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.

The thermal behavior of bituminous coal, coconut shell, and their blends during pyrolysis process was investigated in this study. The experiments were conducted at different weight percent of coconut shell (10, 20, 30, 40, and 50 wt%) and temperatures ranging from 30°C to 900°C. The DTG data for fuel blends showed additive profiles that reflected behavior of the individual fuel. When coconut shell was mixed with coal under weight percent of 20–50%, the nature of peaks in DTG profiles changed from higher to lower in the third stage reaction, shifting devolatilization temperature from 400°C to 450°C. This led to a decrease in the maximum rate of mass loss from 10.6% to 7.4%/min. However, the 10 wt% blend caused a slight increase in the maximum rate of mass loss from 10.6% to 11%/min. In addition, co-pyrolysis kinetics of fuel blends indicated that the blending of coconut shell with coal at BBR higher than 30% can increase the value of activation energy and induce slow pyrolysis of blends.