Investigation into the Impact of the Composition of Ethanol Fuel Deposit Control Additives on Their Effectiveness

Abstract

An increasing percentage of ethanol in fuel leads to significant changes in polarity and solubility, which makes conventional gasoline deposit control additives (DCAs) difficult to dissolve in ethanol fuels, resulting in the formation of deposits on engine elements. Critical areas of deposit formation in an engine are constituted by inlet valves, combustion chambers, and fuel injectors. As a consequence, operational parameters of the engine are disturbed to a large extent by the total effect of the deposits. To prevent the aforementioned phenomena, in the operation of engines fueled with ethanol-containing blends, it is necessary to use specifically prepared DCAs. The paper briefly presents a process of development of DCAs dedicated to high-ethanol fuels. Each of the prepared DCA formulations contained a substance having detergent-emulsifying properties (referred to in the text as DEM), a carrier oil, and a solvent. The composition and ratios of components used in the DCA, by testing their effectiveness in engine deposit formation, are verified. A motor station and a test procedure developed for this purpose were used. In search of alternative solutions to conventional polyisobutyleneamines (PIBA) and polyetheramines (PEA) surfactants, which have good solubility in hydrocarbons but not in ethanol, a substance with a benzoxazine structure and a Mannich base were synthesized. Their chemical structures were confirmed by nuclear magnetic resonance (NMR) DCAs were developed, and the effectiveness of their action was verified. Moreover, attention was paid to the dosage level of the DEM and the carrier oil in the DCA. Finally, it was confirmed in the studies carried out that DCAs used for improvement of conventional hydrocarbon engine gasolines are not efficient enough when used in E85 fuels. In the case of the latter, DCAs that have been specifically developed for such fuels should be used, because they have a different chemical structure, and are soluble in the ethanol-gasoline mixture in any ratio of both components.

Critical review on recent progress of ethanol fuelled flex‐fuel engine characteristics

“…Also, increasing the ethanol proportion in fuel blends changes the solubility and polarity, leading to a negative effect on dissolving the conventional DCAs with ethanol blends in FFV and resulting in deposit formation higher than gasoline 164 . In modern days, benzoxazine and mannich structure‐based DCAs are used in FFV to overcome solubility with higher ethanol blends and it shows a more significant reduction of deposits on the engine components 186 …”

“…164 In modern days, benzoxazine and mannich structure-based DCAs are used in FFV to overcome solubility with higher ethanol blends and it shows a more significant reduction of deposits on the engine components. 186…”

Experimental Investigation on Knock Characteristics from Pre-Chamber Gas Engine Fueled by Hydrogen

“…Studies of knock combustion often focus on its onset, which is determined by the chemical kinetics governing auto-ignition as pressure and temperature rise in the unburned air-fuel mixture during the engine cycle. Complex chemical, such as the composition of the fuel mixture [1,2], and physical relationships influence the formation of this phenomenon, making its control a key aspect in improving engine design [3].…”