Kononenko, P. N.

Vassilyeva, Yuliya Zakharovna

Electronic archive of Tomsk Polytechnic University

Том 2 XXII Международная конференция «Химия и химическая технология в XXI веке»232ANALYSIS OF POWDER SYNTHESIZED IN Mo–C–N SYSTEM BY SCANNING ELECTRON MICROSCOPYYu.Z. Vassilyeva, P.N. KononenkoSupervisor – Ph.D., Researcher A.Ya. PakLinguist – Ph.D., Researcher A.Ya. PakNational Research Tomsk Polytechnic University 634050, Russia, Tomsk, 30 Lenin Avenue, yzv1@tpu.ruHydrogen is a sustainable, renewable, and envi-ronmentally friendly energy source. As known, one of the possible effective methods for its producing is electrochemical water splitting [1–2]. However, this method requires highly active electrocatalysts. Currently, platinum is the most promising catalyst, but it has high cost and is limited in resources. The materials of the molybdenum-carbon-nitrogen sys-tem can become substitutes for such a metal, be-cause they have physical and chemical properties: electrical conductivity, chemical stability and high catalytic activity [3–4].One of the methods for obtaining materials of the molybdenum-carbon-nitrogen system is the method of synthesis in a DC arc plasma under at-mospheric conditions [5]. This method is based on the generation of an arc discharge between graphite electrodes, as a result of the combustion of which a protective environment of CO and CO2 is formed, which shields the synthesis zone from oxidation by oxygen.The aim of the paper is to analyze the particles morphology of the synthesized powder material obtained by a vacuum-free electric arc method in molybdenum-carbon-nitrogen system, as well as to study its elemental composition.Experimental studies were carried out on an electric arc reactor with a horizontal system of electrodes made in the form of graphite rods. The initial reagents were a mixture of molybde-num, graphite and melamine powders in the ratio Mo : C : C3N6H6 = 2 : 1 : 1. The initial mixture was evenly distributed on the bottom of a graphite cru-cible, in the cavity of which an arc discharge was initiated. The distance from the discharge initia-tion zone to the location of the initial reagents was 9 mm. The synthesis took place at an amperage of 200 A for ~ 10 seconds.The study of particle morphology and ele-mental composition was perfomed using a Tescan VEGA 3 SBU scanning electron microscope (Czech Republic). The study was carried out without any preliminary preparation of the initial material: the powder was applied to a special tape.Figure 1 shows SEM images of the obtained particles in the Backscattered-Electron (BSE) and Secondary Electrons (SE) modes. As can be seen, the sample contains accumulations of newly formed particles ranging in size from 10 to 70 μm, with sin-gle nanosized crystallites. According to the analysis of the elemental composition, the main elements are C (~ 36.79 %), Mo (~ 53.05 %) and O (~ 6.37 %). Fig. 1.  SEM images of the sample using (a) SE mode and (b) BSE mode Секция 7.  Химия и химическая технология на иностранном языке (английский)233Also, impurities of S, Ti, W, Pb, Bi, Pd are found, the total mass of which does not exceed ~ 3.5 % on average, which indicates a fairly high purity of the resulting product.Thus, the paper shows the results of the analy-sis of powder materials of the molybdenum, carbon, nitrogen system by scanning electron microscopy.The reported study was funded by RFBR ac-cording to the research project № 20-38-90088.References1.  Huang Yi., Ge J., Hu J. et al. // Advanced Ener-gy Materials, 2018. – V. 8 (6). – P. 1701601. 2.  Chi J.-Q., Gao W.-K., Lin J.-H. et al. // Journal of Colloid and Interface Science, 2018. – V. 513. – P. 151–160.3.  Ang  H.,  Tan  H.T.,  Zhang  Yu.  et  al.  //  Small., 2015. – V. 11 (47). – P. 6278–6284.4.  Wang Sh., Wang J., Zhu M. et al. // Journal of the American Chemical Society, 2015. – V. 137 (50). – P. 15753–15759.5.  Васильева  Ю.З.,  Кононенко  П.Н.,  Пак  А.Я. // Наука. Технологии. Инновации  // Сборник научных трудов в 9 ч. / под ред. Гадюкиной А.В.  –  Новосибирск:  Изд-во  НГТУ,  2020.  – Часть 5. – С. 3–6. HYDROCRACKING FEEDSTOCK COMPOSITION AND PROPERTIES INVESTIGATION FOR HYDROCARBON GROUP ANALYSISE.K. Vymyatnin, A.A. OreshinaAcademic Advisor – D.Eng.Sc., Professor E.D. IvanchinaNational Research Tomsk Polytechnic University 634050, Russia, Tomsk, 30, Lenin Avenue, EKVT70@gmail.com, sasha.oreshina.94@mail.ruThe basic principle of hydrocracking is the transformation of large high boiling hydrocarbon molecules in the presence of hydrogen into smaller molecules with a lower boiling point. This transfor-mation occurs due to the breaking of carbon-carbon bonds or the removal of heteroatoms connecting the two unbonded parts of the hydrocarbon. The feed-stock of hydrocracking is usually vacuum gas oil, and primary products of the process are more valu-able and light motor fuels and their components.The quality of the products varies greatly de-pending on the process conditions and the feedstock composition. The product yield decreases over time due to catalyst deactivation. For these reasons, con-stant feedstock and products quality monitoring as well as catalyst activity monitoring are very import-ant. Laboratory analysis of feedstock, products and catalyst samples is time-consuming and cannot pro-vide real-time control. In this case, it is most expedi-ent to apply a predictive model of the hydrocracking process, developed by the mathematical modeling based on the feedstock and products composition data. The predictive model is based on actual opera-tional data of the hydrocracking unit and, therefore, describes the actual process conditions, which al-lows high level quality control of the products. The aim of this work is to obtain data on the refractive indices (RI) of feedstock and products of hydroc-racking process to enhance the predictive model.RI of hydrocarbons makes it possible to es-timate their structure, as well as their mixtures composition, since for a chemical compound at a certain temperature it is constant, and for mixtures it is additive [1]. The RI of hydrocarbons or petro-leum products depends on the compounds chemical structure and increasing in the following order: al-kanes < alkenes < alkylcyclopentanes < alkylcyclo-hexanes < alkylbenzenes < alkylnaphthalenes [1]. The relationship between density and RI is linear. RI of the hydrocarbon increases with density in-creasing. Different hydrocarbon groups have differ-ent dependency factor of RI on molecular weight. The molecular weight has the greatest influence on the RI of paraffinic hydrocarbons, and increases with chain lengthening. Alkyl aromatic hydrocar-bons are an exception. The RI of this hydrocarbons group decreases with lengthening of the side chains and an increase in their amount [1]. It is possible to calculate the structure-group composition of oil fractions, knowing the RI in combination with den-sity value and molecular weight. Therefore, the val-ues of these features play a key role in development of mathematical model of vacuum gas oil hydroc-racking process.

Analysis of powder synthesized in Mo-c-n system by scanning electron microscopy

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Analysis of powder synthesized in Mo-c-n system by scanning electron microscopy

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