Кафедра "Фізична хімія"

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/1402

Офіційний сайт кафедри http://web.kpi.kharkov.ua/fchem

Кафедра "Фізична хімія" заснована в 1926 році професором Олександром Миколайовичом Щукарьовим. Свої витоки вона веде від 1918 року, коли кафедра хімії розділилася на кафедри неорганічної, органічної, аналітичної і фізичної хімії.

У різні роки нею керували професори Ілля Іванович Стрєлков, Сергій Степанович Уразовський, Аркадій Юхимович Луцький, Володимир Мойсейович Кошкін. Від 2012 року кафедру очолює доктор технічних наук, професор Микола Дмитрович Сахненко, академік АН Вищої освіти України.

Кафедра входить до складу Навчально-наукового інституту хімічних технологій та інженерії Національного технічного університету "Харківський політехнічний інститут". Наукова школа кафедри включає понад 90 кандидатів і докторів наук.

У складі науково-педагогічного колективу кафедри працюють: 2 доктора та 2 кандидата технічних наук, 1 кандидат хімічних наук; 1 співробітник має звання професора, 2 – доцента, 1 – старшого наукового співробітника, 1 – старшого дослідника.

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2018 - 20203

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Автор: search.filters.author.Nekrasov, P. O.Містить файли: Так

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  • Ескіз
    Документ
    Optimizing the parameters of the production process of fat systems with a minimum content of trans-isomers
    (Український державний хіміко-технологічний університет, 2020) Nekrasov, P. O.; Gudz, O. M.; Nekrasov, O. P.; Berezka, T. O.
    Currently, the vast majority of solid fats, which are used as formula components of food products, are produced in Ukraine by partial hydrogenation. This method of fats modification leads to the formation of a significant amount of trans-isomers of fatty acids, which negatively affects the human body. It is known that the increased content of these isomers in the composition of fat products results in an increased risk of developing cardiovascular and metabolic diseases. In particular, the action of high-density lipoproteins is blocked, the deposition of cholesterol plaques on the walls of human blood vessels is initiated, and the development of atherosclerosis is provoked. We suggest resolving this problem by using interesterification of fats under the action of lipases, which has some advantages as compared with traditional technology. For instance, alkaline agents will not be used for catalysis, the reaction products will not be contaminated with catalysts, soaps will not be formed as by-products, the temperature of the process will be almost halved, and the organization of production will be less complicated and cheaper. The purpose of the work was to determine the rational parameters of the interesterification reaction aimed at the synthesis of fat systems with a minimum content of trans-isomers. The research objective was achieved by using the response surface methodology. The kinetics of reaction was studied by pulsed nuclear magnetic resonance. The processing and analysis of experimental data was performed by means of the Statistica 10 package. As a result of investigations, a mathematical model was developed that allows predicting the degree of conversion of starting materials into reaction products based on the data on the conditions of the interesterification process. Rational values of the main parameters for the synthesis of fatty systems with a minimum content of trans-isomers of fatty acids were specified. The obtained results can serve as a scientific basis for the development of technology for the production of fat systems with improved quality and safety characteristics.
  • Ескіз
    Документ
    Optimization of the composition of fat systems of new generation
    (Технологічний центр, 2019) Nekrasov, P. O. ; Gudz, O.; Nekrasov, O.; Berezka, T. O.
    Fats are an integral part of human nutrition. The increased content of trans-isomers in their composition causes a number of cardiovascular diseases and metabolic disorders. A promising approach to solving the problem of minimizing the content of trans- isomers of fatty acid in the composition of food products is the creation of a new generation of fat systems – the oleogel, which is the subject of the presented research. As the dispersion medium of the oleogel, high-oleic sunflower oil is used, in contrast to the oil of traditional varieties, it is possible to obtain systems with enhanced oxidation resistance. The dispersed phase of these fat systems is beeswax, tripalmitin and monoacylglycerols. The choice of a complex of these components is based on their properties to create in oleogels a three-dimensional structure with desired thermomechanical characteristics. At present, there is not enough information about the dependence of the main characteristics of the oleogel on the ratio of ingredients of dispersed phase. In particular, one of the most problematic places in the oleogel technology is its thermal stability, which significantly affects the parameters of production, transportation, as well as storage conditions and periods. To solve this problem, the methodology of the response surface is used in the work. The determination of the unknown values of the parameter vector is carried out by applying regression analysis algorithms. The minimization of the deviation functional is performed by finding the appropriate combinations of experimental predictor series. As a result of research, a mathematical model is developed, which allows, based on data on the component composition of the oleogel, to predict its thermal stability. Reasonably rational mass fractions of the components of the dispersed phase of the oleogel: the content of beeswax is 3.27 wt. %; content of tripalmitin is 3.07 wt. % and the content of monoacylglycerol is 4.70 wt. %, at which the maximum value of the response function is reached. The results will serve as a scientific basis for the development of technological parameters of the industrial production of fat systems of the new generation, the conditions and terms of their storage and transportation.
  • Ескіз
    Документ
    Kinetics and thermodynamics of biocatalytic glycerolysis of triacylglycerols enriched with omega-3 polyunsaturated fatty acids
    (Украинский государственный химико-технологический университет, 2018) Nekrasov, P. O.; Piven, Olena Mykolayivna ; Nekrasov, O. P.; Gudz, O. M.; Kryvonis, N. O.
    The enrichment of fats with omega-3 polyunsaturated acids increases the nutritive value of fats and makes them more health promoting by boosting the immune system and reducing blood coagulability, the level of neutral lipids and the risk of coronary heart disease and atherosclerosis. That is why it is important to develop scientific basis of the synthesis of these lipid systems. There have been created the mathematical model of kinetics of enzymatic glycerolysis of triacylglycerols enriched with omega-3 polyunsaturated fatty acids, enabling quantitative and qualitative assessment of the reaction composition. For the mathematical modeling of the process, a system of nonlinear differential equations has been created which describes the change in the content of the resulting substrates and reaction products through time. To determine acylglycerol composition of the reaction systems, the high temperature gas-liquid chromatography method was used. The simulation was performed using Mathcad 15 environment via the identification of the parameters of the model by means of a random multivariable search algorithm being called a method of complexes, in the course of which the errors between experimental and model data were minimized. The Runge–Kutta method with a variable step of the fourth order of accuracy was used as a numerical procedure for differential equations modelling. As a result of the calculations, the numerical values of the constants of direct and reverse reactions rates and the corresponding equilibrium constants were determined. Based on the received constants of homogeneous substrates mixtures the values of thermodynamic parameters and activation energies of the studied process have been calculated. The conclusions have been drawn about the contribution of each reaction, occurring during biocatalytic glycerolysis of triacylglycerols, to the process under consideration.