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Making a brighter presentation and improving assimilation of educational material with the help of the case method allows activating the mental, exploratory and creative abilities of students to optimize the process of assimilation of information. The combination of this method with others allows making future specialists to independently find ways to solve problems. This results in the assimilation of professionally significant special knowledge. The aim of the study was to determine the features of the application of the case method in the educational process in preparing students for future professional activities, identifying sources, structural elements and filling professional cases. The study involved the survey method and further testing to identify indicators of significance at the summative and control stage of the experiment. Methods used: diagnostic programme to study the level of educational activities by Riepkina, Zaika; assessment of the level of control and self-assessment actions; statistical and mathematical interpretation of empirical data with subsequent functional analysis of the research results. The study showed the high efficiency of the case method in the educational environment of higher educational institutions (HEIs). The indicator of students’ self-presentation after the application of the case method has changed significantly. This was reflected in an increased high level to 35.5%, a decreased medium level to 38%, and a slight increase in all levels in the experimental group students. Positive dynamics was revealed on all criteria for diagnosing the effectiveness of the case method in teaching: a decreased percentage of students with negative and relatively low markers and a corresponding increase in the percentage of students with positive markers of knowledge and learning the material. Further research can deal with development and implementation of case systems in view of certain majors, taking into account future professional activities.

As a result of oil hydration, waste is formed – phosphatide concentrate, which is a multicomponent system. Valuable components of the concentrate are vegetable oil and phosphatides, the separation of which is an urgent task for the industry. The process of treatment of sunflower phosphatide concentrate with citric acid (hydration) in order to more completely convert non-hydrated forms of phosphatides into hydrated ones and separate the oil from the concentrate was studied. A feature of the work is the study of the dependence of the yield and mass fraction of moisture in the extracted oil on the hydration process parameters. A sample of phosphatide concentrate with non-standard quality indicators according to SOU 15.4-37-212:2004 (CAS 3436-44-0) was studied: the mass fraction of moisture and volatile substances was 4.0 %, the mass fraction of phosphatides was 37.0 %. The concentrate was treated with citric acid solution at a temperature of 45 °C (10 % solution). Rational conditions for concentrate treatment were determined: duration (25 min) and citric acid concentration in relation to the mass of phosphatide concentrate (25 %). Under these conditions, the oil yield was 76.1 %, the mass fraction of moisture in the oil was 18.6 %. The indicators characterizing the suitability of the oil for consumption and its safety for the body are within the limits (acid value 3.7 mg KOH/g, peroxide value 5.1 ½ O mmol/kg) for the first-grade unrefined unwinterized sunflower oil according to DSTU 4492. Such oil can be used for refining, fatty acids and biodiesel production, and after additional purification – for processing into food products. The results of the study make it possible to use resources rationally and predict the yield and quality of the oil isolated from the phosphatide concentrate. The resulting oil can be an affordable raw material for various industries.

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The process of sodium glyceroxide obtaining by the reaction of glycerol and sodium hydroxide in the form of an aqueous solution was investigated. Glycerol salts (metal glyceroxides) are important components in the synthesis of many compounds. Glyceroxides are used in the chemical industry, construction, medical practice, etc. Glyceroxides of alkali metals are used in the production of modified fats and biodiesel fuel. P.a.-grade glycerol (CAS Number 56-81-5) was used with a mass fraction of the main substance of 99.5 %. The parameters of sodium hydroxide (CAS Number 1310-73-2) were studied: the mass fraction of the main substance is 98.0 %, the mass fraction of sodium carbonate is 0.5%. Rational conditions for sodium glyceroxide obtaining were determined: temperature (145 °C) and concentration of sodium hydroxide solution (65 %). Under these conditions, the mass fraction of the main substance in the product was 80 %. The melting point (72 °C) and mass fraction of moisture (0.3 %) in sodium glyceroxide were determined. The catalytic activity of the product in the process of transesterification of palm olein was tested. The increase in the melting point of palm olein was 15 °C. Under similar conditions of using potassium glyceroxide with a mass fraction of the main substance of 75.77 %, the increase in the melting point is 12.1 °C. This indicates an increase in the efficiency of the transesterification process using sodium glyceroxide obtained by the developed technology. The research results make it possible to produce sodium glyceroxide under rational conditions with a high mass fraction of the main substance at enterprises that use metal glyceroxides as a production component or commercial product. The determined rational conditions will make it possible to effectively use the company's resources and predict the quality of the final product