Enhancement of Biolubricant Production from Waste Cooking Oil using Alkali Derived from Oil-Palm empty Fruit Bunches

Abstract

This study focuses on the enhancement of biolubricant production by converting waste-cooking oil methyl esters (WOMEs) through the transesterification process. The potassium hydroxide (KOH) necessary for the transesterification was extracted from Oil-Palm Empty Fruit Bunches (OPEFB) through a multistep procedure involving cutting, sun-drying, burning, and soaking in distilled water. The resulting filtrate contained KOH at a concentration of 0.2 mol/dm³. To optimize the transesterification process, Response Surface Methodology (RSM) employing central composite design (CCD) was utilized. Three critical factors—temperature, mole ratio, and reaction time—were investigated for their influence on biolubricant yield. The study revealed that an optimal biolubricant yield of 98.5% could be achieved under the following pecific conditions: a temperature of 100°C, a mole ratio of 7:1, and a reaction time of 120 minutes. The predicted yield from the optimization correlates closely with the experimental results, indicating the efficacy of the optimization approach. Analysis of variance (ANOVA) underscored the significance of mole ratio and temperature as pivotal factors affecting biolubricant yield. This systematic investigation contributes valuable insights into the transesterification process, offering a sustainable approach to biolubricant production by utilizing waste cooking oil and KOH extracted from OPEFB. The findings provide a foundation for future research in the field of environmentally friendly lubricant synthesis.