Articles - Chemical Science & Engineering Research

Abstract

Quality assurance parameters of spent engine oil obtained from the same automobile engine after 2, 4 and 6 months usage corresponding to a distance coverage of 2200, 3800 and 5570 mileage were analyzed along with the parameters of a brand new Society of Automobile Engineers (SAE) 10W – 40 engine oil (the same type as the spent oil) using Anton Paar SVM 3000 densitometer, Karl Fischer titrator, Pensky-Martens closed cup flash point tester and Normalab pour point cabinet. Results obtained showed that the parameters of the spent engine oils were not within acceptable limits as specified by the SAE and deviations increased with increase in time duration as well as distance covered by engine oil, this is contrary to the parameters of the brand new engine oil which were within specification. Activated charcoal obtained from the bark of Anacardium Occidentale tree was employed to recycle the spent engine oils used after 2, 4 and 6 months respectively and results showed that kinematic viscosities, density, flash point and fire point of the spent engine oil after 6 months of usage increased from: 110.2300 mmsec^-1, 0.8611 gcm^-3, 112.8000 ⁰C and 216.0000 ⁰C to 133.7200 mmsec^-1, 0.8955 gcm^-3, 225.0000 ⁰C and 322.000 ⁰C respectively, also the water content and pour point reduced from 0.8000 % and -8.0000 ⁰C to 0.0800 % and -15.0000 ⁰C respectively.  Activated charcoal from the bark of Anacardium Occidentale tree is an anti-wear additive owing to its ability to increase the lubricity of the engine oil by increasing its kinematic viscosity and density, its ability to adsorb contaminants and volatile hydrocarbons in engine oil gives it the capacity to increase the flash and fire points of the engine oil.  The ability of this activated charcoal to reduce the water content and pour point of the spent engine oil confirms its hydrophilicity and ability to maintain the flow properties of oil at elevated temperatures.