Umudike Journal of Engineering and Technology

Reclamation of used engine oil using kaolin as the contacting agent was carried out. The used engine oil was acidified and bleached to remove the aromatic content and improve the colour and quality of the oil. Results showed that the viscosity index of the reclaimed oils from the samples labelled as A, B, C, D and E with oil to acid ratios of 3:1, 5:1, 10:1, 15:1 and 20:1 respectively are 94.95, 94.73, 94.38, 92.91 and 91.6 respectively, their flash point values – 162^oC, 175^oC, 180^oC, 200^oC and 193^oC respectively, their cloud point values are -9^oC, -9.5^oC, -9.8^oC, -10^oC, and -10^oC respectively and the specific gravity values are 0.932, 0.91, 0.88, 0.86 and 0.83 respectively. In addition, the reclaimed oil from sample A was found to have the highest Total Acid Number (TAN) while that from sample E had the least. Furthermore, only the reclaimed oils from samples C and D conformed with American Standards (ASTM) of reclaimed engine oil for flash points, viscosity index, colouration and TAN. It can be deduced that the combination of sulphuric acid and kaolin effectively reclaimed used engine oil and improve the reclaimed oil colour. Therefore formulations C and D are favourable for both automobile and industrial applications.