nickel (II) ions were studied. It was shown that the clay of the Nalchik deposit is capable of purifying wastewater from the specified cationic pollutants to the regulatory requirements.

objectives: the purpose of the work is to consider bioethanol as a promising renewable fuel, analyze its production technology, raw material base, technological generations, as well as the structure of the global market and its environmental role. The methods consist in analyzing the historical development of technology. A review of the raw material base (sugar-containing, starch-containing, lignocellulose materials) and an analysis of global experience (Brazil, USA, EU) and the potential of Russia. The article highlights the history of bioethanol development, starting with the first developments of Henry Ford and ending with modern trends and technologies. The factors contributing to the growing interest in bioethanol production technology are analyzed. The different generations of bioethanol (first, second, third and fourth) are considered in detail. Special attention is paid to the overview of the global bioethanol market, its current state and growth forecasts due to strict environmental regulations and the increased use of biofuels in the transportation industry. Results. The data on different generations of bioethanol, their advantages and disadvantages are systematized. A comparative analysis of the effectiveness of different types of raw materials (yield, ethanol yield) is presented. An assessment of Russia's prospects in the development of the bioethanol industry is given against the background of international experience. The article discusses the raw material base and technologies for the production of first-generation bioethanol from sugar cane, corn, wheat, and sugar beet. In addition, promising areas of technology for the production of bioethanol of the second and third generations are being considered. Where lignocellulose raw materials such as wood waste, straw waste, and fast-growing energy crops are used as raw materials. Special attention is paid to comparing the effectiveness of different types of raw materials: sugar-containing crops (sugar beet, cane), starch-containing (cereals, potatoes) and lignocellulose waste (straw, wood, miscanthus). The ecological role of bioethanol and its importance for energy security are emphasized. Conclusions. Sugar-containing raw materials demonstrate high efficiency, but their use is limited by seasonality and competition with the food industry. Starch-containing cultures provide stable ethanol yield, but require additional hydrolysis steps. Lignocellulose raw materials are the most promising direction for second—generation bioethanol. It solves the problem of waste disposal and does not compete with food resources, but requires more sophisticated processing technologies. The market leaders are Brazil (cane ethanol), the USA (corn), and the EU (lignocellulose technologies). Their success is linked to government support and environmental regulations. Russia also has significant raw material potential for the development of this industry. The article is based on current research and contains comparative characteristics of raw materials, which makes it useful for specialists in the field of bioenergy, agriculture and ecology.