Physicochemical Analysis and Characterization of Gasoline Engine oils

Abstract

Physicochemical changes in parameters such as viscosity at 40, 100oC, flash point, Total Base Number (TBN), water content, sulfated ash, wear elements, insoluble residue, gasoline fuel dilution and additive elements were assessed. Results indicate a decrease in TBN, additive elements, viscosity at 100oC, viscosity at 40oC, and flash point in the order of 4.9 %, 20%, 16.31, 25.9% and 26.9 for Fuchs oil, 12.6%, 1.62%, 17.76%, 21.35% and 44% for Tappco oil, 22% , 20%, 11.4%, 20.06% and 32.2% for Total oil, 49.4%, 12.1%, 14.8%, 19.46 and 20% for Petromin oil and 62.5%, 3.36%, 16.48%, 13.9% and 20.8% for Petronas oil respectively. A slight increase showed in wear and contaminant elements, sulfated ash and density. Wear, contaminant and additive elements were determined in fresh and used engine oils using Inductive Coupled Plasma Atomic Emission Spectroscopy (ICP). The result indicates no water content in used engine oils. Base oil samples were analyzed and the results of imported base oil indicate the presence of saturates 71.75 %, aromatic materials 25.88%, sulfur content 0.0741 % and viscosity index 107. The result base oil produced from Nile blend have saturates 82.2%, aromatics 16.78%, sulfur content 0.1704 % and viscosity index 99. The FTIR examination shows that base oil samples have identical spectra, and also shows oxidation in used oils. Gasoline fuel dilution and additives depletion were substantiated using GC and GC.MS techniques