Thesis for degree of Candidate of Technical Sciences in the speciality 05.17.07 – “Chemical technology of fuels and lubricants”. National Aviation University of the Ministry of Education and Science of Ukraine, Kyiv, 2021.
The thesis is devoted to the improvement of the technology of oxygen-сontaining additives to gasoline and diesel fuel, which allow to improve the operational and ecological characteristics of blended fuels.
It has been investigated ethyl alcohol absolutization, natural triglycerides and their transesterified forms. In the first stage, urea and thiourea were used to refine gasoline and diesel fuel, respectively, and to enrich gasoline with isoparaffins extracted from diesel fuel and diesel fuel with paraffins extracted from gasoline. This made it possible to increase the octane and cetane numbers of gasoline and diesel.
Absolute ethyl alcohol should be added to prevent stratification of motor fuels. Using mass spectrometric studies, IR spectral and chromatographic analysis, it was shown that the absolutization of ethyl alcohol with calcined calcium oxide and additional dehumidifier filled with calcium chloride promotes the formation of impurities of diethyl ether. Studing composite fuels based on absolute ethyl alcohol, which contains an diethyl ether, it was found that it improves both physicochemical properties, in particular the stability of gasoline - ethanol fuels, and the performance properties of such fuels.
Natural triglycerides of vegetable oils and their transesterified forms were investigated as essential oxygen-containing additives to diesel fuel. Using express analyzers the cetane number and freezing point of composite fuels based on diesel and 15 types of vegetable oils were investigated. It was found that the addition of even small amounts of vegetable oils t increases he cetane number of diesel fuel from 47 to 55-60 units. However, vegetable oils also increase the freezing point of diesel, so it is recommended to use them for summer fuels.
The physicochemical and operational properties of natural triglycerides of vegetable oils, in particular rapeseed oil, were modified by transesterification with absolute ethyl alcohol using a nonionic emulsifier neonol- 9. Using mass spectrometric and gas chromatographic analysis found that synthesized biodiesel consist of fatty acids ethyl esther and ethyl ethers of glycerol. Blended fuels based on diesel and synthesized biodiesel have been studied. It is established that the synthesized product meets DSTU 7178:2010. It has beem proposed an improved technological scheme of rapeseed oil transesterification, wastewater treatment generated during biodiesel washing and a device for processing sludge waste into a granular product, which can be used as a technological additive in the construction and oil industries.
Key words: absolute ethanol, diethyl ether, vegetable oils, transesterification, biodiesel, composite fuel, octane number, cetane number.
