Characterization and Suitability of Reclaimed Automotive Lubricating Oils Reprocessed by Solvent Extraction Technology

Abstract

: The increase in the generation of used automotive lubricating oils is an issue of growing concern, especially in developing countries. Most used oil contains degraded additives and its indiscriminate disposal causes environmental degradation and pollution. This study investigates the characteristics of the reclaimed oil obtained by solvent extraction technology. It further evaluates the suitability of the reclaimed oil for reuse, by comparing its properties with the Society of Automotive Engineers (SAE) quality standards for lube oils. Three samples of used engine oils were collected, recycled and analyzed. Results from this study and other similar studies indicated that the flashpoint is below the SAE specifications. Viscosity index and kinematic viscosity at 40 and 100 °C are found above the SAE specifications. The pour point of the reclaimed oil is found below the standard values while the specific gravity concurs with the SAE standards. Total acid and total base numbers of the reclaimed oil indicated a low acid concentration. The study suggests an improvement on the flash point and the viscosity of the reclaimed oils for better lubricating performance in the automotive engines.