This work is devoted to the study and application of the pyrolysis method for the effective utilization of activated sludge obtained at municipal wastewater treatment plants. Activated sludge is a colloidal-dispersed system with high humidity and sol content, which poses a challenge for its treatment and disposal. During the study, its humidity and ash content were determined, experiments on the thermal decomposition of silt sediments were carried out, during which data on the material balance of the process of thermal decomposition of silt sediments were obtained; the ecological advantages of this method in comparison with traditional methods of disposal are highlighted. As a result of experiments, it was found that the pyrolysis method makes it possible to efficiently process activated sludge and obtain valuable products, including solid coal and liquid fractions, which have potential value for various industries, such as the production of fuels, chemical products and fertilizers. The advantages of this method include reducing the volume of waste, obtaining valuable resources from activated sludge and reducing the negative impact on the environment. The environmental safety of the pyrolysis method makes it one of the most promising methods of processing activated sludge. In addition, this study highlights the importance of sustainable waste management methods that can reduce the negative impact on the environment and promote the use of renewable resources. The activated sludge pyrolysis method is an effective and environmentally safe way to turn waste into useful products, which is important for sustainable development and reducing the environmental burden on natural resources. These results and conclusions have the potential for practical application in the field of waste management and production, and can also serve as a basis for further research and development in the field of recycling and recycling of various types of waste in order to create more sustainable technologies.

Keywords: activated sludge, pyrolysis, processing of activated sludge, thermal decomposition.

Dmitrij Ju. Kiselev (Kazan, Russian Federation) – 1st year Master's Student of the Department of Chemical Technology of Wood of Kazan National Research Technological University (68, Karl Marx Street, Kazan, 420015; e-mail: dmskkiselev@gmail.com).

Aigul R. Valeeva (Kazan, Russian Federation) – Ph.D. of Technical Sciences, Associate Professor, Department of Chemical Technology of Wood of Kazan National Research Technological University (68, Karl Marx Street, Kazan, 420015; e-mail: samirhanova@rambler.ru).

Rimma M. Khaziakhmedova (Kazan, Russian Federation) – Assistant, Department of Chemical Technology of Wood of Kazan National Research Technological University (68, Karl Marx Street, Kazan, 420015; e-mail: rimmo4ka_0694@mail.ru).

Almira I. Valiullina (Kazan, Russian Federation) – Assistant, Department of Chemical Technology of Wood of Kazan National Research Technological University (68, Karl Marx Street, Kazan, 420015; e-mail: almi.sabirzyanova@ya.ru).

Vladimir N. Bashkirov (Kazan, Russian Federation)– Doctor of Technical Sciences, Director, Department of Chemical Technology of Wood of Kazan National Research Technological University (68, Karl Marx Street, Kazan, 420015; e-mail: vlad_bashkirov@mail.ru).

Andrei N. Grachev (Kazan, Russian Federation) – Doctor of Technical Sciences, Professor of the Department of Chemical Technology of Wood of Kazan National Research Technological University (68, Karl Marx Street, Kazan, 420015; e-mail: energolesprom@gmail.com).

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The use of cellulose obtained from soybean shells is relevant because it allows the use of soybean production waste, which facilitates recycling and reduces the negative impact on the environment. The resulting cellulose can be used in the food industry to produce dietary fiber, which is an important component of a healthy diet, or in the cosmetics industry.

Purpose of the work: extract cellulose from the soybean shell and study its functional properties.

For the first time, enzymatic hydrolysis of the soybean shell with proteases was carried out: Protamex, Alcalaze and Flavourzame. Influence of enzyme type on functional properties of soybean processing products was determined.

The functional properties of soybean processing products were studied. The mass fraction of moisture and water-soluble substances of the studied samples was determined by the gravimetric method. Ash content was determined according to GOST 18461-93, wettability - according to GOST 595-79.

Using scanning electron microscopy, the fibrillar structure of soybean processing products, characteristic of cellulose, was revealed. Its elemental composition was controlled by energy dispersive analysis. It has been shown that cellulose obtained from Flavourzame is rich in microelements magnesium, calcium, phosphorus, and potassium. The pulp produced from Protamex contains nitrogen.

It was found that the wettability of all cellulose samples increased by 1.6-1.7 times compared to the soybean shell.

The functional properties of cellulose obtained with Protamex are better compared to samples extracted with other enzyme preparations: compared to soybean shell, the ash content is 1.8 times higher; the proportion of water-soluble substances is 1 % higher.

The results obtained confirm the prospects of using cellulose from soybean hulls as an additive in food or cosmetics.

Keywords: soybean shell, fermentation, wettability, ash content, scanning electron microscopy (SEM), energy dispersive analysis.

Nikita S. Evdokimov (Omsk, Russian Federation) – Ph.D. in Technical Sciences, Associate Professor, Department of «Biotechnology, catering technology and commodity research», Omsk State Technical University (11, Mira av., Omsk, 644050; e-mail: ens17@mail.ru).

Elizaveta S. Sakharova (Omsk, Russian Federation) – Bachelor of direction 19.03.01 “Biotechnology”, Omsk State Technical University (11, Mira av., Omsk, 644050; e-mail: sakharova-elizavetka@mail.ru)

Olga V. Malij (Omsk, Russian Federation) – Undergraduate Student of Direction 19.04.01 “Biotechnology”, Omsk State Technical University (11, Mira av., Omsk, 644050; e-mail: malij_olga@mail.ru).

Evgeniy A. Rogachev (Omsk, Russian Federation) – Ph.D. in Technical Sciences, Associate Professor, Department «Physics», Omsk State Technical University (11, Mira av., Omsk, 644050; e-mail: evg-rogachev@yandex.ru).

Valentina V. Dan'shina (Omsk, Russian Federation) – Ph.D. of Chemical Sciences, Associate Professor, Department «Physics», Omsk State Technical University (11, Mira av., Omsk, 644050; e-mail: danshina_v@mail.ru).

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In recent years, considerable attention has been paid to the development of new materials for use in biosensors, especially in the field of glucose determination. Glucose is one of the most common bioanalysts, and the accuracy and reliability of its measurement is important for the diagnosis and control of diseases associated with metabolic disorders. The focus of modern research in the field of biosensor development is currently aimed at improving the methods of modification of the electrode surface and the use of new materials for the immobilization of enzymes with conductive properties. Nanocomposite materials have proven themselves most clearly in this aspect. In this work, electropolymerized thionine was used as a basis for the formation of hybrid nanocomposite conductive polymers. To improve the conductive ability of poly(thionine), it was used together with thermally expanded graphite and carbon nanotubes. The immobilization of the enzyme on the surface of the material plays an important role in ensuring the stability and high activity of enzymes.

The structure of the resulting polymer was studied by IR spectroscopy. Electrochemical characteristics were studied by cyclic voltammetry. It is shown that from the point of view of both the electron transfer rate to the electrode and the rate of interaction with the active glucose oxidase center, a new nanocomposite based on poly(thionine) and thermally expanded graphite is the most promising. The sensor based on the created nanocomposite material is characterized by a sensitivity of 14.3 ± 0.6 µA ∙ mM–1∙ cm–2, the lower limit of the determined glucose concentrations is 0.06 mM.

Thus, the developed biosensor can be used as an alternative to the standard method of analysis and as a prototype for the creation of sensitive and accurate glucose meters and biosensors for the evaluation of other metabolites.

Keywords: conductive polymer, poly(thionine), printed electrode, carbon nanotubes, thermally expanded graphite, glucose oxidase.

Lyubov S. Kuznetsova (Tula, Russian Federation) – Postgraduate Student of the Department of Chemistry of Tula State University (92, Lenin av., Tula, 300012; e-mail: lslatunina@gmail.com).

Kristina D. Ivanova (Tula, Russian Federation) – Master's Student of the Department of Chemistry of Tula State University (92, Lenin av., Tula, 300012;
e-mail: krictina578@gmail.com).

Vyacheslav A. Arlyapov (Tula, Russian Federation) – Doctor of Technical Sciences, Associate Professor of the Department of Chemistry of Tula State University (92, Lenin av., Tula, 300012; e-mail: v.a.arlyapov@gmail.com).

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Dioctyl terephthalate (DOTP) is an ester of 2-ethylhexanol and terephthalic acid (TPA), widely used as an industrial plasticizer, characterized by high dielectric properties, cold resistance, reduced volatility, and resistance to decomposition. Due to its widespread use, DOTP is a common environmental pollutant. The most environmentally friendly and effective method for recycling phthalates is a biological method based on the ability of bacteria to decompose phthalates, including DOTP and TPA, an intermediate product of bacterial destruction of DOTP.

The ability of the strain Rhodococcus sp. S6, isolated from activated sludge from biological treatment facilities of a chemical enterprise (Perm region), to growth on DOTP and TPA as the only source of carbon and energy, was studied. It was found that strain S6 is capable of utilizing 55.6 % DOTP (initial concentration 0.5 g/l) within 48 hours of cultivation. Strain S6 grew and utilized TPA at concentrations up to 30 g/L. When growing the strain in a medium with 20 g/l TPA, the maximum values of growth parameters were recorded: OD600 = 1.72, specific growth rate of the culture (0.07 h–1). The ability to utilize TPA at concentrations above 10 g/l has not previously been demonstrated for strains of the genus Rhodococcus. Strain Rhodococcus sp. S6 is promising for the development of methods for bioremediation of soils and wastewater contaminated with DOTP and TPA.

Keywords: Rhodococcus, biodegradation, terephthalic acid, dioctyl terephthalate.

Olga V. Yastrebova (Perm, Russian Federation) – Candidate of Biological Sciences, Researcher at the Laboratory of Microbiology of Technogenic Ecosystems of the Institute of Ecology and Genetics of Microorganisms of the Ural Branch of the Russian Academy of Sciences (13, Goleva str., Perm, 614081; e-mail: olyastr@mail.ru).

Elena G. Plotnikova (Perm, Russian Federation) – Doctor of Biological Sciences, Head of the Laboratory of Microbiology of Technogenic Ecosystems of the Institute of Ecology and Genetics of Microorganisms of the Ural Branch of the Russian Academy of Sciences (13, Goleva str., Perm, 614081; e-mail: peg_el@mail.ru).

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In this paper, one of the ways of limiting the spread of the aggressive invasive plant borscht of Sosnovsky Heraculum sosnowskyi Manden, which excludes dangerous contact of the juice of this plant with the human skin. This method is based on injecting 6 % apple cider vinegar in optimal volumes into the stem of the plant before its fruiting. Injection into the hollow part of the stem causes complete necrosis of the ground part of the plant, which has been exposed to food apple cider vinegar, within 48 hours. At the same time, acetation is an exclusively selective process, characteristic only of Sosnovsky hogweed, and does not have the negative environmental effects observed when using glyphosate, imidazolinine, sulfonylurea and other known herbicides. To confirm the exceptional selectivity of injections on hogweed, the work shows that injections of 6 % apple cider vinegar do not act on the hollow stems of the garden wasp Sónchus oleraceus. It is noted that injections of water into the stems of both types of compared plants do not lead to the death of their terrestrial part. Using high-performance liquid chromatography methods, it was shown that in stems after injections of 6% apple cider vinegar, an induced increase in the content of furocoumarins was observed in 48 hours as a response to an irritant dangerous to the plant, the content of xanthotoxin increased by 1.7 times. The proposed method of limiting the spread of borscht Sosnovsky makes it possible to differentially remove the upper part of the plant from natural landscapes without disturbing the growth of neighboring plant species.

Keywords: Sosnovsky's hogweed, apple cider vinegar, injections into stems, necrosis of the ground part of the plant, furocoumarin, liquid chromatography.

Alexander V. Pavlov (Yaroslavl, Russian Federation) – Ph.D. in Technical Sciences, Associate Professor of the Department “Chemical Technology of Organic Coatings”, Yaroslavl State Technical University (88, Moskovsky av., Yaroslavl, 150023), e-mail: pavlovalexaaadr1@gmail.com.

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The paper presents experimental evidence of the existence of a second mass transfer mechanism in metal melts acting simultaneously with diffusion. To this end, several experiments have been conducted, conventionally designated as a "lyophobic wick", using tin and lead melts as a model system, as the most studied in this regard. As a result of the study, it is shown that when a vertical quartz rod is introduced into a container with liquid lead, which is not wetted by both components, the apparent upward diffusion rate of lead increases tenfold, which can only be explained by its additional mass transfer over the surface of the rod. This result corresponds to the previously formulated conclusions about the mechanism of gravitational instability of metallic melts in capillaries, in which the process of partial stratification is also explained by the flow of a monoatomic layer along the interfacial surface between the melt and the lyophobic capillary wall. When creating similar conditions for the surface flow downward, the apparent diffusion rate can be increased even more - by more than two orders of magnitude - which can also be explained only by the appearance of another, more efficient mass transfer mechanism. This mechanism is presumably the surface flow of a heavy component based on the principle of a simple hydraulic siphon localized within a topologically connected, single interfacial surface that unites the volumes of the experimental cell. It is revealed that the narrowing of the transverse perimeter of the interphase flow leads to the appearance of a local increase in the concentration of lead, which is associated with the transition of some of its atoms from the monatomic interphase layer into the melt volume, while lead from the main flow continues to flow down, leading to its accumulation in the lower part of the cell. In general, all the identified effects confirm the existence of a surface flow of the melt components, which should be taken into account when developing the theory of the liquid state and is of interest for practical application.

Keywords: diffusion in liquid metals; lyophobic wick; surface flow; interfacial surface; hydraulic siphon.

Nikolay P. Uglev (Perm, Russian Federation) – Ph.D. in Chemical Sciences, Associate Professor of the Department of Chemical Technologies, Perm National Research Polytechnic University, Perm, Russian Federation (29, Komsomolsky av., Perm, 614990; e-mail: ouglev2014@gmail.com).

Sergei N. Uglev (Perm, Russian Federation) – General Director, “Information Technologies-Volga region” LLC (47, Kuibyshev str., Perm, 614016;
e-mail: suglev@gmail.com).

Elizaveta F. Timerbulatowa (Perm, Russian Federation) – Master of the Department of Chemical Technologies, Perm National Research Polytechnic University, Perm, Russia (29, Komsomolsky av., Perm, 614990; e-mail: liza.timerbulatowa@mail.ru).

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The paper presents the results of investigation of the hydrogen influence to the properties of the corrosion-resistant alloys and non-ferrous metal alloys at room temperature and atmospheric pressure. Well known, that the hydrogenation of metals and alloys is an unavoidable process for the hydrogen presence, however, different types of metals and alloys change their properties differently. For the most alloys, it leads to their embrittlement, but in varying degrees. However, for the some alloys it can lead to its softening. The reasons of alloy's properties changing can be chemical or physical. Thermodynamic calculations of the chemical interactions between alloy compounds and hydrogen (which can lead to the formation of non-metallic compounds inside the metal) have shown that the formation of these compounds can be likely due to carbon, titanium, magnesium and zirconium contents in alloys. Investigation of the hydrogenation process for alloys (which have chemically inert to hydrogen compounds) at room temperature and atmospheric pressure for 1500...1600 hours, have shown that alloy's microhardnes has changed in hydrogenation process for increasing or decreasing. The correlation analysis has showed the presence of a statistically significant positive relationship between the microhardness changing of all alloys in hydrogenation process and their initial microhardness. It was determined, that alloys based on copper and aluminum, and have a microhardness less than 160...170HV, showed softening during hydrogenaton process. Contrariwise, alloys based on iron and titanium, with martensitic and austenitic structures, showed an increase in microhardness during hydrogenaton process. The determined changes of microhardness of alloys in the hydrogenaton process shall be taking into consideration for their using in hydrogen containing environments.

Keywords: hydrogen, alloys, thermodynamic analysis, microhardness, softening, embrittlement, alloy structure, correlation analysis.

Anastasia A. Molokanova (Perm, Russian Federation) – Undergraduate Student of the Department of Chemical Technologies of Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990, e-mail: cool-a-kardas@ya.ru).

Dmitry V. Saulin (Perm, Russian Federation) – Ph.D. in Technical Sciences, Associate Professor of the Department of Chemical Technologies of Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990,
e-mail: sdv_perm@mail.ru).

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Hydrogen Embrittlement Mechanism in Fatigue Behavior of Austenitic and Martensitic Stainless Steels. Metals. 2018. vol. 8(5). pp. 339. DOI: 10.3390/ met8050339

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The widespread use of quartz glass determines the constant interest in improving the technology of its production. Quartz glasses obtained by the sol-gel method are in many respects not inferior to other types of quartz glasses, and in some even superior to them. Despite the apparent simplicity of the sol-gel synthesis technology for quartz glass, it is a complex, multi-stage, catalytic process occurring in a heterogeneous system. Consequently, the use of in-line analytical methods to control the technological processes of sol-gel synthesis will make it possible to control the progress of the reaction with accurate prediction of the end of the process and the properties of the final product.

This work demonstrates a fiber-optic refractometer that makes it possible to determine the change in the refractive index from the difference in back reflections from a Bragg grating and Fresnel reflections from the end of an optical fiber. Thus, the so-called «differential scheme» of measurement was implemented.

Using the proposed fiber-optic refractometer, studies of the acid hydrolysis reaction of TEOS in an aqueous-alcoholic medium were carried out. The molar ratio of the starting components TEOS:EtOH:H2O:HCl (1:5,79:11,06:0,0012) and the conditions for the hydrolysis of TEOS correlate with those presented in the classical study. The resulting kinetic curve is characterized by a linear rise leading to a flat section. The linear section of the kinetic curve has a slope corresponding to the reaction of the pseudo-first order of the hydrolysis of TEOS and close to the lines of change in the concentration of TEOS according to the model presented in the classical study of Fife. Thus, the experimental results obtained in this work are in good agreement with the known literature data.

Keywords: quartz glass, sol-gel synthesis, hydrolysis, condensation, tetraethoxysilane, silicon dioxide, refractometer, kinetics, back reflections, refractive index, FBG.

Liudmila A. Zhikina (Perm, Russian Federation) – Head of Laboratory at Perm Scientific-Industrial Instrument Making Company (106, 25th Oktyabrya Str., Perm, 614990; e-mail: lusyzh@gmail.com).

Alexander M. Minkin (Perm, Russian Federation) – Ph.D. of Technical Sciences, Senior Lecturer, Department of Physical Chemistry, Perm State National Research University (15, Bukirev str., Perm, 614990; e-mail: minkin.90@gmail.com.

Alexander N. Vasyanin (Perm, Russian Federation) – Ph.D. of Chemical Sciences, Associate Professor, Department of Physical Chemistry, Perm State National Research University (15, Bukirev str., Perm, 614990; e-mail: avasyanin@psu.ru).

Marina T. Krauzina (Perm, Russian Federation) – Ph.D. in Physics and Mathematics, Senior Lecturer, Department of General Physics, Perm State National Research University (15, Bukirev str., Perm, 614990; e-mail: krauzina@psu.ru).

Natalia A. Medvedeva (Perm, Russian Federation) – Ph.D. of Chemical Sciences, Head of the Department of Physical Chemistry, Head of Laboratories of the Competence Center of the National Technological Initiative «Photonics», Perm State National Research University (15, Bukirev str., Perm, 614990; e-mail: nata-kladova@yandex.ru).

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The ability of manganese dioxide to exhibit a catalytic effect allows the production of catalysts based on it. Today, manganese-containing catalysts have found wide application in various fields: catalytic purification of air from oxygen-containing impurities; purification of natural waters from iron; gas purification from nitrogen and carbon oxides and other areas.

Traditional methods for producing manganese dioxide are chemical and electrochemical deposition.

However, recently there have been plans to develop technologies towards the use of new modern technological methods that make it possible to obtain active modification manganese dioxide with more pronounced catalytic properties.

Due to the widespread use of manganese catalysts, research devoted to the search for new and more effective methods for the synthesis of manganese-based catalysts is becoming increasingly important. Based on scientific and patent literature data, the main ways of developing the technology of manganese-containing catalysts were identified: the development of fundamentally new methods for producing manganese catalysts, the development and improvement of a method for molding granules, adjusting the complex composition of the catalyst and its modifications, increasing catalytic activity and searching for new forms and carriers of the active component.

Among a number of areas for improvement, one can single out the direction of modifying a catalyst based on manganese dioxide with various components in the form of metal oxides. Depending on the area of application, various compounds of metals from transition groups of the periodic table can impart activity to the catalyst.

The most promising developments in the field of producing catalysts based on manganese dioxide have been identified and new areas of application of catalytic compositions have been shown.

Keywords: manganese-containing catalysts; technology improvement; manganese dioxide; catalytic purification.

Asiia R. Kobeleva (Perm, Russian Federation) – Ph.D. in Technical Sciences, Associate Professor of the Department of Chemical Technologies, Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990,
e-mail: kobelevaasya@mail.ru).

Evgenia O. Kuzina (Perm, Russian Federation) – Senior lecturer, Department of Chemical Technologies, Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990; e-mail: zena322myname@mail.ru).

Anastasia P. Zhukovskaia (Perm, Russian Federation) – Student, Perm National Research Polytechnic University (29, Komsomolsky av., Perm, 614990,
e-mail: nastya59rf@gmail.com).

1. Inok I. Vang, Lifan Lin, Uill'yam L. Bauden Sposob polucheniya gamma dioksida marganca, gibridnyj material, soderzhashchij gamma MnO2, elektrohimicheskaya yachejka [Method for obtaining gamma manganese dioxide, hybrid material containing gamma MnO2, electrochemical cell]. Patent Rossiiskaya Federaciya no. 2118292 (1998);
2. Egorova A.A., T.M. Bushkova, I.V. Kolesnik, A.D. YAprynceva, S.YU. Kotcova, A.E. Baranchikov Selektivnyj sintez polimorfnyh modifikacij dioksida marganca gidrotermal'noj obrabotkoj vodnyh rastvorov KMnO4 [Selective synthesis of polymorphic modifications of manganese dioxide by hydrothermal treatment of KMnO4 aqueous solutions]. ZHurnal neorganicheskoj himii, 2021, Vol. 66, No. 2, pp. 141–148;
3. SHaripov H.B. A.D. YApryncev, A.E. Baranchikov, i dr. Sintez dioksida marganca metodom gomogennogo gidroliza v prisutstvii melamina [Synthesis of manganese dioxide by homogeneous hydrolysis in the presence of melamine]. ZHurnal neorganicheskoj himii, 2017, Vol. 62, No. 2, pp. 143–154;
4. T. L. Rakitskaya, A. S. Truba, A. V. Nagaevskaya Sintez i kataliticheskaya aktivnost' dispersnih oksidov marganca(ІV) v reakcii razlozheniya ozona [Synthesis and catalytic activity of dispersed manganese (IV) oxides in the ozone decomposition reaction]. Vіsnik Odes'kogo nacіonal'nogo unіversitetu. Hіmіya. 2017. Vol. 22, No. 4(64). pp. 6-14
5. SHevchenko A.O., SHelyapin I.P., Vasil'ev N.P. , [i dr.]. Sposob polucheniya katalizatora dlya ochistki gazov ot oksida azota [A method for obtaining a catalyst for purifying gases from nitrogen oxide]. Patent Rossiiskaya Federaciya no. 2147461 (2000);
6. Solov'ev S.N., Muhin V.M., Sotnikova N.I. Sposob polucheniya katalizatora okisleniya oksida ugleroda [Method for obtaining a carbon monoxide oxidation catalyst]. Patent Rossiiskaya Federaciya no. 2530890 (2014);
7. Gubajdulina T.A., Kaminskaya O.V., Apkar'yan A.S. Fil'truyushchij material dlya ochistki vody ot zheleza, marganca i serovodoroda i sposob ego polucheniya [Filter material for water purification from iron, manganese and hydrogen sulfide and the method of its preparation]. Patent Rossiiskaya Federaciya no. 2447922 (2012);
8. Voropaeva L.A. Katalizator okisleniya oksida ugleroda [Carbon monoxide oxidation catalyst]. Patent Rossiiskaya Federaciya no. 2203732 (2003);
9. Anikin S.K., Vasil'ev N.P., Kireev S.G., [i dr.]. Sposob polucheniya katalizatora okisleniya oksida ugleroda [Method for obtaining a carbon monoxide oxidation catalyst]. Patent Rossiiskaya Federaciya no. 2083279 (1997);
10. Nimejer Dirk, SHyoneborn Markos, Harmening Tomas, Rol'fs Zyonke Kompoziciya na osnove oksida alyuminiya, soderzhashchaya oksid marganca, cposob ee polucheniya i ee primenenie [Composition based on aluminum oxide containing manganese oxide, method of its preparation and its application]. Patent Rossiiskaya Federaciya no. 2019115895 (2018);
11. H. L. N'yan, M. V. Donina, O. V. YArovaya [i dr.] Harakteristiki i kataliticheskaya aktivnost' keramicheskih membran s nanesyonnym sloem nanochastic MnO2 [Characteristics and catalytic activity of ceramic membranes with a deposited layer of MnO2 nanoparticles]. Uspekhi v himii i himicheskoj tekhnologii. 2019. Vol. 33, No. 3(213). pp. 95-97;
12. R. A. Ahmed'yanova, E. A. Vasil'eva, R. R. Muhamedzyanov [i dr.] Fiziko-himicheskie harakteristiki geterogennyh marganec-oksidnyh katalizatorov okisleniya uglevodorodov, poluchennyh v sverhkriticheskoj vode [Physico-chemical characteristics of heterogeneous manganese-oxide catalysts for the oxidation of hydrocarbons obtained in supercritical water]. Vestnik Tekhnologicheskogo universiteta. 2023.Vol. 26, No. 5. pp. 10-14;
13. Bel'skih L.I., Gorlenko L.E., Emel'yanova G.I. Katalizator ochistki vozduha ot kislorodsoderzhashchih primesej i sposob ego prigotovleniya [Catalyst for air purification from oxygen–containing impurities and method of its preparation]. Patent Rossiiskaya Federaciya no. 2052287 (1996);
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The purpose of the article is to develop new methods for diagnosing the properties of a lubricant in the field in the absence of time for long-term laboratory experiments, as well as the use of the methods under consideration without expensive equipment to prevent premature replacement of the lubricant, or vice versa, its replacement only after it has lost the required tribotechnical properties. Viscosity is accepted as the main determining parameter of the state of the lubricant. When obtaining a specific real picture, a production case of the influence of elevated temperatures on the state of oil viscosity is considered using the example of a pump for transporting liquefied hydrocarbons. The paper considers four lubricant samples, three of which worked under different conditions, and the fourth acts as a reference for comparison. Lubrication analysis was performed using several advanced droplet methods. The first method was to obtain an oil spot on a horizontal sheet of office paper and measure its size at specified time intervals. It was assumed that with a decrease or increase in the viscosity of the oil, the spread of the oil spot on paper would change dramatically. However, as a result of a series of experiments, the difference between working oils and fresh ones turned out to be insignificant and depended on many factors, one of which is the ambient temperature. After revealing such a significant effect of temperature on the viscosity index, an experiment was carried out in which the degree of influence of the temperature of the lubricant on the viscosity was determined and a more correct picture was obtained when analyzing the lubricant. The next method for monitoring the condition of the lubricant was to apply the lubricant to a sheet of paper located at certain angles, and the distance traveled by the oil drop was measured for the specified time. This method showed unexpected results and should be examined in more detail by changing the various input parameters.

Keywords: industrial oil, kinematic viscosity, tribological properties of oils, chromatographic method, visual control, viscometer, oil spot.

Boris I. Starodubcev (Perm, Russian Federation) – Ph.D. in Technical Sciences, Associate Professor of the Department of Equipment and Automation of Chemical Production, Perm National Research Polytechnic University (29, Kom­somolsky av., Perm, 614990, e-mail: BISTARODUBCEV@pstu.ru).

Vladimir A. Sidorov (Donetsk, DPR, Russian Federation) – Associate Professor, Doctor of Engineering Sciences, Professor of the Department "Mechanical Equipment of Ferrous Metallurgy Plants" named after prof. Sedusha V.Ya. Donetsk National Technical University (58, Artem str., Donetsk, 83001,
e-mail: sidorov_va58@mail.ru).

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