The thesis for the degree of candidate of technical sciences, speciality 05.17.07 - Chemical technology of fuel and lubricants. National aviation university, Kyiv, 2019.
The thesis is dedicated to creating of ethanol fuel with improved performance and environmental properties.
One of the ways to create environmentally friendly fuels of non-petroleum origin can be the development of compound ethanol fuel formulations. Considering the unsatisfactory lubricating properties of ethanol fuels, as well as corrosivity, high heat of evaporation, the introduction of polyfunctional additives to the composition of the fuel is proposed. As the latter, the product was used to synthesize nanocarbon material obtained by the method of electric arc discharge in propane-butane medium at atmospheric pressure, a pulse voltage at the generator output of 6–10 kV and a pulse frequency of the original voltage from 1 to 100 kHz. Using TEM, SEM, AFM, Raman spectroscopy, and X-ray phase analysis of synthesized carbon materials, it has been proved that they belong to spherical nanomaterials with a predominant particle size of 6–100 nm, which contain onion-like carbon nanoclusters). Brominated nanoparticles are used as additives.
It has been established that to improve the operational and environmental characteristics of ethanol fuel, it is sufficient to introduce low concentrations (10–3– 10–2 wt.%) Into the synthesized brominated nanoparticles. The concept of the formation of solvate formations in the organic medium — domains whose size, determined by the photon correlation laser spectroscopy method, varies from 21 to 1000 nm depending on the chemical nature of the solvent, is proposed and substantiated.
For ethanol, the size of such formations was ~ 400 nm, which significantly exceeds the size of the individual additive particles. It is shown that the change in the microheterogeneous structure of fuels affects the change in its physicochemical, operational and environmental characteristics: the dielectric constant and hydrophobicity of the medium decrease, the pressure of saturated vapors increases, which improves the starting properties of the fuel; hydrophobization of the environment contributes to reducing the corrosion properties of ethanol fuel by 1, as a result of which additional introduction of a corrosion inhibitor is not required; the carrying capacity of the fuel in the presence of brominated nanoparticles increases by 1.5 times compared with the base fuel with a corresponding decrease in damage to the metal surface of friction pairs.
During the comparative bench tests it was revealed that the developed composite fuel exceeds the A-95 gasoline in terms of energy and environmental performance, namely: the values of the maximum torque (by 4%) and the effective efficiency (by 20%) increase; the indicator of specific effective heat consumption decreases by 17%; the amount of emissions is reduced: carbon monoxide - by five times, emissions of unburned hydrocarbons - by two times, emissions of nitrogen oxides - by 10 times in comparison with motor gasoline A-95.
Keywords: ethanol fuel, carbon nanoscale spheroidal clusters, physico-chemical, performance and ecological properties of the fuel.