Recovery of Lube Base Oil from Used Lubricant Oil by Mixed Solvent Extraction

Abstract

Solvent extraction technique is one of the most efficiently extraction processes and the cheapest technique for recovering base oil from used lubricating oil. This research was to study recovery of base oil from used lubricant oil by mixed solvent extraction method. The three solvents were studied: 2-propanol, 1-butanol, and methyl-ethyl-ketone. The result showed that the mixture ratio by weight of solvents at 40:30:30 give the best performance of reducing the highest amount of heavy metals: Iron was reduced to 38.96 mg/kg, calcium 1565.63mg/kg and none aluminium. The color of the treated oil was also improved color by using vacuum distillation process at temperature of 320 to 420 ºC with 40 mbar pressure. The distillated base oil yield was 87.34 %wt and there was no iron and aluminium found only 6.778 mg/kg of calcium remains in it. The properties of base oil meet the requirements of lubricant oil by the department of energy standard.